Note: Descriptions are shown in the official language in which they were submitted.
~063944
The present invention provides a new process for
the purification of industrial effluents, in particular the
decolourisation of waste water occurring in the textile,
fibre, paper, and leather industry, and in the manufacture of
fluorescent brighteners and dyes, for example, residual
liquors, mother liquors, rinsing and wash waters.
One of the grea~environmental problems in industrial-
ised areas is the pollution of rivers and lakes. Because the
pollution can also originate from industrial plants, the
purification of industrial effluents is gaining increasing
importance at the present time. However, this effluent
purification is proving to be exceedi~ngly difficult, especially
whenever it is a matter of eliminating organic substances of
limited biodegradability which are dissolved in water. Within
this nexus of problems there is consequently an urgent need
- for the decolourisation and purification of effluents which
occur in the dyestuff, fibre, textile, paper, and leather
industry.
Different processes have already been proposed for
the purification of strongly coloured and polluted effluents
that occur for example in the manufac~ure and use of dyes
and dyeing assistants. It is known, for example, to collect
coloured effluent or wash waters in large tanks and to
precipitate the dyestuff and assistant residues by addition
2- ~
1063944
of suitable flocculants and to separate them by sedimentation,
flotation or filtration. However, these processes create
problems, because the quantities of water to be treated are
large and the sedimentation or the separation of the flocks
from the purified water involves the use of complicated
apparatus.
It is also known to use activated charcoal for
purifying, especially for decolourising, industrial effluents.
The use,for example, of granulated activated charcoal often
proves to be not very suitable, since the capacity of the
activated charcoal for absorbing organic dyes dissolved in
water and impurities present in effluent is too small.
From US patent 3,716,483 it is also known that
industrial effluents can also be purified with the aid of
highly disperse organic polymers which are in the dry state.
However, the drawback of this process is that, for example,
the removal of anionic dyes from aqueous liquors in a satis-
factory amount is only possible at elevated temperatures and
relatively low pH values.
Surprisingly, it has now been found that a rapid
and ample purification of industrial effluents is attained
by bringing them into contact with a polymeric adsorption
material in the form of a solvated, preferably hydrated, gel.
Compared with the corresponding non-solvated and non-hyd-
-- 3 --
', ' ' . :
- ',' " , :.' ,. : " . '., .: .
1063944
rated materials, this polymer gel adsorption material is
characterised by an increased capacity for adsorbing sub-
stances that are dissolved or dispersed in water and by an
increased rate of adsorption.
The adsorption material to be used according to the
present invention is suitable above all for purifying liquors
containing ionic, i.e. anionic or cationic, substances and
mixtures thereof, in particular for removing anionic or
cationic dyes, fluorescent brighteners, dyeing or textile
assistants, surfactants, tannins, or mixtures thereof.
With the aid of ~he adsorptive polymer gels it is
possible not only to remove the previously mentioned sub-
stances from incompletely exhausted dye, brightener and treat-
ment liquors, but also to purify to a satisfactory extent the
corresponding residual liquors that contain non-ionogenic
textile or dyeing assistants and/or non-ionic dyes or
fluorescent brighteners and also liquors which are diluted
by rinsing waste waters and normally contain mixtures of
dyes and detergents.
On account of the broad applicability of the
adsorption material used in this invention, it is possible
to meet the nowadays ever more urgent demand for saving fresh
water by a partial to complete recirculation of residual or
waste liquors. Independently of the apparatus used, these
-- 4 --
1063944
are principally the effluents of the dyestuf, fibre
manufacturing, textile, paper, and leather industry, which
occur in connection with dyeing, washing and tanning pro-
cesses. In the case of a dyeworks, these effluents can ori-
ginate from the conventional dyeing machines used for thedyeing of loose fibrous material, tops, yarn, and woven and
knitted fabrics, and also from rinsing machines, e.g. an
open-width washer.
The purification of the effluents is advantageously
carried out at 0 to 130C. Preferably, however, it is
effected at temperatures between 0 to 100C, in particular
between 10 and 70C. If desired, the effluents can also be
purified under pressure or in vacuo. The pH of the liquor
can vary within wide limites, for example between 2 and 12.
Depending on the nature of the polymer used as adsorption
material, pH adjustments, for example to a value of 2-to 7,
in particular of 3 to 5, can simplify and speed up the
purification process.
