DE102006034668A1 - Medium or strong base anion exchangers - Google Patents

Abstract

The present application relates to novel monodisperse or heterodisperse, gelatinous or macroporous, moderately or strongly basic anion exchangers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound which has both carboxyl groups COOR <SUB> 3 </ SUB> and - (CH <SUB> 2 </ SUB>) <SUB> m </ SUB> NR <SUB> 1 </ SUB> R <SUB> 2 </ SUB> and / or - (CH <SUB> 2 </ SUB>) <SUB> m </ SUB> NR <SUB> 1 </ SUB> R <SUB> 2 </ SUB> R <SUB> 4 </ SUB> groups, a process for their preparation and their use, in particular the use of monodisperse anion exchangers in hydrometallurgy.

Description

The present application relates to novel monodisperse or heterodisperse, gel or macroporous, medium or strong base anion exchangers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups, a process for their preparation and their use, in particular the use of monodisperse anion exchangers in hydrometallurgy.

For a variety separation problems in the art are already anion exchangers today used. So they are used among other things for the removal of anions from aqueous or organic solutions, to remove anions from condensates, to remove color particles from aqueous or organic solutions or for removal of organic components from aqueous Solutions, for example of humic acids from surface water.

Farther can Anion exchanger for the purification and treatment of waters in the chemical industry and electronics industry, in particular for Production of ultrapure water or in combination with gel and / or macroporous Cation exchangers for demineralization of aqueous solutions and / or condensates be used.

About these would like to know well-known applications you new application areas for Open up anion exchangers, for the currently known anion exchangers are not suitable or no sufficient adsorption capacity demonstrate.

It There is therefore a need for new anion exchangers based on at least one monovinylaromatic compound, preferably styrene, and at least one polyvinyl aromatic compound having an improved Exchange kinetics and selectivity for ions to be separated show as well as a high mechanical and osmotic stability, in column methods a lower pressure loss, no abrasion, as well as a clear lower pressure loss than the ion exchangers according to the state of the technique.

The Object of the present invention is now, anion exchange resins with the above-described requirement profile for the removal of substances, preferably polyvalent anions, from liquids, preferably aqueous Provide media or gases, as well as the provision of a Process for their preparation. To substances within the meaning of the present Counting invention also precious metals.

The solution and thus the subject of the present invention are novel monodisperse or heterodisperse, gel or macroporous, medium or strong base anion exchangers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups in which
R _{1 is} C ₁ -C ₄ -alkyl, preferably CH ₃ , or is a hydroxyalkyl group with C ₁ -C ₄ -alkyl,
R _{2 is} C ₁ -C ₄ -alkyl, preferably CH ₃ or a hydroxyalkyl group with C ₁ -C ₄ -alkyl,
R _{3 is} H and / or Na and / or K,
R _{4 is} C ₁ -C ₄ -alkyl, preferably CH ₃ , or is a hydroxyalkyl group with C ₁ -C ₄ -alkyl and
m is an integer from 1 to 4.

These novel anion exchangers are obtained starting from bead polymers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound acting as crosslinker with additional (C ₁ -C ₄ -alkyl) acrylic compounds.

Surprisingly These new anion exchangers show improved yields their production, in the case of macroporous anion exchangers larger pores and smaller specific surface and better kinetics than anion exchangers when used, as known from the prior art.

• a) Monomertröpfchen aus einem Gemisch einer monovinylaromatischen Verbindung, einer polyvinylaromatischen Verbindung, einer (C₁-C₄-Alkyl)acrylverbindung, gegebenenfalls einem Initiator oder einer Initiator-Kombination, sowie gegebenenfalls einem Porogen zu einem vernetzten Perlpolymerisat umsetzt,
• b) das erhaltene Perlpolymerisat aus a) mit schwachbasischen anionenaustauschenden Aminomethylgruppen Gruppen funktionalisiert und in diesem Schritt, der eine Behandlung mit wässrigen Verseifungsmitteln, bevorzugt eine natronalkalische Behandlung, einschließt, die copolymerisierten (C₁-C₄-Alkyl)acrylverbindungen zu (C₁-C₄-Alkyl)acrylsäuregruppen mit dem COOR₃-Rest umsetzt.
• c) das erhaltene Perlpolymerisat aus b), das nun schwachbasische anionenaustauschende Aminomethylgruppen enthält, zu Perlpolymerisaten mit mittel- und/oder starkbasischen anionenaustauschenden Gruppen mit zusätzlichen Carboxylgruppen COOR₃ umsetzt.

However, the present invention also relates to a process for preparing the novel, monodisperse or heterodisperse, gel or macroporous anion exchangers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups in which
R _{1 is} C ₁ -C ₄ -alkyl, preferably CH ₃ , or is a hydroxyalkyl group with C ₁ -C ₄ -alkyl,
R _{2 is} C ₁ -C ₄ -alkyl, preferably CH ₃ , or is a hydroxyalkyl group with C ₁ -C ₄ -alkyl,
R _{3 is} H and / or Na and / or K,
R _{4 is} C ₁ -C ₄ -alkyl, preferably CH ₃ , or is a hydroxyalkyl group with C ₁ -C ₄ -alkyl and
m is an integer 1, 2, 3, or 4,
characterized in that one

• a) monomer droplets from a mixture of a monovinylaromatic compound, a polyvinylaromatic compound, a (C ₁ -C ₄ alkyl) acrylic compound, optionally an initiator or an initiator combination, and optionally a porogen to give a crosslinked bead polymer,
• b) the resulting bead polymer from a) is functionalized with weakly basic anion-exchanging aminomethyl groups and, in this step, which includes a treatment with aqueous saponification agents, preferably a sodium-alkaline treatment, the copolymerized (C ₁ -C ₄ alkyl) acrylic compounds to (C ₁ - C ₄ alkyl) acrylic acid groups with the COOR ₃ radical.
• c) the resulting bead polymer from b), which now contains weakly basic anion-exchanging aminomethyl groups, is converted to bead polymers having medium- and / or strongly basic anion-exchanging groups with additional carboxyl groups COOR ₃ .

