Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1077637 ~;
. .
**~;***:***** ~
Tl~is application relates to the production of
polymeric flocculating agents.
Wat:er soluble polymeric substances in powder
form use-l as ~locculation, sedi~ ntation, dehydration and
retcntion a~juvallts arc kno~n. l'llus, in U. S. Patent
3,539,5~5 ~ erc is (3escri.bed a metllod oE obtaining solid,
~' .
.
.
' q~
:,.. , ' . :
`~ ~077637
ca~:ionically ac~:ive ~)olymers, in wllicll a polyacrylic amide
suspension in an or~anic solution is prepared witllout the
use of a~l elllulsiEier. This unst:able suspension is then
react:ed ~11ith formaldellyde and secon:lary amines to the
~lannich base, and the lat:ter is isolated in solid form
by precipitation wi~ suitable solvents.
I~ is kllown that the great:er are the molecular
wèights oi~ the ~.ater soluble polymeric substances in
powder fonn, the more effective they are. The high
molecular ~7eights, however, make the preparation of
ready-to-use solut:ions OL~ the water-soluble, powdered
substances time-cons-lllling and difficult, i.e., one is not
al~ays assured that the solution rèady for use will be
particlc-free. In addition, the use of po~dered products
entails tecllllical difficul~y, and e~pensive apparatus
is required for tl~e continuous, constant proportioning
thereof.
All of these difficulties are obviated iE liquid
or at least pumpable products are used, and efficiency
requires t hat the content of active substance in such
liquid or pumpab]e products must be as great as possible.
According to Gernan D0~ 2,048,664, 2,054,523,
2,156,858, 2,206,564 and 1,546,344, the preparation and
- - use of aqueous solut~ions of polyacrylic anlide ~falmich
bases is known, such bases bein~; obta ined by the
1077~;37
aminon,e~llylation of the acid amide groups of dissolved
pol~,leric pro(l~lcts ~ith omla]dehyde and amine.
I~owever, as a consequence of the high degree of
polymerization of the polyacrylic amide or of the state
of this polymer in aqueous solution, as the case may be,
only relatively dilu~e solutioll~s, i.e., solutions
containing 5 to 10% by ~eight, can be prepared by these
methods. The solutions even at this lo~ content have a
high viscosity. The viscous liquid products prepared by
the above methods are therefore difficult to pump or to
handle, so that their use in a number of areas is
restricted in spite of their good effectiveness.
In the case of long storage, and also in attempts
to dehydra~e these products or to prepare them with a
larger content of active substance, it has been found
that they cross-link to form largely insoluble and thus
ineffective substances.
In a process described in German DOS 2,163,246,
the production of polyacrylic amide Mannich bases is
accomplished by further processing the 5% to 10% aqueous
polymer solutions obtained by the previously described
methods. Specifically, by the addition of polyvalent
electrolytes the polymers are caused to precipitate from
the dilute solution but the separation of the aqueous
phase and the drying of the product is, again, expensive.
~ 1077637
Also hno~n are so]id, free-flotJing flocculation
composi~ions formed in accordallce with German DAS
1,442,39~ from polyacrylic amidc and tlle reaction product
of dialkyla~mnonium salts ancl paraformaldehyde, which
become cationically active in the dissolved state in a
medium having a suitable pll value.
It is accordingly an object of the invention to
provide an ine.Ypensive process for the preparation of
pumpable solutions of flocculating agen~s which have
a high concentration of active material.
Tbese and other objects and advantages are
realized in accordance with the present invention
pursuant to whicll there is provided a flocculation,
sedimentation, dehydration or retention composition
comprising a dispersion of about 10 to 50% concentration
by weiOht of a polymeric ~Iannich base in a mLxture of
water and a water-insoluble liquid, the ~annich base
comprising an }I-active polymer carrying radicals of a
reaction with formaldehyde and a primary or secondary
alkyl- or hydroxyalkylamine wherein the alkyl groups
have up to about 18 carbon atoms.
These compositions, preferably having a
concentration of about 25 to 35% by weight, may be obtained
by dispersing in a water-in-oil emulsion a water-soluble,
hydrogen-active substance of high molecular weight in
a concentration of about 10 to 50% by weight, and
reacting the dispersion thus obtained, under the conditions
-4-
1077637
of the Mannich Reaction, with monomeric and/or polymeric
formaldehyde, preferably with the use of an aqueous form-
aldehyde solution emulsified in the organic phase, and a
primary or secondary amine. At the same time, the possibil-
ity exists of controlling the content of the polymeric, water-
soluble Mannich base in the end product by using amounts of
formaldehyde and amine which are equivalent or subequivalent
to the dispersed polymeric hydrogen-active compounds. It has
additionally been found that the products of the invention
are likewise obtained by suhjecting water-soluble monomeric
Mannich bases to polymerization in a water-in-oil emulsion.
