Note: Descriptions are shown in the official language in which they were submitted.
~Z6~79~
NOVEL COLLECTOR CC)M POS I T I ON
FOR FROTH FLOTATION
:`
This invention concerns a novel collector
composition useful for the recovery of metal-containing
sulfide minerals and sulfidized metal-containing oxide
' minerals from ores by froth flotation.
Flotation is a process of treating a mixture
of finely di~ided minexal solids, e.g., a pulverulent
~ ore, suspended in a liquid whereby a portion of such
; solids is separated from other finely divided solids,
e.g., clays and other like materials present in the
ore, by in-troducing a gas ~or providing a gas ln situ)
in the liguid to produce a frothy mass containing
certain of the solids on the top of the liquid, and
leaving suspended (unfrothed) other so~id components of
the ore. Flotation is based on the principle that
introducing a gas into a liquid containing solid par-
ticles of different materials suspended therein causes
adherence of some gas to certain suspended solids and
not to others and makes the particles having the gas
thus a &ered thereto lighter than the liquid. Accord-
ingly, these particles rise to the top of the li~uidto form a froth.
34, 276-F -1-
.
,
~ -2-
~6797~1
Various flotation agents have been admixed
with the suspension to improve the frothing process.
Such added agents are classed according to the function
to be performed: collectors, for sulfide minerals
including xanthates, thionocarbamates and the like;
; frothers which impart the property of forming a stable
froth, e.g., natural oils such as pine oil and euca-
lyptus oil; modifiers such as activators to induce
flotation in the presence of a collector, e.g., copper
sulfate; depressants, e.g., sodium cyanide, which tend
to prevent a collector from functioning as such on a
mineral which it is desired to retain in th~ liquid,
and thereby discourage a substance from being carried
up and forming a part of the froth; pH regulators to
produce optimum metallurgical results, e.g., lime, soda
ash and the like.
It is of importance to bear in mind that
additives of the hereinbefore described types are
selected for use according to the nature of the ore,
~; 20 the mineral(s) sought to be recovered, and the other
additaments which are to be used in combination there-
with.
An understanding of the phenomena which makes
flotation a particularly valuable industrial operation
is not essential to the practice of the present inven-
tion. The phenomena appear, however, to be largely
associated with selective affinity of the surface of
particulated solids, suspended in a liquid containing
entrapped gas, for the li~uid on the one hand, the gas
on the other.
, :
34,276~F -2
. .
~ -3-
~26~97!~
The flotation principle is applied in a
number of mineral separation processes among which is
the selective separation of such metal sulfide minerals
as those containing copper, zinc, lead, nickel, molyb-
denum, and other metals from iron-containing sulfide
minerals such as pyrite and pyrrhotite.
Among collectors commonly used for the recov-
ery of metal-containing sulfide minerals or sulfidized
; metal-containing oxide minerals are xanthates, dithio-
phosphates, and thionocarbamates. These volatile
sulfur compounds are often released to the atmosphere
through smokestacks, or are removed from such smoke-
stacks by expensive and elaborate scrubbing eguipment.
Many nonferrous metal-containing sulide minerals or
metal-containig oxide minerals are found naturally in
ores which also consist of iron-containing sulfide
minerals. When the iron-containing sulfide minerals
are recovered in flotation processes along with the
nonferrous metal~containing sulfide minerals and sul-
fidized metal-containing oxide minerals, there is
excess sulfur present which is released in the smelting
processes resulting in an undesirably high amount of
sulfur present during the smelting operations. What is
needed is a collector composition useful for selectively
recovering the nonferrous metal-containing sulfide
minerals and sulfidized metal-containing oxide minerals,
without recovering the iron-containing sulfide minerals.
::
Of the commercial collectors, the xanthates,
thionocarbamates, and dithiophosphates do not selec-
tively recover nonferro~s metal-containing sulide
minerals in the presence of iron-containing sulfide
minerals. On the contrary, such collectors collect and
recover all metal-containing sulfide minerals.
34,276-F -3-
-4-
~2~7979
What is needed is a flotation collector
composition which will selectively recover the non-
ferrous metal-containing sulfide minerals or sulfidized
metal-containing oxide minerals in the presence of
~ 5 ferrous sulides.
This invention concerns a novel composition
which is useful as a collector for the recovery of
nonferrous metal-containig sulfide minerals and sulfid-
ized metal-containing oxide minerals from ores in a
froth flotation process. The novel composition com-
prises:
(a) a hydrocarbon con-taining one or more
monosulfide units, wherein the carbon atoms to which
the sulfur atom(s) are bound are aliphatic or cycloali-
phatic carbon atoms, and the total carbon content ofthe hydrocarbon portion is such that the hydrocarbon
has sufficient hydrophobic character to cause the
metal-containing sulfide mineral or sulfidized metal-
-containing oxide mineral particles to be driven to an
air/bubble interface; and
(b) an alkyl thiocarbonate, a thionocarba-
mate, a thiophosphate, or mixtures thereof.
`:
The novel collectors of this invention result
in surprisingly high recovery of nonferrous metal-con-
taining sulfide minerals or sulfidized metal-containing
oxide minerals and good selectivity toward such non-
ferrous metal-containing sulfide minerals and sulfi-
; dized metal-containing oxide minerals when such metal-
;~ containing sulfide minerals or sulfidized metal-con-
taining oxide minerals are found in the presence of
~- iron-containing sulfide minerals. These collectors
demonstrate good recovery and good kinetics.