As hydroxyalkyl groups in the radicals R ₁ , R ₂ and R ₄ are -CH ₂ OH, -CH ₂ CH ₂ OH, -CH ₂ CH ₂ CH ₂ OH, -CH ₂ CH (CH ₂ ) OH, -CH ₂ CH ( OH) CH ₃ , -CH ₂ CH ₂ CH ₂ CH ₂ OH, -CH ₂ CH ₂ CH (OH) CH ₃ , -CH ₂ CH (CH ₂ OH) CH ₃ , -C (CH ₂ OH) (CH ₃ ) ₂ , and -CHOHCH ₂ CH ₂ CH _{3 is} preferred.

worin
x = 0,01-0,3
y = 0,7-0,99
z = 0,01-0,2
A für H oder C₁-C₄-Alkyl, bevorzugt CH₃, steht
m für eine ganze Zahl 1, 2, 3, oder 4 steht
R₁ für C₁-C₄-Alkyl, bevorzugt CH₃, oder für eine Hydroxyalkylgruppe mit C₁-C₄-Alkyl steht,
R₂ für C₁-C₄-Alkyl, bevorzugt CH₃, oder für eine Hydroxyalkylgruppe mit C₁-C₄-Alkyl 4 steht,
R₃ für H und/oder Na und/oder K steht und
R₄ für C₁-C₄-Alkyl, bevorzugt CH₃, oder für eine Hydroxyalkylgruppe mit C₁-C₄-Alkyl steht,
wobei mit

in Formel (I) das Polymergerüst, bevorzugt aus Styrol- und Divinylbenzol-Einheiten, angedeutet ist.In a preferred embodiment, the present invention relates to monodisperse or heterodisperse, gel or macroporous, medium or strong base anion exchangers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups of the general formula (I) which form during process step b)

wherein
x = 0.01-0.3
y = 0.7-0.99
z = 0.01-0.2
A is H or C ₁ -C ₄ -alkyl, preferably CH ₃
m stands for an integer 1, 2, 3, or 4
R _{1 is} C ₁ -C ₄ -alkyl, preferably CH ₃ , or is a hydroxyalkyl group with C ₁ -C ₄ -alkyl,
R _{2 is} C ₁ -C ₄ -alkyl, preferably CH ₃ , or is a hydroxyalkyl group with C ₁ -C ₄ -alkyl 4,
R _{3 is} H and / or Na and / or K and
R _{4 is} C ₁ -C ₄ -alkyl, preferably CH ₃ , or is a hydroxyalkyl group with C ₁ -C ₄ -alkyl,
being with

in formula (I) the polymer backbone, preferably from styrene and divinylbenzene units, is indicated.

In a particularly preferred embodiment, the present invention relates to monodisperse Form of the new anion exchanger.

In order to obtain macroporous, ie large-pore, anion exchangers, the anion exchangers according to the invention are based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound which has both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ groups and / or - ( CH ₂ ) _m NR ₁ R ₂ R ₄ , preferably prepared from bead polymers using porogen.

The monodisperse, crosslinked, vinylaromatic base polymer used on the basis of a monovinylaromatic component and a polyvinylaromatic compound which acts as a crosslinker with additionally (C ₁ -C ₄ -alkyl) acrylic compounds is disclosed in US Pat WO 2005/049190 described.

In its preparation - process step a) - at least one monovinylaromatic compound, at least one polyvinylaromatic compound and at least one (C ₁ -C ₄ alkyl) acrylic compound is used. However, it is also possible to use mixtures of two or more monovinylaromatic compounds and mixtures of two or more polyvinylaromatic compounds.

(C ₁ -C ₄ -alkyl) acrylic compounds which are preferred for use in accordance with the invention are monoethylenically unsaturated compounds, such as alkyl (meth) acrylates, (meth) acrylonitriles, (meth) acrylic acid. Particularly preferred according to the invention are methyl acrylate, methyl methacrylate and acrylonitrile. For the purposes of the present invention, particular preference is given to using acrylonitrile or methyl acrylate.

The (C ₁ -C ₄ -alkyl) acrylic compounds are generally used in amounts of from 1 to 30% by weight, preferably from 1 to 10% by weight, based on the sum of all monomers.

When Monovinylaromatic compounds in the context of the present invention in process step a) are preferably monoethylenically unsaturated compounds, particularly preferably styrene, vinyltoluene, ethylstyrene, α-methylstyrene, Chlorstyrene, chloromethylstyrene, alkyl acrylate or alkyl methacrylate used. Very particular preference is given to styrene or mixtures of styrene used with the aforementioned monomers.

According to the invention as a crosslinker Polyvinylaromatic compounds to be used are multifunctional ethylenically unsaturated Compounds such as preferably divinylbenzene, divinyltoluene, trivinylbenzene, Divinylnaphthalene, trivinylnaphthalene, 1,7-octadiene, 1,5-hexadiene, Ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate or Allyl methacrylate. Particularly according to the invention Divinylbenzene is preferably used.

The Polyvinyl aromatic compounds are generally used in quantities from 1-20% by weight, preferably 2-12% by weight, more preferably 4-10 Wt .-%, based on the monovinyl aromatic compound (hereinafter also referred to as monomer) or their / their mixture with others Monomers used. The nature of the polyvinyl aromatic compounds will be with regard to the later Use of the spherical Polymer selected. Divinylbenzene is therefore particularly preferred, including commercial ones for most applications divinylbenzene which in addition to the isomers of divinylbenzene also ethylvinylbenzene contain, suffice.

In a preferred embodiment In the present invention, microencapsulated monomer droplets are used Commitment.

For microencapsulation the monomer droplets come for the the use as Komplexkoazervate known materials in question, especially polyester, natural or synthetic polyamides, polyurethanes or polyureas.

As a natural polyamide, for example, gelatin is particularly well suited. This is used in particular as coacervate and complex coacervate. Gelatin-containing complex coacervates in the context of the present invention are understood to mean, in particular, combinations of gelatin with synthetic polyelectrolytes. Suitable synthetic polyelectrolytes are copolymers with incorporated units of maleic acid, acrylic acid, methacrylic acid, acrylamide and methacrylamide. Particular preference is given to using acrylic acid and acrylamide. Gelatin-containing capsules can be cured with conventional curing agents such as formaldehyde or glutardialdehyde. The encapsulation of monomer droplets with gelatin, gelatin - containing coacervates and gelatin - containing complex coacervates is reported in the EP-A 0 046 535 described in detail. The methods of encapsulation with synthetic polymers are known. Well suited, for example, is the interfacial condensation, in which a Re dissolved in the monomer droplets active component (for example an isocyanate or an acid chloride) is reacted with a second reactive component dissolved in the aqueous phase (for example an amine).

