RARE EARTH REMOVAL OF HYDRATED AND HYDROXYL SPECIES
FIELD OF INVENTION
The present disclosure is related generally to rare earth removal of hydrated
and hydroxyl
species, more particularly to rare earth removal of metal and metalloid-
containing hydrated
and/or hydroxyl species.
BACKGROUND OF THE INVENTION
As fresh water resources grow increasingly scarce, water quality is rapidly
becoming a
major global concern. In addition to high levels of pollution from industrial
and municipal
sources and saltwater intrusion into fresh water acquifers, commonly used
disinfectants in
drinking water, particularly free chlorine (in the form of HOCl/OC1") and
monochloramine
(NH2C1), react with metals and metalloids to produce soluble products.
Monochloramine, for
.. example, is believed to react with lead to produce soluble Pb(II) products,
leading to elevated Pb
levels in drinking water.
Various technologies have been used to remove contaminants from municipal,
industrial,
and recreational waters. Examples of such techniques include adsorption on
high surface area
materials, such as alumina and activated carbon, ion exchange with anion
exchange resins, co-
precipitation and electrodialysis. However, most technologies for contaminant
removal are
hindered by the difficulty of removing problematic contaminants, more
particularly the difficulty
of removing metal and metalloid contaminant species.
SUMMARY OF THE INVENTION
These and other needs are addressed by the various embodiments and
configurations of
this disclosure. The present disclosure is directed to the use of rare earth-
containing
compositions to remove various contaminants, including metal and metalloid
target materials.
In one embodiment, a composition has the formula:
0
/ \
(H20)x Ce MS (1)
\ /
0
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where 0 <X < 8 and MS is one of the following:
M(H20)6", M(H2O)50H('), m(oH)(n-1) m(420)4(OH)2(n-2), M(OH)2(11-2),
M(1120)3(011)3(n-3), M(OH)3(11-3), M(H20)2(OH)4 '-4), M(OH)4("-4),
M(H20)(OH)5(-5), M(OH)5(-5),
M(011)6(' 6), M(F120)50(6 2), M(F120)4(0)2(n-4), m(i20)3(0)3(n-6),
M(H20)2(0)4(1-8), M(F120)(0)5(6-
10), x,fivi(.920)500,3(n-2), mc030-2), 11 III t-IN \ Anir-v-i\( ) MILT
FIN (rri )3(n-6),
M(H2O)4(CO3)2(4), , Iv( kk.A.-,3)2 =11-4
M(CO3)3(n-6), M(F120)2(CO3)4(6-8), W03)4(18), M(1120)(CO3)5(6-10), M(CO3)5(n-
10), M(CO3)6(1-12),
M(H20)46, M(H20)30H(6-1), M(H20)2(04(6-2), M(1120)(04(B-3), M(H20)30(11-2),
M(H20)2(0)2(n-4), and M(H20)(0)3(-6). "M" is a metal or metalloid having an
atomic number
selected from the group consisting of 5, 13, 22-33, 40-52, 56, 72-84, and 88-
94. The symbol "n"
is a real number < 8 and represents a charge or oxidation state of "M".
In one application, the composition is in a liquid media or medium, and the
media or
medium comprises a pH and Eh sufficient to favor MS as the primary species of
M.
In one application, M is one or more of boron, vanadium, chromium, cadmium,
antimony, lead, and bismuth.
In one embodiment, a method contacts, in a medium, a rare earth-containing
additive
with a metal or metalloid target material to remove the target material. The
target material is in
the form of a hydroxide, carbonate, hydrate, or oxyhydroxyl as a primary
species.
In one embodiment, a method is provided that contacts, in a medium, a rare
earth-
containing additive with one or more of a metal or metalloid hydroxide,
carbonate, and hydrate
to remove the metal or metalloid hydroxide, carbonate, and/or hydrate.
The rare earth-containing additive can be water soluble or water insoluble.
In one application, the target material has an atomic number selected from the
group
consisting of 5, 13, 22-33, 40-52, 56, 72-84, and 88-94.
In one application, the contacting step comprises the sub-steps:
(a) introducing, to the medium, an oxidizing agent to oxidize a target
material-
containing species to a primary species in the form of one or more of a metal
or metalloid
hydroxide, carbonate, oxyhydroxyl, and hydrate, the target material-containing
species being
different from the metal or metalloid hydroxide, carbonate, oxyhydroxyl,
and/or hydrate; and
(b) thereafter contacting, in the medium, the rare earth-containing additive
with the metal
or metalloid hydroxide, carbonate, oxyhydroxyl, and/or hydrate to remove the
metal or metalloid
hydroxide, carbonate, oxyhydroxyl, and/or hydrate.
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In one application, the the contacting step comprises the sub-steps:
(a) introducing, to the medium, a reducing agent to reduce a target
material-
containing species comprising the metal or metalloid to a primary species in
the form of the
metal or metalloid hydroxide, carbonate, oxyhydroxyl, and/or hydrate, the
target material-
containing species being different from the metal or metalloid hydroxide,
carbonate,
oxyhydroxyl, and/or hydrate; and
(b) thereafter contacting, in the medium, the rare earth-containing additive
with the metal
or metalloid hydroxide, carbonate, oxyhydroxyl, and/or hydrate to remove the
metal or metalloid
hydroxide, carbonate, oxyhydroxyl, and/or hydrate.
In one application, the contacting step comprises the sub-steps:
(a) introducing, to the medium, a base and/or base equivalent to convert a
target
material-containing species comprising the metal or metalloid to a primary
species in the form of
the metal or metalloid hydroxide, carbonate, oxyhydroxl, and/or hydrate, the
target material-
containing species being different from the metal or metalloid hydroxide,
carbonate,
oxyhydroxyl, and/or hydrate; and
(b) thereafter contacting, in the medium, the rare earth-containing additive
with the metal
or metalloid hydroxide, carbonate, and/or hydrate to remove the metal or
metalloid hydroxide,
carbonate, oxyhydroxyl, and/or hydrate.
In one application, the contacting step comprises the sub-steps:
(a) introducing, to the medium, an acid and/or acid equivalent to convert a
target
material-containing species comprising the metal or metalloid to a primary
species in the form of
the metal or metalloid hydroxide, carbonate, oxyhydroxyl, and/or hydrate, the
target material-
containing species being different from the metal or metalloid hydroxide,
carbonate,
oxyhydroxyl, and/or hydrate; and
(b) thereafter contacting, in the medium, the rare earth-containing
additive with the
metal or metalloid hydroxide, carbonate, oxyhydroxyl, and/or hydrate to remove
the metal or
metalloid hydroxide, carbonate, oxyhydroxyl, and/or hydrate.
The disclosure can have a number of advantages. For example, the rare earth-
containing
composition can remove effectively a large number of target materials, whether
in the form of
dissolved or undissolved species. As an illustration, the composition can
remove lead and lead
species in various forms, including as a colloid, hydrate, carbonate,
hydroxide, and oxyhydroxyl.
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The pH and/or Eh can be adjusted to produce a selected primary target material
species, which is
removed more effectively by the rare earth composition compared to rare earth
removal of other
target material species. High levels of removal of selected target materials
can therefore be
realized.
These and other advantages will be apparent from the disclosure.
As used herein, the term "a" or "an" entity refers to one or more of that
entity. As such,
the terms "a" (or "an"), "one or more" and "at least one" can be used
interchangeably herein. It is
also to be noted that the terms "comprising", "including", and "having" can be
used
interchangeably.
"Absorption" refers to the penetration of one substance into the inner
structure of another
substance, as distinguished from adsorption.
"Adsorption" refers to the adherence of atoms, ions, molecules, polyatomic
ions, or other
substances to the surface of another substance, called the adsorbent.
Typically, the attractive
force for adsorption can be in the form of a bond and/or force, such
ascovalent bonds, metallic
bonds, coordination bonds, ionic bonds, hydrogen bonds, electrostatic forces
(e.g., van der Waals
and/or London's forces), and the like.
"At least one", "one or more", and "and/or" are open-ended expressions that
are both
conjunctive and disjunctive in operation. For example, each of the expressions
"at least one of
A, B and C", "at least one of A, B, or C", "one or more of A, B, and C", "one
or more of A, B, or
C" and "A, B, and/or C" means A alone, B alone, C alone, A and B together, A
and C together, B
and C together, or A, B and C together. The term "water" refers to any aqueous
stream. The
water may originate from any aqueous stream may be derived from any natural
and/or industrial
source. Non-limiting examples of such aqueous streams and/or waters are
drinking waters,
potable waters, recreational waters, waters derived from manufacturing
processes, wastewaters,
pool waters, spa waters, cooling waters, boiler waters, process waters,
municipal waters, sewage
waters, agricultural waters, ground waters, power plant waters, remediation
waters, co-mingled
water and combinations thereof.
The terms "agglomerate" and "aggregate" refer to a composition formed by
gathering
one or more materials into a mass.
A "binder" generally refers to one or more substances that bind together a
material being
agglomerated. Binders are typically solids, semi-solids, or liquids. Non-
limiting examples of
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binders are polymeric materials, tar, pitch, asphalt, wax, cement water,
solutions, dispersions,
powders, silicates, gels, oils, alcohols, clays, starch, silicates, acids,
molasses, lime,
lignosulphonate oils, hydrocarbons, glycerin, stearate, or combinations
thereof. The binder may
or may not chemically react with the material being agglomerated. Non-liming
examples of
chemical reactions include hydration/dehydration, metal ion reactions,
precipitation/gelation
reactions, and surface charge modification.
A "carbonate" generally refers to a chemical compound containing the carbonate
radical
or ion (C012). Most familiar carbonates are salts that are formed by reacting
an inorganic base
(e.g., a metal hydroxide with carbonic acid (H2CO3). Normal carbonates are
formed when
.. equivalent amounts of acid and base react; bicarbonates, also called acid
carbonates or hydrogen
carbonates, are formed when the acid is present in excess. Examples of
carbonates include
sodium carbonate, (Na2CO3), sodium bicarbonate (NaHCO3), and potassium
carbonate (K2CO3).
The term "clarification" or "clarify" refers to the removal of suspended and,
possibly,
colloidal solids by gravitational settling techniques.
The term "coagulation" refers to the destabilization of colloids by
neutralizing the forces
that keep colloidal materials suspended. Cationic coagulants provide positive
electrical charge to
reduce the negative charge (zeta potential) of the colloids. The colloids
thereby form larger
particles (known as flocs).
The term "composition" generally refers to one or more chemical units composed
of one
or more atoms, such as a molecule, polyatomic ion, chemical compound,
coordination complex,
coordination compound, and the like. As will be appreciated, a composition can
be held together
by various types of bonds and/or forces, such as covalent bonds, metallic
bonds, coordination
bonds, ionic bonds, hydrogen bonds, electrostatic forces (e.g., van der Waal's
forces and
London's forces), and the like.
"Chemical species" or "species" are atoms, elements, molecules, molecular
fragments,
ions, compounds, and other chemical structures.
"Chemical transformation" refers to process where at least some of a material
has had its
chemical composition transformed by a chemical reaction. A "chemical
transformation" differs
from "a physical transformation". A physical transformation refers to a
process where the
chemical composition has not been chemically transformed but a physical
property, such as size
or shape, has been transformed.
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The term "contained within the water" generally refers to materials suspended
and/or
dissolved within the water. Water is typically a solvent for dissolved
materials and water-soluble
material. Furthermore, water is typically not a solvent for insoluble
materials and water-
insoluble materials. Suspended materials are substantially insoluble in water
and dissolved
materials are substantially soluble in water. The suspended materials have a
particle size.
"De-toxify" or "de-toxification" includes rendering a target material, such as
chemical
and/or biological target material non-toxic or non-harmful to a living
organism, such as, for
example, human or other animal. The target material may be rendered non-toxic
by converting
the target material into a non-toxic or non-harmful form or species.
The term "digest" or "digestion" refers to the use of microorganisms,
particularly
bacteria, to digest target materials. This is commonly established by mixing
forcefully
contaminated water with bacteria and molecularly oxygen.
The term "disinfect" or "disinfecting" refers to the use of an antimicrobial
agent to kill or
inhibit the growth of microorganisms, such as bacteria, fungi, protozoans, and
viruses. Common
antimicrobial agents include, oxidants, reductants, alchohols, aldehydes,
halogens, phenolics,
quaternary ammonium compounds, silver, copper, ultraviolet light, and other
materials.
The term "flocculation" refers to a process using a flocculant, which is
typically a
polymer, to form a bridge between flocs and bind the particles into large
agglomerates or
clumps. Bridging occurs when segments of the polymer chain adsorb on different
particles and
help particles aggregate.
The term "fluid" refers to a liquid, gas or both.
A "halogen" is a nonmetal element from Group 17 IUPAC Style (formerly: VII,
VITA) of
the periodic table, comprising fluorine (F), chlorine (Cl), bromine (Br),
iodine (I), and astatine
(At). The artificially created element 117, provisionally referred to by the
systematic name
ununseptium, may also be a halogen.
A "halide compound" is a compound having as one part of the compound at least
one
halogen atom and the other part the compound is an element or radical that is
less electronegative
(or more electropositive) than the halogen. The halide compound is typically a
fluoride,
chloride, bromide, iodide, or astatide compound. Many salts are halides having
a halide anion. A
halide anion is a halogen atom bearing a negative charge. The halide anions
are fluoride (F),
chloride (Cl-), bromide (Br), iodide (I) and astatide (At).
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A "hydroxyl" generally refers to a chemical functional group containing an
oxygen atom
connected by a covalent bond to a hydrogen atom. When it appears in a chemical
speices, the
hydroxyl group imparts some of the reactive and interactive properties of of
water (ionizability,
hydrogen bonding, etc.). Chemical species containing one or more hydroxyl
groups are typically
referred to as "hydroxyl species". The neutral form of the hydroxyl group is a
hydroxyl radical.
The anion form of the hydroxyl group (OH-) is called "an hydroxide" or
"hydroxide anion".
The term "hydrated species" generally refers to any of a class of compounds or
other
species containing chemically combined with water, whether occurring as a
solid or a fluid
component and whether occurring as a compound or charged species. In the case
of some
hydrates, as washing soda, Na2CO3 .10H20, the water is loosely held and is
easily lost on
heating; in others, as sulfuric acid, S03 -H20, or H2SO4, it is strongly held
as water of
constitution.
The term "inorganic material" generally refers to a chemical compound or other
species
that is not an organic material.
The term "insoluble" refers to materials that are intended to be and/or remain
as solids in
water. Insoluble materials are able to be retained in a device, such as a
column, or be readily
recovered from a batch reaction using physical means, such as filtration.
Insoluble materials
should be capable of prolonged exposure to water, over weeks or months, with
little loss of mass.
Typically, a little loss of mass refers to less than about 5% mass loss of the
insoluble material
after a prolonged exposure to water.
An "ion" generally refers to an atom or group of atoms having a charge. The
charge on
the ion may be negative or positive.
"Organic carbons" or "organic material" generally refer to any compound of
carbon
except such binary compounds as carbon oxides, the carbides, carbon disulfide,
etc.; such ternary
compounds as the metallic cyanides, metallic carbonyls, phosgene, carbonyl
sulfide, etc.; and the
metallic carbonates, such as alkali and alkaline earth metal carbonates.
The term "oxidizing agent" generally refers to one or both of a chemical
substance and
physical process that transfers and/or assists in removal of one or more
electrons from a
substance. The substance having the one or more electrons being removed is
oxidized. In
regards to the physical process, the physical process may removal and/or may
assist in the
removal of one or more electrons from the substance being oxidized. For
example, the substance
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CA 2832908 2019-01-02
to be oxidized can be oxidized by electromagnetic energy when the interaction
of the
electromagnetic energy with the substance be oxidized is sufficient to
substantially remove one
or more electrons from the substance. On the other hand, the interaction of
the electromagnetic
energy with the substance being oxidized may not be sufficient to remove one
or more electrons,
but may be enough to excite electrons to higher energy state, were the
electron in the excited
state can be more easily removed by one or more of a chemical substance,
thermal energy, or
such.
The terms "oxyanion" and/or "oxoanion" generally refers to anionic chemical
compounds
having a negative charge with a generic formula of AxOr (where A represents a
chemical
element other than oxygen," 0" represents the element oxygen and x, y and z
represent real
numbers). In the embodiments having oxyanions as a chemical contaminant, "A"
represents
metal, metalloid, and/or non-metal elements. Examples for metal-based
oxyanions include
chromate, tungstate, molybdate, aluminates, zirconate, etc. Examples of
metalloid-based
oxyanions include arsenate, arsenite, antimonate, germanate, silicate, etc.
Examples of non-
metal-based oxyanions include phosphate, selemate, sulfate, etc. Preferably,
the oxyanion
includes oxyanions of elements having an atomic number of 7, 13 to17, 22 to
26, 31 to 35, 40 to
42, 44, 45, 49 to 53, 72 to 75, 77, 78, 82, 83 85, 88, and 92. These elements
include These
elements include nitrogen, aluminum, silicon, phosphorous, sulfur, chlorine,
titanium, vanadium,
chromium, manganese, barium, arsenic, selenium, bromine, gallium, germanium,
zirconium,
niobium, molybdenum, ruthenium, rhodium, indium, tin, iodine, antimony,
tellurium, hafnium,
tantalum, tungsten, rhenium, iridium, platinum, lead, bismuth astatine,
radium, and uranium.
The terms "oxyspecies" and/or "oxospecies" generally refer to cationic,
anionic, or
neutral chemical compounds with a generic formula of AO y (where A represents
a chemical
element other than oxygen, 0 represents the element oxygen and x and y
represent real
numbers). In the embodiments having oxyanions as a chemical contaminant, "A"
represents
metal, metalloid, and/or non-metal elements. An oxyanion or oxoanion are a
type of oxyspecies
or oxospecies.
The term "polish" refers to any process, such as filtration, to remove small
(usually
microscopic) particulate material or very small low concentrations of
dissolved target material
from water.
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The terms "pore volume" and "pore size", respectively, refer to pore volume
and pore
size determinations made by any suite measure method. Preferably, the pore
size and pore
volume are determined by any suitable Barret-Joyner-Halenda method for
determining pore size
and volume. Furthermore, it can be appreciated that as used herein pore size
and pore diameter
can used interchangeably.
"Precipitation" generally refers to the removal of a dissolved target material
in the form
of an insoluble target material-laden rare earth composition. The target
material-laden rare earth
composition can comprise a target-laden cerium (IV) composition, a target-
laden rare earth-
containing additive composition, a target-laden rare composition comprising a
rare earth other
than cerium (IV), or a combination thereof. Typically, the target material-
laden rare earth
composition comprises an insoluble target material-laden rare earth
composition. For example,
"precipitation" includes processes, such as adsorption and absorption of the
target material by
one or more of the cerium (IV) composition, the rare earth-containing
additive, or a rare earth
other than cerium (IV). The target-material laden composition can comprise a
+3 rare earth,
such as cerium (III), lanthanum (III) or other lanthanoid having a +3
oxidation state.
A "principal species" generally refers to the major species in which a cation
is present,
under a specified set of conditions. Although usually applied to cations, the
term "principal
species" may be negatively charged or uncharged.
A "radical" generally refers to an atom or group of atoms that are joined
together in some
particular spatial structure and commonly take part in chemical reactions as a
single unit. A
radical is more generally an atom, molecule, or ion (group of atoms is
probably ok) with one or
more unpaired electrons. A radical may have a net positive or negative charge
or be neutral.
"Rare earth" refers to one or more of yttrium, scandium, lanthanum, cerium,
praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium,
holmium
erbium, thulium, ytterbium, and lutetium. As will be appreciated, lanthanum,
cerium,
praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium,
holmium
erbium, thulium, ytterbium, and lutetium are known as lanthanoids.
The terms "rare earth", "rare earth-containing composition", "rare earth-
containing
additive" and "rare earth-containing particle" refer both to singular and
plural forms of the terms.
By way of example, the term "rare earth" refers to a single rare earth and/or
combination and/or
mixture of rare earths and the term "rare earth-containing composition" refers
to a single
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composition comprising a single rare earth and/or a mixture of differing rare
earth-containing
compositions containing one or more rare earths and/or a single composition
containing one or
more rare earths. The terms "rare earth-containing additive" and "rare earth-
containing particle"
are additives or particles including a single composition comprising a single
rare earth and/or a
mixture of differing rare earth-containing compositions containing one or more
rare earths and/or
a single composition containing one or more rare earths. The term "processed
rare earth
composition" refers not only to any composition containing a rare earth other
than non-
compositionally altered rare earth-containing minerals. In other words, as
used herein
"processed rare earth-containing composition" excludes comminuted naturally
occurring rare
earth-containing minerals. However, as used herein "processed rare earth-
containing
composition" includes a rare earth-containing mineral where one or both of the
chemical
composition and chemical structure of the rare earth-containing portion of the
mineral has been
compositionally altered. More specifically, a comminuted naturally occurring
bastnasite would
not be considered a processed rare earth-containing composition and/or
processed rare earth-
.. containing additive. However, a synthetically prepared bastnasite or a rare
earth-containing
composition prepared by a chemical transformation of naturally occurring
bastnasite would be
considered a processed rare earth-containing composition and/or processed rare
earth-containing
additive. The processed rare earth and/or rare-containing composition and/or
additive are, in one
application, not a naturally occurring mineral but synthetically manufactured.
Exemplary
naturally occurring rare earth-containing minerals include bastnasite (a
carbonate-fluoride
mineral) and monazite. Other naturally occurring rare earth-containing
minerals include
aeschynite, allanite, apatite, britholite, brockite, cerite, fluorcerite,
fluorite, gadolinite, parisite,
stillwellite, synchisite, titanite, xenotime, zircon, and zirconolite.
Exemplary uranium minerals
include uraninite (UO2), pitchblende (a mixed oxide, usually U308), brannerite
(a complex oxide
of uranium, rare-earths, iron and titanium), coffinite (uranium silicate),
carnotite, autunite,
davidite, gummite, torbernite and uranophane. In one formulation, the rare
earth-containing
composition is substantially free of one or more elements in Group 1, 2, 4-15,
or 17 of the
Periodic Table, a radioactive species, such as uranium, sulfur, selenium,
tellurium, and
polonium.
The term "reducing agent", "reductant" or "reducer" generally refers to an
element or
compound that donates one or more electrons to another species or agent this
is reduced. In the
CA 2832908 2019-01-02
reducing process, the reducing agent is oxidized and the other species, which
accepts the one or
more electrons, is reduced.
The terminology "removal", "remove" or "removing" includes the sorbtion,
precipitation,
conversion, detoxification, deactivation, and/or combination thereof of a
target material
contained in a water and/or water handling system.