34,276-F -4-
lZ~;797~
One component of the novel collector compo-
sition of this invention is a hydrocarbon which con-
tains one or more monosulfide units wherein the sulfur
atoms of the sulfide units are bound to non-aromatic
carbon atoms, i.e., aliphatic or cycloaliphatic carbon
atoms. Monosulfide unit refers herein to a unit wherein
a sulfur atom is bound to two carbon ato~s of a hydro-
carbon moiety only. Such hydrocarbon compounds con-
taining one or more monosulfide units, as used herein,
include such compounds which are substituted with
hydroxy, cyano, halo, ether, hydrocarbyloxy and hydro~
carbyl thioether moieties. Non-aromatic carbon atom
refers herein to a carbon atom which is not part of an
aromatic ring.
Preferred hydrocarbons containing monosulfide
units include those corresponding to the formula
; Rl_s-R~ I
wherein
R1 and R2 are independently a hydrocarbyl
radical or a hydrocarbyl radical substituted with
one or more hydroxy, cyano, halo, ether, hydro-
carbyloxy or hydrocarbyl thioether moieties;
wherein
R1 and R2 may combine to form a heterocyclic
ring structure with S; with the proviso that S is bound
to an aliphatic or cycloaliphatic carbon atom; with the
further proviso that the total carbon content of the
hydrocarbon sulfide be such that it has sufficient
.
34,276-F -5-
~ -6-
~67~79
hydrophobic character to cause the metal~containing
sulfide mineral or sulfidized metal-containing oxide
mineral particles to be driven to an air/bubble inter-
face.
Preferably, Rl and R2 are independently an
aliphatic, cycloaliphatic or aralkyl moiety, unsubsti-
tuted or substituted with one or more hydroxy, cyano,
halo, oR3, or SR3 moieties, wherein R3 is a hydrocarbyl
radical, wherein R1 and R2 may combine to form a hetero-
cyclic ring with S. Rl and R2 are more preferably an
aliphatic or cycloaliphatic moiety, unsubstituted or
substituted with one or more hydroxy, cyano, halo, OR ,
or SR3 moieties; wherein Rl and R2 may combine to form
a heterocyclic ring with S. In a more preferred embodi-
ment, R1 and R2 do not combine to form a heterocyclicring with sulfur and Rl and R2 are alkyl, alkenyl,
alkynyl, cycloalkyl or cycloakenyl, unsubstituted or
substituted with one or more hydroxy, halo, cyano, oR3
SR3 moieties, wherein R3 is aliphatic or cycloaliphatic.
In a most preferred embodiment, Rl is methyl or ethyl.
R is a C6_11 alkyl or alkenyl group. In the most
preferred embodiment, R and R are not the same hydro-
carbon moiety, that is, the monosulfide is as~mmetrical.
R3 is preferably aliphatic or cycloaliphatic. R3 is
more preferably alkyl, alkenyl, cycloalkyl or cyclo
,~ alkenyl.
` The total carbon content of the hydrocarbon
portio~ of the hydrocarbon monosulfide must be such
that the hydrocarbon sulfide has sufficient hydrophobic
character to cause the metal-containing sulfide mineral
or sulfidized metal-containing oxide mineral particles
to be driven to the air/bubble interface. Preferably,
34,276-F -6-
lZ167~379
the total carbon content of the hydrocarbon monosulfide is such
that the minimum carbon number is 4, more preferably 6, and most
preferably 8. The maximum carbon content is preferably 20,
more preferably 16, and most preferably 12.
Examples of cyclic compounds which are hydrocarbon
sulfides of this invention include the following structures.
(R )2~~C~(R )2 and R S
Ia Ib
wherein R is independently hydrogen, aryl, alkaryl, aralkyl,
alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, hydroxy,
cyano, halo, OR , SR , wherein the aryl, alkaryl, aralkyl, alkyl,
alkenyl, alkynyl, cycloalkyl, cycloalkenyl may optionally be
substituted with a hydroxy, cyano, halo, oR3 or SR3 moiety, and
:~ the like; and R is a straight- or branched-alkylene, -alkenylene,
or -alkynylene, unsubstituted or substituted with a ~ydroxy,
cyano, halo, OR or SR moiety.
In another preferred embodiment of this invention, the
hydrocarbon sulfides useful in this invention correspond to the
formula
20(R )3_nC(H)n-s-c(H)n~R )3-n Ic
or
R )2-C - CH2 Id
S
wherein
R is defined as above;
: R is independently hydrocarbyl, or hydrocarbyl
substi*uted with a hydroxy, cyano, halo,
--7--
~ . h
--8--
~Z67~7~
ether, hydrocarbyloxy or hydrocarbyl thioe-ther
moiety; wherein two R6 moieties may combine to
form a cyclic ring or heterocycl.ic ring with the
sulfur atom;
n is an integer of 0, 1, 2 or 3; with the
proviso that the total carbon content of the
hydrocaxbon portion of the collector is such that
the collector has sufficient hydrophobic character
to cause the metal-containing sulfide mineral or
sulfidized metal-containing oxide mineral par-
ticles to be driven to the air/bubble interface.
Preferably, R6 is aliphatic, cycloaliphatic,
aryl, alkaryl or aralkyl, unsubstituted or substituted
with a cyano, hydroxy, halo, oR3 or SR3 moiety, wherein
R3 is as hereinbefore defined. More preferahly, R6 is
an aliphatic or cycloaliphatic moiety, unsubstituted or
substituted with a hydroxy, cyano, aliphatic ether,
cycloaliphatic ether, aliphàtic thioether or cycloali-
phatic thioether moiety. Even more preferably, R6 is
~- 20 an alkyl, alkenyl, cycloalkyl or cycloalkenyl moiety
Most preferably, one -C(H)n(R6)3 n is a methyl or ethyl
moiety, and the other is a C6 11 alkyl or alkenyl
moiety. Preferably, n is 1, 2 or 3, and more prefer-
ably 2 or 3.