The optionally microencapsulated monomer droplets optionally an initiator or mixtures of initiators for triggering the Polymerization. In this case suitable initiators are, for example Peroxy compounds such as dibenzoyl peroxide, dilauroyl peroxide, bis (p-chlorobenzoyl) peroxide, Dicyclohexyl peroxydicarbonate, tert-butyl peroctoate, tert-butyl peroxy-2-ethylhexanoate, 2,5-bis (2-ethylhexanoylperoxy) -2,5-dimethylhexane or tert-amylperoxy-2-ethylhexane, and azo compounds such as 2,2'-azobis (isobutyronitrile) or 2,2'-azobis (2-methylisobutyronitrile). In the case of using initiators these are generally in amounts of from 0.05 to 2.5% by weight, preferably 0.1 to 1.5% by weight, based on the monomer mixture, applied.

Of the Initiator is added only in the microencapsulation.

As further additives in the optionally microencapsulated monomer droplets, porogens can be used, in particular in order to produce a macroporous structure and thus large-pore anion exchangers in the spherical polymer. Without the use of porogen, gel-type anion exchangers are obtained. The terms macroporous or gel have already been described in detail in the literature. Suitable porogens are above all organic substances which dissolve in the monomer but dissolve or swell the polymer poorly (precipitants for polymers), for example aliphatic hydrocarbons (Farbenfabriken Bayer DBP 1045102, 1957, DBP 1113570, 1957). In order to produce macroporous anion exchangers according to the invention, preference is therefore given to using hexane, octane, isooctane, isododecane, methyl ethyl ketone, butanol or octanol or isomers thereof. Alternatively, however, it is also possible to use alcohols having 4 to 10 carbon atoms as porogen for the preparation of the monodisperse, macroporous styrene / divinylbenzene-based bead polymers, as in US Pat US Pat. No. 4,382,124 described. There is also given an overview of the production methods of macroporous bead polymers.

The optionally microencapsulated monomer droplets may optionally also up to 30 wt .-% (based on the monomer) of crosslinked or contain uncrosslinked polymer. Preferred polymers are derived from the abovementioned monomers, particularly preferably from styrene, from.

When Monodisperse in the present application refers to such substances, where at least 90% or mass% of the particles have a Have diameter in the interval with the width of ± 10% of common Diameter around the most common Diameter lies around.

For example, for a fabric with the most common diameter of 0.5 mm, at least 90% by volume or mass% is between 0.45 mm and 0.55 mm in a size interval, and at least 90 with a most common diameter material of 0.7 mm Volume or mass% in a size interval between 0.7 mm and 0.63 mm. In addition to the fractionation of heterodisperse ion exchangers by sieving, a distinction is essentially made between two direct production processes, namely atomization or jetting and the seed-feed process. Both variants are used according to the invention for the preparation of the precursor of the anion exchanger, namely for the synthesis of the bead polymers, before they are functionalized. In the case of the seed-feed method, it is also possible to use a monodisperse feed, which in turn has been previously produced by sieving or jetting. Reference is made to this point US Pat. No. 4,444,961 . EP-A 0 046 535 . US-A 4,419,245 and WO 93/12167 , For the synthesis of the heterodisperse form of the anion exchanger according to the invention be on US Pat. No. 4,077,918 and US Pat. No. 4,952,608 directed.

The mean pond size of monodisperse, optionally microencapsulated monomer droplets is 10-1000 microns, preferably 100-1000 microns.

In the preparation of the bead polymers according to process step a), the aqueous phase may optionally contain a dissolved polymerization inhibitor. Suitable inhibitors for the purposes of the present invention are both inorganic and organic substances. Examples of inorganic inhibitors are nitrogen compounds such as hydroxylamine, hydrazine, sodium nitrite and potassium nitrite, salts of phosphorous acid such as sodium hydrogen phosphite and sulfur-containing compounds such as sodium dithionite, sodium thiosulfate, sodium sulfite, sodium bisulfite, sodium thiocyanate and ammonium thiocyanate. Examples of organic inhibitors are phenolic compounds such as hydroquinone, hydroquinone monomethyl ether, resorcinol, pyrocatechol, tert-butylpyrocatechol, pyrogallol and condensation products of phenols with aldehydes. Other suitable organic inhibitors are nitrogen-containing compounds. These include hydroxylamine derivatives such as N, N-diethylhydroxylamine, N-isopropylhydroxylamine and sulfonated or carboxylated N-alkylhydroxylamine or N, N-dialkylhydroxylamine derivatives, hydrazine derivatives such as N, N-hydrazinodiacetic acid, nitroso compounds such as N-nitrosophenylhydroxylamine, N-nitrosophenylhydroxylamine ammonium salt or N-nitrosophenylhydroxylamine aluminum salt. The concentration of the inhibitor in such cases is 5-1000 ppm (based on the aqueous phase), preferably 10-500 ppm, more preferably 10-250 ppm.

The polymerization of the optionally microencapsulated monomer droplets to give the spherical, bead polymer takes place, as already mentioned above, if appropriate in the presence of one or more protective colloids in the aqueous phase. Suitable protective colloids are natural or synthetic water-soluble polymers, such as, for example, gelatin, starch, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, polymethacrylic acid or copolymers of (C ₁ -C ₄ -alkyl) acrylic acid and (C ₁ -C ₄ -alkyl) acrylic esters. Preferred variants of the (C ₁ -C ₄ alkyl) acrylic acid and (C ₁ -C ₄ alkyl) acrylic acid esters are the (met) acrylic esters and the (met) acrylic acid. Also very suitable are cellulose derivatives, in particular cellulose esters and cellulose ethers, such as carboxymethylcellulose, methylhydroxyethylcellulose, methylhydroxypropylcellulose and hydroxyethylcellulose. Particularly suitable is gelatin. The amount used of the protective colloids in such cases is generally 0.05 to 1 wt .-% based on the aqueous phase, preferably 0.05 to 0.5 wt .-%.

The Polymerization to spherical Bead polymer may optionally also in the presence of a buffer system carried out become. Preference is given to buffer systems which increase the pH of the aqueous phase at the beginning of the polymerization to a value between 14 and 6, preferably set between 12 and 8. In these conditions Protective colloids with carboxylic acid groups are all or part as salts. In this way, the effect of protective colloids Cheap affected. Particularly suitable buffer systems contain phosphate or borate salts. The terms phosphate and borate within the meaning of the invention also include the condensation products of the ortho-forms corresponding acids and salts. The concentration of phosphate or borate in the aqueous Phase is in such cases 0.5-500 mmol / l, preferably 2.5-100 mmol / l.