Substances which can be dispersed in a water-in-
oil emulsion and which are accessible to the Mannich reaction
are hydrogen~active compounds, especially acrylic amide and
methacrylamide as well as polymers or copolymers thereof with
other polymerizable compounds, that is NH-active polymers
carrying carbonamide groups. Especially suited are polymers
and copolymers of acrylamide such as polyacrylamide and co~
polymers of acrylamide with acrylonitrile, salts of acrylic
acid, esters of acrylic acid, styrene, vinyl acetate, vinyl
chloride, vinyl pyrrolidone, vinyl imidazole and/or vinyl
pyridines.
Amines suited for the reaction include those which
carry active hydro~en such as amines of the fDrmula
.~ , .
- 5 -
-
,
~, . .: ,.
1077637
R-Nl~2 and/or R-N~ ' whereill K and R' are alkyl or
hydroxyalkyl radicals with 1 to 18 carbon atoms. For the
purposes of the invention those amines are preferred which
have straigllt chains of not more than about 8, preferably
not more than about 6 carbon atol~. Suitable amines,
for example, include methylamine, ethylamine, propylamine,
butylamine, pentylamine, hexylamine, heptylamine and
octylamine. Of the straight chain amines suited for the
practice of the invention the secondary amines are
preferred. Especially preferred secondary amines include,
for example, dimethylamine and diethylamine. Diethanol-
amine is an example of a hydroxyalkylamine suitable
for practice of the invention.
For the pre~aration of the stabilized system
for the dispersion of the water-soluble, hydrogen-active
monomers, polymers and/or copolymers, a water-in-oil
emulsion is used. Aliphatic and/or aromatic hydrocarbons
are usable as the oily phase. The water-in-oil emulsion
is obtained by the use of emulsifiers of a suitable HLB
number, especially sorbitan esters and other oil-
soluble fatty acid esters, such as fatty acid polyglycol
esters.
It is a special advantage of the products
obtained by the above-described process that the
concentration of active substance amounts to about 10 to
50%, generally about 30-lo~ by weight, that the dispersions
-6-
. .
~ ~ :. . ~ ~ S r _ . . .. _ . . _ _ ,,__, __,, ,_ _
- 1077637
are stable, ancl ~llat the prcpclration of solu~ions of
these dispcrsions ready for use can be accomplislled
without great teclm ical expenditure, e g., by means of a
proportioning p~np, the polymeric product going rapidly
and completely into solution upon dilution with water,
withou~ thc use of additional wetting agents.
The process described herein offers appreciable
advantages over the above-described previously known
processes.
The products prepared b~, the present method
have technical applications in a variety of
areas. They can be used as sedimentation or flocculation
adjuvants in heterogeneous liquid-solid systems> as for
example in the sedimentation of aqueous sludges containing
minerals, and as dehydration and retelltion agents. In
this mamler also the use of such water-in-oil suspensions
is possible in systems containing water, but containing
mainly nonp~lar liquids.
The m~nufacturing process and the application
of the products thereof will now be further explained with
the aid of the following examples wherein all parts are -
by weight unless otllerwise eYpressed.
T~le organic, hydropKobic phase (I) used in
Examples 1 to 10, which is an important component of the
product, may be obtained, for example, from:
-7-
'
.
` 1077637
13~ parts n-paraffin of the following characteristics:
~oiling range: 195-225C
Density: 0-740
l'ercentage of hydrocarbons in
the mixture:
C10 t~ ~ wt.-~
Cll to 3~ wt._,o
C12 to 37 wt.-~
C13 to 16 wt.-~
18 parts sorbitan monooleate and
12 parts stearic acid polyglycol ester containing
ten moles of ethylene oxide per mole of stearic acid,
.by mixing the parts together.