The term "soluble" refers to a material that readily dissolves in a fluid,
such as water or
other solvent. For purposes of this disclosure, it is anticipated that the
dissolution of a soluble
material would necessarily occur on a time scale of minutes rather than days.
For the material to
be considered to be soluble, it is necessary that the material/composition has
a significant
solubility in the fluid such that upwards of about 5 g of the material will
dissolve in about one
liter of the fluid and be stable in the fluid.
=
The term "sorb" refers to adsorption, absorption or both adsorption and
absorption.
The term "suspension" refers to a heterogeneous mixture of a solid, typically
in the form
of particulates dispersed in a liquid. In a suspension, the solid particulates
are in the form of a
discontinuous phase dispersed in a continuous liquid phase. The term "colloid"
refers to a
suspension comprising solid particulates that typically do not settle-out from
the continuous
liquid phase due to gravitational forces. A "colloid" typically refers to a
system having finely
divided particles ranging from about 10 to 10,000 angstroms in size, dispersed
within a
continuous medium. As used hereinafter, the terms "suspension", "colloid" or
"slurry" will be
used interchangeably to refer to one or more materials dispersed and/or
suspended in a
continuous liquid phase.
The term "surface area" refers to surface area of a material and/or substance
determined
by any suitable surface area measurement method. Preferably, the surface area
is determined by
any suitable Brunauer-Emmett-Teller (BET) analysis technique for determining
the specific area
of a material and/or substance.
The term "water handling system" refers to any system containing, conveying,
manipulating, physically transforming, chemically processing, mechanically
processing,
purifying, generating and/or forming the aqueous composition, treating, mixing
and/or co-
mingling the aqueous composition with one or more other waters and any
combination thereof.
A "water handling system component" refers to one or more unit operations
and/or pieces
of equipment that process and/or treat water (such as a holding tank, reactor,
purifier, treatment
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vessel or unit, mixing vessel or element, wash circuit, precipitation vessel,
separation vessel or
unit, settling tank or vessel, reservoir, pump, aerator, cooling tower, heat
exchanger, valve,
boiler, filtration device, solid liquid and/or gas liquid separator, nozzle,
tender, and such),
conduits interconnecting the unit operations and/or equipment (such as piping,
hoses, channels,
aqua-ducts, ditches, and such) and the water conveyed by the conduits. The
water handling
system components and conduits are in fluid communication.
The terms "water" and "water handling system" will be used interchangeably.
That is,
the term "water" may used to refer to "a water handling system" and the term
"water handling
system" may be used to refer to the term "water".
The preceding is a simplified summary of the disclosure to provide an
understanding of
some aspects of the disclosure. This summary is neither an extensive nor
exhaustive overview of
the disclosure and its various embodiments. It is intended neither to identify
key or critical
elements of the disclosure nor to delineate the scope of the disclosure but to
present selected
concepts of the disclosure in a simplified form as an introduction to the more
detailed description
presented below. As will be appreciated, other embodiments of the disclosure
are possible
utilizing, alone or in combination, one or more of the features set forth
above or described in
detail below, metal or metalloid having an atomic number selecting from the
group consisting of
5, 13, 22-33, 40-52, 72-84, and 89-94
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of
the
specification, illustrate embodiments of the disclosure and together with the
general description
of the disclosure given above and the detailed description given below, serve
to explain the
principles of the disclosure.
Fig. 1 depicts a water handling system and method according to an embodiment;
Figs. 2A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of boron;
Figs. 3A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of aluminum;
12
CA 2832908 2019-01-02
Figs. 4A-D depict prior art Pourbaix diagrams under specified conditions for
primary
species of thallium;
Figs. 5A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of vanadium;
Figs. 6A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of chromium;
Figs. 7A-F depict prior art Pourbaix diagrams under specified conditions for
primary
species of manganese;
Figs. 8A-F depict prior art Pourbaix diagrams under specified conditions for
primary
species of iron;
Figs. 9A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of cobalt;
Figs. 10A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of nickel;
Figs. 11A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of copper;
Figs. 12A-D depict prior art Pourbaix diagrams under specified conditions for
primary
species of zinc;
Figs. 13A-B depict prior art Pourbaix diagrams under specified conditions for
primary
species of gallium;
Fig. 14 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of germanium;
Figs. 15A-ll depict prior art Pourbaix diagrams under specified conditions for
primary
species of arsenic;
Figs. 16A-D depict prior art Pourbaix diagrams under specified conditions for
primary
species of zirconium;
Figs. 17A-D depict prior art Pourbaix diagrams under specified conditions for
primary
species of niobium;
Figs. 18A-C depict prior art Pourbaix diagrams under specified conditions for
primary
species of molybdenum;
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Figs. 19A-F depict prior art Pourbaix diagrams under specified conditions for
primary
species of technetium;
Figs. 20A-D depict prior art Pourbaix diagrams under specified conditions for
primary
species of ruthenium;
Figs. 21A-B depicts a prior art Pourbaix diagram under specified conditions
for primary
species of rhodium;
Figs. 22A-C depict prior art Pourbaix diagrams under specified conditions for
primary
species of palladium;
Figs. 23A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of silver;
Figs. 24A-C depict prior art Pourbaix diagrams under specified conditions for
primary
species of cadmium;
Figs. 25A-B depict prior art Pourbaix diagrams under specified conditions for
primary
species of indium;
Figs. 26A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of tin;
Figs. 27A-D depict prior art Pourbaix diagrams under specified conditions for
primary
species of antimony;
Fig. 28 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of tellurium;
Fig. 29 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of hafnium;
Fig. 30 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of lead;
Figs. 31A-B depict prior art Pourbaix diagrams under specified conditions for
primary
species of tungsten;
Figs. 32A-B depict prior art Pourbaix diagrams under specified conditions for
primary
species of rhenium;
Fig. 33 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of osmium;
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Fig. 34 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of uranium;
Figs. 35A-B depict prior art Pourbaix diagrams under specified conditions for
primary
species of platinum;
Figs. 36A-C depict prior art Pourbaix diagrams under specified conditions for
primary
species of gold;
Figs. 37A-D depict prior art Pourbaix diagrams under specified conditions for
primary
species of mercury;
Figs. 38A-E depict prior art Pourbaix diagrams under specified conditions for
primary
.. species of lead;
Fig. 39 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of lead;
Figs. 40A-C depict prior art Pourbaix diagrams under specified conditions for
primary
species of bismuth;
Figs. 41A-B depict prior art Pourbaix diagrams under specified conditions for
primary
species of polonium;
Figs. 42A-B depict prior art Pourbaix diagrams under specified conditions for
primary
species of actinium;
Figs. 43A-E depict prior art Pourbaix diagrams under specified conditions for
primary
.. species of thorium;
Figs. 44A-B depict prior art Pourbaix diagrams under specified conditions for
primary
species of protactinium;
Figs. 45A-G depict prior art Pourbaix diagrams under specified conditions for
primary
species of uranium;
Figs. 46A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of neptunium;
Figs. 47A-F depict prior art Pourbaix diagrams under specified conditions for
primary
species of plutonium;
Fig. 48 is a plot of loading capacity (mg/g) (vertical axis) versus arsenic
concentration
.. (g/L) (horizontal axis);
CA 2832908 2019-01-02
Fig. 49 is a plot of final arsenic concentration (mg/L) (vertical axis) versus
molar ratio of
cerium :arsenic (horizontal axis);
Fig. 50 is a plot of final arsenic concentration (mg/L) (vertical axis) versus
molar ratio of
cerium to arsenic (horizontal axis);
Fig. 51 is a series of XRD patterns for precipitates formed upon addition of
Ce (III) or Ce
(IV) solutions to sulfide-arsenite solutions and sulfate-arsenate solutions;
Fig. 52 is a plot of arsenic sequestered (micromol es) (vertical axis) and
cerium added
(micromoles) (horizontal axis);
Fig. 53 is a series of XRD patterns exhibiting the structural differences
between gasparite
(CeAs04) and the novel trigonal phase CeAs04 = (H20)x;
Fig. 54 is a series of XRD patterns exhibiting the structural differences
among trigonal
CeAs04 = (1120)x (experimental), trigonal CeAs04 = (H20)x (simulated), and
trigonal BiPO4 =
(H20)0.67 (simulated);
Fig. 55 is a plot of arsenic capacity (mg As/g Ce02) against various solution
compositions;
Fig. 56 is a plot of arsenic (V) concentration (ppb) against bed volumes
treated;
Fig. 57 is a plot of mg As/g Ce02 (vertical axis) against test solution
conditions
(horizontal axis);
Fig. 58 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of bismuth;
Fig. 59 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of aluminum;
Fig. 60 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of cobalt;
Fig. 61 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of chromium;
Fig. 62 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of manganese;
Fig. 63 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of copper;
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CA 2832908 2019-01-02
Fig. 64 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of zirconium;
Fig. 65 depicts a prior art Pourbaix diagram under specified conditions for
primary
species of zinc;
Figs. 66 A-E depict prior art Pourbaix diagrams under spccified conditions for
primary
species of barium; and
Figs. 67 A-E depict prior art Pourbaix diagrams under specified conditions for
primary
species of radium.
DETAILED DESCRIPTION
General Overview
As illustrated by Figure 1, the present disclosure is directed to removal from
and/or
detoxification of water, a water-handling system, or an aqueous medium or
other aqueous media,
of a target material or target material-containing species, such as a
pollutant or contaminant, by a
rare earth-containing composition, additive, or particle. Preferably, the rare
earth-containing
composition, additive, or particle is a processed rare earth-containing
composition, additive or
particle. In some embodiments, the target material or target material-
containing species is
removed and/or detoxified by forming a target material-laden rare earth-
containing composition
comprising the target material, target material-containing species, or a
derivative thereof. The
target material is one or more of an inorganic oxyspecics (other than an
oxyanion), a hydroxyl
species, which may comprise a hydroxide ion or hydroxyl radical, a hydrated
species, or a
combination thereof. The rare earth-containing composition may be soluble or
insoluble and
commonly is cerium, a cerium-containing compound, lanthanum, a lanthanum-
containing
compound, or a mixture thereof. A more common rare earth-containing
composition is cerium
(IV) oxide, cerium (III) oxide, a cerium (IV) salt, a cerium (III) salt,
lanthanum (III) oxide, a
lanthanum (III) salt, or a mixture thereof. The target material-laden rare
earth composition
comprises one or more of the target material and/or species thereof or a
portion of the target
material and/or species thereof.
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Rare Earth-Containing Additive
The rare earth-containing composition, additive, and/or particles may be water-
soluble,
water-insoluble, a combination of water-soluble and/or water-insoluble rare
earth-containing
compositions, additives, and/or particles, a partially water-soluble rare
earth-containing
composition, additive, and/or particles, and/or a partially water-insoluble
rare earth-containing
composition, additive and/or particles.
Commonly, the rare earth-containing composition, additive, and/or particles
comprise
cerium, in the form of a cerium-containng compound and/or dissociated ionic
form of cerium,
lanthanum, in the form of a lanthanum-containing compound and/or dissociated
ionic form of
lanthanum, or a mixture thereof. More common rare earth-containing
composition, additives,
and particles are cerium (IV) oxides, cerium (III) oxides, cerium (IV) salts,
cerium (III) salts,
lanthanum (III) oxides, lanthanum (III) salts, or mixtures and/or combinations
thereof.
The rare earth-containing composition, additive, and/or particles may contain
one or
more rare earths, and be in any suitable form, such as a free-flowing powder,
a liquid
formulation, or other form. Examples of rare earth-containing compositions,
additives, and
particles include cerium (III) oxides, cerium (IV) oxides, eerie (IV) salts
(such as ceric chloride,
eerie bromide, eerie iodide, eerie sulfate, eerie nitrate, eerie chlorate, and
eerie oxalate), cerium
(III) salts (such as cerous chloride, cerous bromide, cerous iodide, cerous
sulfate, cerous nitrate,
cerous chlorate, cerous chloride, and cerous oxalate), lanthanum (III) oxides,
a lanthanum (III)
salts (such as lanthanum chloride, lanthanum bromide, lanthanum iodide,
lanthanum chlorate,
lanthanum sulfate, lanthanum oxalate, and lanthanum nitrate), and mixtures
thereof.
The rare earth and/or rare earth-containing composition in the rare earth-
containing
additive can be rare earths in elemental, ionic or compounded forms. The rare
earth and/or rare
earth-containing composition can be contained in a fluid, such as water, or in
the form of
nanoparticles, particles larger than nanoparticles, agglomerates, or
aggregates or combinations
and/or mixtures thereof. The rare earth and/or rare earth-containing
composition can be
supported or unsupported. The rare earth and/or rare earth-containing
composition can comprise
one or more rare earths. The rare earths may be of the same or different
valence and/or oxidation
states and/or numbers. The rare earths can be a mixture of different rare
earths, such as two or
more of yttrium, scandium, cerium, lanthanum, praseodymium, and neodymium.
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CA 2832908 2019-01-02
The rare earth and/or rare earth-containing composition is, in one
application, a processed
rare earth-containing composition and does not include, or is substantially
free of, a naturally
occurring and/or derived mineral. In one formulation, the rare earth and/or
rare earth-containing
composition is substantially free of one or more elements in Group 1, 2, 4-15,
or 17 of the
Periodic Table, and is substantially free of a radioactive species, such as
uranium, sulfur,
selenium, tellurium, and polonium.
In some formulations, the rare earth-containing composition comprises one or
more rare
earths. While not wanting to be limited by example, the rare earth-containing
composition can
comprise a first rare earth and a second rare earth. The first and second rare
earths may have the
same or differing atomic numbers. In some formulations, the first rare earth
comprises cerium
(III) and the second rare earth comprises a rare earth other than cerium
(III). The rare earth other
than cerium (III) can be one or more trivalent rare earths, cerium (IV), or
any other rare other
than trivalent cerium. For example, a mixture of rare earth-containing
compositions can
comprise a first rare earth having a +3 oxidation state and a second rare
earth having a +4
oxidation state. In some embodiments, the first and second rare earths are the
same and comprise
cerium. More specifically, the first rare earth comprises cerium (III) and the
second rare earth
comprises cerium (IV). Preferably, the cerium is primarily in the form of a
water-soluble cerium
(III) salt, with the remaining cerium being present as cerium oxide, a
substantially water
insoluble cerium composition.
In one formulation, the cerium is primarily in the form of cerium (IV) oxide
while the
remaining cerium is present as a dissociated cerium (III) salt. For rare earth-
containing
compositions having a mixture of +3 and +4 oxidations states commonly at least
some of the rare
earth has a +4 oxidation sate, more commonly at least most of the rare earth
has a +4 oxidation
state, more commonly at least about 75 wt% of the rare earth has a +4
oxidation state, even more
commonly at least about 90 wt% of the rare earth has a +4 oxidation state, and
yet even more
commonly at least about 98 wt% of the rare earth has a +4 oxidation state. The
rare earth-
containing composition commonly includes at least about 1 ppm, more commonly
at least about
10 ppm, and even more commonly at least about 100 ppm of a cerium (III) salt.
While in some
embodiments, the rare earth-containing composition includes at least about
0.0001 wt% cerium
(III) salt, preferably at least about 0.001 wt% cerium (III) salt and even
more preferably at least
about 0.01 wt% cerium (III) salt calculated as cerium oxide. Moreover, in some
embodiments,
19
CA 2832908 2019-01-02
the rare earth composition-containing commonly has at least about 20,000 ppm
cerium (IV),
more commonly at least about 100,000 ppm cerium (IV) and even more commonly at
least about
250,000 ppm cerium (IV).
In some formulations, the molar ratio of cerium (IV) to cerium (III) is about
1 to about
1X10-6, more commonly is about 1 to about 1X10-5, even more commonly is about
1 to about
1X104, yet even more commonly is about 1 to about 1X10-3, still yet even more
commonly is
about 1 to about 1X10-2, still yet even more commonly is about 1 to about 1X10-
1, or still yet
even more commonly is about 1 to about 1. Moreover, in some formulations the
molar ratio of
cerium (III) to cerium (IV) is aboutl to about 1X10-6, more commonly is about
1 to about 1X10-
1 0 5, even more commonly is about 1 to about 1X10-4, yet even more
commonly is about 1 to about
1X10-3, still yet even more commonly is about 1 to about 1X10-2, still yet
even more commonly
is about 1 to about 1X10-1, or still yet even more commonly is about 1 to
about 1. Further, these
molar ratios apply for any combinations of soluble and insoluble forms of
Ce(III) and soluble
and insoluble forms of Ce(IV).
In one formulation, the cerium is primarily in the form of a dissociated
cerium (III) salt,
with the remaining cerium being present as cerium (IV) oxide. For rare earth-
containing
compositions having a mixture of +3 and +4 oxidations states commonly at least
some of the rare
earth has a +3 oxidation sate, more commonly at least most of the rare earth
has a +3 oxidation
state, more commonly at least about 75 wt% of the rare earth has a +3
oxidation state, even more
commonly at least about 90 wt% of the rare earth has a +3 oxidation state, and
yet even more
commonly at least about 98 wt% of the rare earth has a +3 oxidation state. The
rare earth-
containing composition commonly includes at least about 1 ppm, more commonly
at least about
10 ppm, and even more commonly at least about 100 ppm cerium (IV) oxide. While
in some
embodiments, the rare earth-containing composition includes at least about
0.0001 wt% cerium
(IV), preferably at least about 0.001 wt% cerium (IV) and even more preferably
at least about
0.01 wt% cerium (IV) calculated as cerium oxide. Moreover, in some
embodiments, the rare
earth composition-containing commonly has at least about 20,000 ppm cerium
(III), more
commonly at least about 100,000 ppm cerium (III) and even more commonly at
least about
250,000 ppm cerium (III).
In some formulations, the molar ratio of cerium (III) to cerium (IV) is about
1 to about
1X10-6, more commonly is about 1 to about 1X10-5, even more commonly is about
1 to about
CA 2832908 2019-01-02
1X10-4, yet even more commonly is about 1 to about 1X10-3, still yet even more
commonly is
about 1 to about 1X10-2, still yet even more commonly is about 1 to about 1X10-
1, or still yet
even more commonly is about 1 to about 1. Moreover, in some formulations the
molar ratio of
cerium (IV) to cerium (III) is aboutl to about 1X10-6, more commonly is about
1 to about 1X10-
5, even more commonly is about 1 to about 1X10-4, yet even more commonly is
about 1 to about
1X10-3, still yet even more commonly is about 1 to about 1X10-2, still yet
even more commonly
is about 1 to about 1X10-1, or still yet even more commonly is about 1 to
about 1. Further, these
molar ratios apply for any combinations of soluble and insoluble forms of
Ce(III) and soluble
and insoluble forms of Ce(IV).
Having a mixture of +3 and +4 cerium, preferably in the form of a dissociated
cerium
(III) salt and a cerium (IV) composition, can be advantageous. Preferred, non-
limiting examples
of cerium (IV) compositions are: cerium (IV) dioxide, cerium (IV) oxide,
cerium (IV)
oxyhydroxide, cerium (IV) hydroxide, and hydrous cerium (IV) oxide. For
example, having
dissociated cerium (III) provides for the opportunity to take advantage of
cerium (III) solution
sorbtion and/or precipitation chemistries, such as, but not limited to, the
formation of insoluble
cerium oxyanion compositions. Furthermore, having a cerium (IV) composition
presents,
provides for the opportunity to take advantage of sorbtion and
oxidation/reduction chemistries of
cerium (IV), such as, the strong interaction of cerium (IV) with compositions
such as metal
and/or metalloid target material-containing species. Commonly, cerium (IV) is
also referred to
as cerium (+4) and/or eerie.
In one formulation, the rare earth composition comprises a water-soluble rare
earth
composition having a +3 oxidation state. Non-limiting examples of suitable
water-soluble rare
earth compositions include rare earth chlorides, rare earth bromides, rare
earth iodides, rare earth
astatides, rare earth nitrates, rare earth sulfates, rare earth oxalates, rare
earth perchlorates, rare
earth carbonates, and mixtures thereof. In one formulation, the rare earth-
containing additive
includes water-soluble cerium (III) and lanthanum (III) compositions. In some
applications, the
water-soluble cerium composition comprises cerium (III) chloride, CeC13.
Commonly, cerium
(III) is also referred to as cerium (+3) and/or cerous.
More preferably, the rare earth composition comprises a water-soluble cerium
+3
composition. Non-limiting examples of suitable water-soluble cerium +3
compositions are
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CA 2832908 2019-01-02
cerium (III) chloride, cerium (III) nitrate, cerium (III) sulfate, cerium
(III) oxalate, and a mixture
thereof.
In some formulations, the water-soluble cerium (III) composition may comprise,
in
addition to cerium, one or more other water soluble rare earths. The rare
earths other than cerium
.. include yttrium, scandium, lanthanum, praseodymium, neodymium, samarium,
europium,
gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and
lutetium. The other
rare earths may and may not be water-soluble.
In some formulations, the water-soluble cerium-containing additive contains
water-
soluble cerium (III) and one or more other water-soluble trivalent rare earths
(such as, but not
limited to, one or more of lanthanum, neodymium, praseodymium and samarium).
The molar
ratio of cerium (III) to the other trivalent rare earths is commonly at least
about 1:1, more
commonly at least about 10:1, more commonly at least about 15:1, more commonly
at least
about 20:1, more commonly at least about 25:1, more commonly at least about
30:1, more
commonly at least about 35:1, more commonly at least about 40:1, more commonly
at least
about 45:1, and more commonly at least about 50:1.