The Stirring speed in the polymerization is less critical and has in contrast to the conventional Bead polymerization does not affect the particle size. It will low stirring speeds applied, which are sufficient, the suspended monomer droplets in Hold the levitation and the exhaustion the heat of polymerization to support. For this Task can different types of stirrers be used. Particularly suitable are lattice stirrer with axial effect.

The volume ratio of encapsulated monomer droplets too watery Phase is 1: 0.75 to 1:20, preferably 1: 1 to 1: 6.

The Polymerization temperature depends on the decomposition temperature of the initiator used. It is generally between 50 up to 180 ° C, preferably between 55 and 130 ° C. The polymerization lasts 0.5 hours to a few hours. It has proven, to use a temperature program in which the polymerization at low temperature, for example 60 ° C is started and the reaction temperature is increased with increasing polymerization conversion. On that way For example, the demand for safe reaction and fulfill very high polymerization conversion. After the polymerization is the polymer with conventional Methods, for example by filtration or decantation, isolated and optionally washed.

The functionalization of the crosslinked bead polymers from process step a) in the subsequent process step b) can be carried out by various processes. EP-A 0 046 535 and EP-A 107 86 88 describe the preparation of monodisperse, gel and macroporous medium or strong base anion exchangers by functionalization of crosslinked styrene-divinylbenzene-based bead polymers by the phthalimide method. In this case, the bead polymers are substituted with phthalimide derivatives. This is followed by treatment of the bead polymers substituted with phthalimide derivatives with aqueous saponification agents, preferably with sodium hydroxide solution. In this case, the production of the aminomethylated bead polymer takes place. The treatment with aqueous saponification agents, preferably with sodium hydroxide solution, simultaneously converts the (C ₁ -C ₄ -alkyl) acrylic compounds into COOR ₃ groups as functional groups. Heterodisperse bead polymers are functionalized according to the invention by the same methods as monodisperse bead polymers.

However, the functionalization of said monodisperse bead polymers according to process step b) can also be carried out by other processes. For example, an anion exchanger can be obtained by chloromethylation and subsequent reaction with amines. In US Pat. No. 4,444,961 or in EP-A 0 051 210 Several methods for the preparation of anion exchangers are cited by functionalization of crosslinked bead polymers based on styrene-divinylbenzene after Chlormethylierungsverfahren. In principle, this process can also be applied to the bead polymers based on monovinylaromatic compounds and polyvinylaromatic compounds with carboxyl groups which can be used in the present process.

The Methods of said prior art are in the present Method used in step b), preferably the phthalimide method.

The conversion of the weakly basic Anionenaustasucher produced as a result of process step b) to medium and / or strong base anion exchangers in process step c) can according to the aforementioned methods in EP-A 0 046 535 . EP-A 1 078 688 . US Pat. No. 4,444,961 or EP-A 0 051 210 respectively.

In process step c), the monodisperse or heterodisperse, gel or macroporous, medium or strongly basic anion exchanger according to the invention is prepared on the basis of at least one monovinylaromatic compound and at least one polyvinylaromatic compound which has both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups, by reaction of the aminomethylene-containing monodisperse, crosslinked, vinylaromatic polymer from process step b) in suspension with alkylating agents.

preferred Alkylating agents in the context of the present invention are alkyl halides, Halo alcohols, alkyl sulfates, dialkyl sulfates, alkyloxides, Leuckart-Wallach reagents or combinations of these alkylating agents with each other or successively.

Particular preference is given to using chloromethane, ethylene oxide, propylene oxide and the Leuckert-Wallach reagents or their combination. Exemplary are Leuckart Wallach reagents in Organikum, VEB German publishing house of the sciences, Berlin 1968, 8th edition, page 479 described.

When Suspension medium, water or mineral acids are used. Possibly but can also in dependence of the desired Product bases are added. Preferably, water is used. The bases used are preferably sodium hydroxide solution, potassium hydroxide solution or basic, but not nucleophilic amines in question.

Of the Process step c) is preferred at temperatures of 20 to 150 ° C, especially preferably carried out at temperatures of 40 to 110 ° C. Process step c) is preferred by pressing from atmospheric pressure to 6 bar, particularly preferably at atmospheric pressure to 4 bar performed.

The monodisperse or heterodisperse, gelatinous and macroporous medium- or strongly basic anion exchangers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound which have both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups are suitable for a variety of separation problems in the art. They can be used to remove anions from aqueous or organic solutions, to remove anions from condensates, to remove paint particles from aqueous or organic solutions, to remove organic components from aqueous solutions, such as humic acids from surface water, for the purification and treatment of water in the chemical industry and electronics industry, in particular for the production of ultrapure water or in combination with gelatinous and / or macroporous cation exchangers for the demineralization of aqueous solutions and / or condensates.

The typical use for the removal of anions from aqueous solutions occurs in the recovery of valuable metals. In numerous processes, the valuable rocks containing iron, cobalt, nickel, manganese, lead, zinc, manganese, zinc, cadmium, uranium, copper, gold or silver are first ground into small particles. From these rock particles, the recyclables can be removed by several methods. The common technique is hydrometallurgy, also known as wet metallurgy. With the help of acids or alkalis, optionally after a pretreatment of the ores to produce soluble compounds (roasting, pyrogenic digestion), the compounds are converted into soluble metal salt solutions. The choice of the solvent is determined by the type of metal, its binding present in the ore, the type of ore companion (gait) and the price. The most widely used solvent is sulfuric acid, besides hydrochloric acid, nitric acid, hot concentrated saline or aqueous saline. For ores with acid-soluble impurities, such as copper, can also ammoniacal solutions are used, sometimes even at high pressure and elevated temperature (pressure leaching). Sodium hydroxide is used for the extraction of alumina, for precious metals alkali cyanide solutions are used. In US 6,350,420 For example, the treatment of the ore particles with mineral acids such as sulfuric acid at high temperatures (eg 250-270 ° C) under pressure (high pressure leaching) is described. This gives a suspension (slurry) of the fine ore particles in sulfuric acid, wherein the dissolved out metals are contained in the form of their salts in more or less concentrated form.