Example 1:
I're~aration: ~3.1 parts of 60~ aqueous dimethylamine 501u-
tion emulsified in 16.9 parts of organic phase(I) are
stirred into 140 parts of a polyacrylamide latex pre-
pared by radical polymerization in a known manner from
3,135 parts of acrylic amide dissolved in 2?660 parts
water, the whole emulsified in 4~104 parts of organic
phase(I). After about 60 minutes a second emulsion, con-
sisting of 23~1 parts of aqueous 40% formaldehyde solution
and 16.9 parts of organic phase(I) are added in portions
with stirring, such that the temperature of the mixture
is not caused by the heat of the reaction to exceed 40DC.
The reaction has ended after ~ hours and the product is
obtained as a fluid, colorless but turbid polymer suspen-
sion having a polyrner-Mannich base content of 27.9/o by
weight.
.
1077637
~x~m~ le ):
!~re~ar.l tiorm 2~0 j!arts of t?-e same ~olymer latex as in
Ex~mple 1 are mixcd witil 9.0 ~arts of ~ ~O'`o, a~lueous di-
methylaminc solution, ~.7 parts of diet~ylaminc and 0.3
p~rts ~later in 12 parts of or~nic phase(I), and then re-
acted with 17.9 p~lts of 40,o a~ueous formaldehyde solution
in 12 parts of or~n;c phase(I) in the sarne manner as de-
scribed in ~xarn~-le 1. ~ polyacrylamide~ nnich base
suspension is obtained h2ving .~ cor)tent of 32.7~o water-
soluble poly~ers.
Ex~mple 3:
l~repar~ltion: 13~).3 parts of tlle same polyacrylamide latex
as in Example 1 are reacted with a total of 45.2 parts
of a 60~/o dimeth~lamine solution, in 2~.~ parts of organic
phase (I) and a total of 45.2 parts of aqueous 40% formal-
dehyde solution in 28.2 parts of organic phase (I), the
procedure being such that first one-third of the amine
emulsion is stirred into the polymer latex and, 20 minutes
later, with conti~iued stirring, o~e-third of the aldehyde
emulsion is added. The temperature of the mixture in the
meantime is not to exceed 40C, After a reaction time of
an additional 30 minutes the second and then final thirds
of the amine and aldehyde emulsions are completely reacted
separately in the same manner using the same timing. A
fluid, clear product is obtaincd, which is soluble in
water. Active substance content: 26 3% by weight.
~077~37
Ex.lmi)1e ~:
Pre~ r~io~ 6 l~rts of diet~!yl~mine are added to 128
p~rts of acryllc amide dissolved in 10~ parts of water.
67.5 parts of a~ueous 40,0 formal~e~lyde solution are added
to the mixture in portions sucil that the temperature in
the mixture is not increased above fiOC by the heat of
the reaction~ 50 parts of organic phase(I) and 11 parts
of wate~ are addcd to 63 parts of the resulting solution
of carbamoylmethylamine and acrylic amide in a ratio of
approximately 0.6 : 0.4 in water. The mixture is stirred
to form an emulsion and is satu~ated with oxygen~ A redox
system, consisting of 0.023 wt~-,' ammonium peroxydisulfate,
0.023 ~t.-,~ potassium bisulfite and 0.004 wt.-~ (with re- -
spect to the monomer) of iron(II) sulfate, is added, and,
by polymeriz~tio~ fo~ 10 hours at 35C, a suspension of
polyacrylamide and Mannich base is obtained. Active sub-
stance content: 28 2% by weigllt.
Example 5:
300 parts of 31~35~/o polyacrylamide latex
produced according to ~xample 1 are reacted incrementally
at room temperature with a wa~er-in oil emulsion produced
by combining 138,5 parts of diethanolamine, 50 parts of
water, 99,5 parts of 40% formalin and 148 parts of
organic phase (I) with cooling. After a reaction time of
5 hours there is fonned a cationically active polymer
suspension of 33.7% concentration.
. .
Example 6:
In the same manner as described in ~xample S~
200 parts of a polyacrylamide la~ex is reac~ed with a
-10-
~ . .. . . ... ...
7637
wa~er-in-oil emulsion Eorllled of 77.5 parts ~f 40riO methylamine,
6G.0 paLts of 40~ ~ormalin and 120 0 parts of organic
phase (I). The product con~ains 22,8~/o of active material.
Example 7:
A copolymer latex is prepared in known manner
by radical polymeri~ation o~ 75.0 parts oE acrylamide
and 25~0 parts of dimcthylaminoethyl metllacrylate
hydrochloride, the copolymer being emulsified in 140.85
parts of water and 117.5 parts of organic phase (I).
300 parts o~ this 28% copolymer latex are reacted with
5 parts of a water~ oil emulsion made from 50 parts
of 60V/~ dimethylamine and 40 parts of organic phase (I).