In some formulations, the water-soluble cerium-containing additive contains
cerium (III)
and one or more of water-soluble lanthanum, neodymium, praseodymium and
samarium. The
water-soluble rare earth-containing additive commonly includes at least about
0.01 wt.% of one
or more of lanthanum, neodymium, praseodymium and samarium. The water-soluble
rare earth-
containing additive commonly has on a dry basis no more than about 10 wt.% La,
more
commonly no more than about 9 wt.% La, even more commonly no more than about 8
wt.% La,
even more commonly no more than about 7 wt.% La, even more commonly no more
than about
6 wt.% La, even more commonly no more than about 5 wt.% La, even more commonly
no more
than about 4 wt.% La, even more commonly no more than about 3 wt.% La, even
more
commonly no more than about 2 wt.% La, even more commonly no more than about 1
wt.% La,
even more commonly no more than about 0.5 wt.% La, and even more commonly no
more than
about 0.1 wt.% La. The water-soluble rare earth-containing additive commonly
has on a dry
basis no more than about 8 wt.% Nd, more commonly no more than about 7 wt.%
Nd, even more
commonly no more than about 6 wt.% Nd, even more commonly no more than about 5
wt.% Nd,
even more commonly no more than about 4 wt.% Nd, even more commonly no more
than about
3 wt.% Nd, even more commonly no more than about 2 wt.% Nd, even more commonly
no more
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CA 2832908 2019-01-02
than about 1 wt.% Nd, even more commonly no more than about 0.5 wt.% Nd, and
even more
commonly no more than about 0.1 wt.% Nd. The water-soluble rare earth-
containing additive
commonly has on a dry basis no more than about 5 wt.% Pr, more commonly no
more than about
4 wt.% Pr, even more commonly no more than about 3 wt.% Pr, even more commonly
no more
than about 2.5 wt.% Pr, even more commonly no more than about 2.0 wt.% Pr,
even more
commonly no more than about 1.5 wt.% Pr, even more commonly no more than about
1.0 wt.%
Pr, even more commonly no more than about 0.5 wt.% Pr, even more commonly no
more than
about 0.4 wt.% Pr, even more commonly no more than about 0.3 wt.% Pr, even
more commonly
no more than about 0.2 wt.% Pr, and even more commonly no more than about 0.1
wt.% Pr. The
water-soluble rare earth-containing additive commonly has on a dry basis no
more than about 3
wt.% Sm, more commonly no more than about 2.5 wt.% Sm, even more commonly no
more than
about 2.0 wt.% Sm, even more commonly no more than about 1.5 wt.% Sm, even
more
commonly no more than about 1.0 wt.% Sm, even more commonly no more than about
0.5 wt.%
Sm, even more commonly no more than about 0.4 wt.% Sm, even more commonly no
more than
about 0.3 wt.% Sm, even more commonly no more than about 0.2 wt.% Sm, even
more
commonly no more than about 0.1 wt.% Sm, even more commonly no more than about
0.05
wt.% Sm, and even more commonly no more than about 0.01 wt.% Sm.
In some formulations, the water-soluble cerium-containing additive contains
water-
soluble cerium (III) and one or more other water-soluble trivalent rare earths
(such as one or
more of lanthanum, neodymium, praseodymium and samarium). The molar ratio of
cerium (III)
to the other trivalent rare earths is commonly at least about 1:1, more
commonly at least about
10:1, more commonly at least about 15:1, more commonly at least about 20:1,
more commonly
at least about 25:1, more commonly at least about 30:1, more commonly at least
about 35:1,
more commonly at least about 40:1, more commonly at least about 45:1, and more
commonly at
least about 50:1.
In one formulation, the rare earth-containing additive consists essentially of
a water-
soluble cerium (III) salt, such as a cerium (Ill) chloride, cerium (III)
bromide, cerium (III)
iodide, cerium (III) astatide, cerium perhalogenates, cerium (III) carbonate,
cerium (III) nitrate,
cerium (III) sulfate, cerium (III) oxalate and mixtures thereof. The rare
earth in this formulation
commonly is primarily cerium (III), more commonly at least about 75 mole% of
the rare earth
content of the rare earth-containing additive is cerium (III), that is no more
than about 25 mole%
23
CA 2832908 2019-01-02
of the rare earth content of the rare earth-containing additive comprises rare
earths other than
cerium (III). Even more commonly, the rare earth in this formulation commonly
is primarily at
least about 80 mole% cerium (III), yet even more commonly at least about 85
mole% cerium
(III), still yet even more commonly at least about 90 mole% cerium (III), and
yet still even more
commonly at least about 95 mole% cerium (III).
The rare earth composition may comprise a water insoluble composition, such as
a water-
insoluble rare earth oxide, oxyhydroxide, and/or hydrous oxide. The insoluble
rare earth
composition may be in the form of a dispersion, suspension or slurry of rare
earth particulates.
The rare earth particulates can have an average particle size ranging from the
sub-micron, to
.. micron or greater than micron. The insoluble rare earth composition may
have a surface area of
at least about 1 m2/g. Commonly, the insoluble rare earth has a surface area
of at least about 70
m2/g. In another formulation, the insoluble rare earth composition may have a
surface area from
about 25 m2/g to about 500 m2/g.
In some formulations, the rare earth composition may be agglomerated.
Commonly, the
rare earth composition may be in the form of agglomerate, the agglomerate
comprising a
polymeric binder and rare earth-containing composition.
In one formulation, the rare earth-containing additive comprises a rare earth
and/or rare
earth-containing composition comprising at least some water insoluble cerium
(IV) and water-
soluble cerium (III) and/or lanthanum (III). The rare earth and/or rare earth-
containing
composition comprise at least some water-soluble cerium (III), typically in
the form of water-
soluble cerium (III) salt. Commonly, the rare earth-containing additive
comprises more than
about 1 wt.% of a water-soluble cerium (III) composition, more commonly more
than about 5
wt.% of a water-soluble cerium (III) composition, even more commonly more than
about 10
wt.% of a water-soluble cerium (III) composition, yet even more commonly more
than about 20
wt.% of a water-soluble cerium (III) composition, still yet even more commonly
more than about
wt.% of a water-soluble cerium (III) composition, or still yet even more
commonly more than
about 40 wt.% of a water-soluble cerium (III) composition.
In accordance with some formulations, the rare earth-containing additive
typically
comprises more than about 50 wt.% of a water-soluble cerium (III) composition,
more typically
30 the rare earth-containing additive comprises more than about 60 wt.% of
a water-soluble cerium
(III) composition, even more typically the rare earth-containing additive
comprises more than
24
CA 2832908 2019-01-02
about 65 wt.% of a water-soluble cerium (III) composition, yet even more
typically the rare
earth-containing additive comprises more than about 70 wt.% of a water-soluble
cerium (III)
composition, still yet even more typically the rare earth-containing additive
comprises more than
about 75 wt.% of a water-soluble cerium (III) composition, still yet even more
typically the rare
earth-containing additive comprises more than about 80 wt.% of a water-soluble
cerium (III)
composition, still yet even more typically the rare earth-containing additive
comprises more than
about 85 wt.% of a water-soluble cerium (III) composition, still yet even more
typically the rare
earth-containing additive comprises more than about 90 wt.% of a water-soluble
cerium (III)
composition, still yet even more typically the rare earth-containing additive
comprises more than
about 95 wt.% of a water-soluble cerium (III) composition, still yet even more
typically the rare
earth-containing additive comprises more than about 98 wt.% of a water-soluble
cerium (III)
composition, still yet even more typically the rare earth-containing additive
comprises more than
about 99 wt.% of a water-soluble cerium (III) composition, or yet still eve
more typically
comprises about 100 wt.% of a water-soluble cerium (III) composition.
In some formulations, the rare earth-containing additive comprises one or more
nitrogen-
containing materials. The one or more nitrogen-containing materials, commonly,
comprise one
or more of ammonia, an ammonium-containing composition, a primary amine, a
secondary
amine, a tertiary amine, an amide, a cyclic amine, a cyclic amide, a
polycyclic amine, a
polycyclic amide, and combinations thereof. The nitrogen-containing materials
are typically less
than about 1 ppm, less than about 5 ppm, less than about 10 ppm, less than
about 25 ppm, less
than about 50 ppm, less about 100 ppm, less than about 200 ppm, less than
about 500 ppm, less
than about 750 ppm or less than about 1000 ppm of the water-soluble rare earth-
containing
additive. Commonly, the rare earth-containing additive comprises a water-
soluble cerium (III)
and/or lanthanum (III) composition. More commonly, the rare earth-containing
additive
comprises cerium (III) chloride. The rare earth-containing additive is
typically dissolved in a
liquid. The liquid is the rare earth-containing additive is dissolved in is
preferably water.
In some formulations, the rare earth-containing additive is in the form of one
or more of:
an aqueous solution containing substantially dissociated, dissolved forms of
the rare earths
and/or rare earth-containing compositions; free flowing granules, powder,
particles, and/or
.. particulates of rare earths and/or rare earth-containing compositions
containing at least some
water-soluble cerium (III); free flowing aggregated granules, powder,
particles, and/or
CA 2832908 2019-01-02
particulates of rare earths and/or rare earth-containing compositions
substantially free of a binder
and containing at least some water-soluble cerium (III); free flowing
agglomerated granules,
powder, particles, and/or particulates comprising a binder and rare earths
and/or rare earth-
containing compositions one or both of in an aggregated and non-aggregated
form and
containing at least some water-soluble cerium (III); rare earths and/or rare
earth-containing
compositions containing at least some water-soluble cerium (III) and supported
on substrate; and
combinations thereof.
Regarding particulate forms of rare earth-containing compositions, the
particles, in one
formulation, have a particle size may be from about 1 nanometer to about 1000
nanometers. In
another embodiment the particles may have a particle size less than about 1
nanometer. In yet
another embodiment the particles may have a particle size from about 1
micrometer to about
1,000 micrometers.
Regarding rare earths and/or rare earth-containing compositions supported on a
substrate,
suitable substrates can include porous and fluid permeable solids having a
desired shape and
physical dimensions. The substrate, for example, can be a sintered ceramic,
sintered metal,
micro-porous carbon, glass fiber, cellulosic fiber, alumina, gamma-alumina,
activated alumina,
acidified alumina, a metal oxide containing labile anions, crystalline alumino-
silicate such as a
zeolite, amorphous silica-alumina, ion exchange resin, clay, ferric sulfate,
porous ceramic, and
the like. Such substrates can be in the form of mesh, such as screens, tubes,
honeycomb
structures, monoliths, and blocks of various shapes, including cylinders and
toroids. The
structure of the substrate will vary depending on the application. Suitable
structural forms of the
substrate can include a woven substrate, non-woven substrate, porous membrane,
filter, fabric,
textile, or other fluid permeable structure. The rare earth-containing
additive can be incorporated
into or coated onto a filter block or monolith for use as a filter, such as a
cross-flow type filter.
The rare earth and/or rare earth-containing additive can be in the form of
particles coated on to or
incorporated in the substrate. In some configurations, the rare earth and/or
rare earth-containing
additive can be ionically substituted for cations in the substrate. Typically,
the rare earth-coated
substrate comprises_at least about 0.1% by weight, more typically 1% by
weight, more typically
at least about 5% by weight, more typically at least about 10% by weight, more
typically at least
about 15% by weight, more typically at least about 20% by weight, more
typically at least about
25% by weight, more typically at least about 30% by weight, more typically at
least about 35%
26
CA 2832908 2019-01-02
by weight, more typically at least about 40% by weight, more typically at
least about 45% by
weight, and more typically at least about 50% by weight rare earth and/or rare
earth-containing
composition. Typically, the rare earth-coated substrate includes no more than
about 95% by
weight, more typically no more than about 90% by weight, more typically no
more than about
85% by weight, more typically no more than about 80% by weight, more typically
no more than
about 75% by weight, more typically no more than about 70% by weight, and even
more
typically no more than about 65% by weight rare earth and/or rare earth-
containing composition.
In some formulations, the rare earth-containing additive includes a rare earth-
containing
composition supported on, coated on, or incorporated into a substrate,
preferably the rare earth-
containing composition is in the form of particulates. The rare earth-
containing particulates can,
for example, be supported or coated on the substrate with or without a binder.
The binder may
be any suitable binder, such as those set forth herein.
Further regarding formulations comprising the rare earth-containing additive
comprising
rare earth-containing granules, powder, particles, and/or particulates
agglomerated and/or
aggregated together with or without a binder, such formulations commonly have
a mean, median,
or 1390 particle size of at least about 1 gm, more commonly at least about 5
gm, more commonly
at least about 10 gm, still more commonly at least about 25 gm. In some
formulations, the rare
earth-containing agglomerates or aggregates have a mean, median, or 1390
particle size
distribution from about 100 to about 5,000 microns; a mean, median, or P90
particle size
distribution from about 200 to about 2,500 microns; a mean, median, or 1390
particle size
distribution from about 250 to about 2,500 microns; or a mean, median, or P90
particle size
distribution from about 300 to about 500 microns. In other formulations, the
agglomerates
and/or aggregates can have a mean, median, or 1390 particle size distribution
of at least about 100
nm, specifically at least about 250 nm, more specifically at least about 500
nm, even more
specifically at least about 1 gm and yet even more specifically at least about
0.5 nm, the mean,
median, or P90 particle size distribution of the agglomerates and/or
aggregates can be up to about
1 micron or more. Moreover, the rare earth-containing particulates,
individually and/or in the
form of agglomerates and/or aggregates, can have in some cases a surface area
of at least about 5
m2/g, in other cases at least about 10 m2/g, in other cases at least about 70
m2/g, in yet other
cases at least about 85 m2/g, in still yet other cases at least about 100
m2/g, in still yet other cases
at least about 115 m2/g, in still yet other cases at least about 125 m2/g, in
still yet other cases at
27
CA 2832908 2019-01-02
least about 150 m2/g, in still yet other cases at least 300 m2/g, and in still
yet other cases at least
about 400 m2/g. In some configurations, the rare earth-containing
particulates, individually
and/or in the form of agglomerates or aggregates commonly can have a surface
area from about
50 to about 500 m2/g, or more commonly from about 110 to about 250 m2/g.
Commonly, the
rare earth-containing agglomerate includes more than 10.01wt.%, more commonly
more than
about 85 wt.%, even more commonly more than about 90 wt.%, yet even more
commonly more
than about 92 wt.% and still yet even more commonly from about 95 to about
96.5 wt.% rare
earth-containing particulates, with the balance being primarily the binder.
Stated another way,
the binder can be less than about 15% by weight of the agglomerate, in some
cases less than
about 10% by weight, in still other cases less than about 8% by weight, in
still other cases less
than about 5% by weight, and in still other cases less than about 3.5% by
weight of the
agglomerate. In some formulations, the rare earth-containing particulates are
in the form of
powder and have aggregated nano-crystalline domains. The binder can include
one or more
polymers selected from the group consisting of thermosetting polymers,
thermoplastic polymers,
elastomeric polymers, cellulosic polymers and glasses. Preferably, the binder
comprises a
fluorocarbon-containing polymer and/or an acrylic-polymer.
In one embodiment, the rare earth-containing composition is in the form of a
colloid,
suspension, or slurry of particulates. The particulates commonly can have a
mean, median
and/or Py0 particle size of less than about 1 nanometer, more commonly a mean,
median and/or
P90 particle size from about 1 nanometer to about 1,000 nanometers, even more
commonly a
mean, median and/or P90 particle size from about 1 micron to about 1,000
microns, or yet even
more commonly a mean, median and/or PY0 particle size of at least about 1,000
microns.
Preferably, the particulates have a mean, median and/or Pyo particle size from
about 0.1 to about
1,000 nm, more preferably from about 0.1 to about 500 nm. Even more
preferably, the cerium
(IV) particulates have a mean, median and/or Pyo particle size from about 0.2
to about 100 nm.
In some embodiments, the particulates may have a mean and/or median surface
area of at
least about 1 m2/g, preferably a mean and/or median surface area of at least
about 70 m2/g. In
other embodiments, the particulates may preferably have a mean and/or median
surface area
from about 25 m2/g to about 500 m2/g and more preferably, a mean and/or median
surface area
of about 100 to about 250 m2/g. In some embodiments, the particulates may be
in the form of
one or more of a granule, crystal, crystallite, and particle.
28
CA 2832908 2019-01-02
In one application, the particulates comprise cerium (IV), typically as cerium
(IV) oxide.
The weight percent (wt.%) cerium (IV) content based on the total rare earth
content of the
cerium (IV) particulates typically is at least about 50 wt.% cerium (IV), more
typically at least
about 60 wt.% cerium (IV), even more typically at least about 70 wt.% cerium
(IV), yet even
more typically at least about 75 wt.% cerium (IV), still yet even more
typically at least about 80
wt.% cerium (IV), still yet even more typically at least about 85 wt.% cerium
(IV), still yet even
more typically at least about 90 wt.% cerium (IV), still yet even more
typically at least about 95
wt.% cerium (IV), and even more typically at least about 99 wt.% cerium (IV).
Preferably, the
cerium (IV) particulate is substantially devoid of rare earths other than
cerium (IV). More
preferably, the weight percent (wt.%) cerium (IV) content based on the total
rare earth content of
the cerium (IV) particulates is about100 wt.% cerium (IV) and comprises one or
more of cerium
(IV) oxide, cerium (IV) hydroxide, cerium (IV) oxyhydroxyl, cerium (IV)
hydrous oxide, cerium
(IV) hydrous oxyhydroxyl, Ce02, and/or Ce(IV)(0),(OH)(OH)y-zH20, where w, x, y
and can
be zero or a positive, real number.
The Medium (or Media) 104
The medium (or media) 104 can be any fluid stream. The fluid stream may be
derived
from any source containing one or more target materials. Commonly, the medium
(or media)
104 is derived from any aqueous source containing one or more target
materials. Non-limiting
examples of a suitable medium (or media) 104 is recreational waters, municipal
waters (such as,
sewage, waste, agricultural, or ground waters), industrial (such as cooling,
boiler, or process
waters), wastewaters, well waters, septic waters, drinking waters, naturally
occurring waters,
(such as a lake, pond, reservoir, river, or stream), and/or other waters
and/or aqueous process
streams.
Non-limiting examples of recreational waters are swimming pool waters, brine
pool
waters, therapy pool waters, diving pool waters, sauna waters, spa waters, and
hot tub waters.
Non-limiting examples of municipal waters are drinking waters, waters for
irrigation, well
waters, waters for agricultural use, waters for architectural use, reflective
pool waters, water-
fountain waters, water-wall waters, use, non-potable waters for municipal use
and other non-
potable municipal waters. Wastewaters include without limitation, municipal
and/or agricultural
run-off waters, septic waters, waters formed and/or generated during an
industrial and/or
manufacturing process, waters formed and/or generated by a medical facility,
waters associated
29
CA 2832908 2019-01-02
with mining, mineral production, recovery and/or processing (including
petroleum), evaporation
pound waters, and non-potable disposal waters. Well waters include without
limitation waters
produced from a subsurface well for the purpose of human consumption,
agricultural use
(including consumption by a animal, irrigation of crops or consumption by
domesticated farm
animals), mineral-containing waters, waters associated with mining and
petroleum production.
Non-limiting examples of naturally occurring waters include associated with
rains, storms,
streams, rivers, lakes, aquifers, estuaries, lagoons, and such.
The medium (or media) 104 is typically obtained from one or more of the above
sources
and processed, conveyed and/or manipulated by a water handling system. The
medium (or
media) can be primarily the water in a water handling system.
The water handling system components and configuration can vary depending on
the
treatment process, water, and water source. While not wanting to limited by
example, municipal
and/or wastewater handling systems typically one or more of the following
process units:
clarifying, disinfecting, coagulating, aerating, filtering, separating solids
and liquids, digesting,
and polishing. The number and ordering of the process units can vary.
Furthermore, some
process units may occur two or more times within a water handling system. It
can be appreciated
that the one or more process units are in fluid communication.
The water handling system may or may not have a clarifier. Some water handling
systems may have more than one clarifier, such as primary and final
clarifiers. Clarifiers
typically reduce cloudiness of the water by removing biological matter (such
as bacteria and/or
algae), suspended and/or dispersed chemicals and/or particulates from the
water. Commonly a
clarification process occurs before and/or after a filtration process.
The water handling system may or may not contain a filtering process.
Typically, the
water handling system contains at least one filtering process. Non-limiting
examples of common
filtering processes include without limitation screen filtration, trickling
filtration, particulate
filtration, sand filtration, macro-filtration, micro-filtration, ultra-
filtration, nano-filtration, reverse
osmosis, carbon/activated carbon filtration, dual media filtration, gravity
filtration and
combinations thereof. Commonly a filtration process occurs before and/or after
a disinfection
process. For example, a filtration process to remove solid debris, such as
solid organic matter
and grit from the water typically precedes the disinfection process. In some
embodiments, a
filtration process, such as an activated carbon and/or sand filtrations
follows the disinfection
CA 2832908 2019-01-02
process. The post-disinfection filtration process removes at least some of the
chemical
disinfectant remaining in the treated water.
The water handling system may or may not include a disinfection process. The
disinfection process may include without limitation treating the aqueous
stream and/or water
with one or more of fluorine, fluorination, chlorine, chlorination, bromine,
bromination, iodine,
iodination, ozone, ozonation, electromagnetic irradiation, ultra-violet light,
gama rays,
electrolysis, chlorine dioxide, hypochlorite, heat, ultrasound,
trichloroisocyanuric acid,
soaps/detergents, alcohols, bromine chloride (BrC1), cupric ion (Cu2+),
silver, silver ion (AO,
permanganate, phenols, and combinations thereof. Preferably, the water
handling system
contains a single disinfection process, more preferably the water handling
system contains two or
more disinfection processes. Disinfection process are typically provided to
one of at least
remove, kill and/or detoxify pathogenic material contained in the water.
Typically, the
pathogenic material comprises biological contaminants, in particular
biological contaminants
comprising the target materials. In some embodiments, the disinfection process
converts the
target material species into a species that can be removed and/or detoxified
by the rare earth-
containing composition, additive, and/or particle or particulate.
The water handling system may or may not include coagulation. The water
handling
system may contain one or more coagulation processes. Typically, the
coagulation process
includes adding a flocculent to the water in the water handling system.
Typical flocculants
include aluminum sulfate, polyelectrolytes, polymers, lime and ferric
chloride. The flocculent
aggregates the particulate matter suspended and/or dispersed in the water, the
aggregated
particulate matter forms a coagulum. The coagulation process may or may not
include
separating the coagulum from the liquid phase. In some embodiments,
coagulation may
comprise part, or all, the entire clarification process. In other embodiments,
the coagulation
process is separate and distinct from the clarification process. Typically,
the coagulation process
occurs before the disinfection process.
The water handling system may or may not include aeration. Within the water
handing
system, aeration comprises passing a stream of air and/or molecular oxygen
through the water
contained in the water handling system. The aeration process promotes
oxidation of
contaminants contained in the water being processed by the water handling
system, preferably
the aeration promotes the oxidation of biological contaminates, such as target
materials. In some
31
CA 2832908 2019-01-02
embodiments, the aeration process converts the target material species into a
species that can be
removed and/or detoxified by the rare earth-containing composition, additive,
and/or particle or
particulate. The water handling system may contain one or more aeration
processes. Typically,
the disinfection process occurs after the aeration process.