The Recovery of pure valuable substances from these suspensions requires numerous other process steps. These include the separation of the rock particles by decanter or filtration and the separation of the liquid mixture of useful substances, for example about liquid / liquid extractions, into the individual components. The size of these procedures milled ore particles to be used is in the range of about 30 - about 250 microns. Because of The small size of the particles and the large amount of rock is one classical filtration of the particles from the liquid phase to the suction very expensive. Technically applied is usually a separation according to the gravitational principle in decanters by settling the solid Phase in very big Mixer vessels. Around a good separation with a possible particle-free recyclable solution to be stirred with a diameter of 50 meters and more used and several of them in Series. Size Quantities of water are needed which are very expensive, as many mines are located in arid areas (deserts). In addition, must For better separation of the particles often filtration media, the expensive and environment-stressing, are used.

In so-called "Resin in Pulp" (RIP) processes, the slurry is added to ion exchangers which absorb the valuable substances present in the liquid CA Fleming, Recovery of Gold by Resin at the Golden Jubilee Mine, Precious Metals 89, edited by MCJha and SD Hill, TMS, Warrendale, Pa., 1988, 105-119 and in CA Fleming, Resin in pule as an alternative process for cyanide leach slurries, Proceedings of 23 Canadian Mineral Processors conference, Ottawa, January 1991 , described.

In recent years, another method for extracting valuable materials from rock has been developed. Here is dispensed with the crushing of the ore particles. In this so-called "in-situ leach" process, the leach liquor, eg sulfuric acid, is pumped in pipes into the soil to the valuable rock layer, where it releases the valuable substances, thus producing uranium as UO ₂ (SO ₄ ) ₂ . Sulphate complex released from the rock and pumped to the surface of the earth.When aqueous soda solution is used to dissolve the uranium, UO ₂ (CO ₃ ) ₂ carbonatocomplex is formed which is pumped to the surface of the earth.

The valuable liquid containing rock particles is pumped to the surface and worked up there. For larger amounts of rock particles they must be removed by clarification from the liquid. The uranyl anion-containing liquids are pumped through column-mounted anion exchangers and absorbed by them via ion exchange - see Nuclear Issues Briefing Paper 40, June 2003 at -www.uic.com.au/nip40.htm ,

Desirable would be up to dispense with the expensive process step of clarification and the particle laden liquid directly to process further. This would then happen in the way that the liquid over installed in columns Anion exchanger beads are pumped, which absorb the anions. But the anion exchange beads should be so big that their action by the rock particles does not hinder becomes. The rock particles should bead on the anion exchanger beads passing through those in the bottom of the pillars drain out slots can, while the anion exchange beads remain in the column. Are the anion exchange beads similar in size to the Rock particles, so they clog easily and show a limited capacity for the removing anions.

A complete Separation of the fine rock particles is very expensive. Therefore Also ion exchangers are required, which contain a certain amount of rock particles tolerate. Therefor Ion exchange beads are needed with a bead diameter significantly larger than the rock particles, with accelerated kinetics and high stability.

Especially in hydrometallurgical plants and mines filtration and clarification processes represent a high proportion of the capital costs of the plant and the current operating costs, which is why great efforts are made to replace the mentioned expensive process steps with other less capital intensive processes such as the RIP process and the in situ leach method. In the context of the present invention it has been found that in particular the new monodisperse, gel or macroporous anion exchanger based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups are suitable for use in hydrometallurgy. Particularly preferably, the macropose form is suitable.

The present invention therefore also preferably relates to processes for recovering valuable metals from hydrometallurgy processes, preferably in RIP processes or in in-situ leach processes or for working up water containing valuable metal, characterized in that monodisperse, gel or macroporous anion exchangers based on at least one monovinylaromatic compound and at least a polyvinyl aromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups are used.

Compared with the anion exchangers used in the prior art, the monodisperse, gel or macroporous anion exchangers according to the invention surprisingly show better kinetics in the uptake of valuable metals, in particular for iron, cobalt, nickel, manganese, lead, zinc, manganese, cadmium, uranium, copper, Gold or silver, a lower pressure drop and more favorable filtration behavior. The metals mentioned are adsorbed in the form of their anions on the anion exchanger according to the invention. According to the invention to be adsorbed anions are Au (CN) ₂ ^-, Au (Cl) ₂ ^-, Co (CN) ₄ ^4-, Ni (CN) ₆ ^2-, NiCl ₄ ^2-, ₄ MnCl ^2, UO ₂ (SO ₄ ) ^2- , Cu (CN) ₂ ^- , Ag (CN) ₂ ^- .

In a particularly preferred embodiment serve the invention to be used monodisperse, macroporous Anion exchanger for the adsorption of uranium from aqueous solutions in it by acids or aqueous soda leached and where it is then as uranyl ion complex, particularly preferred as uranyl chloride, uranyl phosphate, uranyl acetate, uranyl carbonate, Uranyl sulfate or uranyl nitrate, particularly preferably as uranyl sulfate available by leaching the uranium-containing rock with sulfuric acid, is present. Apart from uranyl sulfate, the inventively used monodisperse anion exchanger also for the adsorption of those uranyl ions, in which the uranium by the respective leaching agent in anionic Form, that is, in the forms mentioned in this section.

In In a very particularly preferred embodiment, the monodisperse substances to be used according to the invention serve macroporous Anion exchanger for adsorbing uranium from aqueous solutions in R.I.P. processes or in-situ leach processes.

Test Methods

Usable capacity of strong basic and medium basic anion exchangers

1000 ml of anion exchanger in the chloride form, i. the nitrogen atom carries as Counterion chloride, are filled in a glass column. 2500 ml of 4% strength by weight sodium hydroxide solution be over the resin is filtered in 1 hour. Then degas with 2 liters, i.e. washed with decationized water. Then it is about that Resin at a rate of 10 liters per hour of water with a total anion hardness of 25 degrees German hardness filtered. In the eluate become the hardness and the residual amount of silica analyzed. At a residual silica content of ≥ 0.1 mg / l the loading is finished.

Out the amount of water that is over the resin is filtered, the total anions hardness of the over-filtered water as well The amount of built-in resin is determined how many grams of CaO per Liters of resin are added. The gram quantity of CaO represents the usable capacity of the resin in the unit of grams of CaO per liter of anion exchanger represents.