The p~l of the resulting latex rises to 8Ø 20 parts of
60% diethylamine, 20 parts of 40~/O formaldehyde and
20 parts of organic phase (I) are mixed with cooling and
this mixture, which is a water-in-oil cmulsion, is added
dropt~ise to tlle copolymer latex, After 5 hours there is
formed a polymeric ~lannich base suspension of 28,5V/o
concelltration.
Example 8:
99 5 parts of 60~/o dimetllylamine solution and
99 5 parts of ~0^/0 formalin are combined with cooling and
emulsi~ied by stirring witll 96 parts o~ organic phase ~
.The resulting water-ill-oil emulsion is added with stirring
oE the reacti.on m ~ture to 316 parts of a 31% pol~ler latcx,
~77637
which la~:ex is p~-oduccd by copolymerizitlz 95 par~s of
acrylamide and S par~s of acrylonitrlle in a water-in-oil
e~ulsion accordillg to the proccclure of Example 1. The
reaction mi~ture is maintained wi~ll stirring for 5 hours
at room temperature wlereupon there is formed a cationically
active produc~ of 28,3~ concentratioll.
S0 parts of organic phasc (I) and 11 parts of
water are added ~o 63 parts o the resulting solution of
carbamoylmethylamine and acrylamide in a ratio of
approximatel~ 0.6 : 0.4- in water The mLX~ure is stirred
to form an emulsion and is saturated with oxy~en. A
redox system, consisting of 0.023 ~t.-V/~ ammonium peroxy-
disulfate, 0.023 wt.-% potassium bisulfite and 0.004 wt.-%
(with respect to the monomer) of iron (II) sulfate, is
added, and, by polymcrization ~or 10 hours at 35C, a
suspension of polyacrylamide and ~lannich base is obtained.
Active substallce content: 28 2% by weigl~t.
Example 9:
In l~nner analo~ous to ].~ample 1, there is
prepared a water-in-oil emulsion from 67.5 parts of 40%
~ormalln, 67,5 parts o~ 60 ~ dimethylamin and 100,0 parts
o~ organic pha~e (I). The
emulsion is added with stirrin~ ~o a polymer latex
produced by radical polymerization o a monomer emulsion
comprising 80,0 parts o~ a~rylamide and 70.3 of 2-vinyl-5-
pyridine and quaternizing with 9~7 parts of dimethyacrylate,
the latex also conLainin~ 2~0 parts o~ water and 350 par~s
o reaction phase (I) There forms a cationically active
-12-
~ . . , .. , - - , . . . . . .
`` 1077637
po1ym~r susl)ension ll~vin~ a collcen~ratiolt of 16~S~/o
E.~
~ copolynler latex is produced rom 20 parts of
acrylamide, 7.8 p~3rts of vinylpyrrolidone, 50.0 parts o~
~ater and 7404 parts o~ organic phase (I). 152 Parts of
this latex are reacte~ at room tempcrature witll stirring
witll a ~ater-in-oi1 ~mulsiol~ prerared l-~ mixing 10~6 parts
of 60'~o dimethylarnil-e ~ 10~ 6 par~s o~ 400~D formalin and
15.7 parts of organic phase (I) with cooling. After 5
hours of reaction there is formed a l9~0~/o suspension of
the ~fanni.ch ~ase.
~xarnp1e 11:
The products made by the method of the invention
were tested as sedimentation agents in flocculation ex-
periments. The flocculation performance of polyacrylamide-
Mannich base mi.xtures in aqueous solution was tested by
determining the settling time after adding them to aqueous
clay suspensions which had been prepared by mixing kaolin
with water in the conventional manner and had been adjusted
with Al2(S04)3 solution to a pH of approximately 4.8. The
results a~e set forth in Table I:
Table I
Product Time (sec.) Product _ Time (sec.)
None 180 per Example 6 9,3
per Example 1 11 J7 per Example 7 10,4
per Example 2 13J8 per Example 8 9,1
per Example 3 11 J 6 per Example 9 11 J 6
per Example 4 15J~ per Example 10 12J7
~ . ._
-13-
.
: : - - . - : ~
10~76~3~
t
~able l~ 0cculatioll effec-t orl a clay suspension
contaillirlg 20 g of solids ~er liter plus ~12(SO4)3
additive, product in O.l,' solution; concentration 4 ppm.