The process of the present invention can be carried
out discontinuously, semi-continuously or continuously, the
last two alternatives being preferred. In principle, the
following three processes are suitable within the scope of
the invention:
a) the stirring process, in which the water to be
:, ' ' . :, '
~ .~
'; :
'. ' , ', ~
1063944
purified is stirred in a vessel with the adsorp-
tion agent and then the ~wo are separatedi
b) the fluid bed process, in which the adsorption
agent is kept in suspension through the flow of
the liquor to be purifiedi
c) the solid bed process. in which the liquor
subject to purification is conducted through a
filter-like adsorption material.
If the last of these three process possibilities,
the solid bed process c), is applied, then the following
three alternatives with respect to the apparatus employed
- are chiefly suitable:
1. The treatment apparatus, e.g. dyeing appliance,
is firmly connected to the filter device.
2. The adsorber device is movable and can be
coupled as required with any treatment apparatus.
3. The effluents originating from the treatment
apparatus are combined in a suitable container and
then jointly conveyed through the adsorption
material.
Within the scope of the invention, suitable polymer
gel adsorption materials can be both natural and regenerated
or synthetic man-made polymers. Preferably they are synthetic
plastics which are non-ionogenic or contain in particular
-- 6 --
1063944
groups which form ionogenic salts in water. such as anionic
water-solubilising groups, for example sulphonic acid, carbox-
ylic acid or phosphonic acid groups, or onium groups, for
example ammonium, sulphonium or phosphonium groups. The
suitable polymers will usually have an average molecular
weight greater than 500 and a specific surface area greater
than 30, in particular 80 to 250 m2/g.
The polymer gel concentration depends normally on
the nature and concentration of the substances to be removed
and is usually 0.1 to 50 g/l, referred to the solids content
of the adsorption material. The polymers used as adsorption
materials are microporous gels in a state of primary swelling,
by which is meant the amount of liquid, for example of water
or organic solvents, which cannot be removed ~or example from
a swollen fibre by conventional mechanical means, for example
centrifuging. This gel state is characterised in particular
in that the specific surface area of the polymer material
falls to values below 5 m2/g of dry polymer when it is dried
by conventional means and the material loses its high absorb-
- 20 tive capacity in the process. Drying by conventional means
is to be understood in this context as meaning that the
swelling liquid is removed at temperatures above its solidi-
fication point by evaporation or volatilisation. The minimum
residual moisture which is necessary for maintaining the gel
-- 7 --
.,
., ,
, ,. ,: ,
1063944
state is as a rule between 5 and 25%, referred to the dry
polymer material.
Also included within the scope of the present
invention are dehydrated polymer gels which are prepared,
for exan~ple, by lyophilisation or solvent exchange drying
while retaining a large specific surface area.
The gel state is achieved, for example, by dissolv-
ing the polymer, if appropriate at elevated temperature, in
a water-miscible organic or inorganic solvent, for example
aqueous nitric acid, sulphuric acid or sodium thiocyanate
solution, and adding the polymer solution to a suitable coag-
ulating liquid, preferably water, or also ethanol, which is
miscible with the polymer solvent but is itself not a solvent
for the polymer and solvates the polymer. In certain cases,
however, the polymer gels can also be obtained direct in the
formation of the polymers.
Examples of water-miscible organic solvents for
preparing the polymer solution are: dimethyl formamide,
diethyl formamide, dimethyl acetamide, ethylene carbonate,
dimethyl sulphoxide, ~-butyrolactone, tetrahydrofuran, acetone,
dioxan, methanol, ethanol, propanol, isopropanol, butanol and
thioglycolic acid.
The polymer solution can be coagulated direct or
separately in the effluent medium. In the latter case, the
- - 8 -
1063944
polymer gel is preferably freed from solvent and coagulating
agent and then brought into contact with the effluent.
The gel state can also be obtained by spray
coagulation, whereby a fine spray of the polymer solution
is added to a fine spray of coagulating liquid. The coagulating
liquid can also be in vapour form. A further possibility of
achieving the gel state consists in atomising the polymer
solution within the coagulating liquor.