Examples of hydrocarbon sulfides within the
scope of this invention include methylbutyl sulfide,
methylpentyl sulfide, me-thylhexyl sulfide, methylheptyl
sulfide, methyloctyl sulfide, methylnonyl sulfide,
methyldecyl sulfide, methylundecyl sulfide, methyl-
dodecyl sulfide, methylcyclopentyl sulfide, me-thyl-
cyclohexyl sulfide, methylcycloheptyl sulfide, methyl-
cyclooctyl sulfide, ethylbutyl sulfide, ethylpentyl
34,~76-F -8-
1~6~7~7g
sulfide, ethylhexyl sul~ide, ethylheptyl sulfide,
ethyloctyl sulfide, ethylnonyl sulfide, ethyldecyl
sulfide, ethylundecyl sulfide, ethyldodecyl sulfide,
ethylcyclopentyl sulfide, ethylcyclohexyl sulfide,
ethylcycloheptyl sulfide, ethylcyclooctyl sulfide,
propylbutyl sulfide, propylpentyl sulfide, propylhexyl
sulfide, propylheptyl sulfide, propyloctyl sulfide,
propylnonyl sulfide, propyldecyl sulfide, propylundecyl
sulfide, propyldodecyl sulfide, propylcyclopentyl
sulfide, propylcyclohexyl sulfide, propylcycloheptyl
sulfide, propylcyclooctyl sulfide, dibutyl sulfide,
butylpentyl sulfide, butylhexyl sulfide, butylheptyl
sulfide, butyloctyl sulfide, butylnonyl sulfide, butyl-
decyl sulfide, butylundecyl sulfide, butyldodecyl
sulfide, butylcyclopentyl sulfide, butylcyclohexyl
sulfide, butylcycloheptyl sulfide, butylcyclooctyl
sulfide, dipentyl sulfide, pentylhexyl sulfide, pentyl-
heptyl sulfide, pentyloctyl sulfide, pentylnonyl sul-
fide, pentyldecyl sulfide, pentylundecyl sulfide,
pentyldodecyl suLfide, pentylcyclopentyl sulfide,
: pentylcyclohexyl sulfide, pentylcycloheptyl sulfide,
pentylcyclooctyl sulfide, dihexyl sulfide, hexylheptyl
sulfide, he~yloctyl sulfide, hexylnonyl sulfide, hexyl-
decyl sulfide, hexylundecyl sulfide, hexyldodecyl
sulfide, hexylcyclopentyl sulfide, hexylcyclohexyl
; sulfide, hexylcycloheptyl sulfide, hexylcyclooctyl
sulfide, diheptyl sulfide, heptyloctyl sulfide,
, heptylnonyl sulfide, heptyldecyl sulfide, heptylundecyl
sulfide, heptyldodecyl sulfide, heptylcyclopentyl
sulfide, heptylcyclohexyl sulfide, heptylcycloheptyl
sulfide, heptylcyclooctyl sulfide, dioctyl sulfide,
octylnonyl sulfide, octyldecyl sulfide, octylundecyl
34,276-F -9-
` --10--
31;Z67~
sulfide, octyldodecyl sulfide, octylcyclopentyl sul-
fide, octylcyclohexyl sulfide, octylcycloheptyl sul-
fide, octylcyclooctyl sulfide, octylcyclodecyl sulfide,
dinonyl sulfide, nonyldecyl sulfide, nonylundecyl
sulfide, nonyldodecyl sulfide, nonylcyclopentyl 5ul-
fide, nonylcyclohexyl sulfide, nonylcycloheptyl sul-
fide, nonylcyclooctyl sulfide, didecyl sulfide, decyl-
undecyl sulfide, decyldodecyl sulfide, decylcyclopentyl
sulfide, decylcyclohexyl sulfide, decylcycloheptyl
sulfide, and decylcyclooctyl sulfide. More preferred
sulfides include methylhexyl sulfide, methylheptyl
sulfide, methyloctyl sulfide, methylnonyl sulfide,
methyldecyl sulfide, ethylhexyl sulfide, ethylheptyl
sulfide, ethyloctyl sulfide, ethylnonyl sulfide, ethyl-
decyl sulfide, dibutyl sulfide, dipentyl sulfide,dihexyl sulfide, diheptyl sulide, and dioctyl sulfide.
The second component of the novel collector
composition of thi~ invention is an alkyl thiocarbon-
ate, a thionocarbamate, a thiophosphate, or mixtures
thereof. Alkyl thiocarbonates refer herein to those
compounds which contain a thiocarbonate moiety and at
least one alkyl moiety wherein the alkyl moiety has
sufficient hydrophobic character 50 as to cause a
metal-containing sulfide mineral or sulfidized metal-
containing oxide mineral particles associated therewithto be driven to an air/bubble interface. Preferred
alkyl thiocarbonates correspond to the formula
' X
R7-X-C-S-M+ II
34,276-F -lO-
~LZ~7~7~ -
wherein
R7 is a C1 20 alkyl group;
X is independently in each occurrence
S or O;
M is an alkali metal cation.
Preferred alkyl thiocarbonates include
alkyl monothiocarbonates, alkyl dithiocarbonates,
or alkyl trithiocarbonates.
Preferred alkyl monothiocarbonates cor-
respond to the formula
o
R7-o-C-S M IIa
wherein R7 and M are as defined hereinbefore.
Examples of preferred alkyl monothio~
carbonates include sodium ethyl monothiocarbonate,
sodium isopropyl monothiocarbonate, sodium iso-
butyl monothiocarbonate, ~odium amyl monothiocar-
bonate, potassium ethyl monothiocarbonate, potas-
sium isopropyl monothiocarbonate, potassium iso-
butyl monothiocarbonate, and potassium amyl mono-
thiocarbonate.
Alkyl dithiocarbonates are commonly
referred -to as xanthates. Preferred alkyl di-
thiocarbonates correspond to the formula
.
,::
, ~
: :~
34,276-F -11-
12679~9
R7-o-c-S M Ila
wherein R7 and M are as hereinbefore defined.