The water handling system may or may not have one or more of a heater, a
cooler, and a
heat exchanger to heat and/or cool the water being processed by the water
handling system. The
heater may be any method suitable for heating the water. Non-limiting examples
of suitable
heating processes are solar heating systems, electromagnetic heating systems
(such as, induction
heating, microwave heating and infrared), immersion heaters, and thermal
transfer heating
systems (such as, combustion, stream, hot oil, and such, where the thermal
heating source has a
higher temperature than the water and transfers heat to the water to increase
the temperature of
the water). The heat exchanger can be any process that transfers thermal
energy to or from the
water. The heat exchanger can remove thermal energy from the water to cool
and/or decrease
the temperature of the water. Or, the heat exchanger can transfer thermal
energy to the water to
.. heat and/or increase the temperature of the water. The cooler may be any
method suitable for
cooling the water. Non-limiting examples of suitable cooling process are
refrigeration process,
evaporative coolers, and thermal transfer cooling systems (such as, chillers
and such where the
thermal (cooling) source has a lower temperature than the water and removes
heat from the water
to decrease the temperature of the water). Any of the clarification,
disinfection, coagulation,
.. aeration, filtration, sludge treatment, digestion, nutrient control,
solid/liquid separation, and/or
polisher processes may further include before, after and/or during one or both
of a heating and
cooling process. It can be appreciated that a heat exchanger typically
includes at least one of
heating and cooling process.
The water handling system may or may not include a digestion process.
Typically, the
digestion process is one of an anaerobic or aerobic digestion process. In some
configurations,
the digestion process may include one of an anaerobic or aerobic digestion
process followed by
the other of the anaerobic or aerobic digestion processes. For example, one
such configuration
can be an aerobic digestion process followed by an anaerobic digestion
process. Commonly, the
digestion process comprises microorganisms that breakdown the biodegradable
material
.. contained in the water. In some embodiments, the biodegradable material
includes a target
material. Furthermore, the digestion process converts the target material
species into a species
32
CA 2832908 2019-01-02
that can be removed and/or detoxified by the rare earth-containing
composition, additive, and/or
particle or particulate. The anaerobic digestion of biodegradable material
proceeds in the
absence of oxygen, while the aerobic digestion of biodegradable material
proceeds in the
presence of oxygen. In some water handling systems the digestion process is
typically referred
to as biological stage/digester or biological treatment stage/digester.
Moreover, in some systems
the disinfection process comprises a digestion process.
The water handling system may or may not include a nutrient control process.
Furthermore, the water handling system may include one or more nutrient
control processes.
The nutrient control process typically includes nitrogen and/or phosphorous
control. Moreover,
nitrogen control commonly may include nitrifying bacteria. Typically,
phosphorous control
refers to biological phosphorous control, preferably controlling phosphorous
that can be used as
a nutrient for algae. Nutrient control typically includes processes associated
with control of
oxygen demand substances, which include in addition to nutrients, pathogens,
and inorganic and
synthetic organic compositions. The nutrient control process can occur before
or after the
disinfection process. In some embodiments, the nutrient control process
converts the target
material species into a species that can be removed and/or detoxified by the
rare earth-containing
composition, additive, and/or particle or particulate.
The water handling system may or may not include a solid/liquid separation
process.
Preferably, the water handling system includes one or more solid/liquid
separation processes.
The solid/liquid separation process can comprise any process for separating a
solid phase from a
liquid phase, such as water. Non-limiting examples of suitable solid liquid
separation processes
are clarification (including trickling filtration), filtration (as described
above), vacuum and/or
pressure filtration, cyclone (including hydrocyclones), floatation,
sedimentation (including
gravity sedimentation), coagulation (as described above), sedimentation
(including, but not
limited to grit chambers), and combinations thereof.
The water handling system may or may not include a polisher. The polishing
process can
include one or more of removing fine particulates from the water, an ion-
exchange process to
soften the water, an adjustment to the pH value of the water, or a combination
thereof.
Typically, the polishing process is after the disinfection step.
While the water handling system typically includes one or more of a
clarifying,
disinfecting, coagulating, aerating, filtering, separating solids and liquids,
digesting, and
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CA 2832908 2019-01-02
polishing processes, the water handling system may further include additional
processing
equipment. The additional processing equipment includes without limitation
holding tanks,
reactors, purifiers, treatment vessels or units, mixing vessels or elements,
wash circuits,
precipitation vessels, separation vessels or units, settling tanks or vessels,
reservoirs, pumps,
cooling towers, heat exchangers, valves, boilers, gas liquid separators,
nozzles, tenders, and such.
Furthermore, the water handling system includes conduit(s) interconnecting the
unit operations
and/or additional processing equipment. The conduits include without
limitation piping, hoses,
channels, aqua-ducts, ditches, and such. The water is conveyed to and from the
unit operations
and/or additional processing equipment by the conduit(s). Moreover, each unit
operations and/or
additional processing equipment is in fluid communication with the other unit
operations and/or
additional processing equipment by the conduits.
The Target Material
The aqueous medium that is treated by the rare earth-containing composition,
additive,
and/or particles may contain one or more target materials. The one or more
target material-
containing species may include metals (other than scandium, yttrium and
lanthanoids),
metalloids, and/or radioactive isotopes in various forms. In some aqueous
media, the target
material-containing species include, without limitation, a hydrated metal
(including without
limitation alkali metals, alkaline earth metals, actinoids, transition metals,
and post-transition
metals and excluding scandium, yttrium and lanthanoids), metalloid, and/or
radioactive isotope,
a hydrated metal, metalloid, or radioactive isotope oxyspecies in the form of
an anion, cation, or
having no net charge (e.g., Ma0,, or MaOx where 0 <a < 4, 0 <x < 4, and 0 < n
< 6), a
positively, negatively, or uncharged metal, metalloid, or radioactive isotope
carbonate (e.g.,
M(CO3) y where 0 <c < 4 and 0 <y < 4), or a positively, negatively, or
uncharged metal,
metalloid, or radioactive isotope hydroxyl species (particularly a metal or
metalloid hydroxide
(e.g., M(OH), where 0 <z < 8)), a positively, negatively, uncharged metal,
metalloid, or
radioactive isotope oxyhydroxyl species and mixtures thereof. The target
material-containing
species may be in the form of a solid, a dissolved species, or a suspension.
In some embodiments, the rare earth-containing composition removes anionic,
cationic,
oxy, hydroxyl, hydrated, or a combination thereof species of a target
material, where the target
material "M" has an atomic number of 5, 13, 22-33, 40-52, 72-84, and 89-94.
Examples of
34
CA 2832908 2019-01-02
hydrated hydroxyl and hydrated oxy compounds (which may be anionic, neutral or
cationic and
hereinafter referenced by the symbol "MS") include, but are not limited to,
M(H20)6",
M(H20)50H(-1), M(OH)(-1) M(H20)4(OH)2(-2), iviitn(oH)2(n-2),
ivilk4(1920)3(OH)3(11-3), m(0,9)3(-3),
M(H20)2(OH)4(1-4), M(OH)4 -4), M(H20)(OH)50-5), M(OH)55, M(OH)6('6, M(H20)50(n-
2),
moo-2), M(H20)4(0)2(n-4), m02(-4), M(H20)3(0)3(n-6), mo3(n-6), M(H20)2(0)4(n-
8), M04("),
M(H20)(0)5(n-10), mo5(n-10), m(o)6(n-'2), m(i2o)5co3(n-2), mc0301-2), AM'
)4k,.r,n3 fi t ( )
..,-1n 4 ,
M(CO3)2(n-4), Aff(Er cr+c-, (--1-1 ) IkAnj 1-11 ( ) ( )
j3kk_AJ3 )3-()n 6 , ( n 6 , 8 n , n ,
M(H20)(CO3)5(n-10), M(CO3)5(11-1()), M(CO3)6('1-12), /LT (-1\ ffir_T (-
1\ ) Atitu r-11 /nu\ (
ivikri2v)4n, nakii2k.1)2k%-,11)2
n
M(F120)(OH)3(n-3), M(1120)30(n-2), M(F120)2(0)2(n-4), M(H20)(0)3(n-6), and
M(0)4(-8). In the
foregoing formulas, n is a real number no greater than eight and represents
the charge or
oxidation state of the metal or metalloid "M" (for example when M is Pb(II) n
is 2, and when M
is Pb(IV) n is 4). In general, M has a positive charge "n" no greater than
about 8.
Pourbaix diagrams are depicted in Figures 2-47 for each of the metals,
metalloids, and
radioactive isotopes. Figures 2-47 depict the primary species of target
material under different
thermodynamic conditions of an aqueous solution. With reference to Figure 39,
the target
material lead has the following species: Pb(H20)621-, Pb(H20)4(0)2,
Pb(H20)5CO3,
Pb(H20)4(CO3)22-, Pb(H20)3(OH)3-, Pb(H20)4(OH)2, Pb(H20)2(OH)42-, and
Pb(H20)(0)32-. The
state of the lead compounds (whether solid(s) or aqueousoo) are shown in the
lead Pourbaix
diagrams. Typically, the lead comprises lead having a +2 oxidation state. With
reference to
Figure 27, the target material antimony has the following species:
Sb(H20)2(OH)41-,
Sb(H20)4(OH)21-', Sb(H20)3(OH)3, Sb(H20)(OH)5, and Sb(OH)61-. Typically, the
antimony
comprises antimony having one of a +5 or +3 oxidation state. With reference to
Figure 40, the
target material bismuth has the following species: Bi(H20)63+, Bi(H20)5(OH)2+,
Bi(H20)4(OH)21+, Bi(H20)3(OH)3, and Bi(H20)2(OH)41-. Typically, the bismuth
comprises
.. bismuth having one of a +5 or +3 oxidation state.
There are a number of possible mechanisms for removing target materials. The
precise
mechanism may depend on a number of variables including the particular form
and/or
characteristics of the rare earth-containing composition, additive, and/or
particle or particulate,
the particular form and/or characteristics of the target material, the pH of
the medium 104, the Eh
of the medium 104, the temperature of the medium 104, the components in the
medium 104, and
other parameters known to those of skill in the art.
CA 2832908 2019-01-02
While not wishing to be bound by any theory, the anionic form of the target
material may
be one or more of sorbed, precipitated, complexed, ionically bound, inter-
valance shell
complexed (with any one or more hybridized or non-hybridized s, p, d or f
orbitals), covalently
bounded or a combination thereof with the rare earth-containing composition.
The anionic forms
may comprise an oxyanion, hydroxyl, hydrated or combination thereof of the
target material
having a net negative charge. While not wishing to be bound by any theory, the
target material
may selectively interact with a face or an edge of rare earth-containing
composition particulate.
Another theory, which we do not wish to be bound by, is that the anionic
target material forms a
substantially insoluble product with a rare earth. The rare earth may be in
the form of a
substantially water soluble rare earth-containing salt or in the form of a
substantially water
insoluble material that strongly sorbs, binds, chemically reacts or such with
the anionic target
material.
While not wishing to be bound by any theory, there are a number of mechanisms
for
removing cationic forms of the target materials. The cationic forms may
comprise complexed,
hydroxyl, hydrated or combination thereof of the target material having a net
positive charge.
While not wishing to be bound by any theory, the cationic form of the target
material may be one
or more of sorbed, precipitated, complexed, ionically bound, inter-valance
shell complexed (with
any one or more hybridized or non-hybridized s, p, d or f orbitals),
covalently bounded or a
combination thereof with the rare earth-containing composition. While not
wishing to be bound
by any theory, the target material may selectively interact with a face or an
edge of rare earth-
containing composition particulate. Another theory, which we do not wish to be
bound by, is
that the cationic target material form a substantially insoluble and/or stable
product with rare
earth cation.
While not wishing to be bound by any theory, another possible mechanism for
the
removal of anionic, cationic, or uncharged species containing the target
material is that a species,
such as a water of hydration, hydroxyl radical, hydroxide ion, or carbonate
species, compounded,
complexed, or otherwise attached to the target material acts as a chemical
entity that attaches,
sorbs and/or chemically bonds to the rare earth or rare earth-containing
composition. While not
wanting to be limited by theory and/or by way of illustration, a possible
cationic metal or
metalloid adsorption process may comprise, as show in chemical equation (2):
0
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CA 2832908 2019-01-02
M(1-120)62+ + Ce02 = Ce M(H20)42+ + 2 H20 (2)
of
The rare earth may be in the form of a substantially water soluble rare earth-
containing
salt or in the form of a substantially water insoluble material that strongly
sorbs, binds,
chemically reacts or otherwise attaches to the cationic target material, as
shown in chemical
equation (3).
0
M(H20)62+ + Ce(OH)2(H20)4+ (H20)4Ce M(H20)4+ + 2 H30+ (3)
\ 0/
where M has an atomic number commonly of one of 5, 13, 22-33, 40-52, 72-84,
and 89-94 and
more commonly one of 5, 13, 22 to 33, 40 to 52, 56, 72, 80-84, 88, and 90-94.
Although the
number of waters of hydration is shown as "4" for ceria oxide, it is to be
understood that more or
less waters of hydration may be present depending on the application.
While not wanting to be limited by theory and by way of further example, a
possible
cationic lead adsorption process may comprise, as show in chemical equation
(4):
/0\
Pb(H20)62+ + Ce02 = de Pb(H20)42+ + 2 H20 (4)
0
The rare earth cations may be in the form of a substantially water soluble
rare earth-
containing salt or in the form of a substantially water insoluble material
that strongly sorbs,
binds, chemically reacts or such with the cationic target material, as shown
in chemical equation
(5)-
Pb(H20)62+ + Ce(OH)2(H20)4+ (H20)4Ce Pb(H20)4+ + 2 1-130+ (5)
0
While not wishing to be bound by any theory, another possible mechanism the
rare earth-
containing additive, such as cerium (IV) oxide, may oxidize the target
material and/or target
material-containing species. The contacting of the rare earth-containing
oxidizing agent and the
target material-containing species may one or both: a) chemically interact
with the target
37
CA 2832908 2019-01-02
material-containing species and b) form a reduced rare earth and/or rare earth-
containing
oxidizing agent and an oxidized target material and/or target material-
containing species. By
way of illustration, a cerium (IV) oxidizing agent may be formed by contacting
a first cerium-
containing composition having cerium in a +3 oxidation state with an oxidant
(as listed below) to
form a second cerium-containing composition having cerium in a +4 oxidation
state (or cerium
(IV) oxidizing agent). Commonly, the second cerium-containing composition
comprises Ce02
particles. The cerium (IV) oxidizing agent then oxidizes the target material
or target material-
containing species forming the first (reduced) cerium (III)-containing
composition.
Regardless of the precise mechanism, contact of the rare earth-containing
additive with
the target material-containing species forms a rare earth- and target material-
containing product.
The rare earth- and target material-containing product can be in the form of a
material dissolved
in the water or a solid material either contained within the water or a solid
material phase
separated from the water. The solid rare earth- and target material-containing
product may be a
precipitate, a solid particle suspended within the water, a flocculated solid
particle, and
combination thereof.
As can be seen from the prior art Pourbaix diagrams in Figures 2-47, the
primary species
of a metal or metalloid in solution depends on pH and Eh. The values are
commonly selected
such that the water is electrochemically stable and the target material is a
dissolved (not solid)
species. Cationic forms of lead, for example, typically, but not necessarily,
are present, as the
.. primary species, in aqueous media having a pH of less than about pH 7 and
Eh of less than about
+1 V. As discussed below, the form of metal or metalloid present in solution,
and therefore the
efficacy of precipitating, sorbing, or otherwise removing the metal or
metalloid from, and/or de-
toxifying, the aqueous medium by treatment with the rare earth-containing
composition, additive,
and/or particle or particulate can be increased substantially by adjusting one
or both of the pH
and Eh of the medium. It can be appreciated that, while the efficacy of
precipitating, sorbing, or
removing the target material has been illustrated for various pH and Eh
values, the concept of
adjusting one or both of pH and Eh is applicable for effectively removing
and/or detoxifying an
aqueous solution for components, including interferents, other than the metal
and/or metalloid-
containing target materials.
In accordance with some embodiments, the target material is removed from the
aqueous
media having a selected pH value. Commonly, the selected pH value of the
aqueous media may
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CA 2832908 2019-01-02
be from about pH 0 to about pH 14, more commonly the pH of the aqueous media
may be from
about pH 1 to about pH 13, even more commonly the pH of the aqueous media may
be from
about pH 2 to about pH 12, even more commonly the pH of the aqueous media may
be from
about pH 3 to about pH 11, yet even more commonly the pH of the aqueous media
may be from
.. about pH 4 to about pH 10, still yet even more commonly the pH of the
aqueous media may be
from about pH 5 to about pH 9, or still yet even more commonly the pH of the
aqueous media
may be from about pH 6 to about pH 8.
In one embodiment, the aqueous media typically has a selected pH value of from
about
pH 6 to about pH 9, and more typically the aqueous media has a pH of from
about pH 6.5 to
about pH 8.5
Commonly in other embodiments, the aqueous media may be substantially acidic
having
a selected pH of about pH 0, more commonly having a selected pH of about pH 1,
even more
commonly having a selected pH of about pH 2, yet even more commonly having a
selected pH
of about pH 3, or still yet even more commonly having a selected pH about pH
4. Even more
commonly in other embodiments, the aqueous media may be substantially neutral
having a
selected pH of about pH 5, more commonly having a selected pH of about pH 6,
even more
commonly having a selected pH of about pH 7, yet even more commonly having a
selected pH
of about pH 8, or still yet even more commonly having a selected pH of about
pH 9. Commonly
in other embodiments, the aqueous media may be substantially basic having a
selected pH of
about pH 10, more commonly having a selected pH of about pH 11, even more
commonly
having a selected pH of about pH 12, yet even more commonly having a selected
pH of about pH
13, or still yet even more commonly having a selected pH about pH 14.
In accordance with some embodiments, the target material is removed from the
aqueous
media having a selected Eh value with respect to standardized reference
electrode, such as a
standard hydrogen electrode (SHE). Commonly, the selected Eh of the aqueous
medium is at
least about -0.5 V, more commonly at least about -0.4 V, more commonly at
least about -0.3 V,
more commonly at least about -0.2 V, more commonly at least about -0.1 V, more
commonly at
least about 0 V, more commonly at least about 0.1 V, more commonly at least
about 0.2 V, more
commonly at least about 0.3 V, and more commonly at least about 0.4 V, and
more commonly at
least about 0.5 V. Commonly, the selected Eh of the aqueous medium is below
the level at
which water is not electrochemically stable, more commonly no more than about
1.7 V, more
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CA 2832908 2019-01-02
commonly no more than about 1.6 V, more commonly no more than about 1.5 V,
more
commonly no more than about 1.4 V, more commonly no more than about 1.3 V,
more
commonly no more than about 1.2 V, more commonly no more than about 1.1 V,
more
commonly no more than about 1.0 V, more commonly no more than about 0.9 V,
more
commonly no more than about 0.8 V, and more commonly no more than about 0.7 V.
The rare earth to target material ratio of the insoluble rare earth- and
target material-
containing product can also vary depending on the solution pH and/or Eh value.
In other words,
rare earths having a rare earth to target material ratio less than 1 have a
greater molar removal
capacity of target material than rare earths having a rare earth to target
material ratio of 1 or
more than 1. In some embodiments, the greater the pH value the greater the
rare earth to target
material ratio. In other embodiments, the greater the pH value the smaller the
rare earth to target
material ratio. In yet other embodiment, the rare earth to target material
ratio is substantially
unchanged over a range of pH values. In some embodiments, the rare earth to
target material
ratio is no more than about 0.1, the rare earth to target material ratio is no
more than about 0.2,
the rare earth to target material ratio is no more about 0.3, the rare earth
to target material ratio is
no more than about 0.4, the rare earth to target material ratio is no more
than about 0.5, the rare
earth to target material ratio is no more than about 0.6, the rare earth to
target material ratio is no
more than about 0.7, the rare earth to target material ratio is no more than
about 0.8, the rare
earth to target material ratio is no more than about 0.9, the rare earth to
target material ratio is no
more than about 1.0, the rare earth to target material ratio is no more than
about 1.1, the rare
earth to target material ratio is no more than about 1.2, the rare earth to
target material ratio is no
more than about 1.3, the rare earth to target material ratio is no more than
about 1.4, the rare
earth to target material ratio is no more than about 1.5, the rare earth to
target material ratio is no
more than about 1.6, the rare earth to target material ratio is no more than
about 1.7, the rare
earth to target material ratio is no more about 1.8, the rare earth to target
material ratio is no
more than about 1.9, the rare earth to target material ratio is no more than
about 1.9, or the rare
earth to target material ratio is more than about 2.0 at a pH value of no more
than about pH -2, at
a pH value of more than about pH -1, at a pH value of more than about pH 0, at
a pH value of
more than about pH 1, at a pH value of more than about pH 2, at a pH value of
more than about
pH 3, at a pH value of more than about pH 4, at a pH value of more than about
pH 5, at a pH
value of more than about pH 6, at a pH value of more than about pH 7, at a pH
value of more
CA 2832908 2019-01-02
than about pH 8, at a pH value of more than about pH 9, at a pH value of more
than about pH 10,
at a pH value of more than about pH 11, at a pH value of more than about pH
12, at a pH value
of more than about pH 13, or at a pH value of more than about pH 14.
In some embodiments, the rare earth to target material ratio is no more than
about 0.1, the
rare earth to target material ratio is no more than about 0.2, the rare earth
to target material ratio
is no more about 0.3, the rare earth to target material ratio is no more than
about 0.4, the rare
earth to target material ratio is no more than about 0.5, the rare earth to
target material ratio is no
more than about 0.6, the rare earth to target material ratio is no more than
about 0.7, the rare
earth to target material ratio is no more than about 0.8, the rare earth to
target material ratio is no
more than about 0.9, the rare earth to target material ratio is no more than
about 1.0, the rare
earth to target material ratio is no more than about 1.1, the rare earth to
target material ratio is no
more than about 1.2, the rare earth to target material ratio is no more than
about 1.3, the rare
earth to target material ratio is no more than about 1.4, the rare earth to
target material ratio is no
more than about 1.5, the rare earth to target material ratio is no more than
about 1.6, the rare
earth to target material ratio is no more than about 1.7, the rare earth to
target material ratio is no
more about 1.8, the rare earth to target material ratio is no more than about
1.9, the rare earth to
target material ratio is no more than about 1.9, or the rare earth to target
material ratio is more
than about 2.0 at a water pH value of no more than about pH -2, at a water pH
value of more than
about pH -1, at a water pH value of more than about pH 0, at a water pH value
of more than
.. about pH 1, at a water pH value of more than about pH 2, at a water pH
value of more than about
pH 3, at a water pH value of more than about pH 4, at a water pH value of more
than about pH 5,
at a water pH value of more than about pH 6, at a water pH value of more than
about pH 7, at a
water pH value of more than about pH 8, at a water pH value of more than about
pH 9, at a water
pH value of more than about pH 10, at a water pH value of more than about pH
11, at a water pll
.. value of more than about pH 12, at a water pH value of more than about pH
13, or at a water pH
value of more than about pH 14.
For Ce02 as the rare earth-containing composition, additive, and/or particle
or particulate,
removal capacities of approximately 0.1 mg target material/g REO (e.g. Ce02)
or less can be
encountered. These can have rare earth:target material ratios that are
significantly larger than 2.