The plastics which can be converted into the
required gel state can belong to a wide variety of known
classes of regenerated man-made and synthetic man-made
polymers. Suitable examples are polycondensates, polymers
and polyadducts, which can be both thermosetting plastics
and thermoplastics. Suitable regenerated man-made plastics
are, for example, cellulose esters, such as cellulose nitrate,
cellulose acetate, cellulose triacetate, cellulose aceto-
butyrate, cellulose propionate, cellulose ethers, such as
methyl cellulose, ethyl cellulose and benzyl cellulose, and
also starch derivatives, for example acetyl starch. Advantage-
ously they are synthetic man-made thermoplastics which can
; be used as filament cable, fibre webs, fibre waste, sponges,
loose fibres, slivers or wads, as well as beads, granulates
` or amorphous particles.
Examples of suitable thermoplastics are: polyacrylo-
~06~944
nitrile, polyamide, linear polyesters, for example polyethylene
terephthalate, polyolefins, for example aluminium-modified
polypropylene, polystyrene and polyurethanes.
According to the present invention, synthetic
fibres which are obtained for example, in wet spinning
processes are used as adsorption material for purifying dilute
dye-containing effluents, in particular effluents which are
polluted by cationic and/or anionic dyes.
These wet spun fibres can be unstretched, partially
stretched or fully stretched, and are freed from spinning bath
chemicals by rinsing treatments.
Particularly suitable adsorption materials are
synthetic fibre materials in the gel state the individual
fibres of which have a titre of 0.2 to 20 denier, preferably
of 0.5 to 5 denier.
Materials with a very satisfactory adsorptivity
are comminuted, for example cut or broken, spinning cables
in the moist gel state, with, for example fibre lengths of
1 to 100 mm, preferably 1 to 10 mm. If desired, the spinning
cables can be further refined by grinding.
As preferred synthetic organic fibrous materials
which can be used according to the pxesent invention in the
gel state there may be mentioned: synthetic polyamides, in
particular those obtained from adipic acid and hexamethylene-
- 10 -
,
'
"
,, , ~.
1063944
diamine, from ~-caprolactam or from ~-aminoundecanoic acid;
anionically modi~ed polyamides, such as polycondensation
products of 4,4'-diamino-2,2'-diphenyldisulphonic acid or
4,4'-diamino-2,2'-diphenylalkanedisulphonic acid with poly-
amide-forming starting materialsi polycondensation products
of monoaminocarboxylic acids and the amide-forming derivatives
thereof or of dibasic carboxylic acids and diamines with
aromatic dicarboxysulphonic acids, for example condensation
products of -caprolactam or hexamethylenediammonium adipate
and potassium-3,5-dicarboxybenzenesulphonate; cellulose ester
fibres, such as cellulose 2 1/2-acetate or cellulose tri-
acetate fibresi linear polyester fibres, for example those
obtained by condensing terephthalic acid with ethylene glycol
or isophthalic acid or terephthalic acid with l,4-bis-(hydro-
xymethyl)-cyclohexane, and copolymers of terephthalic and
isophthalic acid and ethylene glycol; acid-modified polyester
; fibres, such as polycondensation products of aromatic poly-
carboxylic acids, for example terephthalic acid or isophthalic
acid, with polyvalent alcohols, for example ethylene glycol,
and 1,2- or 1,3-dihydroxy-3-(3-sodium sulphopropoxy)-propane,
2,3-dimethylol-(3-sodium sulphopropoxy)-butane, 2,2-bis-(3-
sodium sulphopropoxyphenyl)-propane or 3,5-dicarboxybenzene-
sulphonic acid or sulphonated terephthalic acid, sulphonated
4-methoxy-benzenecarboxylic acid or sulphonated diphenyl-4,4'-
- 11-
10~:;3944
dicarboxylic acidi polymeric or copolymeric acrylonitrile
materials, the copolymers containing as a rule at least 50%
of acrylonitrile. Other vinyl compounds, for example vinyl-
idene chloride, vinylidene cyanide, vinyl chloride, methacryl-
ates, methyl vinyl pyridine, N-vinyl pyrrolidone, vinyl acetate,
vinyl alcohol, acrylic amide, acrylic acid, vinyl- or styrene-
sulphonic acid, are also used as comonomers besides the
acrylonitrile.
The adsorptivity of the cited polymer gels can be
regulated by the choice of the monomers or comonomers required
for obtaining them and increased by adding suitable additives
to the polymer solution, for example open-chain or cyclic,
polymerised or unpolymerised amines or ammonium salts. These
additives are able not only to increase the adsorption pro-
perties, but also the solvation and hydration capacity of thepolymer gel.