Preferr~d alkyl dithiocarbonates
include potassium ethyl dithiocarbonate, sodium
ethyl dithiocarbonate, potassium amyl dithiocar-
bonate, sodium amyl dithiocarbonate, potassium
isopropyl dithiocarbonate, sodium isopropyl di-
thiocarbonate, sodium sec-butyl dithiocarbonate,
potassium sec-butyl dithiocarbonate, sodium iso-
butyl dithiocarbona-te, potassi~n isobutyl dithio-
carbonate, and the like.
Preferred alkyl trithiocarbonates cor-
respond to the formula
~ ~ S
R7-S-C-S M IIc
.~
wherein R7 and M are as hereinbefore defined.
Examples of alkyl trithiocarbonates
include sodium isobutyl trithiocarbonate and
potassium isobutyl trithiocarbonate.
Preferred thionocarbamates correspond
to the formula
:
34,276-F -12-
~ -13-
~Z~7~
~R )a-N-C-Y III
(H)b
wherein
R8 is independently in each occurrence
a Cl 10 alkyl group; 9
Y is -S M or -OR9, wherein R is a
:~ 10C1_10 alk~l group;
a is the integer 1 or 2; and
b is the integer 0 or 1, wherein a+b
must equal 2.
Preferred thionocarbamates include
dialkyl dithiocarbamates and alkyl thionocarba-
mates. Preferred dialkyl dithiocarbamates cor-
respond to the formula
.,
R S
~-C-S M+ IIIa
8/
wherein M is as hereinbe~ore defined; and R8 is
independently a C1 10 alkyl group.
Examples of preferred dialkyl dithio-
carbamates include methyl butyl dithiocarbamate,
methyl isobutyl dithiocarbamate, methyl sec-butyl
dithiocarbamate, methyl propyl dithiocarbamate,
methyl isopropyl dithiocarbamate, ethyl butyl
34,276-F ~13-
,~.,
,
-14-
i7979
dithiocarbamate, ethyl isobutyl dithiocarbamate,
ethyl sec~butyl dlthiocarbamate, ethyl propyl
dithiocarbamate, and ethyl isopropyl dithiocar-
bamate.
Preferred alkyl thionocarbamates cor-
respond to the formula
R8-NH-C-OR9 IIIb
wherein R8 is as hereinbefore defined and R9 is
a C1 10 alkyl group.
E~amples of preferred alkyl thionocar-
bamates include N-methyl butyl thionocarbamate,
N-methyl isobutyl thionocarbamate, N-methyl sec-
-butyl thionocarbamate, N-methyl propyl thiono-
` carbamate, N-methyl isopropyl thionocarbamate,
,~ ~ N-ethyl butyl thionocarbamate, N-ethyl isobutyl
thionocarbamate, N-ethyl sec-butyl thionocarba-
mate, N-ethyl propyl thionocarbamate, and N-ethyl
isopropyl thionocarbamate. More preferred thiono-
carbamates include N-ethyl isopropyl thionocarba-
mate and N-ethyl isobutyl thionocarbamate.
.
; Preferred thiophosphates generally cor-
respond to the formula
RlOO S
\ + IV
,~ x-rq
Rl O o~
34,276-F -14-
. -15-
~67~7~
wherein
R10 is independently hydrogen,
a Cl_10 alkyl group or an aryl group;
: X is oxygen or sulfur; and
M is an alkali metal cation.
Preferred thiophosphates include monoalkyl
dithiophosphate, dialkyl dithiophosphate, diaryl dithio-
phosphate, and dialkyl monothiophosphate. Preferred
monoalkyl dithiophosphates corresponcl to the formula
R10O S
P-S M+ IVa
HO~
wherein R10 and M are as hereinbefore defined.
Examples of preferred monoalkyl dithio-
~ phosphates include ethyl dithiophosphate, propyl
;~ ~ dithiophosphate, isopropyl dithiophosphate, butyl
` dithiophosphate, sec-butyl dithiophosphate, and
isobutyl dithiophosphate.
Preferred dialkyl and diaryl dithiophos-
phates correspond to the formula
R10O S
S M+ IVb
R1OO
~:: :
34, 2i6 F -15-
- -16
~ iL267979
wherein R10 and M are as hereinbefore defined.
Examples of dialkyl and dlaryl dithiophos-
phates include sodium die-thyl dithiophosphate, sodium
di-sec-butyl dithiophosphate, sodium diisobutyl dithio-
phosphate, sodium diisoamyl dithiophosphate, and sodiumdicresyl dithiophosphate.
Preferred dialkyl monothiophosphates cor-
respond to the formula
R10O S
\P-O M IVc
RlOo/
wherein R10 and M are as hereinbefore defined.
Preferred monothiophosphates include sodium
diethyl monothiophosphate, sodium di-sec-butyl mono-
thiophosphate, sodium diisobutyl monothiophosphate, and
sodium diisoamyl monothiophosphate.
R is8preferably C2_16 alkyl, more preferably
C3 12 alkyl. R is preferably Cl 4 alkyl and most
preferably Cl 3 alkyl. R9 is preferably C2 10 alkyl,
more preferably C2 6 alkyl and most preferably C3 4
alkyl. R is preferably C2 8 alkyl or cresyl.
Preferably, the composition of this invention
comprises: (a) the hydrocarbon sulfide of formula I to
(b) the alkyl thiocarbonate of formula II, thionocar-
bamate of formula III, thiophosphate of formula IV, or
mixture thereof, in a ratio such that the composition
, 34,276-F -16-
~ -17-
~;26~79
is an effective collector for metal-containing sulfide
minerals and sulfidized metal-containing oxide minerals
in a froth flotation process.
- The composition of this invention preferably
comprises: (a) between a~out 10 and about 90 percent by
weight of hydrocarbon sulfide of formula I; and (b)
between about lO and about 90 percent by weight of an
alkyl thiocarbonate of formula II, thionocarbamate of
formula IIIj thiophosphate of formula IV, or mixtures
thereof.