For example, 0.1 mg is 0.0001 g, so 1 g Ce02/0.0001 g target material =
10,000. In such
embodiments, the rare earth to target material ratio is commonly no more than
about 50,000, the
41
CA 2832908 2019-01-02
rare earth to target material ratio is more commonly no more than about
47,500, the rare earth to
target material ratio is more commonly no more about 45,000, the rare earth to
target material
ratio is more commonly no more than about 42,500, the rare earth to target
material ratio is more
commonly no more than about 40,000, the rare earth to target material ratio is
no more than
about 37,500, the rare earth to target material ratio is more commonly no more
than about
35,000, the rare earth to target material ratio is more commonly no more than
about 35,000, the
rare earth to target material ratio is more commonly no more than about
32,500, the rare earth to
target material ratio is more commonly no more than about 30,000, the rare
earth to target
material ratio is more commonly no more than about 37,500, the rare earth to
target material
ratio is more commonly no more than about 35,000, the rare earth to target
material ratio is more
commonly no more than about 32,500, the rare earth to target material ratio is
more commonly
no more than about 30,000, the rare earth to target material ratio is more
commonly no more than
about 27,500, the rare earth to target material ratio is more commonly no more
than about
25,000, the rare earth to target material ratio is more commonly no more than
about 22,500, or
the rare earth to target material ratio is more commonly no more about 20,000,
at a water pH
value of no more than about pH -2, at a water pH value of more than about pH -
1, at a water pH
value of more than about pH 0, at a water pH value of more than about pH 1, at
a water pH value
of more than about pH 2, at a water pH value of more than about pH 3, at a
water pH value of
more than about pH 4, at a water pH value of more than about pH 5, at a water
pH value of more
than about pH 6, at a water pH value of more than about pH 7, at a water pH
value of more than
about pH 8, at a water pH value of more than about pH 9, at a water pH value
of more than about
pH 10, at a water pH value of more than about pH 11, at a water pH value of
more than about pH
12, at a water pH value of more than about pH 13, or at a water pH value of
more than about pH
14.
The concentration of the target material and target material-containing
species can vary
depending on a number of factors. The concentration of either or both can be,
for example,
commonly at least about 5 ppm, more commonly at least about 50 ppm, more
commonly at least
about 100 ppm, more commonly at least about 500 ppm, more commonly at least
about 1,000
ppm, more commonly at least about 5,000 ppm, more commonly at least about
10,000 ppm, and
more commonly at least about 100,000 ppm.
Medium Pre-Treatment
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CA 2832908 2019-01-02
In step 108, the medium 104 is optionally pre-treated to produce a selected
primary
species of the target material. The selected primary species is generally more
effectively
removed by the rare earth-containing composition, additive, and/or particle
than the primary
species in the medium 104. For example, one or more of the Eh and pH values
may be altered
for more effective removal and/or detoxification of the target material. The
primary species of
lead, for instance, is elemental (Pbs) when the Eh is less (more negative)
than about -0.3. By
increasing the Eh and and varying the pH value of the aqueous solution the
primary species of
lead can become one or more of Pb(H20)62+, Pb(H20)5CO3, Pb(H20)4(CO3)22+,
Pb(H20)5(OH)2,
or Pb(H20)2(OH)42-. As will be appreciated, pH is a measure of the activity of
hydrogen ions
while Eh is a measure of the electrochemical (oxidation/reduction) potential.
The type of pre-treatment employed can depend on the application.
In one application, an acid, acid equivalent, base, or base equivalent is
added to adjust the
pH to a desired pH value. Examples of acids or acid equivalents include
monoprotic acids and
polyprotic acids, such as mineral acids, sulfonic acids, carboxylic acids,
vinylogous carboxylic
acids, nucleic acids, and mixtures thereof. Examples of bases and base
equivalents include
strong bases (such as potassium hydroxide, barium hydroxide, cesium hydroxide,
sodium
hydroxide, strontium hydroxide, calcium hydroxide, magnesium hydroxide,
lithium hydroxide,
and rubidium hydroxide), superbases, carbonates, ammonia, hydroxides, metal
oxides
(particularly alkoxides), and counteranions of weak acids.
In one application, oxidation and reduction reactions can be used to adjust
the Eh value.
Eh is a measure of the oxidiation or reduction potential of the medium 104.
The oxidation or
reduction potential is commonly referred to as electromotive force or EMF. The
EMF is
typically measured with respect to a standardized reference electrode. Non-
limiting examples of
standardized reference electrodes are hydrogen electrode (commonly referred to
as SHE), copper
copper sulfate electrode, and silver/silver chloride to name a few.
In one variation, the target material or target material-containing species is
contacted with
an oxidizing agent to oxidize the target material or target material-
containing species. The
oxidizing agent may comprise a chemical oxidizing agent, an oxidation process,
or combination
of both.
A chemical oxidizing agent comprises a chemical composition in elemental or
compounded form. The chemical oxidizing agent accepts an electron from the
target material or
43
CA 2832908 2019-01-02
target material-containing species. In the accepting of the electron, the
oxidizing agent is
reduced to form a reduced form of the oxidizing agent. Non-limiting examples
of preferred
chemical oxidizing agents are chlorine, chloroamines, chlorine dioxide,
hypochlorites,
trihalomethane, haloacetic acid, ozone, hydrogen peroxide, peroxygen
compounds, hypobromous
.. acid, bromoamines, hypobromite, hypochlorous acid, isocyanurates,
tricholoro-s-triazinetriones,
hydantoins, bromochloro-dimethyldantoins, 1-bromo-3-chloro-5,5-
dimethyldantoin, 1,3-
dichloro-5,5-dimethyldantoin, sulfur dioxide, bisulfates, and combinations
thereof. It is further
believed that in some configurations one or more the following chemical
compositions may
oxidize the target material or target material-containing species: bromine,
BrCl, permanganates,
phenols, alcohols, oxyanions, arsenites, chromates, trichloroisocyanuric acid,
and surfactants.
The chemical oxidizing agent may further be referred to as an "oxidant" or an
"oxidizer".
An oxidation process comprises a physical process that alone or in combination
with a
chemical oxidizing agent. The oxidation process removes and/or facilitates the
removal an
electron from the target material or target material-containing species. Non-
limiting examples of
oxidation processes are electromagnetic energy, ultra violet light, thermal
energy, ultrasonic
energy, and gamma rays.
In another variation, the target material or target material-containing
species is contacted
with a reducing agent to reduce the target material or target material-
containing species. The
oxidizing agent may comprise a chemical oxidizing agent, an oxidation process,
or combination
of both.
A chemical reducing agent comprises a chemical composition in elemental or
compounded form. The chemical reducing agent donates an electron to the target
material or
target material-containing species. In the donating the electron, the reducing
agent is oxidized
to form an oxidized form of the oxidizing agent. Non-limiting examples of
preferred chemical
reducing agents are lithium aluminum hydride, nascent (atomic) hydrogen,
sodium amalgam,
sodium borohydride, compounds containing divalent tin ion, sulfite compounds,
hydrazine, zinc-
mercury amalgam, diisobutylaluminum hydride, Lindlar catalyst, oxalic acid,
formic acid,
ascorbic acid, phosphites, hypophosphites, phosphorous acids, dithiothreitols,
and compounds
containing the divalent iron ion. The chemical reducing agent may further be
referred to as a
"reductant" or a "reducer".
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CA 2832908 2019-01-02
A redox process is a physical process that alone or in combination with a
chemical
oxidizing agent transfers electrons to or form a target material or target
material-containing
species. Non-limiting examples of oxidation processes are electromagnetic
energy, ultra violet
light, thermal energy, ultrasonic energy, gamma rays, and biological
processes.
In one variation, the medium is contacted with a halogenated species, such as
chlorine,
bromine, iodine, or an acid, base, or salt thereof. As will be appreciated,
halogens impact the Eh
of the medium. In some configurations, halogens can impact the pH value of the
aqueous media.
Other types of pre-treatment may be employed to remove species from the medium
that
can impair removal of the target material or target material-containing
species and/or adjustment
of the pH and/or Eh of the medium.
The pre-treatment can comprise one or more of clarifying, disinfecting,
coagulating,
aerating, filtering, separating solids and liquids, digesting, and polishing
processes. More
specifically, the pre-treatment process can commonly comprise one of
clarifying, disinfecting,
coagulating, aerating, filtering, separating solids and liquids, digesting,
and polishing processes,
more commonly any two of clarifying, disinfecting, coagulating, aerating,
filtering, separating
solids and liquids, digesting, and polishing processes arranged in any order,
even more
commonly any three of clarifying, disinfecting, coagulating, aerating,
filtering, separating solids
and liquids, digesting, and polishing processes arranged in any order, yet
even more commonly
any four of clarifying, disinfecting, coagulating, aerating, filtering,
separating solids and liquids,
digesting, and polishing processes arranged in any order, still yet even more
commonly any five
of clarifying, disinfecting, coagulating, aerating, filtering, separating
solids and liquids,
digesting, and polishing processes arranged in any order, still yet even more
commonly any six
of clarifying, disinfecting, coagulating, aerating, filtering, separating
solids and liquids,
digesting, and polishing processes arranged in any order, still yet even more
commonly any
seven of clarifying, disinfecting, coagulating, aerating, filtering,
separating solids and liquids,
digesting, and polishing processes arranged in any order, still yet even more
commonly any eight
of clarifying, disinfecting, coagulating, aerating, filtering, separating
solids and liquids,
digesting, and polishing processes arranged in any order, still yet even more
commonly any nine
of clarifying, disinfecting, coagulating, aerating, filtering, separating
solids and liquids,
digesting, and polishing processes arranged in any order, still yet even more
commonly any ten
of clarifying, disinfecting, coagulating, aerating, filtering, separating
solids and liquids,
CA 2832908 2019-01-02
digesting, and polishing processes arranged in any order, still yet even more
commonly any
eleven of clarifying, disinfecting, coagulating, aerating, filtering,
separating solids and liquids,
digesting, and polishing processes arranged in any order, and yet still even
more commonly each
of clarifying, disinfecting, coagulating, aerating, filtering, separating
solids and liquids,
digesting, and polishing process arranged in any order. In some
configurations, the pre-treatment
may comprise or may further comprise processing by one or more of the
additional process
equipment of the water-handling system.
Contact of Medium with Rare Earth-Containing Additive
In step 112, the optionally pre-treated medium is contacted with the rare
earth-containing
composition, additive, or particle or particulate to form a rare earth- and
target material-
containing product. As noted, the rare earth-containingcomposition, additive,
and/or particle or
particulate chemically and/or physically reacts with, sorbs, precipitates,
chemically transforms,
or otherwise deactivates or binds with the target material or target material-
containing species.
In one configuration, the rare earth-containing additive reacts with, sorbs,
precipitates,
chemically transforms, or otherwise deactivates or binds with at least about
25%, more
commonly at least about 50%, more commonly more commonly more than about 50%,
more
commonly at least about 75%, and even more commonly at least about 95% of the
target
material or target material-containing species. The rare earth- and target
material-containing
product includes the rare earth, the target material, and, depending on the
materials involved,
potentially one or more other constituents or components of the rare earth-
containing
composition and/or target material-containing species. While not wishing to be
bound by any
theory, it is believed that the binding mechanism, in some processes, is by
waters of hydration,
hydroxyl radical, hydroxide ion, or carbonate species, compounded, complexed,
or otherwise
attached to the target material acts as a chemical entity that attaches, sorbs
and/or chemically
bonds to the rare earth or rare earth-containing composition.
The temperature of the medium 104, during the contacting step, can vary.
Typically, the
temperature of the aqueous solution can vary during the contacting step. For
example, the
temperature of the aqueous solution can vary depending on the water. Commonly,
the
temperature of the aqueous solution is ambient temperature. Typically, the
solution temperature
ranges from about -5 degrees Celsius to about 50 degrees Celsius, more
typically from about 0
degrees Celsius to about 45 degrees Celsius, yet even more typically from
about 5 degrees
46
CA 2832908 2019-01-02
Celsius to about 40 degrees Celsius and still yet even more typically from
about 10 degrees
Celsius to about 35 degrees Celsius. It can be appreciated that each of the
waters comprising
each of the clarifying, disinfecting, coagulating, aerating, filtering,
separating solids and liquids,
digesting, and polishing processes may include optional processing units
and/or operations that
heat and/or cool one or more of each of the waters. In some configurations,
each of the waters
may be heated to have a temperature of typically at least about 20 degrees
Celsius, more
typically at least about 25 degrees Celsius, even more typically at least
about 30 degrees Celsius,
yet even more typically of at least about 35 degrees Celsius, still yet even
more typically of at
least about 40 degrees Celsius, still yet even more typically of at least
about 45 degrees Celsius,
still yet even more typically of at least about 50 degrees Celsius, still yet
even more typically of
at least about 60 degrees Celsius, still yet even more typically of at least
about 70 degrees
Celsius, still yet even more typically of at least about 80 degrees Celsius,
still yet even more
typically of at least about 90 degrees Celsius, still yet even more typically
of at least about 100
degrees Celsius, still yet even more typically of at least about 110 degrees
Celsius, still yet even
more typically of at least about 120 degrees Celsius, still yet even more
typically of at least about
140 degrees Celsius, still yet even more typically of at least about 150
degrees Celsius, or still
yet even more typically of at least about 200 degrees Celsius. In some
configurations, each of
the waters comprising each of the clarifying, disinfecting, coagulating,
aerating, filtering,
separating solids and liquids, digesting, and polishing processes may be
cooled to have a
temperature of typically of no more than about 110 degrees Celsius, more
typically of no more
than about 100 degrees Celsius, even more typically of no more than about 90
degrees Celsius,
yet even more typically of no more than about 80 degrees Celsius, still yet
even more typically of
no more than about 70 degrees Celsius, still yet even more typically of no
more than about 60
degrees Celsius, still yet even more typically of no more than about 50
degrees Celsius, still yet
even more typically of no more than about 45 degrees Celsius, still yet even
more typically of
no more than about 40 degrees Celsius, still yet even more typically of no
more than about 35
degrees Celsius, still yet even more typically of no more than about 30
degrees Celsius, still yet
even more typically of no more than about 25 degrees Celsius, still yet even
more typically of no
more than about 20 degrees Celsius, still yet even more typically of no more
than about 15
degrees Celsius, still yet even more typically of no more than about 10
degrees Celsius, still yet
47
CA 2832908 2019-01-02
even more typically of no more than about 5 degrees Celsius, or still yet even
more typically of
no more than about 0 degrees Celsius.
Separation of the Rare Earth- and Target Material-Containing Product from
Medium
In optional step 116, the product is removed from the medium 104 to form a
treated
medium 124. In one configuration, commonly at least about 25%, more commonly
at least about
50%, more commonly more commonly more than about 50%, more commonly at least
about
75%, and even more commonly at least about 95% of the rare earth- and target
material-
containing product is removed from the medium. It can be appreciated that, in
such instances,
the product comprises an insoluble material.
The solid rare earth- and target material-containing product may be removed by
any
suitable technique, such as by a liquid/solid separation system. Non-limiting
examples of
liquid/solid separation systems are filtration, floatation, sedimentation,
cyclone, and centrifuging.
Alternatively, the rare earth-containing additive is in the form of a
particulate bed or supported
porous and permeable matrix, such as a filter, through which the media passes.
Alternatively, the rare earth- and target material-containing product
dissolved in the water
may remain in the water in a de-activated form. Non-limiting examples of de-
activated rare
earth- and target material-containing product that may remain dissolved are
environmentally
stable co-ordination complexes of a target material-containing species and the
rare earth-
containing composition.
In accordance with some embodiments, the treated medium 124 has a lower
content of at
least one target material compared to the target material-containing medium
104. Commonly,
the treated medium 124 content is at least about 0.9 of the medium target
material-containing
medium 104, more commonly the treated medium 124 content is at least about 0.8
of the
medium target material-containing medium 104, even more commonly the treated
medium 124
content is at least about 0.7 of the target material-containing medium 104,
yet even more
commonly the treated medium 124 content is at least about 0.6 of the target
material-containing
medium 104, still yet even more commonly the treated medium 124 content is at
least about 0.5
of the target material-containing medium 104, still yet even more commonly the
treated medium
124 content is at least about 0.4 of the target material-containing medium
104, still yet even more
commonly the treated medium 124 content is at least about 0.3 of the target
material-containing
medium 104, still yet even more commonly the treated medium 124 content is at
least about 0.2
48
CA 2832908 2019-01-02
of the target material-containing medium 104, still yet even more commonly the
treated medium
124 content is at least about 0.1 of the target material-containing medium
104, still yet even more
commonly the treated aqueous media 124 content is at least about 0.05 of the
target material-
containing medium 104, still yet even more commonly the treated medium 124
content is at least
about 0.01 of the target material-containing medium 104, still yet even more
commonly the
treated 124 content is at least about 0.005 of the target material-containing
medium 104, still yet
even more commonly the treated medium 124 content is at least about 0.001 of
the target
material-containing medium 104, still yet even more commonly the treated
medium 124 content
is at least about 0.5 of the target material-containing medium 104, still yet
even more commonly
the treated medium 124 content is at least about 0.0005 of the target material-
containing medium
104, still yet even more commonly the treated medium 124 content is at least
about 0.0001 of the
target material-containing medium 104, still yet even more commonly the
treated medium 124
content is at least about 5x105 of the target material-containing medium 104,
still yet even more
commonly the treated medium 124 content is at least about 1x10-5 of the target
material-
containing medium 104, still yet even more commonly the treated medium 124
content is at least
about 5x10-6 of the target material-containing medium 104, and still yet even
more commonly
the treated medium 124 content is at least about 1x10-6 of the target material-
containing medium
104. Typically, the target material content in the treated medium 124 content
is no more than
about 100,000 ppm, more typically the target material content in the treated
medium 124 content
is no more than about 10,000 ppm, even more typically the target material
content in the treated
medium 124 content is no more than about 1,000 ppm, yet even more typically
the target
material content in the treated medium 124 content is no more than about 100
ppm, still yet even
more typically the target material content in the treated medium 124 content
is no more than
about 10 ppm, still yet even more typically the target material content in the
treated medium 124
content is no more than about 1 ppm, still yet even more typically the target
material content in
the treated medium 124 content is no more than about 100 ppb, still yet even
more typically the
target material content in the treated medium 124 content is no more than
about 10 ppb, still yet
even more typically the target material content in the treated medium 124
content is no more
than about 1 ppb, and yet still even more typically the target material
content in the treated
medium 124 content is no more than about 0.1 ppb.
Step 116 can include optional treatment steps.
49
CA 2832908 2019-01-02
The treatment can comprise one or more of clarifying, disinfecting,
coagulating, aerating,
filtering, separating solids and liquids, digesting, and polishing processes.
More specifically, the
treatment process can commonly comprise one of clarifying, disinfecting,
coagulating, aerating,
filtering, separating solids and liquids, digesting, and polishing, more
commonly any two of
clarifying, disinfecting, coagulating, aerating, filtering, separating solids
and liquids, digesting,
and polishing arranged in any order, even more commonly any three of
clarifying, disinfecting,
coagulating, aerating, filtering, separating solids and liquids, digesting,
and polishing arranged in
any order, yet even more commonly any four of clarifying, disinfecting,
coagulating, aerating,
filtering, separating solids and liquids, digesting, and polishing arranged in
any order, still yet
even more commonly any five of clarifying, disinfecting, coagulating,
aerating, filtering,
separating solids and liquids, digesting, and polishing arranged in any order,
still yet even more
commonly any six of clarifying, disinfecting, coagulating, aerating,
filtering, separating solids
and liquids, digesting, and polishing arranged in any order, still yet even
more commonly any
seven of clarifying, disinfecting, coagulating, aerating, filtering,
separating solids and liquids,
digesting, and polishing arranged in any order, still yet even more commonly
any eight of
clarifying, disinfecting, coagulating, aerating, filtering, separating solids
and liquids, digesting,
and polishing arranged in any order, still yet even more commonly any nine of
clarifying,
disinfecting, coagulating, aerating, filtering, separating solids and liquids,
digesting, and
polishing arranged in any order, still yet even more commonly any ten of
clarifying, disinfecting,
coagulating, aerating, filtering, separating solids and liquids, digesting,
and polishing arranged in
any order, still yet even more commonly any eleven of clarifying,
disinfecting, coagulating,
aerating, filtering, separating solids and liquids, digesting, and polishing
arranged in any order,
and yet still even more commonly each of clarifying, disinfecting,
coagulating, aerating,
filtering, separating solids and liquids, digesting, and polishing arranged in
any order.
Regeneration of Rare Earth in Rare Earth- and Target Material-Containing
Product for Recycle
The separated rare earth- and target material-containing product may be
subjected to
suitable processes for removal of the target material from the rare earth to
enable the rare earth to
be recycled to step 112. Regeneration processes include, for example,
desorbtion, oxidation,
reduction, thermal processes, irradiation, and the like.
CA 2832908 2019-01-02
As used herein cerium (III) may refer to cerium (+3), and cerium (+3) may
refer to
cerium (III). As used herein cerium (IV) may refer to cerium (+4), and cerium
(+4) may refer to
cerium (IV).
EXAMPLES
The following examples are provided to illustrate certain embodiments and are
not to be
construed as limitations on the embodiments, as set forth in the appended
claims. All parts and
percentages are by weight unless otherwise specified.
Example 1
A set of tests were conducted to determine a maximum arsenic loading capacity
of
soluble cerium (III) chloride CeC13 in an arsenic-containing stream to reduce
the arsenic
concentration to less than 50 ppm. As shown by Table 1, arsenic-containing
streams (hereinafter
alkaline leach solutions) tested had the following compositions:
Table 1
Test Volume Na2CO3 Na2SO4 Na2HAs04-7H20 As g/L
Number of DI (g) (g) (g)
(mL)
1 500 10 8.875 1.041 0.5
2 500 10 8.875 2.082 1
3 500 10 8.875 4.164 2
4 500 10 8.875 6.247 3
5 500 10 8.875 8.329 4
6 500 10 8.875 10.411 5
7 500 10 8.875 12.493 6
The initial pH of the seven alkaline leach solutions was approximately pH 11,
the
temperatures of the solutions were approximately 70 to 80 C, and the reaction
times were
approximately 30 minutes.
Seven alkaline leach solutions were made with varying arsenic (V)
concentrations, which
can be seen in Table 1 above. Each solution contained the same amount of
sodium carbonate (20
g/L) and sodium sulfate (17.75 g/L). In a first series of tests, 3.44 mL of
cerium chloride
(CeCI3) were added to every isotherm and equates to 0.918 g Ce02
(approximately 0.05 mole
Ce) In a second series of tests, 6.88 mL of cerium chloride was added to every
test and equates
51
CA 2832908 2019-01-02
to 1.836 g Ce02 (approximately 0.1 mole Ce). Below is the guideline on how
each isotherm test
was performed.