If the polymer material is one that is obtained by
a process commonly employed for manufacturing textile fibre
cable, then the fibre-like material need not have a high
strength or homogeneity. Consequently the comonomers and/or
spinning solution additives can be much more freely chosen
than in the manufacture of textile fibres which must meet
the demands made of them in respect of textile technology.
If the material is spinning cable which is also, or
- 12 -
10f~3944
especially, manufactured for textile use, the field in ~7hich
these materials can be used in the hydrated gel state is
widened
Possible dyes which can be removed from the effluents
with the adsorption material according to the invention are
anionic or cationic dyes that are both soluble and dispersible
in water, fluorescent brighteners. The adsorption material
is preferably used for removing water-soluble, in particular
cationic and anionic, dyes or fluorescent brighteners.
The anionic dyes which are removed according to the
invention are dyes whose anionic character is dependent on
metal complex formation alone and/or on the acid substituents
which effect the water-solubility. Suitable acid substituents
which effect the water-solubility are carboxylic acid groups,
phosphoric acid groups, acylated sulphonic acid imide groups,
such as alkyl- or aryldisulphimide groups or alkyl- or aryl-
carbonylsulphimide groups, alkyl- or arylimide groups, sulph-
uric acid (half) ester and above all sulphonic acid groups
The anionic dyes can belong to the most widely
different classes of dye. As examples there may be mentioned
oxazine, triphenylmethane, xanthene, nitro, acridone, stilbene,
perinone, naphthoquinone-imine, phthalocyanine, anthraquinone
; and azo dyes. These last mentioned dyes can be metal free,
metallisable or metalliferous monoazo, disazo and polyazo dyes,
" , . , , ~ . .
. 1063944
including formazane dyés, in which the metal atom forms a 1:1
or 1:2 complex, especially 1:2 chromium or 1:2 cobalt complexes
which contain two similar or two different molecules of azo
dye compiexed to a chromium or a cobalt atom. These dyes canalso
contain in the molecule reactive groups, i.e. groups which
form a covalent bond with the fibrous material to be dyed.
The cationic dyes that can be removed from the ef-
fluents with the aid of the polymer gel are as a general
rule the customary salts and metal halides, for example zinc
chloride double salts, of the known cationic dyes the cationic
character of which derives from a carbonium, an oxonium, a
sulphonium and, above all, an ammonium group. Examples of
such chromophoric systems are: methine, azomethine, azo,
hydrazone, azine, oxazine, thiazine, diazine, xanthene,
acridine, polyarylmethane, such as diphenylmethane or tri-
phenylmethane, and also cumarin and azo dyes which contain
an indolinium, pyrazolium, triazolium, tetrazolium, oxadia-
zolium, thiadiazolium, oxazolium, thiazolium, pyridinium,
pyrimidinium or pyrazinium ring. They can also be arylazo,
phthalocyanin and anthraquinone dyes which carry, for example,
an external cycloammonium or alkylammonium group.
The process of this invention is suitable not only
for decolourising residual liquors occurring in the dyestuffs,
textile, fibre, paper, and leather industry, but furthermore
14
.;
', ', ~
1063944
is also most useful when it is a matter of eliminating residues
of anionic O-f cationic fluorescent brighteners from wash and
bleach liquors.
The fluorescent brighteners can belong to any class
of brightener compounds. The anionic brighteners are in
particular stilbene compounds, cumarins, benzocumarins,
pyrazines, pyrazolines, oxazines, dibenzoxazolyl or di-
benzimidazolyl compounds or naphthalic imides which contain
in the molecule at least one acid group, for example a
carboxylic acid or preferably a sulphonic acid group, and
which can be fibre reactive. The cationic brighteners are pri-
marily those of the methine, azomethine, benzofuran, benzi-
midazolyl, cumarin, naphthalimide or pyrazoline class.
The water-insoluble, non-ionic dyes which can also
be removed according to the invention include disperse dyes,
vat dyes, sulphur dyes, water-insoluble fluorescent brighteners
and organic and inorganic pigments.
A further advantage of the adsorption material
according to the invention is that, besides the dyes, it
- 20 permits also a partial elimination of non-ionic, anionic and
cationic surfactants and textile and dyeing assistants from
aqueous waste liquors. Such assistants are described in more
detail in "Tenside-Textilhilfsmittel-Waschrohstoffe" by
Dr. Kurt Lidner (published by Wissenschaftliche Verlagsgesell-
- 15 -
1063944
schaft Stuttgart, 1964).