The composition of this invention more pre-
ferably comprises: (a) between about 20 and about 80
percent by weight of a hydrocarbon sulfide of formula
I; and (b) between about 20 and about 80 percent by
weight of an alkyl thiocarbonate of formula II, thio-
nocarbamate of formula III, thiophosphate of formula IV
or mixtures thereof.
The composition of this invention even more
preferably comprises: (a) between about 30 and 70
percent by weight of a hydrocarbon sulfide of formula
I; and (b) between about 30 and 7Q percent by weight of
an alkyl thiocarbonate of formula II, thionocarbamate
of formula III, thiophosphate of formula IV or mixtures
thereof. In its most preferred embodiment, the ratio
of hydrocarbon sulfide of formula I to alkyl thiocar-
bonate of formula II, thionocarbamate of formula III,
thiophosphate of formula IV or mixtures thereof is such
that the recovery of metal~containing sulfide minerals
or sulfidized metal-containing oxide minerals in a froth
flotation process is higher than either component alone
could recover at the same weight dosage. More preferably,
34,276-F -17-
~2~;~9 ~
the dosage at which ~he collector is used, is that
dosage at which the component (b) of formula II, III,
or IV of the composition when used alone gives a higher
recovery than the hydrocarbon sulfide of formula I
gives at such level.
The novel collector composition of this
invention gives higher recoveries, often with better
metal grade(s), than can be achieved with the use of
either collector component alone. Grade is defined
as the fractional amount of a desired metal contained
in the materil collected in the froth.
` Hydrocarbon means herein an organic
compound containing carbon and hydrogen atoms. The
term hydrocarbon includes the following organic com-
pounds: alkanes, alkenes, alkynes, cycloalkanes,cycloalkenes, cycloalkynes, aromatics, aliphatic
and cycloaliphatic aralkanes and alkyl-substituted
aromatics.
Aliphatic refers herein to s-traight-
and branched-chain, and saturated and unsaturated,
hydrocarbon compounds, that is, alkanes, alkenes
or alkynes. Cycloaliphatic reers herein to satu-
rated and unsaturated cyclic hydrocarbons, that
is, cycloalkenes and cycloalkanes.
Cycloalkane refers to an alkane contain-
ing one, two, three or more cyclic rings. Cycloal-
kene refers to mono-, di- and polycyclic groups
containing one or more double bonds.
34,276-F -18-
, ~ --19--
~7~
~ ydrocarbyl means herein an organic radical
containing carbon and hydrogen atoms. The term hydro-
carbyl includes the following organic radicals: alkyl,
alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl,
aliphatic and cycloaliphatic aralkyl and alkaryl. The
term aryl refers herein to biaryl, biphenylyl, phenyl,
naphthyl, phenanthrenyl, anthracenyl and two aryl
groups bridged by an alkylene group. Alkaryl refers
herein to an alkyl-, alkenyl- or alkynyl substituted
aryl substituent, wherein aryl is as deflned hereinbe-
fore. Aralkyl means herein an alkyl group, wherein
aryl is as defined hereinbefore.
Cl 20 alkyl includes straight- and branched-
~chain methyl, ethyl, propyl, butyl, pentyl, hexyl,
heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl,
tetradecyl, pentadecyl, hexadecyl, hep-tadecyl, octadecyl,
nonadecyl and eicosyl groups.
Halo means herein a chloro, bromo or iodo
group.
The novel collector compositions of this
; invention are useful for the recovery by froth flota-
tion o~ metal-containing sulfide minerals and sulfi-
dized metal-containing oxide minerals from ores. An ore
refers herein to material as it is taken out of the
ground and includes the desired metal-containing
minerals in admixture with the gangue. Gangue refers
herein to that portion of the material which is of no
value and needs to be separated from the desired metal-
-containing minerals.
34,276-F -19-
- -20--
~L26797~
In a preferred embodiment, metal-containing
sulfide minerals are recovexed. In a more preferred
embodiment of this invention sulfide minerals contain-
ing copper, nickel, lead, zinc or molybdenum are recov-
ered. In an even more preferred embodiment, sulfideminerals containing copper a.re recovered. Also pre-
ferred metal sulfide-containing minerals are those
which have high natural hydrophobicity in the unoxi-
dized state. The term "hydrophobicity in the unoxi-
dized state" applies to a freshly ground mineral ora mineral having a fresh surface which demonstrates
a tendency to float without collector addition.
Ores for which these compositions are useful
include sulfide mineral ores containing copper, zinc,
molybde~um, cobalt, nickel, lead, arsenic, silver,
chromium, gold, platinum, uranium, and mixtures thereof.
Examples o metal-containing sulfide minerals which
may be concentra-ted by froth 10tation using the pro-
cess of this invention include copper-bearing minerals
such as, for example, covellite (CuS), chalcocite
(Cu2S), chalcopyrite (CuFeS2), valleriite (Cu2Fe4S7 or
Cu3Fe4S7), tetrahedrite (Cu3SbS2), bornite (Cu5FeS4),
,! cubanite (Cu2SFe4S5), enargite [Cu3(As1Sb)S4], ten-
nantite (Cu12As4S13), brochantite [Cu4(OH)6S04], ant-
lerite [Cu3S04(0H~4], famatinite ~Cu3(SbAs)S4~, and
bournonite (PbCUSbS3); lead-bearing minerals such as,
for example, galena (PbS); antimony-bearing minerals
such as, for example, stibnite ~Sb2S3); zinc-bearing
minerals such as, for example, sphalerite (ZnS);
silver-bearing minerals such as, for example, steph-
anite (Ag5SbS4), and argentite (Ag2S); chromium-bearing
minerals such as, for example, daubreelite (FeSCrS3);
34,276-F -20-
~2~7g7~
nickel-bearing minerals such as, for example, pent-
landite [(FeNi)gS8]; molybdenum-bearing minerals such
as, for example, moly~denite (MoS2); and platinum- and
palladium beariny minerals such as, for example, cooper-
ite [Pt(AsS)2]. Preferred metal-containing sulfide
minerals include molybdenite (MoS2), chalopyrite (CuFeS2),
galena (Pbs), sphalerite (ZnS), bornite (Cu5FeS4~ and
pentlandite [(FeNi)gS8].