In a first step, 200 mL of solution were measured out by weight and
transferred into a 400
mL Pyrex beaker. The beaker was then placed on hot/stir plate and heated to 70-
80 C while
being stirred.
In a second step, 3.44 mL of cerium chloride were measured out, by weight, and
poured
into the mixing beaker of hot alkaline leach solution. Upon the addition of
cerium chloride, a
white precipitate formed instantaneously. To ensure that the white precipitate
was not cerium
carbonate [Ce2(CO3)3 = xf120], step three was performed.
In the third step, 4.8 mL of concentrated HC1 were slowly added dropwise.
Fizzing was
observed. The solution continued to mix for 30 minutes and was then allowed to
cool for 4
hours before sampling.
The results are shown in Table 2:
Analysis using ICP-AES
Table 2
Approximate
Molar Final As Arsenic Loading Percent
Moles of Arsenic
Ratio Concentration Removed Capacity Arsenic
Cerium (g/L)
(Cc/As) (mg,/L) (mg) (mg/g) Removed
Added
0.5 4.2 0 100 104 100
1.0 2.1 8 199 206 99
2.0 1.0 159 367 380 92
0.005 3.0 0.7 903 412 426 69
4.0 0.5 1884 408 422 51
5.0 0.4 2663 445 461 45
6.0 0.4 3805 409 422 34
0.5 8.3 0 102 53 100
1.0 4.2 0 201 104 100
2.0 2.1 55 388 201 97
0.01 3.0 1.4 109 577 299 96
4.0 1.1 435 709 367 89
5.0 0.8 1149 759 392 76
6.0 0.7 1861 810 419 67
Fig. 48 shows that the loading capacity begins to level off at the theoretical
capacity of
436 mg/g if cerium arsenate (CeAs04) was formed, leading one to believe it was
formed. Fig.
52
CA 2832908 2019-01-02
49 displays that the molar ratio of cerium to arsenic required to bring down
the arsenic
concentration to less than 50 ppm lies somewhere between a 1 molar and 2 molar
ratio.
However, at a 2 molar ratio a loading capacity of 217 was achieved. Fig. 50
shows very similar
results (essentially double the addition of CeC13); at a molar ratio between 1
and 2, the dissolved
arsenic concentration can be below 50 ppm. This capacity may be improved with
a lower molar
ratio and tighter pH control.
Example 2
In this example, the product of cerium and arsenic was shown to contain more
arsenic
than would be anticipated based upon the stoichiometry of gasparite, the
anticipated product of
cerium and arsenic. Furthermore, the X-ray diffraction pattern suggests that
the product is
amorphous or nanocrystalline and is consistent with ceria or, possibly,
gasparite. The amorphous
or nanocrystalline phase not only permits the recycling of process water after
arsenic
sequestration but does so with a far greater arsenic removal capacity than is
observed from other
forms of cerium addition, decreasing treatment costs and limiting
environmental hazards.
Eight 50 mL centrifuge tubes were filled with 25 mL each of a fully oxidized
solution of
arsenate/sulfate/NaOH while another eight 50 mL centrifuge tubes were filled
with 25 mL each
of a fully reduced solution of arsenite/sulfide/NaOH that had been sparged
with molecular
oxygen for 2 hours. Both solutions contained 24 g/L arsenic, 25 g/L NaOH, and
the equivalent
of 80 g/L sulfide. Each sample was then treated with either cerium (IV)
nitrate or cerium (III)
chloride. The cerium salt solutions were added in doses of 1, 2, 3, or 5 mL.
No pH adjustments
were made, and no attempt was made to adjust the temperature from ambient 22
C.
Fifteen of sixteen test samples showed the rapid formation of a precipitate
that occupied
the entire ¨ 25 mL volume. The reaction between the two concentrated solutions
took place
almost immediately, filling the entire solution volume with a gel-like
precipitate. The sixteenth
sample, containing 5 mL of cerium (IV) remained bright yellow until an
additional 5 mL of 50%
NaOH was added, at which point a purple solid formed.
Solids formed from the reaction of cerium and arsenic were given an hour to
settle with
little clarification observed. The samples were then centrifuged at 50% speed
for 5 minutes. At
this point, the total volume of the solution and the volume of settled solids
were recorded, and a
5 mL sample was collected for analysis. Since little more than 5 mL of
supernatant solution was
available (the concentration of arsenic was 24 g/L, meaning that the
concentration of cerium was
53
CA 2832908 2019-01-02
also quite elevated), the samples were filtered using 0.45 micron papers. The
four samples with
mL of cerium salt added were not filtered. The supernatant solutions were
collected and the
volume recorded.
The filter cake from the reaction was left over the weekend in plastic weight
boats atop a
5 drying oven. Seventy-two hours later, the content of each boat was
weighed, and it was
determined that the pellets were still very moist (more mass present than was
added to the
sample as dissolved solids). The semi-dry solids of the samples with 2 mL of
cerium salt
solution were transferred to a 130 C drying oven for one hour, then analyzed
by XRD.
The XRD results are shown in Fig. 51. XRD results are presented for gasparite
(the
expected product) and the various systems that were present during the
experiments, with "ceria"
corresponding to cerium dioxide. As can be seen from Fig. 51, the XRD analysis
did not detect
any crystalline peaks or phases of arsenic and cerium solids in the various
systems. The only
crystalline material present was identified as either NaCl, NaNO3 (introduced
with the rare earth
solutions) or Na2SO4 that was present in the samples prepared from Na2SO4.
However, the
broad diffraction peaks at about 29, 49, and 57 degrees 2-Theta could be
indicative of very small
particles of ceria or, possibly, gasparite.
The arsenic content of supernatant solutions was measured using ICP-AES. It
was
observed that both cerium (IV) and cerium (III) effectively removed arsenic
from the system to
about the same extent. As can be seen from Table 3 below and Fig. 52, a
greater difference in
arsenic removal was found between the fully oxidized system, and the system
which was fully
reduced before molecular oxygen sparging. Fig. 52 shows a plot for arsenic
micromoles
removed in an "oxidized" system staring with arsenate and a "molecular oxygen
sparged" system
starting with arsenite, which was subsequently oxidized to arsenate through
molecular oxygen
sparging.
54
CA 2832908 2019-01-02
Table 3
Arsenite/sulfide/NaOH + 02 Arsenate/sulfate/NaOH
Cerium Additive mL Ce Ce02 As ppm As capacity
As ppm As
(g) (mg/g) capacity
(mg/g)
cerium (III) chloride 1 0.33 21200 242 20000 276
2 0.65 18800 271 8700 576
3 0.98 11200 324 1000 596
cerium (IV) nitrate 1 0.26 21600 265 19200 429
2 0.52 18800 237 8000 764
3 0.77 13600 322 3200 672
control 0 0.0 25200 24400
Fig. 52 shows the amount of arsenic consumed by the formation of precipitated
solids,
plotted as a function of the amount of cerium added. The resultant soluble
arsenic concentrations
from this experiment can be divided into two groups: samples containing fully
oxidized arsenate
and sulfate and samples containing arsenite and sulfite that was sparged with
molecular oxygen.
The oxidation state of the cerium used as the soluble fixing agent had
considerably less impact
on the efficacy of the process, allowing both Ce(III) and Ce(IV) data to be
fit with a single
regression line for each test solution. In the case of the fully oxidized
solution, arsenic
sequestration with the solids increases in an arsenic to cerium molar ratio of
1:3, potentially
making a product with a stoichiometry of Ce3As4.
Example 3
A series of experiments were performed, the experiments embody the
precipitation of
arsenic, in the As (V) state, from a highly concentrated waste stream of pH
less than pH 2 by the
addition of a soluble cerium salt in the Ce (III) state followed by a
titration with sodium
hydroxide (NaOH) solution to a range of between pH 6 and pH 10.
In a first test, a 400 mL solution containing 33.5 mL of a 0.07125 mol/L
solution of
NaH2As04 was stirred in a beaker at room temperature. The pH was adjusted to
roughly pH 1.5
by the addition of 4.0 mol/L HNO3, after which 1.05 g of Ce(NO3)3 = 6 H20 was
added. No
CA 2832908 2019-01-02
change in color or any precipitate was observed upon the addition of the
cerium (III) salt. NaOH
(1.0 mol/L) was added to the stirred solution at a dropwise pace to bring the
pH to pH 10.1. The
pH was held at pH 10.2 0.2 for a period of 1.5 hours under magnetic stir.
After the reaction,
the solution was removed from the stir plate and allowed to settle undisturbed
for 12 to 18 hours.
The supernatant was decanted off and saved for ICP-MS analysis of Ce and As.
The solids were
filtered through a 0.4 gm cellulose membrane and washed thoroughly with 500 to
800 mL of de-
ionized water. The solids were air-dried and analyzed by X-ray diffraction.
In a second test, a simulated waste stream solution was prepared with the
following
components: As (1,200 ppm), F (650 ppm), Fe (120 ppm), S (80 ppm), Si (50
ppm), Ca (35
ppm), Mg (25 ppm), Zn (10 ppm), and less than 10 ppm of Al, K, and Cu. The pH
of the
solution was titrated down to pH 0.4 with concentrated HC1 (12.1 mol/L), and
the solution was
heated to 70 C. A solution of CeC13 (6.3 mL, 1.194 mol/L) was added to the hot
solution, and
the pH was slowly increased to pH 7.5 by dropwise addition of NaOH (20 wt. %,
6.2 mol/L).
The solution was then allowed to age at 70 C under magnetic stirring for 1.5
hours, holding pH
at pH 7.5 + 0.2. The solution was then removed from the heat and allowed to
settle undisturbed
for 12 to 18 hours. The supernatant was decanted off and saved for ICP-MS
analysis of Ce and
As. The precipitated solids were centrifuged and washed twice before being
filtered through a
0.4 gm cellulose membrane and washed thoroughly with 500 to 800 mL of de-
ionized water.
The solids were air-dried and analyzed by X-ray diffraction.
In a third test, solid powders of the novel Ce-As compound were tested for
stability in a
low-pH leach test. 0.5 g of the novel Ce-As compound were added to 10 mL of an
acetic acid
solution with a pH of either pH 2.9 or pH 5Ø The container was sealed and
rotated for 18 2
hours at 30 2 revolutions per minute at an ambient temperature in the range
of 22 5 C. After
the required rotation time, the solution was filtered through a 0.2 micron
filter and analyzed by
ICP-MS for Ce and As which may have been leached from the solid. Less than 1
ppm of As was
detected by ICP-MS.
Fig. 53 compares the X-Ray Diffraction ("XRD") results for the novel Ce-As
compound
(shown as trigonal CeAs 04 = (H20)x (both experimental and simulated) and
gasparite (both
experimental and simulated). Fig. 9 compares the XRD results for trigonal CeAs
04 = (H2O)
(both experimental and simulated) and trigonal BiP 04 = (H20)0.67 (simulated).
The XRD results
show that the precipitated crystalline compound is structurally different from
gasparite
56
CA 2832908 2019-01-02
(CeAs04), which crystallizes in a monoclinic space group with a monazite-type
structure, and is
quite similar to trigonal BiP 04 = (H20)0.67.
Experiments with different oxidation states of Ce and As demonstrate that the
novel Ce ¨
As compound requires cerium in the Ce (III) state and arsenic in the As(V)
state. pH titration
with a strong base, such as sodium hydroxide, seems to be necessary. As pH
titration with
sodium carbonate produces either gasparite, a known and naturally occurring
compound or a
combination of gasparite and trigonal CeAs04 = (H20)x. The use of cerium
chloride and cerium
nitrate both successfully demonstrated the successful synthesis of the novel
compound. The
presence of other metal species, such as magnesium, aluminum, silicon,
calcium, iron, copper,
and zinc, have not been shown to inhibit the synthesis of the novel compound.
The presence of
fluoride will compete with arsenic removal and produce an insoluble CeF3
precipitate. Solutions
containing only arsenic and cerium show that a Ce:As atomic ratio of 1:1 is
preferable for
forming the novel compound, and solutions containing excess cerium have
produced a cerium
oxide (Ce02) precipitate in addition to the novel compound. Additionally, the
novel compound
appears to be quite stable when challenged with a leach test requiring less
than 1 ppm arsenic
dissolution in solution of pH 2.9 and pH 5Ø
Example 4
In this Example, a test solution containing 1.0 ppmw chromium calculated as Cr
was
prepared by dissolving reagent grade potassium dichromate in distilled water.
This solution
.. contained Cr' in the form of oxyanions and no other metal oxyanions. A
mixture of 0.5 gram of
lanthanum oxide (La203) and 0.5 gram of cerium dioxide (Ce02) was slurried
with 100
milliliters of the test solution in a glass container. The resultant slurries
were agitated with a
Teflon coated magnetic stir bar for 15 minutes. After agitation the water was
separated from the
solids by filtration through Whatman #41 filter paper and analyzed for
chromium using an
inductively coupled plasma atomic emission spectrometer. This procedure was
repeated twice,
but instead of slurrying a mixture of lanthanum oxide and cerium dioxide with
the 100 milliliters
of test solution, 1.0 gram of each was used. The results of these tests 1-3
are set forth below in
Table 4.
57
CA 2832908 2019-01-02
Table 4
Oxyanion in Water Oxyanion in Oxyanion
Example Before Test Slurried Water After Removed
Number Element (ppmw) Material Test (ppmw) (percent)
0.5 gm La203
1 Cr 1.0 0.5 gm Ce02 50.013 -98.7
2 Cr 1.0 1.0 gm Ce02 50.001 99.9
3 Cr 1.0 1.0 gm La203 50.015 ?'-98.5
0.5 gm La203
4 Sb 1.0 0.5 gm Ce02 50.016 98.4
Sb 1.0 1.0 gm Ce02 -50.016 -98.4
6 Sb 1.0 1.0 gm La203 '50.100 90.0
0.5 gm La203
7 Mo 1.0 0.5 gm Ce02 50.007 -99.3
8 Mo 1.0 1.0 gm Ce02 -50.001 --99.9
9 Mo 1.0 1.0 gm La203 50.009 99.1
1.0 gm La203
V 1.0 1.0 gm Ce02 '5-0.004 .99.6
11 V 1.0 1.0 gm Ce02 0.120 88.0
12 V 1.0 1.0 gm La203 -50.007 .99.3
0.5 gm La203
13 U 2.0 0.5 gm Ce02 -50.017 98.3
14 U 2.0 1.0 gm Ce02 0.500 75.0
U 2.0 1.0 gm La203 -50.050 95.0
0.5 gm La203
16 W 1.0 0.5 gm Ce02 50.050 95.0
17 W 1.0 1.0 gm Ce02 .-0.050 95.0
18 W 1.0 1.0 gm La203 5-0.050 -95.0
As can be seen the lanthanum oxide, the cerium dioxide and the equal mixture
of each
were effective in removing over 98 percent of the chromium from the test
solution.
5 Tests 4-6
The procedures of Tests 1-3 were repeated except that a test solution
containing 1.0
ppmw antimony calculated as Sb was used instead of the chromium test solution.
The antimony
test solution was prepared by diluting with distilled water a certified
standard solution containing
100 ppmw antimony along with 100 ppmw each of As, Be, Ca, Cd, Co, Cr, Fe, Li,
Mg, Mn, Mo,
10 Ni, Pb, Se, Sr, Ti, TI, V, and Zn. The results of these tests are also
set forth in Table 4 and show
that the two rare earth compounds alone or in admixture were effective in
removing 90 percent
or more of the antimony from the test solution.
Tests 7-9
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The procedures of Tests 1-3 were repeated except that a test solution
containing 1.0
ppmw molybdenum calculated as Mo was used instead of the chromium test
solution. The
molybdenum test solution was prepared by diluting with distilled water a
certified standard
solution containing 100 ppmw molybdenum along with 100 ppmw each of As, Be,
Ca, Cd, Co,
Cr, Fe, Li, Mg, Mn, Ni, Pb, Sb, Se, Sr, Ti, 11, V, and Zn. The results of
these tests are set forth in
Table 4 and show that the lanthanum oxide, the cerium dioxide and the equal
weight mixture of
each were effective in removing over 99 percent of the molybdenum from the
test solution.
Tests 10-12
The procedures of Tests 1-3 were repeated except that a test solution
containing 1.0
ppmw vanadium calculated as V was used instead of the chromium test solution.
The vanadium
test solution was prepared by diluting with distilled water a certified
standard solution containing
100 ppmw vanadium along with 100 ppmw each of As, Be, Ca, Cd, Co, Cr, Fe, Li,
Mg, Mn, Mo,
Ni, Pb, Sb, Se, Sr, Ti, Tl, and Zn. The results of these tests are set forth
in Table 4 and show that
the lanthanum oxide and the equal weight mixture of lanthanum oxide and cerium
dioxide were
effective in removing over 98 percent of the vanadium from the test solution,
while the cerium
dioxide removed about 88 percent of the vanadium.
Tests 13-15
The procedures of Tests 1-3 were repeated except that a test solution
containing 2.0
ppmw uranium calculated as U was used instead of the chromium test solution.
The uranium test
solution was prepared by diluting a certified standard solution containing
1,000 ppmw uranium
with distilled water. This solution contained no other metals. The results of
these tests are set
forth in Table 4 and show that, like in Tests 10-12, the lanthanum oxide and
the equal weight
mixture of lanthanum oxide and cerium dioxide were effective in removing the
vast majority of
the uranium from the test solution. However, like in those examples, the
cerium dioxide was not
as effective removing about 75 percent of the uranium.
Tests 16-18
The procedures of Tests 1-3 were repeated except that a test solution
containing 1.0
ppmw tungsten calculated as W was used instead of the chromium test solution.
The tungsten
test solution was prepared by diluting a certified standard solution
containing 1,000 ppmw
tungsten with distilled water. The solution contained no other metals. The
results of these tests
are set forth in Table 4 and show that the lanthanum oxide, cerium dioxide,
and the equal weight
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mixture of lanthanum oxide and cerium dioxide were equally effective in
removing 95 percent or
more of the tungsten from the test solution.
Example 5
This example demonstrates the affinity of halogens for rare earth metals. A
series of tests
were performed to determine if certain halogens, particularly fluoride (and
other halogens),
compete with the binding of arsenic to cerium chloride. Arsenic is known to
bind strongly to
cerium chloride in an aqueous medium when using water soluble cerium chloride
(CeC13). This
halogen binding affinity was determined by doing a comparison study between a
stock solution
containing fluoride and one without fluoride. Materials used were: CeC13
(1.194 M Ce or
205.43 g/L (Rare Earth Oxide or REO) and 400 mL of the stock. The constituents
of the stock
solution, in accordance with NSF P231 "general test water 2" ("NSF"), are
shown in Tables 5
and 6:
Table 5.
Amount of Reagents Added
Amount of
Amount of
Reagent Added to
Compound Reagent Added
3
to 3.5L (9) .5L (g) No
Fluoride
NaF 5.13 0
AICI3 = 6H20 0.13 0.13
CaC12 = 2 H20 0.46 0.46
CuSO4 = 5H20 0.06 0.06
FeSO4 = 7H20 2.17 2.16
KCI 0.16 0.15
MgCl2. 6H20 0.73 0.74
Na2Si 03 = 9H20 1.76 1.76
ZnSO4 = 7H20 0.17 0.17
Na2HAs04 = 7H20 18.53 18.53
Table 6.
Calculated Analyte Concentration
Element Theoretical Concentration Theoretical
(gm/L) Concentration
(mg/L) No
Fluoride
Cl 19032 15090
Na 1664 862
24 22
Cu 4 4
Fe 125 124
Zn 11 11
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As 1271 1271
Mg 25 20
Ca 36 36
Al 16 16
Si 50 50
79 79
663 0
The initial pH of the stock solution was pH approximately 0-1. The temperature
of the
stock solution was elevated to 70 C. The reaction or residence time was
approximately 90
minutes.
The procedure for precipitating cerium arsenate with and without the presence
of fluorine
is as follows:
Step 1:
Two 3.5L synthetic stock solutions were prepared, one without fluorine and one
with
fluorine. Both solutions contained the compounds listed in Table 5.
Step 2:
400 mL of synthetic stock solution was measured gravimetrically (402.41g) and
transferred into a 600 mL Pyrex beaker. The beaker was then placed on hot/stir
plate and was
heated to 70 C while being stirred.
Step 3:
Enough cerium chloride was added to the stock solution to meet a predetermined
molar
ratio of cerium to arsenic. For example, to achieve a molar ratio of one ceria
mole to one mole
of arsenic 5.68 mL of cerium chloride was measure gravimetrically (7.17g) and
added to the
stirring solution. Upon addition of cerium chloride a yellow/white precipitate
formed
instantaneously, and the pH dropped due to the normality of the cerium
chloride solution being
0.22. The pH was adjusted to approximately 7 using 20% sodium hydroxide.
Step 4:
Once the cerium chloride was added to the 70 C solution, it was allowed to
react for 90
minutes before being sampled.
Step 5:
Repeat steps 2-4 for all desired molar ratios for solution containing fluoride
and without
fluoride.
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The results are presented in Table 7 and Figures 55 and 56.
Table 7. The residual arsenic concentration in supernatant solution after
precipitation
with cerium chloride solution.
Table 7
Residual As Concentration w/
Residual As Concentration no
Molar Ratio
Fluoride Present (mg/L) Fluoride Present (mg/L)
1.00 578 0
1.10 425 0
1.20 286 0
1.30 158.2 0
1.40 58.1 0
1.50 13.68 0
1.60 3.162 0
1.71 0 0
1.81 10.2 0
1.90 0 0
2.01 0 0
A comparison of loading capacities for solutions containing or lacking
fluoride shows a
strong affinity for halogens and halogenated compounds. Figure 55 shows the
affinity of cerium
III for fluoride in the presence of arsenic. Figure 56 shows that the loading
capacities (which is
defined as mg of As per gram of Ce02) for solutions lacking fluoride are
considerably higher at
low molar ratios of cerium to arsenic. Sequestration of fluorinated organic
compounds,
particularly fluorinated pharmaceutical compounds, using rare earth metals,
and particularly
cerium, is clearly indicated.
Solutions with a cerium to arsenic molar ratio of approximately 1.4 to 1 or
greater had a
negligible difference in the loading capacities between solution that
contained F- and not having
This leads one to believe that an extra 40% cerium was needed to sequester the
F-; then the
remaining cerium could react with the arsenic.
These results confirm that the presence of fluoride effectively competes with
the
sequestration of arsenic and other target materials. The interference comes
from the competing
reaction forming CeF3; this reaction has a much more favorable Ksp. In light
of these results,
fluorine and other halogens should be removed prior to addition of the rare
earth-containing
additive.