The adsorption agent can also be effective in the
elimination of anionic synthetic tannins, especially tannins
that carry one or more sulpho groups in the molecule. A more
detailed description of these compounds can be found e.g.
in "Ullmans Encyclop~die der technischen Chemie", Vol. 11,
pp. 595-598.
Appropriate choice of the adsorption material makes
it possible to extract up to 100% of the impurities from the
effluents. Retardant effects of up to 50 g of waste matter,
i.e. dye, fluorescent brightener, assistant, detergent,
tannin, per 100 g of adsorption material can be achieved.
Whenever a complete decolourisation or removal of the waste
substances cannot be accomplished by a single treatment of the
waste liquor with the adsorption material, it is advisable
to repeat the cleansing procedure. The amount of adsorption
material used can be reduced to a minimum by means of a
recirculation.
The treatment according to the invention of the
polluted liquid media with the polymer gels can optionally
also be only part of a purification or recovery process. The
preparation of drinking water and also certain effluent
treatments can be effected over a number of steps in one of
which the cited polymer gels can be used as adsorbent.
- 16 - -
, " .
. ' , - . ~ ~,
,, " .,,, . ., ~ .
1063944
After the adsorption of the impurities, the adsorp-
tion capacity of the polymer gels can be partially or completely
recovered, for example by extraction with suitable ~olvent~,
The invention is illustrated by the following
Examples in which the parts and percentages are by weight,
.
. 17
. . . ..
', ~' ' ' . ` ' " ,
., ' ~ ' ' . ' ~ ' ' ',
,
,, , :
.,
~063944
Example 1
With good stirring, 5 litres of a warm (32C) green
coloured liquor which contains 0.2 g/l of a dye of the formula
~ ~ 3
O.OS g/l of a dye of the formula
N = N ~ N - CH2 ~ 1 C~3S0
C1~3 C1~3
_ " _
0.1 g/i of a dye of the formula
N = N- ~ N = N ~ NH ~ (3)
1 g/l of a dyeing assistant of the formula
- 18 -
,~
10~3944
~ (C~2C~120)XH
C18~22 37-45 ~ (cH2c~l2o)yH
(x ~ y ~ 35)
and 1 g/l of 80% acetic acid, 2 g/l of sodium sulphate
solution and 1.5 g/l of sodium acetate solution, are treated
for 3 minutes with 12 g (referred to the solids content) of
a polymer gel prepared from a polyamide 66 ultra-deep dyeing
type (Du Pont Nylon 848). The polymer gel, which has been
obtained by dissolving the polymer in formic acid and coagulat-
ing the solution in a mixture of water and formic acid (1:1),
has a specific surface area of 165 m~/g, determined by the BET
method. After separation of the adsorber material by filtration,
the liquor is completely decolourised.
Example 2
. .
A polyacrylonitrile cable which has been wet spun
from dimethyl formamide and consists of filaments of 3 denier
individual titre, is cut in the hydrated state and comminuted
to an ~verage length of 1 mm. The material has a specific
surface area of 210 m2/g, determined by the BET me~hod. 5.4 g
of this fibre pulp, which corresponds to 2 g of the dry poly-
acrylonitrile, are stirred at room temperature into 1.5 litresof an aqueous liquor which contains 0.5 g/l of a dye of the
formula
- 19 -
1063944
~ ~ \ C - N ~ ~ ~ ~ - CU2CH 1 ~nC13
'~ C~12CH2 0~ - .
CH3
__
After a contact time of 2 minutes the liquor is separated
from the polyacrylonitrile fibre pulp by filtration. After
this treatment the liquor still contains only 0.1 g/l of the
above dye.
The same result is obtained by carrying out the
treatment of the liquor at 40 or 80C.
Example 3
A glass tube of 20 mm internal diameter is filled
with 75 g of a polyacrylonitrile cable spun from an aqueous
sodium thiocyanate solution. The hydrated piece of cable
corresponds to 30 g of dry fibre material. Its specific
surface area is l9S m2/g, determined by the BET method. An
aqueous liquor of 35C, which contains 5 gll of the blue dye
of formula (5), is then passed through this adsorption column
from underneath. The adsorber column turns blue in colour,
whereas the liquor passing through it is completely decolour-
ised. During the passage of the liquor, the adsorption
capacity of the adsorber is 120% of dye, referred to dry
polyacrylonitrile.