Sulfidized metal-containing oxide minerals
are minerals which are treated with a sulfidization
chemical, so as to give such minerals sulfide mineral
characteristics, so the minerals can be recovered in
froth flotation using collectors which recover sulfide
minerals. Sulfidization results in oxide minerals
having sulfide characteristics. Oxide minerals are
sulfidized by contact with compounds which react with
the minerals to form a sulfur bond or affinity. Such
methods are well-known in the art. Such compounds
include sodium hydrosulfide, sulfuric acid and related
sulfur containing salts such as sodium sulfide.
Sulfidized oxide minerals for which this
process is useful include oxide minerals containing
copper, aluminum, iron, titanium, tungsten, molybdenum,
magnesium, chromium, nickel, manganese, tin, uranium,
and mixtures thereof. Examples of metal-containing
; oxide minerals which may be concentrated by froth
flotation using the process of this invention include
copper-bearing minerals, such as cuprite (Cu2O~, tenor-
ike (CuO), malachite [(Cu2OH)2CO3], azurite ~Cu3(OH)2-
30 (CO3)2], atacamite [Cu2Cl(OH)3], chrysocolla ~cusio3);
aluminum-bearing minerals, such as corundum; zinc-con-
taining minerals, such as zincite (ZnO), and smithsoni-te
34,276-F -21-
-22-
~Z~7979
(ZnC03); tungsten-bearing minerals such as, for example,
wolframite [~Fe,Mn)W04]; nickel-bearing minerals such
as, for example, bunsenite (NiQ); molybdenum-bearing
minerals such as, for example, wulfenite (PbMoO4) and
powellite (CaMoO4); iron-containing minerals, such as
hematite and magnetite; chromium~containing minerals,
such as chromite (FeOCr203); iron- and titanium-con-
taining minerals, such as ilmenite; magnesium- and
aluminum-containing minerals, such as spinel; iron-
chromium-containing minerals, such as chromite; tita-
nium-containing minerals, such as rutile; manganese-
containing minerals, such as pyrolusite; tin-containing
minerals, such as cassiterite; and uranium-containing
minerals, such as uraninite; and uranium-bearing miner-
als such as, or example, pitchblende [U205(U308)~ and
gummite (U03nH20)-
The collectors of this invention can be used
in any concentration which gives the desired recovery
of the desired minerals. In particular, the concen-
tration used is dependent upon the particular mineralsto be recovered, the grade of the ore to be subjected
to the froth flotation process, the desired quality of
the mineral to be recovered, and the particular mineral
which is being recovered. Preferably, the collectors
of this invention are used in concentrations of 0.001
; to 1.0 kg per metric ton of ore, more preferably between
0.010 and 0.2 kg of collector per metric ton of ore to
be subjected to froth flotation.
Frothers are preferably used in the froth
flotation process of this invention. Any frother
well-known in the art, wh.ich results in the recovery of
the desired mineral is suitable.
34,276-F -22-
`` -23-
~Z6~9~9
Frothers useful in this invention include any
frothers known in the art which give the recovery of
the desired mineral. Examples of such frothers include
C5 8 alcohols, pine oils, cresols, C1 4 alkyl ethers of
polypropylene glycols, dihydroxylates of pol~propylene
glycols, glycols, fatty acids, soaps, alkylaryl sulfo-
nates, and the like. Furthermore, blends of such
frothers may also be used. All frothers which are
suitable for beneficiation of ores by froth flotation
can be used in this invention.
Further, in the process of this invention it
is contemplated that collectors of this invention can
be used in mixtures with other collectors well-known in
the art. Collectors, known in the art, which may be
used in admixture with the collectors of this invention
are those which will give the desired recovery of the
desired mineral. Examples of collectors useful in this
invention include dialkyl thioureas, dialkyl and diaryl
thiophosphonyl chlorides, dialkyl and diaryl dithio-
phosphonates, alkyl mercaptans, xanthogen formates,xanthate esters, mercapto benzothiazoles, fatty acids
and salts of fatty acids, alkyl sulfuric acids and
salts thereof, alkyl and alkaryl sulfonic acids and
salts thereof, alkyl phosphoric acids and salts
thereof, alkyl and aryl phosphoric acids and salts
thereof, sulfosuccinates, sulfosuccinamates, primary
amines, secondary amines, tertiary amines, quaternary
ammonium salts, alkyl pyridinium salts, guanidine, and
alkyl propylene diamines.
` 30 Specific Embodiments
The following examples are included for
illustration and are not intended to limit the scope of
,
34,276-F -23-
-24-
~Z~75~79
the invention. Unless otherwise indicated,
all parts and fractions are by weight. Synergism
is defined herein as when the measured result of a
blend o~ two or more components exceeds the weighted
average results of each component when used alone.
This term also implies that the results are compared
under the condition that the total weight of the
collector used is -the same for each ex~eriment.
i
Example 1 - Froth Flotation of a CopperjMolybdenum Ore
from Western Canada
Bags of homogeneous ore containing chal-
copyrite and molybdenite minerals were prepared with
each bag containing 1200 g. The rougher flotation
procedure was to grind a 1200 g charge with 800 ml of
tap water for 14 minutes in a ball mill having a mixed
ball charge (to produce approximately a 13 percent plus
100 mesh grind). This pulp was transferred to an
Agitair 1500 ml flotation cell ou*fitted with an auto-
mated paddle removal system. The slurry pH was adjusted
to 10.2 using lime. No further pH adjustments were
made during the test. The standard frother was methyl
isobutyl carbinol (MIBC). A four-stage rougher flo-
tation scheme was then followed.