Determination of spring water content

Approximately 100 ml of the anion exchanger to be examined are in a Beaker with as much demineralized water (VE = demineralized) poured over, that the resin is covered 1 cm. With a glass rod becomes the expulsion stirred by air bubbles and left to rest for 16 hours, covered with a watch glass. After that you pour over one Glass frit the water off and sucks with vacuum shortly after that in the Resin no standing water layer is more detectable. That so prepared resin is sealed until completion of the determination Stored vessel.

Two approximately 50 ml samples are placed in 2 frit tubes and in the laboratory centrifuge for 5 minutes by centrifugation at a radial acceleration of 11,000 m / sec ² corresponding to 3200 U / min of anhaf freeing the water. The upper 0.6 to 1 cm thick resin layer is discarded.

Out Approximately 40-50 g of the sample is weighed to 1 mg on the fritted tubes (= m1).

• Trocknung: bei 105°C mit leichter Belüftung oder Vakuumtrockenschrank bei 55-60°C (min. 12 Stunden).
• Quellwassergehalt: QW, [QW] = %

This defined portion of resin is quantitatively rinsed in a tared Petri dish, freed by suction from the main amount of water and dried overnight to constant mass (= m2).

• Drying: at 105 ° C with light ventilation or vacuum drying oven at 55-60 ° C (12 hours minimum).
• Source water content: QW, [QW] =%

stability tests

Number of perfect beads after production

100 Beads are viewed under the microscope. The determined is the Number of beads that crack or show chipping. The number of perfect pearls results from the difference of the number damaged Pearls to 100.

Determination of the stability of the resin after the rolling test

The to be tested Polymer is in uniform layer thickness between two plastic towels distributed. The towels are placed on a firm, horizontally mounted pad and subjected to 20 cycles in a rolling apparatus. A work cycle consists of a back and forth conducted Rolling. After rolling, representative samples are made of 100 beads by counting the number of undamaged beads was determined under the microscope.

Swelling

In a column 25 ml of anion exchanger are charged in the chloride form. Successively are 4 wt .-% aqueous Sodium hydroxide, demineralized water, 6 wt .-% hydrochloric acid and again fully desalted water added to the column, the sodium hydroxide solution and the hydrochloric acid from above through the resin and flow the fine water is pumped through the resin from below. The treatment is timed via a control unit. A work cycle lasts 1h. 20 working cycles are carried out. To At the end of the working cycles 100 beads are counted by the resin pattern. determined will be the number of perfect pearls that are not through cracks or Chipping damaged are.

Syringe stability test

For the measurement be first Measured 30 ml of resin and washed with deionised water into the glass cylinder and the cylinder filled to the top with water. In The glass cylinder is a stamp that pressed 1000 times and is relaxed.

To finished exam the number of whole beads are counted under the microscope and in % specified.

Volume play chloride / OH form

100 ml basic groups carrying anion exchanger are used with deionized water rinsed in a glass column. It will 1000 ml of 3% strength by weight hydrochloric acid are filtered in over 1 hour and 40 minutes. Subsequently the resin is washed free of chloride with deionized water. The resin will rinsed in a tamping volumeter under demineralized water and to the volume constancy shaken - volume V1 of the resin in the chloride form.

• Berechnung: V1 – V2 = V3
• V3:V1/100 = Quellungsspiel Chlorid/OH-Form in %

The resin is again transferred to the column. 1000 ml of 2% strength by weight sodium hydroxide solution are filtered through. Subsequently, the resin is washed alkali-free with deionized water to a pH value of 8 in the eluate. The resin is rinsed in a tamping volumeter under demineralized water and shaken to volume constancy - volume V2 of the resin in the free base form - (OH-form).

• Calculation: V1 - V2 = V3
• V3: V1 / 100 = Swelling game chloride / OH-form in%

Determination of the amount of weak and strong basic groups in anion exchangers

100 ml of anion exchangers are placed in a glass column in 1 hour and 40 minutes applied with 1 000 ml of 2 wt .-% sodium hydroxide solution. Subsequently, will the resin with demineralized water to remove the excess of caustic soda washed.

Determination of the NaCl number

• Verbrauchte ml 0,1 n Salzsäure × 4/100 = NaCl-Zahl in mol/Liter Harz.

50 ml of the free base form and washed neutral exchanger are placed in a column and charged with 950 ml of 2.5 wt .-% aqueous sodium chloride solution. The effluent is collected, made up to 1 liter with deionised water and of this 50 ml are titrated with 0.1 N hydrochloric acid. The resin is washed with deionised water.

• Spent ml of 0.1N hydrochloric acid × 4/100 = NaCl number in moles / liter of resin.

Determination of the NaNO ₃ number

• Verbrauchte ml Hg (NO₃)-Lösung × Faktor/17,75 = NaNO₃-Zahl in mol/Liter Harz.

Then 950 ml 2.5 wt .-% sodium nitrate solution are filtered through. The procedure is made up to 1 000 ml with deionised water. From this, an aliquot - 10 ml - is taken and analyzed for chloride content by titration with mercuric nitrate solution.

• Spent ml of Hg (NO ₃ ) solution × factor / 17.75 = NaNO ₃ number in moles / liter of resin.

Determination of the HCl number

• (20 – verbrauchte ml 1 n Natronlauge)/5 = HCl-Zahl in mol/Liter Harz.

The resin is washed with deionized water and rinsed in a beaker. It is mixed with 100 ml of 1 N hydrochloric acid and allowed to stand for 30 minutes. The entire suspension is rinsed in a glass column. Another 100 ml of hydrochloric acid are filtered through the resin. The resin is washed with methanol. The procedure is made up to 1 000 ml with deionised water. Of these, 50 ml are titrated with 1 N sodium hydroxide solution.

• (20 - consumed ml of 1 N sodium hydroxide solution) / 5 = HCl number in mol / liter of resin.

The amount of strongly basic groups is equal to the sum of NaNO ₃ number and HCl number.

The Amount of weakly basic groups is equal to the HCl number.

Determination of the amount of basic aminomethyl groups in aminomethylated or dimethylated crosslinked polystyrene polymer beads

100 ml of the aminomethylated bead polymer are placed on the tamping volumeter vibrated and subsequently with deionised water in a glass column rinsed. In 1 hour and 40 minutes 1000 ml of 2 wt .-% sodium hydroxide solution are filtered through. Subsequently DI water is filtered over up to 100 ml of eluate with phenolphthalein causes consumption 0.1 n (0.1 normal) hydrochloric acid from at most 0.05 ml.