- 20 -
~ , ,,
~o63944
Example 4
One arm of a U-shaped tube is continuously and
uniformly packed with hydrated polyacrylonitrile spinning
cable (specific surface area 125 m2/g). The cable packing is
pushed constantly through the tube and drawn out at the other
arm of the tube. A warm liquor of 50C, which contains 0.12 g/l
of a blue dye of the formula (5), is passed in counter-current
at a contact time of 15 seconds through the adsorption material.
The treated liquor that flows out is completely colourless.
Adsorpt;on capacity of the adsorber: 21% of dye.
Example 5
Four agitator vessels, arranged in the corners of
a square and connected by piping, are each charged with 20
litres of water and lkg of the polyacrylonitrile fibre pulp
described in Example 2. An orange coloured warm dyeworks
effluent of 55C, which contains 0.03 g/l of a dye of the
formula
- Cl -
~ N =N ~ N - CH2 - CH2 - N ~ ¦ Cl ~
and 0.02 g/l of a commercial disperse dye consisting of 42%
1063944
of a dy~ of the formula
01~
C~3CON~1 ~ N =N ~ (7)
CH3
15% of sulphite lye and 43% of a naphthalenesulphonic acid,
is then passed through 3 of the 4 series-connected agitator
vessels. The average dwell time of the liquor is 10 seconds
per agitator vessel. The liquor flows first from vessel I to
II and from there to III and finally into a receiver vessel.
As soon as the liquor no longer emerges colourless from the
third agitator vessel, the fourth one, which contains fresh
adsorption material, is connected to the third, so that the
liquor is again completely decolourised. The adsorption
capacity of the adsorber of vessel I is 33% of dye.
: Example 6
100 litres of a greyish-blueeffluent with a pH o
10.6 and a TOC content of 67 mg/l and with 2.77 g/l of
dissolved solids containing 14 percent by weight of a reactive
dye, are passed at room temperature and a contact time of 20
seconds per unit of weight of adsorption material through a
- cleansing column which is charged with 600 g (referred to the
solids content) of a polymer gel (specific surface area:
165 m2/g) prepared from polyamide 66 of the ultra-deep dyeing
type (Du Pont nylon 848). After it has passed through the
- 22 -
.
, ' ~ . ~ :. ' ' -
, . ,
~o63944
column, the liquor is colourless and has a TOC content ofonly 32 mg/l. TOC = Total organic carbon.
Example 7
100 g of a copolymer of 92% of acrylonitrile and 8%
of vinyl acetate are dissolved in 900 g of dimethyl formamide.
Then 200 g of this polymer solution are added, as a thin jet,
through a hollow needle with an internal diameter of 0.6 mm
to 2 litres of cold water, which is stirred vigorously in an
impeller mixer. A polymer gel with a principal particle size
10 of 0.05 to 0.2 mm is obtained; it is separated from water by
filtration. The polymer gel has a specific surface area of
102 m2/g, determined by the BET method.
3 g of this adsorption material, containing 0.51 g
of dry polyacrylonitrile, are added to 0.5 litres of a liquor
15 of 20C, which contains 0.12 g/l of a blue dye of the formula
(5). After stirring vigorously for 2 minutes and separation
of the adsorber, the liquor still contains only 0.045 g/l of
the dye.
By using the polymer gels listed in column 2 of the
following table instead of the adsorption material used in
this Example, and otherwise carrying out the procedure in
- similar manner as described above, the liquor described in
column 3 can be decolourised at the temperatures indicated in
column 4. Column 5 indicates the decolourising time in minutes,
column 6 the residual dye concentration, and column 7 the
percentage adsorption capacity.
- 23 -
,
'' ' '
:, . .
063944
...... _ ~o
_ _ . . ~ - - o ,,
~o ~ o C~ o o ~
_ , _ ._ .. _ . .. _ s
u~ E ~ ~I O
~ o O O O Il~ C
_ _ ._ - C
~ Cô _ h r
~ E ~ E O
I l a 1 ~ c, V ~
E .~ ~ o ~, v h
_ _
. h ~ h I E
COO ~ ~ QJ~ S ~.