STAGE 1: Collector - 0.0042 kg/metric ton
MIBC - 0.015 kg/metric ton
- condition - 1 minute
- float - collect concentrate
for 1 minute
STAGE 2: Collector - 0.0021 kg/metric ton
MIBC - 0.005 kg/metric ton
- condition - 0.5 minute
- float - collect concentrate
for 1.5 minutes
34,276-F -24-
-25-
~LZ~7~3~9
STAGE 3: Collector - 0.0016 kg/metric ton
MIBC - 0.005 kg/metric ton
= condition - 0.5 minute
- float - collect concentrate
for 2.0 minutes
STAGE 4: Collector - 0.0033 kg/metric ton
MIBC - 0.005 kgJmetric ton
- condition - 0.5 ~inute
- float - collect concentrate
for 2.5 minutes
:
The results are compiled in Table I.
TABLE I
~r
Cu Moly Cu Mo
Collector R_72 R~72 Grade3 Grade3
potassium amyl 0.776 0.725 0.056 0.00181
xanthate1
1,2-epithiooctane1 0.710 0.691 0.093 0.00325
50/50 blend of potas- 0.794 0.766 0.054 0.00177
: sium amyl xanthate
:~ 20 and 1,2-epithiooctane
methyl hexyl sulfide1 0.699 0.697 0.107 0.00386
50/50 blend of potas- 0.790 0.793 0.056 0.00169
sium amyl xanthate
and methyl hexyl sulfide
~,~
1Not an example of the invention
2R-7 is the experimental fractional recovery after
7 minutes
3Grade is the fractional content of specific metal
contained in total weight collected in the froth
The 95 percent confidence region of statistical
error associated with the Cu R-7 experimental values in
Table I is ~ 0.010. Thus the statistical range of R-7
value for Cu in Table I associated with potassium amyl
;`'' .
: .
:
34,276-F -25-
--26--
~26~979
xantha-te is O . 776 ~ O . 010 or O . 766 to O . 786 . The
statistical error associated with the Mo R-7 experi-
mental values in Table I is ~ 0.015. Applying these
limits clearly indicates the recoveries of Cu and Mo at
7 minutes with the collector blends of this invention
exceed the 7-minute recoveries that would be expected
from a weighted average effect of the individual compo-
nent used alone; synergism has occurred.
Example 2 - Froth Flotation of a Copper/Nickel
Ore from Eastern Canada
A copperjnickel ore containing chalcopyrite,
pentlandite, and pyrrhotite minerals was floated using
0.0028 kg/metric ton of DOWFROTH~ 1263 frother and a
collector dosage of 0.28 kg/metric ton. A series of
samples were drawn from the eeders to plant rougher
bank and placed in buckets to give approximately 1200 g
of solid. The contents of each bucket were then used
to perform a time-recovery profile on a Denver cell
using an automated paddle and constant pulp level
device with individual concentrates selected at 1.0,
3.0, 6.0 and 12.0 minutes. The chemicals were added
with a condition time of one minute before froth
removal was started. There was no stage addition of
;~ reagents. Individual concentrates were dried, weighed,
; 25 ground and statistically representative samples pre-
; pared for assay. The results are compiled in Table II.
34,276-F -26-
~ -27-
iZ67~7~
TABLE II
Pyrrho-
Cu Ni tite
Collector R-122 R-122 R-122
sodium amyl xantha-tel O.930 0.839 0.358
1,2-epithiooctane1 0.927 0.751 0.247
dibutyl sulfide1 0.928 0.630 0.190
50/50 blend of 1,2-epi- 0.927 0.844 0.344
thiooctane and sodium
amyl xanthate
50/50 blend of dibutyl 0.931 0.824 0.245
sulfide and sodium
amyl xanthate
1Not an example of the invention
15 2R-12 is the experimental fractional recovery after
12 minutes
.
The recoveries of Cu at 12 minutes are all so
high in Table II (approaching the theoretical limit of
1.0) that the use of statistical confidencQ limits does
not apply. The 95 percent confidence level of the
R-12 values for Ni in Table II is ~ 0.012. It is clear
that the collector blends of this invention give Ni
recoveries that significantly exceed those recoveries
that would be expected from a weighted average of each
component used alone; synergism has occurred.
:'
~ .
Example 3 - Froth Flotation of a complex
Pb/Zn/Cu/Ag Ore from Central
Canada
Uniform 1000 g samples of ore, containing
galena, sphalerite, chalcopyrite, and argentite, are
prepared. For each flotation run, a sample was added
to a rod mill along with 500 ml of tap water and 7.5 ml
34,276-F -27-
-~ -28
1~6797~
f S2 solution. Six and one-half mlnutes of mill time
were used to prepare a feed of gO percent less than 200
mesh (75 microns). After grinding, contents were
transferred to a cell fitted with an automated paddle
for froth removal, and the cell attached to a standard
Denver flotation mechanism.
A two-stage flotation was then performed. In
Stage I a copper/lead/silver rougher was used, and in
Stage II a zinc rougher was used. To start the Stage I
flotation, 1.5 g/kg Na2CO3 was added (pH of 9 to 9.5),
followed by the addition of collector(s). The pulp was
then conditioned for 5 minutes with air and agitation.
This was followed by a 2 minute condition period w:ith
agitation only. MIBC frother was then added (standard
dose of 0.015 ml/kg). Concentrate was collected for 5
minutes of flotation and labeled as copper/lead rougher
concentrate.