On the performance of the tcsts, see tl. Akyol and
M. Neven: Chemie-Ing~-Tec}lnik 3'~ (1967) 172.
Example 12:
In the same manner, polyacrylamide-~annich base suspen-
sions are usable in the process of the clarification of
titanium extraction solutions--so-called ~black 'solutionsn--
which represent ar) intermediate in the production of titanium
dioxide pigments from ilmenite or ore slags.
7.5 ml of an O.l~o solution of the product of Example
3 is adde'd to one liter of titanium extraction solution.
After the addi-tion of the flocculation agent, the specimen
is shaken for 15 seconds and transferred to a one-liter
measuring cylinder.
The activity manifests itself in a rapid floccula-
tion; settling speed: 6 meters per hour. The floccula-
tion effect can also be judged on the basis of the gray
filter scale values listed in Table II and on the basis
of the flocculation quality, the product of Example 3 being
compa~ed ~ith a commercial flocculation agent based on
t'rimethylarnmoniumethyl methacrylate which had been used
formerly in the clarification of "black solutions."
,
~ -14-
`~077637
. Tatlle II
Flocculation ayent Gray filter scale (residue in
mg in 50 ml of supernatant
solution)
After 30 60120 min.
.
~roduct of ~xample 3 9 7 5
~roduct base(~ o-- tri- 11 10 8
metllylammoniumethyl
methacrylate __
Examnle i3:
. .
The studics described hereinafter will serve to ex-
plain the applicability of the p~oducts as dehydration and
retention agents in the manu~acture o~ paper.
StaIting out with standaIdized cellulose .suspensions
of the following composition:
~ Bleached cellulose, spruce and beech 70:30
Concentration: 3 grams pcr liter
Fineness of grind 6~S.R.
Pigmentation: 25% china clay with respect to
cellulose
Sizing: 1~ resin glue acidified with
. 35' A12(S04)3 to pH 6.5 to 6.8
the rate of dehydration was measured as the change in the
fineness of grind in degrees by the Schopper-Riegler method
(S.R.) as a function of the amount of pIoduct added, and
the xetention capacity of these products was measured by
gravimetric determination of the solid content in the
discharge of a sheet former ("Rapid-Kothen"). The results
are summarized in Table III.
-15-
... . . . ..
._ . ,,, .,. ~, . . ... .. . ...... . . . . ..
-
1077637
Tahle III
Dehydration tests ~etention test
Einerless of grind Solid content of
Adjuvant (SR) upon the ad- screen water
dition of:
100 ppm200 ~rm300 D~m 100 ppm 200 ppm 300 ppm
Product of
Example 1 57 53 47 156 132 129
Product of
Example 7 59 55 50 16~ 14~ 135
Copolymer of 60 58 54 176 152 146
Acrylic amide
and trimethyl-
ammoniumethyl-
methacrylate
~iithout additive 69SR
It is found that the pIoducts prepared in accordance
with the invention are effective under these experimental
conditions, which are largely in accordance with the test-
ing methods used in paper technology~ Since the products
are furthermore very fluid and therefore easy to handle,
î.e., easy to proportion and easily soluble, they can be
prefeIentially used in the manufacture of paper.
Example 14: - ` -
The described products can be used equally well inthe dehydration of communal sludges.
Dehydration test using activated sludge:
Solid content: 8.3~
Dehydration Amount added Solids in Concentrate
agent (g/m3) discharge Appear_ Extinction
) ance (xlO0)
. . , _ .
Product of
Example No. 1 93 31~1 white 20
C~polymer based
on acrylic amide 220 30.2 very 100
trimethylammo- turbid
niumethylmeth- -
acrylate
Produ~t o~
Example No. 6 105 32,4 white 22
Product o~ -
Example No. 7 98 ~1,4 white 20
, . .. . ~ . ..
1~763'7
As can be seen in the foregoing examples, the
formaldehyde and amine are employed in approximately equimolar
amounts. The H-active monomer unit, e.g. acrylamide, may be
present in about 1 0 or more times the formaldehyde molar
amount. The molecular weight of the polymeric material
desirably exceeds about 5Q,QQQ and preferably exceeds about
lQO,OOQ. As employed in the appended claims, formaldehyde
embraces polymers thereof such as trioxane.
It will be appreciated that the instant specif-
lQ ication and examples are set forth by way of illustration and
not limitation, and that various modifications and changes
may be made without departing from the spirit and scope of
the present invention.
- 17
. ' :
: ' , ' ~ ' ;
. .: ~ :