50 ml of this resin are placed in a beaker with 50 ml deionized water and 100 ml of 1N hydrochloric acid added. The suspension is stirred for 30 minutes and then in a glass column filled. The liquid is drained. There are another 100 ml of 1N hydrochloric acid on the Resin filtered in 20 minutes. Subsequently, 200 ml of methanol are filtered over. All eluates are collected and combined and with 1N sodium hydroxide solution titrated against methyl orange.

The Amount of aminomethyl groups calculated in 1 liter of aminomethylated resin according to the following formula: (200 - V) x 20 = mol of aminomethyl groups per liter of resin.

1. Preparation of a monodisperse, macroporous anion exchanger with Dimethylaminohydroxyethylgruppen and additionally weakly acidic groups

1a) Preparation of a Monodisperse Acrylonitrile-Containing Polymer Beads

In a 4 l planoidal vessel with grating stirrer, condenser, temperature sensor and thermostat and temperature recorder, an aqueous receiver of 440.4 g deionized water, 1.443 g gelatin, 0.107 g resorcinol and 0.721 g anhydrous disodium hydrogen phosphate is produced. With stirring at 150 rpm, a mixture of 500 g of water and 500 g of microencapsulated monomer droplets having a uniform particle size of 590 .mu.m was added to this original, the microencapsulated monomer droplets being composed of one capsule content 56.4% by weight of styrene, 4.6% by weight of 80% divinylbenzene, 38.5% by weight of isododecane and 0.50% by weight of tert-butyl peroxy-2-ethylhexanoate as initiator and of a capsule wall consist of a formaldehyde-cured complex coacervate of gelatin and an acrylamide / acrylic acid copolymer. To this mixture 9.15 g of acrylonitrile are added. Thereafter, the curing for 6 hours at 73 ° C and then heated to 94 ° C for 2 hours. The batch is washed on a 32 micron sieve and dried in vacuo at 80 ° C for 24 hours. 305 g of a monodisperse, macroporous polymer having a nitrogen content of 0.8% and an ACN content of 3.0% by weight calculated therefrom (ACN = acrylonitrile) are obtained.

The obtained bead polymers show a uniform particle size of 545 μ.

1b) Preparation of the amidomethylated Polymer Beads

At room temperature, 1279 ml of 1,2-dichloroethane, 235.2 g of phthalimide and 165.4 g of 29.6 wt .-% formalin submitted. The pH of the suspension is adjusted to 5.5 to 6 with sodium hydroxide solution. Subsequently, the water is removed by distillation. Then 17.25 g of sulfuric acid are added. The resulting water is removed by distillation. The batch is cooled. At 30 ° C., 63.02 g of 65% strength oleum are metered in, followed by 212.2 g of monodisperse bead polymer according to process step 1a). The suspension is heated to 70 ° C and stirred for a further 6 hours at this temperature. The reaction broth is stripped off, demineralized water is metered in and residual amounts of dichloroethane are removed by distillation.
Yield of amidomethylated bead polymer: 1000 ml
50 ml of damp resin weighed 21.2 grams
Elemental Analysis Composition: Carbon: 77.9% by weight; Hydrogen: 5.4% by weight; Nitrogen: 5.0% by weight;

1c) Preparation of the aminomethylated Polymer Beads

To 975 ml of amidomethylated bead polymer from example 1b) Added 1403 g of 13.5 wt .-% sodium hydroxide solution at room temperature. The suspension is at 180 ° C heated and stirred for 8 hours at this temperature.

The resulting bead polymer is washed with deionised water.
Yield: 770 ml
Elemental Analytical Composition: Carbon: 81.7% by weight; Hydrogen: 7.9% by weight; Nitrogen: 7.2% by weight; Oxygen: 2.7% by weight
Content of the resin of aminomethyl groups: 1.72 mol / l

It be several approaches of 1c).

1d) Reaction of the aminomethylated resin in an anion exchanger with dimethylamino groups

2250 ml of deionized water, 581.2 g of formalin 29.3% by weight and 1500 ml of the aminomethylated Anion exchanger from Example 1c) are initially charged in a reactor. The suspension is at 40 ° C heated. With 307, 2 g of formic acid 85% by weight the pH is adjusted to pH 3. Subsequently, will at 55 ° C heated and at 55 ° C for 30 minutes touched. Then it is at 70 ° C heated and at 70 ° C for 30 minutes touched. Then it is heated to 80 ° C and 30 minutes at 80 ° C touched. Subsequently is at reflux temperature heated. While During the entire heating phase, the pH is increased by adding formic acid pH 3 maintained. After reaching the reflux temperature of the pH value by addition of formic acid and then sulfuric acid lowered pH 2. It is stirred for 30 minutes at pH 2. Then the pH value lowered to pH 1 and stirred for a further 8.5 hours at this pH.

After cooling, the resin is transferred to a column and washed with deionized water. Then 3 liters of 5 wt .-% sodium hydroxide solution are filtered over in 3 hours. Thereafter, the resin composition is washed with deionized water.
Yield: 1900 ml
Content of the resin of dimethylamino groups: 1.15 mol / l
Volume of the resin as supplied (free base form): 100 ml
Volume of the resin in the chloride form: 128 ml
Volume of the resin in the free base form: 100 ml

1e) reaction of the anion exchanger with tertiary Amino groups to an anion exchanger with Dimethylaminohydroxyethylgruppen

In To a reactor are added 962 ml of deionized water 2800 ml of anion exchanger from 1d). At room temperature, 335.8 grams in 30 minutes Dosed 2-chloroethanol. In 1.5 hours is heated to 50-55 ° C. Here, the pH value by pumping 20 wt .-% sodium hydroxide solution kept at pH 9. It is stirred for a further hour at pH 9. Then the pH is adjusted to 9.5 and for an additional hour pH 9.5 stirred. The pH is raised to pH 10 and stirred for a further hour at this pH. The pH value is then increased to pH 10.5 and stirred for a further hour at this pH.