O v O ~ ~ , v
~t S ~ o .~ æ O
W ~0 40 ~0 ~ h O o O ~I h
h h N CO S~ O O O ~ O O h h ~
~1 O Cl` O ~ t-- N ~o o C~ ~ o N CO o, U J--
.. _
_~ ~q CO C~` O ,~ ~ O
. ,
- 24 -
. , .. ;.:.
. . .
.
. ;, . ...
~Ot;3944
_ ~
- N N N
t- ~
_ .__ O ~ ~, ------ __ _,
~O ~ O O O O O
_ __ _~ . .__ _ _
~:
u~ v E N N _I N N
_ _~
~ C~ OU~ O U~
N 1 ~ t-- N ~
;~ ___ __ _
I I
Co' cr~ h
. P~
V ~ ~1 ~ ~ j,
~ ~I S . N
~ a 5 ~ , o V v
~ ~ z~ Z,~ < .
D _ O ~ O
,1 N h O u~ S u~ r~
~ ~ o C~ O ~ fa ~ I
_ . .
O ~ O
O h rl ~ o ~. E ~> ~ o ~ ~ ~
O ~ ~ o ~ o ~ ~ ~d O ~I CO h
C) ~: ~ O ~: O
~ S ~ S ~ ~ '~ " '-I
E h O ~ h O O O o r I o ~
~1 ~ O ~ ~ ~ ~ O rl ~ > rl o
N O` O~ CO ~ N Ul .~
. __ ~ N ~ U~ ~O .
- 25
,.
, ...
1063944
. ___ ,. . ,~
~ ~. ,,~,j . .
l ~__ ~ ~
~ W o o o
~ ~ N ~\1 N
I~ ~ F~
____ _
. ~, 2 __ ~ o
1~ 3 ~ ~
o
~' ~,Y ~L '
~ ~ ~ O O .~ I
N fi ~ rO N ~
`O ' ' ~ U~ ~
~ c5 ~ h ~
a ~ '' ~ v
N O ~ `~ ~ ,o P~
. .,~_1 VJ _ _
.' _~ _. .
'' ' ,
1063944
__ _. _ __ _
~ ~ o o
-- r ,1 ,
__ O . _.. ___ ___ _
:t o ~ ~,
.~ ~ ~ O ~ ~ ~ ~0
- ;~
i !
,, ~ .
- 27
106394~
~ample 22
9 parts of a copolymer of 92% of acrylonitrile and
8% of vinyl acetate are dissolved together with 1 part o
primary octadecyl~rriine in 60 parts of dimethyl acetamide.
300 g of this polymer solution are sprayed with air
from a spray gun under water at room temperature, to give a
fibrous pGlymer gel with an average particle size of 0.02 to
0.15 mm, ~hich is separated by filtration from water or a
mixture of water/dimethyl acetamide, and rinsed with warm
water of 40C. The specific surface area of the polymer gel
is 153 m2/g, determined by the BET method.
5 g of this adsorption material, containing 1.6 g
of the dry copolymer, are added to 1 litre of a liquor of 25C,
which contains 0.5 g of the blue direct dye of the formula
Y,O S ~--Cu-- O O-- Cu-- O
H- ~ 0
S03H 3
After sti.rring vigorously for 5 minutes and separating off
the adsorber, the liquor stili contains only 0.06 g/l of dye.
The adsorber has an adsorption capaci.ty of 27.5% of dye,
referred to the dry adsorption material.
- 28 -
' ' , '
:, , .
, . , '' ' ` ' ` ' .
1063944
Exarnple 23
300 g of thc polymer solution of Exarnple 22 are
atomised at room temperature with aiL' from a spray gun. The
spray is directed at an acute angle towa.ds the spray from a
second spray gun from which water of room temperature is
atomised. ~hen both sprays come in contact, the polymer co-
agulates in very fine, amorphous form. The coagulate is
collected in a glass tube, rinsed with warm water of 40C and
filtered off, to yield a polyrner gel wi~h an average particle
size of 0.01 go 0.1 mm. The specific surface area of the
polymer gel is 185 m /g, determined by the BET method. In
the same decolourising liquor as described in Example 22, a
liquor is obtainedwhich still contains on].y traces of dye.
The adsorption capacity of the adsorber is 31.3% of dye,
referred to the dry adsorption material.
A similar result is obtained by atomising the
polymer solution in contact with steam instead of a water
spray.
,. .
- 29 -
" . .
. . ,, ,. ~ .
.
'.'