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Example 6
This example demonstrates the successful removal of sulfate-containing
compounds,
halogenated compounds, carbonate-containing compounds, and phosphate-
containing
compounds, using a cerium dioxide powder. A cerium powder, having a 400 ppb
arsenic
removal capacity, was contacted with various solutions containing arsenic
(III) as arsenite and
arsenic (V) as arsenate and elevated concentrations of the compounds that
compete for the
known binding affinity between arsenic and cerium. The competing organic
compounds included
sulfate ions, fluoride ions, chloride ions, carbonate ions, silicate ions, and
phosphate ions at
concentrations of approximately 500% of the corresponding NSF concentration
for the ion. The
cerium dioxide powder was further contacted with arsenic-contaminated
distilled and NSF P231
"general test water 2" ("NSF") water. Distilled water provided the baseline
measurement.
The results are presented in Fig. 55. As can be seen from Fig. 55, the ions in
NSF water
caused, relative to distilled water, a decreased cerium dioxide capacity for
both arsenite and
arsenate, indicating a successful binding of these compounds to the rare earth
metal. The
presence of carbonate ion decreased the cerium dioxide removal capacity for
arsenate more than
arsenite. The presence of silicate ion decreased substantially cerium dioxide
removal capacities
for both arsenite and arsenate. Finally, phosphate ion caused the largest
decrease in cerium
dioxide removal capacities for arsenite (10X NSF concentration) and arsenate
(50X NSF
concentration), with the largest decrease in removal capacity being for
arsenite.
Example 7
A number of tests were undertaken to evaluate solution phase or soluble cerium
ion
precipitations.
Test 1:
Solutions containing 250 ppm of Cr(VI) were amended with a molar equivalent of
cerium
supplied as either Ce(III) chloride or Ce(IV) nitrate. The addition of Ce(III)
to chromate had no
immediate visible effect on the solution, however 24 hours later there
appeared to be a fine
precipitate of dark solids. In contrast, the addition of Ce(IV) led to the
immediate formation of a
large amount of solids.
As with the previous example, aliquots were filtered, and the pH adjusted to
pH 3 for
Ce(IV) and pH 5 for Ce(III). The addition of Ce(III) had a negligible impact
on Cr solubility,
however Ce(IV) removed nearly 90% of the Cr from solution at pH 3.
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Test 2:
Solutions containing 50 ppm of molybdenum Spex ICP standard, presumably
molybdate,
were amended with a molar equivalent of Ce(III) chloride. As with previous
samples, a solid
was observed after the cerium addition and an aliquot was filtered through a
0.45 micron syringe
filter for ICP analysis. At pH 3, nearly 30 ppm Mo remained in solution, but
as pH was
increased to 5, the Mo concentration dropped to 20 ppm, and near pH 7 the Mo
concentration
was shown to be only 10 ppm.
Example 8
These examples examined the adsorption and desorption of a series of non-
arsenic anions
using methods analogous to those established for the arsenic testing.
Permanganate:
Two examples were performed. In the first example, 40 g of ceria powder were
added to
250 mL of 550 ppm KMnO4 solution. In the second example, 20 g of ceria powder
were added
to 250 mL of 500 ppm KMnat solution and pH was lowered with 1.5 mL of 4 N HC1.
Lowering
the slurry pH increased the Mn loading on ceria four fold.
In both examples the ceria was contacted with permanganate for 18 hours then
filtered to
retain solids. The filtrate solutions were analyzed for Mn using ICP-AES, and
the solids were
washed with 250 mL of DI water. The non-pH adjusted solids were washed a
second time.
Filtered and washed Mn-contacted solids were weighed and divided into a series
of three
extraction tests and a control. These tests examined the extent to which
manganese could be
recovered from the ceria surface when contacted with 1 N NaOH, 10% oxalic
acid, or 1 M
phosphate, in comparison to the effect of DI water under the same conditions.
The sample of permanganate-loaded ceria powder contacted with water as a
control
exhibited the release of less than 5% of the Mn. As with arsenate, NaOH
effectively promoted
desorption of permanganate from the ceria surface. This indicates that the
basic pH level, or
basification, acts as an interferer to permanganate removal by ceria. In the
case of the second
example, where pH was lowered, the effect of NaOH was greater than in the
first case where the
permanganate adsorbed under higher pH conditions.
Phosphate was far more effective at inducing permanganate desorption than it
was at
inducing arsenate desorption. Phosphate was the most effective desorption
promoter we
examined with permanganate. In other words, the ability of the ceria powder to
remove
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permanaganate in the presence of phosphate appears to be relatively low as the
capacity of the
ceria powder for phosphate is much higher than for permanganate.
Oxalic acid caused a significant color change in the permanganate solution,
indicating
that the Mn(VII) was reduced, possibly to Mn(II) or Mn(IV), wherein the
formation of MnO or
MnO2 precipitates would prevent the detection of additional Mn that may or may
not be removed
from the ceria. A reductant appears therefore to be an interferer to ceria
removal of Mn(VII). In
the sample that received no pH adjustment, no desorbed Mn was detected.
However, in the
sample prepared from acidifying the slurry slightly a significant amount of Mn
was recovered
from the ceria surface.
Chromate
250 mL of solution was prepared using 0.6 g sodium dichromate, and the
solution was
contacted with 20 g of cerium powder for 18 hours without pH adjustment. The
slurry was
filtered and the solids were washed with DI water then divided into 50 mL
centrifuge tubes to
test the ability of three solutions to extract chromium from the ceria
surface.
Ceria capacity for chromate was significant and a loading of > 20 mg Cr / g
ceria was
achieved without any adjustments to pH or system optimization (pH of filtrate
was
approximately 8). Likewise, the extraction of adsorbed chromate was also
readily accomplished.
Raising the pH of the slurry containing chromate-laden ceria using 1 N NaOH
was the most
effective method of desorbing chromium that was tested. Considerably less
chromate was
desorbed using phosphate and even less was desorbed using oxalic acid. This
indicates that
phosphate and oxalic acid are not as strong interferers to chromate removal
when compared to
permanganate removal. In the control sample, only 5% of the chromate was
recovered when the
loaded solid was contacted with distilled water.
Antimony
The solubility of antimony is rather low and these reactions were limited by
the amount
of antimony that could be dissolved. In this case, 100 mg of antimony (III)
oxide was placed
into 1 L of distilled water with 10 mL concentrated HCl, allowed several days
to equilibrate, and
was filtered through a 0.8 micron polycarbonate membrane to remove undissolved
antimony.
The liter of antimony solution was contacted with 16 g of ceria powder, which
was effective
removing antimony from solution, but had too little Sb(III) available to
generate a high loading
on the surface. In part due to the low surface coverage and strong surface-
anion interactions, the
CA 2832908 2019-01-02
extraction tests revealed little Sb recovery. Even the use of hydrogen
peroxide, which would be
expected to convert Sb(III) to a less readily adsorbed species of Sb(V), did
not result in
significant amounts of Sb recovery.
Arsenic
Tables 8-11 show the test parameters and results.
Table 8: Loading of cerium oxide surface with arsenate and arsenite for the
demonstration of arsenic desorbing technologies.
Table 8
A B C D E F G H I J K L M
[As] Mass pH Resid As- Wet Wet Dry % Rinse Rinse Final
(g/L) Ce02 [As] loading Mass mass (g) Solids Vol [As] [As]
(g) (ppm) (mg/g) (mL) (ppm) (mg/g)
As 2.02 40.0 9.5 0 50.5 68 7.48 4.63 61.9 250 0 50.5
(III)
As 1.89 40.0 5 149 43.5 69 8.86 5.33 60.2 250 163 42.5
(V)
Table 9: Loading of cerium oxide surface with arsenate and arsenite for the
demonstration of
arsenic desorbing technolo_gies.
[As] Residual As-loading Rinse [As] Final [As]
(g/L) pH [As] (ppm) (mg/g) (PPIn) (mg/g)
As(III) 2.02 9.5 0 50.5 0 50.5
As(V) 1.89 5 149 43.5 163 42.5
Table 10: Arsenic extraction from the ceria surface using redox and
competition reactions
Extractant pH % As(IH) recovered % As(V) recovered
Water 7 0.0 1.7
1 N NaOH 13 0.2 60.5
20% NaOH 14 2.1 51.8
0.25 P043- 8 0.4 15.0
10 g/L C032- 10 2.0 7.7
10% oxalate 2.5 3.0 16.5
30% H202 6 2.0 1.5
H202/NaOH 13 25.2 31.0
0.1 M ascorbate 4 0.0 0.0
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Table 11: Loading and extraction of other adsorbed elements from the ceria
surface (extraction
is shown for each method as the 'percent loaded that is recovered)
Per- Per-
chromate antimony manganate manganate
loading pH 8 2 6 11
loading (mg/g) 20 1 4 0.7
water (% rec) 5.1 <2 2.6 3.4
1 N NaOH (% rec) 83 <2 49.9 17.8
10% oxalic (% rec) 25.8 2.3 22.8 <3
0.5 M P043- (%
rec) 60.7 78.6 45.8
30% H202 (% rec) 2.3
Example 9
Struvite particles comprising NH4MgPO4=6H20 were mixed in CeC13 solutions
having
different molar ratios of CeC13 to NH4MgPO4=6H20 of about 0.8, 1.0, 1.2 and
1.5 CeC13 to
NH4MgPO4.6H20. In each instance, the mass of the struvite was about 0.2g, and
the
concentration of CeC13 was about 0.5 mole/L. Furthermore, controls of about
0.2 grams of
struvite in about 0.1L de-ionized water were prepared. The pH value of each
solution was
adjusted to a pH of about pH 4.3 0.2. Magnetic stir-bars were used to stir
each sample
solution. After stirring for at least about 16 hours, the solids were filtered
from the solution. The
filtered solids were analyzed by x-ray diffraction and the solutions were
analyzed by ICP-MS.
Final solution pH values of the solutions ranged from about pH 4.6 to about pH
8Ø The results
are summarized in Table 12.
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Table 12
Nominal Concentrations Residual Concentrations
Struvit pH Mg P Ce pH Mg P Ce
Sample e Initia
(ppm (ppm (ppm Fina (ppm (ppm (ppm Remova
ID (mg) 1 ) 1 ) 1
A 205 5.0 203 258 935 8.0 140 7.9 <0.1 96.9%
205 5.6 203 259 1171 7.9 170 8.8 <0.1 96.6%
199 5.6 197 251 1360 5.3 170 <0.5 62 >99.8%
202 4.9 200 255 1732 4.7 190 <0.5 270 >99.8%
CONTRO
198 5.6 196 250 0 9.3 19 21 0 N/A
CONTRO
204 5.0 202 257 0 5.1 190 260 0 N/A
CONTRO
200 7.0 198 253 0 7.5 70 100 0 N/A
Example 10
Struvite, NH4MgPO4=6H20, particles were mixed in about 0.1 L solutions
containing
different rare earth chlorides. The rare earth chloride solutions were about
0.15 mol/L solutions
of LaC13, CeCI3, PrC13 and NdC13. The mass of struvite added to each rare
earth chloride
solution was about 0.2 g and the molar ratio of the rare earth chloride to
struvite was about 1Ø
The pH of rare earth chloride solution was adjusted to a pH of about pH 4.3
0.2. Magnetic stir-
bars were used to stir each sample solution. After stirring for at least about
16 hours, the solids
were filtered from the solution. The filtered solids were analyzed by x-ray
diffraction and the
solutions were analyzed by ICP-MS. Final solution pH values ranged from about
pH 4.6 to
about pH 8Ø The results are summarized in Table 13.
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Table 13
Nominal Concentrations Residual Concentrations
Rare
Earth Struvit pH Mg P REE pH Mg P REE
Elemen e Initia (ppm (ppm (ppm Fina (ppm (ppm (ppm Remova
(mg) 1 ) 1 ) 1
La 202 2.3 200 255 1142 2.7 150 <0.5 200 >99.8%
Cc 201 7.0 199 254 1148 5.4 110 <0.5 220 >99.8%
Pr 201 3.41 199 254 1156 3.8 190 <0.5 0.17 >99.8%
Nd 202 2.7 200 255 1188 3.3 180 <0.5 .012 >99.8%
Example 11
Example 11 is a control having about 0.2 g of struvite, NH4MgPO4.6H20,
particles
mixed in about 0.1L of a 0.15 mol/L acidic ferric chloride, FeCl3, solution.
The molar ratio of
ferric chloride to struvite was about 1.0 and the initial pH of the solution
was about pH 2.5. The
initial pH of the control solution was low enough to dissolve the struvite
without the presence of
ferric chloride. A magnetic stir-bar was used to stir the control solution.
After stirring for at
least about 16 hours, the solids were filtered from the control solution. The
filtered solids were
analyzed by x-ray diffraction and the control solution was analyzed by ICP-MS.
Final solution
pH value was about pH 2.3. The results are summarized in Table 14.
Table 14
Nominal Concentrations Residual Concentrations
Metal Struvit pH Mg P REE pH Mg P Metal
Elemen e Initia (ppm (ppm (ppm Fina (ppm (ppm (ppm Remova
(mg) 1 ) 1 ) 1
Fe 200 2.5 198 252 454 2.3 190 22 2.2 91.3%
The Examples 9-11 show that struvite can be more effectively removed with rare
earth-
containing compositions than with other removal materials such as ferric
chloride.
Example 12
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Table 15 summarizes deposit material removal capacities from deinoized and NSF
waters
for cerium dioxide.
Table 15
Deposit Removal Capacity (mg/g)
Material DI NSF
Antimonate 10.91
Arsenite 11.78 13.12
Arsenate 0.86 7.62
Nitrate 0.00
Phosphate 35.57
Sulfate 46.52
Example 13
Experiments were performed to remove metals and metalloids from de-ionized and
NSF
standardized waters (see Table 16) by a cerium-containing composition.
Table 16
Removal Capacity (mg/g)
Contaminant
DI NSF
Antimony 10.91
Arsenic (III) 11.78 13.12
Arsenic (V) 0.86 7.62
Cadmium 10.73 9.75
Chromium
4.35 0.01
(VI)
Copper 9.91 11.65
Lead 15.23 7.97
Mercury _ 12.06 3.33
Uranium 12.20 9.10
Zinc 8.28 10.32
As can be seen from Table 16, a cerium-containing composition is effective in
removing
species comprising the target materials of Table 16.
Example 14
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Experiments were performed to qualitatively determine the ability of a cerium-
containing
additive to remove metals and metalloids from de-ionized and NSF standardized
waters (see
Table 17).
Table 17
Can Be removed
Contaminant
DI NSF
Antimony Yes
Arsenic (III) Yes Yes
Arsenic (V) Yes Yes
Cadmium Yes Yes
76 Chromium (VI) Yes
2 Copper Yes Yes
Lead Yes Yes
Mercury Yes Yes
Uranium Yes Yes
Zinc Yes Yes
As can be seen from Table 16, a cerium-containing composition is effective in
removing
species comprising the target materials of Table 17.
Example 15
Experiments were performed to qualitatively determine the removal of organic,
metal,
metalloids and non-metal contaminants from de-ionized and NSF standardized
waters (see
Tables 18 and 19).
Table 18
Pb in NSF 53 Water Removal Capacities
Average Removal Capacity
Media pH Average % Removal
(mg Pb/g media)
CeOz 6.5 11.65 97.97
Agglomerated
6.5 6.35 54.41
CeOz
CeOz _8.5 12.65 97.96
Agglomerated
8.5 6.85 52.43
CeOz
Table 19
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Removal
Initial Volume Time Mass Final
Media Sample pH [Pb] Treated Tested Media [Pb] Capacity
(ug/L) (L) (Hr) (g) (ug/L) (mg Pb/g
Removal
media)
1 6.5 477 0.50 24 0.0176 9.28 13.29 98.05
Ce02 2 6.5
477 0.50 24 0.0274 10.7 8.51 97.76
3 6.5 477 0.50 24 0.0178 9.04 13.14 98.10
1 6.5 438 0.50 24 0.0194 195 6.26 55.48
Agglomerated
2 6.5 438 0.50 24 0.0178 209 6.43 52.28
Ce02
3 6.5 438 0.50 24 0.0191 195 6.36 55.48
1 8.5 490 0.50 24 0.0216 8.28 11.15 98.31
Ce02 2 8.5 490 0.50 24 0.0174 = 11.9
13.74 97.57
3 8.5 490 0.50 24 0.0184 9.84 13.05 97.99
1 8.5 487 0.50 24 0.0204 215 6.67 55.85
Agglomerated
2 8.5 487 0.50 24 0.0181 242 6.77 50.31
Ce02
3 8.5 487 0.50 24 0.0175 238 7.11 51.13
Ce02 is in the form of a powder and agglomerated Ce02 is agglomerated with a
polymeric binder.
Insoluble forms of lead may be removed from an aqueous media containing one or
both
of soluble and insoluble forms of lead by the rare-earth containing
composition. The insoluble
lead may be in the form of colloidal and/or particulate lead, such as, but not
limited to a lead
oxide, lead hydroxide, and/or lead oxy(hydroxyl). The insoluble lead
composition may be in a
hydrated form having one or more waters of hydration.
The NSF testing water composition in defined in one or more of the following
documents: "NSF/ANSI 42-2007a NSF International Standard/ American National
Standard for
Drinking Water Treatment Units - Drinking Water Treatment Units - Aesthetic
Effects"
Standard Developer - NSF International, Designated as a ANSI Standard, October
22, 2007,
American National Standards; "NSF/ANSI 53-2009e NSF International Standard/
American
National Standard Drinking Water Treatment Units - Health Effects" Standard
Developer - NSF
International, designated as an ANSI Standard, August 28, 2009; and "NSF/ANSI
61-2009 NSF
International Standard/ American National Standard for Drinking Water
Additives - Drinking
Water System Components - Health Effects" Standard Developer NSF
International, designated
as an ANSI Standard, August 26, 2009.
Example 16
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High surface area ("HAS") ceria (Surface area: 130 10 m2/g) having a loading
of about
20 mg was contacted with an analyte having about 0.5 mg/L of the reagent in
question and
qualifying as NSF 53 water. The NSF water components are provided in Table 20
below:
Table 20: NSF 53 Water Components
Reagent Concentration (mg/L)
Sodium Bicarbonate 20
Magnesium Sulfate 30
Calcium Chloride 30
The analyte had a pH of pH 12.25 0.25, a temperature of 20-25 C (or ambient
room
temperature.
The analyte was contacted with the HSF ceria for approximately 24 hours.
The reagents in question were bismuth, chromium, cobalt, manganese, zinc and
zirconium species. Under the above conditions, the primary species were
believed to be in
colloidal form.
The media were prepared by measuring 20 mg of HSA ceria in a plastic weigh
boat and
wetting the HAS ceria media with deionized water for at least 30 minutes.
The analyte was prepared in 2.0 L batches in NSF 53. Lead removal water
without added
lead. 1,000 mg,/L SPEX nitric based standards were obtained and were used to
prepare 0.5 mg/L
influents of the reagents in question. This solution was mixed with a high
shear blender (Ninja
Model: BL500 30) for 30 seconds. The pH adjusted to pH 12.25 0.25 with 3M NaOH
and
mixed for an additional 60 seconds. Previous test with higher concentrations
showed that at a
pH of 12.250.25 particulates were present.
The isotherm was prepared by pouring 500 mL of influent into 4 500 mL bottles.
The
previously wetted media were poured into each 500 mL sample bottle. Bottles
were capped and
sealed with electrical tape. Each bottle was then placed within a rolling
container that could hold
up to 10 bottles. The containers were sealed with duct tape and placed on the
rolling apparatus.
Samples and controls were rolled for 24 hours. After 24 hours, the rolling
containers were
removed from the apparatus and the bottles were retrieved from the containers.
For each metal sample, a 5 mL sample was taken and diluted with the addition
of 3 mL
concentration nitric acid and filtered with a 0.2 m filter. The samples were
acidified to ensure
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CA 2832908 2019-01-02
that all metals were in soluble form. Metal samples were analyzed by
Inductively Coupled
Plasma-Mass Spectrometry (ICP-MS). To confirm the presence of colloidal
metals, samples
were first filtered to remove any particulates then acidified to ensure metals
were in soluble
form. Analysis for these test were all below the detection limit for the metal
analyzed. All
isotherms were prepared and tested in the same manner and were thus readily
comparable.
As shown in Table 21, colloidal bismuth, chromium, manganese, and zinc were
all
removed from NSF 53 water with HSA Ceria. The ability to remove the reagent in
question was
based on at least a 10% removal of the reagent in question from the influent.
Table 21
Initial [M+] Final [M+] Removal
Metal Capacity (mg
(ug/L) (ug,/L) Removal
M+/g media)
Bismuth 409.6 88.53 7.73 78.39
Chromium 318.4 262.93 1.38 17.42
Cobalt 374.4 398.4 -0.59 -6.41
Manganese 417.6 366.4 1.27 12.26
Zinc 603.2 499.73 2.53 17.15
Zirconium 321.6 346.13 -0.62 -7.63
*The Final Cone, Removal Capacity, and % Removal were averages taken from
three samples
This table 22 shows the breakdown of cobalt and zirconium.
Table 22
Initial [M+] Final [M+] Removal
Metal Capacity (mg
(ug/L) (ug/L) Removal
M+/g media)
Cobalt 9A 374.40 369.60 0.12 1.28
Cobalt 9B 374.40 440.00 -1.62 -17.52
Cobalt 9C 374.40 385.60 -0.27 -2.99
Zirconium
12A 321.60 316.80 0.12 1.49
Zirconium
12B 321.60 296.00 0.60 7.96
Zirconium
12C 321.60 425.60 -2.59 -32.34
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Colloidal bismuth, chromium, manganese, and zinc were all removed from NSF 53
water with
HSA ceria. These results give us an understanding that, under ideal
conditions, these reagents
could be removed using HSA ceria.
Example 17
This example compares various test results to draw conclusions on how changes
in,
temperature, surface area, speciation, and concentration affect the loading
capacity of arsenic
onto ceria. The experimental procedure is set forth below:
Material: Ce02: L01-4.6%, SA-140 m2/g;
Ce02: L01- 6.3%, SA-210 m2/g
Loading: 40g
Test Solution Constituents (added to 20 L of DI water):
2244.45 g of NiSO4=6H20
119.37 g of CuSO4=5H20
57.81 H3B03
406.11 NaC1
15.01 FeSO4=7H20
4.79 g of CoSO4=7H20
70 con HCl
Test solution conditions:
pH: 1.63
Density: 1.08 mL/g
Column Influent:
pH: For all columns it ranged from pH 1.1 to 1.2
Density: For all columns it was 1.08 g/mL
Temperature: All columns were run at ambient room temperature ¨ 21 C or 70 C
Flowrate: Flow rates ranged from 1 to 1.8 mL/min, or 2.2%-4.0% Bed Volume
Approximate Amount of Flocculent Used: 22 drops of 1% Nalco 7871
Column Bed Dimensions: For all columns 8.5-9 cm by 2.54 cm ID
Media:
150 g of ACS certified NaCI was added to 1 L volumetric. The salt was then
diluted up to
the 1 L mark using DI water. The salt was then transferred to a 2 L beaker and
heated to a boil.