Subsequently, the suspension is cooled. The resin is filtered through a sieve washed with demineralized water and transferred to a glass column. 2000 ml of 3 wt .-% hydrochloric acid are filtered over the resin composition in 2 hours. Then 101 fully desalted water are filtered over. Yield: 4100 ml Average bead diameter: 0.832 mm Effective grain size: 0.757 mm Uniformity coefficient: 1,079 Spring water content: 62.8% stability in original condition: 99% whole pearls after the rolling test: 90% whole pearls after the swelling stability test: 99% whole pearls after the syringe test: 92% whole pearls Total capacity NaCl number: 0.71 mol / l NaNO3-number: 0.71 mol / l HCl number: 0.11 mol / l

1d ') Reaction of the aminomethylated resin in a strongly basic Anion exchanger with trimethylammonium groups

1345 ml of deionized water, 1500 ml of the aminomethylated anion exchanger from Example 1c) and 187.3 ml of 50 wt.% Sodium hydroxide are in presented to a reactor. The suspension is heated to 40.degree. It 276.5 ml of chloromethane are added and then further 16 hours at 40 ° C touched.

After cooling the batch, the resin is washed out on a sieve with water and transferred to a column. From above, 3,000 ml of 3% strength by weight aqueous hydrochloric acid are filtered through. Subsequently, further 5000 m of demineralized water are filtered over. Yield: 1410 ml Average bead diameter: 0.816 mm Effective grain size: 0.764 mm Uniformity coefficient: 1,091 Spring water content: 65.3%

stability

• in original condition: 99% whole pearls
• after the rolling test: (still to be determined)% whole beads
• after the swelling stability test: (to be determined)% whole pearls
• after the syringe test: (still to be determined)% whole beads

• Nutzbare Kapazität: 0,39 mol/l

Total capacity NaCl number: 0.53 mol / l NaNO3-number: 0.75 mol / l HCl number: 0.09 mol / l

• Usable capacity: 0.39 mol / l

Claims (12)

Monodisperse or heterodisperse, gel or macroporous, medium or strong base anion exchangers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups, characterized in that R _{1 is} C ₁ -C ₄ alkyl, or a hydroxyalkyl group with C ₁ -C ₄ alkyl, R _{2 is} C ₁ -C ₄ alkyl or is a hydroxyalkyl group with C ₁ -C ₄ alkyl, R _{3 is} H and / or Na and / or K, R _{4 is} C ₁ -C ₄ alkyl or a hydroxyalkyl group with C ₁ -C ₄ alkyl and m is an integer 1, 2, 3 or 4. Anion exchanger according to claim 1, characterized in that R _{1 is} CH ₃ , R _{2 is} CH ₃ , R _{3 is} H and / or Na and / or K, R _{4 is} CH ₃ and m is an integer 1 , 2, 3 or 4 stands. Anion exchanger according to claim 1 or 2, characterized in that it comprises the composition according to the general formula (I)

where x = 0.01-0.3 y = 0.7-0.99 z = 0.01-0.2 A for H or C ₁ -C ₄ alkyl, m is an integer of 1 to 4, R _{1 is} C ₁ -C ₄ -alkyl or a hydroxyalkyl group with C ₁ -C ₄ -alkyl, R _{2 is} C ₁ -C ₄ -alkyl or a hydroxyalkyl group with C ₁ -C ₄ -alkyl, R _{3 is} H and / or Na and / or K and R _{4 is} C ₁ -C ₄ -alkyl or a hydroxyalkyl group with C ₁ -C ₄ -alkyl, with

the polymer backbone is indicated. Process for the preparation of monodisperse or heterodisperse, gel or macroporous, medium or strong base anion exchangers based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R ₂ and / or (CH ₂ ) _m NR ₁ R ₂ R ₄ groups in which R _{1 is} C ₁ -C ₄ -alkyl or a hydroxyalkyl group with C ₁ -C ₄ -alkyl, R _{2 is} C ₁ -C ₄ -alkyl or is a hydroxyalkyl group with C _l -C ₄ alkyl, R _{3 is} H and / or Na and / or K, R _{4 is} C ₁ -C ₄ alkyl or a hydroxyalkyl group with C ₁ -C ₄ alkyl and m is an integer 1, 2, 3 or 4. characterized in that a) monomer droplets from a mixture of at least one monovinylaromatic compound, at least one polyvinylaromatic compound, a (C ₁ -C ₄ alkyl) acrylic compound, optionally an initiator or an initiator combination and optionally a porogen to a crosslinked bead polymer and b) the resulting bead polymer of a) functionalized with weakly basic anion-exchanging aminomethylene groups and in this step, which includes a treatment with aqueous saponification agents, preferably a natronalkalische treatment, the copolymerized (C ₁ -C ₄ alkyl) acrylic compounds to (C C ₃ -C ₄ -alkyl) acrylic groups with the COOR ₃ radical and c) the resulting bead polymer from b), which now contains weakly basic anion-exchanging aminomethylene groups, to anion exchangers with medium and / or strong base anion-exchanging groups with additional carboxyl groups C. OOR ₃ converts Use of the anion exchanger according to claims 1 to 3 for removing anions from aqueous or organic solutions, to remove anions from condensates, to remove color particles from aqueous or organic solutions, for removal of organic components from aqueous solutions, for purification and workup of waters in the chemical and electronics industries, in particular for the production of ultrapure water or in combination with gel and / or macroporous Cation exchangers for demineralization of aqueous solutions and / or condensates. Use of the monodisperse form of the anion exchanger according to claim 5, characterized in that the removal of anions from aqueous solutions used in hydrometallurgy. Use according to claim 6, characterized in that the removal of anions in the Hydrometallurgy at R.I.P. Processes or in-situ leach processes is used. Use according to claims 6 and 7, characterized in that valuable metals are obtained. Use according to claim 8, characterized in that as valuable metals iron, cobalt, nickel, manganese, Lead, zinc, manganese, zinc, cadmium, uranium, copper, gold or silver be won. Use according to claim 9, characterized in that the uranium previously leached by acids or aqueous sodium carbonate solution has been. Process for the recovery of valuable metals from Hydrometallurgieprozessen or for the treatment of wertmetallhaltiger waters characterized in that monodisperse, gel or macroporous anion exchanger based on at least one monovinylaromatic compound and at least one polyvinylaromatic compound containing both carboxyl groups COOR ₃ and - (CH ₂ ) _m NR ₁ R. ₂ and / or - (CH ₂ ) _m NR ₁ R ₂ R ₄ groups, are used. Method according to claim 11, characterized in that the use in hydrometallurgy in R.I.P. Processes or in-situ leach processes.