The Stage II flotation consisted of adding
0.5 kg/metric ton of CUSO4 to the cell remains of Stage
I. The pH was than adjusted to 10.5 with lime addition.
This was followed by a condition period of 5 minutes
with agitation only. pH was then rechecked and adjusted
back to 10.5 with lime. At this point, the collector(s)
were added, followed by a 5-minute condition period
with agitation only. MIBC frother was then added
(standard dose of 0.020 ml/kg). Concentrate was col-
lected for 5 minutes and labeled as zinc rougher con-
centrate.
Concentrate samples were dried, weighed, and
appropriate samples prepared for assay using X-ray
34,276-F -28-
-29-
~;797~
techniques. Using the assay data, fractional recover-
ies and grades were calculated using standard mass
balance formulae. The results are compiled in Table
llI.
;
.
.
34,276-F -29-
, . .. ...
::
--30--
~7979
, o , o , o
o C`l ~, ~ oo o
~,- ,`
o o o o o o
~ o ,~ ~ .
~ . . o
~ o , o
N ~
~' OOOOOO
~1 ~ ~ , o)
C7 0
o C
O
~ C~
_1 C~ C:~ I O I O
~ O O O O O O ~ i
Cr~ OC~ O 3~ O O
,,"C~io ~ ~ ,~ Ln C C
O ~
¢ ~ ~ q ~ ~ E ~ E E ~,
D 1~ E a~
~ ~ ~ o ~ ~ U
:~ -1 ~ ~ I I I I 0
C
34, 276-F -30-
~ -31-
7g7~
In Table III, then are two -test conditions
which logically allow comparision of the recoveries
associated with the collector blends of this invention
to those recoveries achievable with a component col-
lector used alone.
Comparing the Cu/Pb flotation (Stage I)
Run 2 with collector D used alone verses the Cu/Pb
flotation (Stage I) of Run 3 using the collector
blend D + B, the results illustrate the greater
Ag, Cu, Pb recoveries achieved with the collector
blends of this invention. The 95 percent confidence
level of statistical error is for Ag, i 0.01, for
Cu, i 0.01, and for Pb t 0.02.
The Zn flotation (Stage II) of Run 3
compared to the Zn flotation (Stage II) of Run 2
also illustrates the obvious increase in the Zn
recovery associated with the blend versus that of
the component used alone. The 95 percent confidence
level of statistical error for Zn is i 0.01.
Other runs using single components in
various stages are not repor-ted in Table III as
many of the single components when used alone simply
do not perform adquately enough to collect m~ningful
data for comparison. For example, collector B used
alone in Stage I for Cu and Pb gives less than 0.500
recovery.
Example 4- Froth Flotation of a Complex Cu/Mo
Ore from South America
34,276-F -31-
~ -32
~Z6'79~
A 500 g quantity of a Cu/Mo ore, containing
several copper containing sulfide minerals and moly-
bdenite, was placed in a rod mill having one-inch ~2.5
cm) rods along with 257 g of deionized water and a
quantity of lime. Then the mixture was ground for 360
revolutions at a speed of 60 rpm to produce a size
di~tribution of suitable fineness. The ground slurry was
transferred to a Agitar 1500 ml flotation cell outfit-
ted with an automated paddle removal system. The
slurry was agitated at 1150 rpm and the pH adjusted to
the appropriate value ~shown in Table IV) with either
more lime or hydrochloric acid
At this point, the collector(s) were added to
the float cell (45 g/metric ton), followed by a condi-
tioning time of one minute, a-t which time the frother,
DOWFROTH~ 250 was added (34.4 g/metric ton). After an
additional conditioning time of one minute, the air to
the float cell was turned on at a rate of 4.5 liters/-
minute and the automatic froth removal paddle was
started. Samples of the froth were collected at 0.5,
1.5, 3.0, 5.0, and 8.0 minutes.
The samples were dried overnight in an oven
along with the flotation tailings. The dried samples
were weighed, pulverized to a suitable degree of fineness
for dissolution, and dissolved in acid for analysis on
a DC Plasma Spectrograph. The results are compiled in
Table IV.
34,276-F -32-
--33--
~i79~7~
o ~ ~
o ~ ~ oo
`: I ~ ~ o o o
a~l o
I~ ,_1
,, ~ ~ , oo o
~ ~ . ~ ~ o ~ o
C~o o o
U~ U~ ~ o o o
o o o oo oo oo
.
~_ h
C 3~
J-
H ~1~ /~ ~ ';t~ 1--- 1~ 1` ~ ~ ~ 1_
~~ U ~ P
a o
.C `
~: d~3~ v
P~ p~ J ~ ~
h ~:: ~q ~ 6 h U~ ~ E ~ ~ 6 s~ ~ v
O ~ O ~ ~ O ~ 3 0 P~ ,~ O p~
, v ~ ~ ~,1 u ~ ~ ~1 V p~ ~a rl V ~ ~3 ~rl V O ~U
~1 ~ O~ ~J O ~1~ U O ,Q~ ~ O D~
i O 0 6 o o 6
O S,l ~ 3.--1 1.1 1;~ ~ ~ h ~ l h d ~ l H C)
C~ 0~ r~ 04~ ~ o~"~ 0~-,~ 6P'
~a ~ o ~~ o ~ ~ 1 0 J~ ~ 0 ~) ~ S
., N
34, 276-F -33-
-34-
~267~7~
The recoveries of Cu at 8 minutes are all
so high in Table IV (approaching) the theoretical
limit of 1.0) that the use of statistical confidence
limits does not apply.
5THe 95 percent condifience level of
statistical error or Mo recovery at 8 minutes is
0.012. Clearly, the collector blends of this
invention provide Mo recoveries that significantly
exceed those recoveries that would be expected
from the individual components used alone. For
example, the Mo recovery of Run 3 clearly exceeds
that expected from the weighted average of Runs
1 and 2. Synergism has occurred.
: '
34,276-F ~34~