CA 2832908 2019-01-02
Next, 15 mL of concentrated HCI was added the boiling water while being
stirred using a
magnetic stir bar. Quickly after the HCI addition, 40.00 g of dry Ce02 was
slowly added to the
mixing acidic salt solution. This solution is allowed to stir for 5 minutes.
Next, 22 drops of 1%
Nalco 7871 were added to clarify the solution and prevent classification of
the material when it is
added into the column.
Loading the Column:
The flocculated Ce02 media are transferred into a 2.54 cm by 30 cm glass
column. DI
water is flown through the bed at 12 mL/min to settle the bed until it
completely settled down to
8.5 cm. The DI water on top of the bed was decanted and replaced with the
influent solution
then capped and tightly sealed.
Table 23
As Speciation Temp. Loading at Loading at
Concentration ( C)
Theoretical Theoretical
(mg/L) Rare Earth
Oxide
1000 V 21 43 45
3000 V 21 46 48
1000 III 21 47 49
3000 III 21 50 52
1000 V 21 46 50
3000 V 21 50 54
1000 III 21 46 49
3000 III 21 53 56
1000 V 70 59 61
3000 V 70 67 70
1000 III 70 58 61
3000 III 70 64 67
1000 V 70 68 72
3000 V 70 77 82
1000 III 70 58 62
3000 III 70 74 74
6000 V 70 83 89
6000 V 21 72 78
6000 III 70 77 82
6000 III 21 69 73
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As can be seen from Table 23 and Figure 57, the arsenic species loading
capacity of
cerium (IV) oxide loading is affected by changes in temperature, surface area,
speciation, and
arsenic species concentration.
Example 18
This example determined what colloidal metals can be removed by high surface
area
("HSA") cerium (IV) oxide from NSF 53 water. The test parameters were as
follows:
Parameters:
Material: HSA ceria oxide (Surface area: 130 10 m2/g)
Loading: 20 mg
Analyte Cone: 0.5 mg/L of the reagent in question NSF 53 water
Table 24: NSF 53 Water Components
Reagent Concentration (mg/L)
Sodium Bicarbonate 20
Magnesium Sulfate 30
Calcium Chloride 30
pH: Varies
Temperature: 20-25 C ambient room temperature
Contact Duration: 24 hours
Metals Tested: Bismuth, Chromium, Cobalt, Manganese, Zinc, Zirconium,
Aluminum, and
Copper
Media Preparation:
20 mg of HSA ceria oxide was measured out in a plastic weigh boat. The media
were
wetted with DI water for at least 30 minutes.
Influent Preparation:
Influent was prepared in 2.0 L batches in NSF 53 Lead removal water without
added Lead.
1000 mg/L SPEX nitric based standards were obtained and were used to prepare
0.5 mg/L influents
of the reagents in question. This solution was first mixed with a high shear
blender (Ninja Model:
BL500 30) for 30 seconds, then pH adjusted with 3M NaOH or conc. HC1, the
solution was then
mixed for an additional 30 seconds. Oxidation-Reduction-Potential ("ORP")
values were then
adjusted using solid Sodium Sulfite or 12.5% NaC10 solution (see Table 25).
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Table 25: Test Conditions
Sample Metal Target ORP Actual ORP Actual
Metal Target pH
ID Species (mV) (my) pH
1 Bismuth Bi0OH (S) 12.75-14 -400-400 20 13
**1A Bismuth Bi(S) 1-14 -400 225 1.68
2 Chromium Cr203 (S) >7.5 -400 -100 56 8.54
2A Cobalt Co02 (5) 12 na na 12.12
3 Manganese Mn02(S) 5-14 500 350 11.95
3A Manganese Mn203 (5) 11 - 12 200 - 300
279 11.04
38 Manganese Mn304 (5) 12 0.5 0 - 100 14 12
Zinc Zn(OH)2 (5) 8.5 - 11.5 -500- 600 420 10.28
6 Zirconium Zr02 (S) >8.5 na na 12.06
7 Aluminum A1203(H20)(5) 5.75 - 7.5 -400-
800 275 6.74
8 Copper Cu(OH)2 (5) 8 - 10 100- 700
500 9.50
8a Copper Cu20 (S) 9 - 12 -100- 50 49 9.91
**Correct ORP value was not obtained
Test Procedure:
5 Isotherm Prep Procedure:
Four 500 mL bottles were charged with 500 g influent each. The previously
wetted media
were poured into each 500 mL sample bottle. Bottles were capped and sealed
with electrical tape.
Each bottle was then placed within a rolling container that could hold up to
10 bottles. The
containers were then sealed with duct tape and placed on the rolling
apparatus. Samples were rolled
for 24 hours. After 24 hours, the rolling containers were removed from the
apparatus and the bottles
were retrieved from the containers.
Sample Prep Procedure for Analysis:
For each metal sample, a 5 mL sample was taken and diluted with the addition
of 5 mL
10% Nitric acid and then filtered with a 0.2 i.tm filter. The samples were
acidified to ensure that
all metals were in soluble form. Metal samples were analyzed by Inductively
Coupled Plasma-
Mass Spectromctry (ICP-MS). To confirm the presence of insoluble metals,
samples were first
filtered with a 0.2 km filter to remove any insoluble metals then acidified to
ensure all samples
were the same. All isotherms were prepared and tested in the same manner and
were thus readily
comparable.
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Results:
As shown in Tables 26-27, Cr203 (S), Mn304 (S) A1203(H20)(S), Cu(OH)2 (S), and
Cu20
(S) were all removed from NSF 53 water with HSA Ceria. The ability to remove
the reagent in
question was based on at least a 10% removal of the reagent in question from
the influent.
Table 26
Metal Initial Removal
Sample Final [M+] %
Metal Species [M+] Capacity (mg
ID (ugh) Removal
(ug/L) Mqg media)
1 Bismuth Bi0OH (5)
**1A Bismuth Bi(5)
2 Chromium Cr203 (5) 286.11 61.04 5.54 78.67
2A Cobalt Co02(S) 371.4 395.40 -0.59 -6.46 _
_ _
3 Manganese Mn02 (S) 24.10 59.35 -0.88 -146.23
3A Manganese Mn203 (S) 31.84 114.10 -2.03 -258.35
3B Manganese Mn304 (S) 414.6 , 363.40 1.27 12.35
5 Zinc Zn(OH)2 (5) 27.50 13.42 0.35 51.21
6 Zirconium Zr02 (S) 319.1 343.63 -0.62 -
7.69
7 Aluminum A1203(H20)(5) 349.80 1.72 8.70 99.51
8 Copper Cu(OH)2 (5) 291.96 2.12 7.22 99.27
8a Copper Cu20 (5) 343.10 2.92 8.25 99.15
*The Final Cone, Removal Capacity, and % Removal were averages taken from
three samples
**Correct ORP value was not obtained
Table 27
INSOLUBLE METAL REMOVED
Metal Initial Final Removal
Metal Used Species [Mi] [M-1] Capacity (mg %
Removal
(ug/L) (ug/L) M+/g media)
Cobalt 2AA C002 (S) 371.40 366.60 0.12 1.29
Cobalt 2AB Co02(S) 371.40 437.00 -1.62 -17.66
Cobalt 2AC Co02(S) 371.40 382.60 -0.27 -3.02
Manganese 3A Mn02 (5) 24.102 41 -0.39 -68.04
Manganese 3B Mn02 (5) 24.102 72 -1.19 -197.57
-
Manganese 3C Mn02 (S) 24.102 66 -1.05 -173.09
Manganese 3A4 Mn203 (S) 31.84 69 -0.91 -117.40
-
Manganese 3AB Mn203 (S) 31.84 115 -2.05 -260.80
Manganese 3AC Mn203 (S) 31.84 158 -3.13 -396.86
Zinc 5A Zn(OH)2 (5) 27.5 27 0.00 0.20
Zinc 5B Zn(OH)2 (S) 27.5 -22 1.22 178.84
-
Zinc 5C Zn(OH)2 (5) 27.5 34 -0.17 -25.41
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Zirconium 6A ZrO2 (S) 319.10 314.30 0.12 1.50
Zirconium 68 ZrO2 (S) 319.10 293.50 0.60 8.02
Zirconium 6C ZrO2 (S) 319.10 423.10 -2.59 -32.59
Conclusions:
Colloidal chromium, aluminum, and copper were all removed from NSF 53 water
with
HSA ceria. Some experiments indicated that cobalt, zinc, and zirconium were
also removed.
The ability of HAS ceria to remove manganese was unclear.
Example 19
This example determined whether colloidal metals can be removed by high
surface area
("HSA") cerium (IV) oxide from NSF 53 water. The test parameters were as
follows:
Parameters:
Material: HSA Ceria (Surface area: 130+10 m2/g).
Loading: 20 mg.
Analyte Cone: 0.5 mg/L of the reagent in question NSF 53 water, see Table 34.
Table 34: NSF 53 Water Components
Reagent Concentration (mg/L)
Sodium Bicarbonate 20
Magnesium Sulfate 30
Calcium Chloride 30
pH, ORP: Varies see Table: 28.
Temperature: 20-25 C ambient room temperature.
Contact Duration: 24 hours.
Metals Tested: Bismuth, Chromium, Cobalt, Manganese, Zinc, Zirconium,
Aluminum, and
Copper.
Media Preparation:
20 mg of HSA Ceria was measured out in a plastic weigh boat. The media were
wetted
with DI water for at least 30 minutes.
Influent Preparation:
Influent was prepared in 2.0 L batches in NSF 53 Lead removal water without
added Lead.
1000 mg/L SPEX nitric based standards were obtained and were used to prepare
0.5 mg/L influents
of the reagents in question. This solution was first mixed with a high shear
blender (Ninj a Model:
CA 2832908 2019-01-02
BL500 30) for 30 seconds, then pH adjusted with 3M NaOH or conc. HC1, the
solution was then
mixed for an additional 30 seconds. ORP values were then adjusted using solid
Sodium Sulfite or
12.5% NaCIO solution.
Table: 28
Sample Metal Target Target Actual ORP Actual
Metal
ID Species pH ORP (mV) (mV) pH
1 Bismuth Bi0OH (s) 12.75-14 -400 - 400 20
13.00
**1A Bismuth Bi(s) 1-14 -400 20-225 12.05
2 Chromium Cr2O3 (s) >7.5 -400 -100 56 8.54
2A Cobalt C002(s) 12 na na 12.12
3 Manganese Mn02 (s) 5 - 14 500 350 11.95
3A Manganese Mn203 (s) 11 - 12 200 - 300 279
11.04
3B Manganese Mn304(s) 12 0.5 0 - 100 14 12.05
5 Zinc Zn(OH)2 (s) 8.5 - 11.5 -500 - 600 420
10.28
6 Zirconium ZrO2(s) >8.5 na na 12.06
7 Aluminum A1203(H20)(s) 5.75 - 7.5 -400 - 800 275 6.74
8 Copper Cu(01)2(s) 8 - 10 100 - 700 500
9.50
8a Copper Cu2O (s) 9 - 12 -100 - 50 49 9.91
**ORP value estimated, correct value for Bi(s) never obtained value recorded
corresponds to BiCY
Procedure:
Isotherm Prep Procedure:
Four 500 mL bottles were charged with 500 g influent each. The previously
wetted media
were poured into each 500 mL sample bottle. Bottles were capped and sealed
with electrical tape.
Each bottle was then placed within a rolling container that could hold up to
10 bottles. The
containers were then sealed with duct tape and placed on the rolling
apparatus. Samples were rolled
for 24 hours. After 24 hours, the rolling containers were removed from the
apparatus and the bottles
were retrieved from the containers.
Sample Prep Procedure for Analysis:
For each metal sample, a 5 mL sample was taken and diluted with the addition
of 5 mL
10% Nitric acid and then filtered with a 0.2 p.m filter. The samples were
acidified to ensure that
all metals were in soluble form. Metal samples were analyzed by Inductively
Coupled Plasma-
Mass Spectrometry (ICP-MS). To confirm the presence of insoluble metals,
samples were first
filtered with a 0.2 pm filter to remove any insoluble metals then acidified to
ensure all samples
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were the same. All isotherms were prepared and tested in the same manner and
were thus readily
comparable.
Results
The results are presented in Tables 29-30.
Table: 29
Target Initial Final Removal
Sample Metal %
Metal [M+] [M+] Capacity (mg
ID Species (ug/L) (ug/L) M+/g media)
Removal
1 Bismuth Bi00H (s) 557.17 27.77 13.16
95.02
1A Bismuth BiOt 409.6 88.53 7.73
78.39
2 Chromium Cr203 (s) 286.11 61.04 5.54
78.67
2A Cobalt C002(s) 371.4 395.40 -0.59 -
6.46
3 Manganese Mn02 (s) 493 59.35 10.67 87.96
3A Manganese Mn203 (s) 512.5 114.10 9.79
77.74
3B Manganese Mn3 04 (5) 414.6 363.40 1.27
12.35
5 Zinc Zn(OH)2 (s) 532 13.42 12.85 97.48
6 Zirconium Zr02 (s) 319.1 343.63 -0.62 -
7.69
7 Aluminum A1203(H20)(s) 349.80 1.72 8.70
99.51
8 Copper Cu(OH)2 (s) 291.96 2.12 7.22
99.27
8a Copper Cu2O(S) 343.10 2.92 8.25
99.15
*The Final Conc, Removal Capacity, and % Removal were averages taken from
three samples
Table: 30
INSOLUBLE METAL REMOVED
Target Initial
Final [M+] Removal Capacity
Metal Used Metal [M+] % Removal
Species (ug/L)
(ug/L) (mg M+/g media)
Cobalt 2AA C002(s) 371.40 366.60 0.12 1.29
Cobalt 2AB C002(s) 371.40 437.00 -1.62 -17.66
Cobalt 2AC Co02(s) 371.40 382.60 -0.27 -3.02
Zirconium 6A Zr02 (s) 319.10 314.30 0.12 _ 1.50
_
Zirconium 6B Zr02 (s) 319.10 293.50 0.60 8.02
Zirconium 6C Zr02 (s) 319.10 423.10 -2.59 -32.59
*This table was included due to the negative removal capacities or negative
final concentrations of insoluble Cobalt,
Manganese, Zinc, and Zirconium.
Conclusions
All metals solutions were prepared in NSF 53 Arsenic test water without the
addition of
As. These solutions were all challenged with with HSA cerium oxide (Ce02)
There was definite
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removal of Bi (target species Bi0OH (s), BAY') There was definite removal of
Cr (target species
Cr2O3 (s)), Mn (target species Mn02 (s), Mn203 (s), and Mn3O4 (s)), Zn (target
species Zn(OH)2
(s)), Al (target species A1203(H20)(s)), Cu (target species Cu(OH)2 (s) and
Cu2O (s)), and Zr
(target species ZrO2 (s)), . There was apparent removal of Co (target species
Co02(s)) in trial
2AA. These results give us an understanding that under controlled conditions,
insoluble
compounds of Al, Co, Cr, Cu, Mn, Zn, and Zr could be removed using HSA cerium
oxide
(Ce02).
Figures 58-65 show prior art Pourbaix diagrams for the above materials.
Example 20
This example determined whether selected soluble metals can be removed by HAS
cerium (IV) oxide from NSF 53 water.
Parameters:
Material: HSA Ceria (Surface area: 130 10 m2/g).
Loading: 20 mg.
Analyte Cone: 0.5 mg/L of the reagent in question NSF 53 water, see Table 31.
Table 31: NSF 53 Water Components
Reagent Concentration (mg/L)
Sodium Silicate 95
Sodium Bicarbonate 250
Magnesium Sulfate 130
Sodium Nitrate 12
Calcium Chloride 150
pH, ORP: Varies see Table: 32.
Temperature: 20-25 C ambient room temperature.
Contact Duration: 24 hours.
Metals Tested: Aluminum (A134), Barium (Ba2+), Cadmium (Cd2+), Chromium
(Cr3+), Cobalt
(Co2+), Copper (Cu2+), Iron (Fe2+), Manganese (Mn2+), and Nickel (Ni2+).
Media Preparation:
20 mg of HSA Ceria was measured out in a plastic weigh boat. The media were
wetted
with DI water for at least 30 minutes.
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CA 2832908 2019-01-02
Influent Preparation:
Influent was prepared in 2.0 L batches in NSF 53 Lead removal water without
added
arsenic. 1000 mg,/L SPEX nitric based standards were obtained and used to
prepare 0.5 mg/L
influents of the reagents in question. This solution was mixed using a stir
plate, then pH adjusted
with 3M NaOH or 3M HC1. ORP values were then adjusted using solid Sodium
Sulfite or 12.5%
NaCIO solution.
Table: 32
Sample pH Actual ORP Actual
Metal Species Page Group
ID Range pH
Range ORP
Aluminum Al 3+ 22 13 <4.5 3.26 >0 375
2 Barium Ba2+ 40 2 <11 7.93 any 305
3 Cadmium Cd2+ 60 12 1-8.5 7.29 0-800 320
4 Chromium Cr3+ 78 6 <3 2.23 0-800 400
5 Cobalt Co2+ 74 9 1-8.5 7.07 0-800 370
6 Copper Cu2+ 86 11 <7.5 5.62 >200 385
7 Iron Fe2+
102 8 <7 4.46 0-400 160
8 Manganese Mn2 146 7 <9 7.63 0-
800 225
9 Nickel Ni2+ 170 10 <9 7.84 >-400 245
Procedure:
Isotherm Prep Procedure:
Four 500 mL bottles were charged with 500 g influent each. The previously
wetted media
were poured into each 500 mL sample bottle. Bottles were capped and sealed
with electrical tape.
Each bottle was then placed within a rolling container that could hold up to
10 bottles. The
containers were then sealed with duct tape and placed on the rolling
apparatus. Samples were rolled
for 24 hours. After 24 hours, the rolling containers were removed from the
apparatus and the bottles
were retrieved from the containers.
Sample Preparation Procedure for Analysis:
For each metal sample, a 6 mL sample was taken and diluted with the addition
of 0.667
mL concentration nitric acid and then filtered with a 0.2 gm filter. The
samples were acidified to
ensure that all metals were in soluble form. Metal samples were analyzed by
ICP-MS. All
isotherms were prepared and tested in the same manner and were thus readily
comparable.
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Results:
The results are presented in Tables 32-33.
Table: 33
Initial Final .. Removal
Sample Metal
Metal [M+] [M+] Capacity (mg
ID Species Removal
(ug/L) (ug/L) M+/g media)
1 Aluminum Al3+ 520.6927 517.14
0.09 0.68
2 Barium Ba2+ 536.0268 500.73 -- 0.84 --
6.59
3 Cadmium Cd2+ 487.4688 101.46
9.05 79.19
4 Chromium Cr3+ 559.3613 509.80
1.22 8.86
Cobalt Co2+ 504.0252 398.98 2.53 20.84
6 Copper Cu2+ 464.801 126.75 8.21 72.73
7 Iron Fe2+ 651.8104 544.92 2.59
16.40
8 Manganese Mn2+ 520.5816 203.97
7.33 60.82
9 Nickel Ni2+ 486.8021 427.84 1.44
12.11
*The Final Cone, Removal Capacity, and % Removal were averages taken from
three samples
5
Conclusions:
There was definite removal by HSA ceria of dissolved or water soluble Al3+,
Ba2+, Cd2+,
Cr3+, Co2+, Cu2+, Fe2+, Mn2+, and Ni2+ from NSF 53 water.
Figures 3A-E (aluminum), 6A-E (chromium), 7A-F (manganese), 8A-F (iron), 9A-E
(cobalt), 10A-E (nickel), 11A-E (copper), 24A-C (cadmium), 66A-E (barium), and
67A-E
(radium) are prior art Pourbaix Diagrams for the above metals.
A number of variations and modifications of the disclosure can be used. One of
more
embodiments of the disclosure can used separately and in combination. That is,
any embodiment
alone can be used and all combinations and permutations thereof can be used.
It would be
possible to provide for some features of the disclosure without providing
others.
The present disclosure, in various embodiments, configurations, or aspects,
includes
components, methods, processes, systems and/or apparatus substantially as
depicted and
described herein, including various embodiments, configurations, aspects, sub-
combinations, and
subsets thereof. Those of skill in the art will understand how to make and use
the various
embodiments, configurations, or aspects after understanding the present
disclosure. The present
disclosure, in various embodiments, configurations, and aspects, includes
providing devices and
CA 2832908 2019-01-02
processes in the absence of items not depicted and/or described herein or in
various
embodiments, configurations, or aspects hereof, including in the absence of
such items as may
have been used in previous devices or processes, e.g., for improving
performance, achieving ease
and\or reducing cost of implementation.
The foregoing discussion has been presented for purposes of illustration and
description.
The foregoing is not intended to limit the disclosure to the form or forms
disclosed herein. In the
foregoing Detailed Description for example, various features of the disclosure
are grouped
together in one or more embodiments, configurations, or aspects for the
purpose of streamlining
the disclosure. The features of the embodiments, configurations, or aspects of
the disclosure
may be combined in alternate embodiments, configurations, or aspects other
than those discussed
above. This method of disclosure is not to be interpreted as reflecting an
intention that any
claim and/or combination of claims require more features than are expressly
recited in each
claim. Rather, as the following claims reflect, inventive aspects lie in less
than all features of a
single foregoing disclosed embodiment, configuration, or aspect. Thus, the
following claims are
hereby incorporated into this Detailed Description, with each claim standing
on its own as a
separate preferred embodiment.
Moreover, though the description of the disclosure has included descriptions
of one or
more embodiments, configurations, or aspects and certain variations and
modifications, other
variations, combinations, and modifications are within the scope of the
disclosure, e.g., as may
be within the skill and knowledge of those in the art, after understanding the
present disclosure.
It is intended to obtain rights which include alternative embodiments,
configurations, or aspects
to the extent permitted, including alternate, interchangeable and/or
equivalent structures,
functions, ranges or steps to those claimed, whether or not such alternate,
interchangeable and/or
equivalent structures, functions, ranges or steps are disclosed herein, and
without intending to
publicly dedicate any patentable subject matter.
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CA 2832908 2019-01-02
