EP2173486A2

EP2173486A2 - Method for producing chelate resins

Info

Publication number: EP2173486A2
Application number: EP08786056A
Authority: EP
Inventors: Reinhold Klipper; Michael Schelhaas
Original assignee: Lanxess Deutschland GmbH
Current assignee: Lanxess Deutschland GmbH
Priority date: 2007-07-23
Filing date: 2008-07-11
Publication date: 2010-04-14
Also published as: WO2009013149A3; US20100252506A1; DE102007034732A1; WO2009013149A2; CN101754809A; CN101754809B; US8506818B2

Abstract

The invention relates to a method for producing novel chelate resins based on cross-linked perl polymers arising from (meth)acrylic compounds having aminomethyl groups and/or aminomethyl nitrogen heterocyclic groups as functional groups possessing a high capacity for absorbing heavy metals and rapid kinetics.

Description

Process for the preparation of chelate resins

The present invention is a process for the preparation of novel chelating resins based on crosslinked bead polymers which are prepared from (meth) acrylic compounds with aminoalkyl groups and / or aminoalkyl nitrogen heterocyclic groups as functional groups which have a high absorption capacity for heavy metals.

For a long time, ion exchangers have been used to remove valuable metals and heavy metals such as tin, cobalt, nickel, copper, zinc, lead, uranium, bismuth, vanadium, platinum group elements such as ruthenium, osmium, iridium, rhodium, palladium, platinum and precious metals Gold and silver used in particular from aqueous solutions. For this purpose, chelating resins are preferably used in addition to cation or anion exchangers.

The use of chelating resins for removing heavy or valuable metals is described, for example, in R. Hering, Chelating Ion Exchange, Akademie Verlag, Berlin, 1967, pages 150 to 157. Can be mentioned u.a. Chelate resins with iminoacetic acid groups. Chelating resins in many cases show a significantly higher selectivity for heavy metals than, for example, cation exchangers with strongly acidic sulfonic acid groups.

The common ion exchangers absorb heavy metals from aqueous solutions at pH> 4. At pH values less than about 4, the selectivity of chelating resins for heavy metals decreases because their functional groups are protonated. However, the removal of heavy metals from solutions or suspensions having strongly acidic pH's in the range of about 4 to about 1 is of considerable technical interest.

For the extraction of valuable metals, rocks are treated with sulfuric acid. The precious metals are dissolved out of the rock and are present in the strongly acidic rock sulfuric acid suspension. In addition to valuable metals, the rocks often contain iron, which is often dissolved as iron 3+ ion. Ion exchangers pick up iron 3+ ions easily, but then release them again to the same extent during the regeneration of the ion exchanger. Iron ions thus block the exchange capacity of the ion exchanger.

We are looking for ion exchangers that can selectively absorb precious metals from acidic solutions or suspensions.

In US-A 4,098,867 and US-A 4,031,038 chelating resins are described which carry methylaminopyridine groups. They are prepared by halomethylation of a styrene-divinylbenzene-based bead polymer, on average 0.1 to 1.0 halomethyl groups per aromatic nucleus being introduced as a reactive group for addition of the aminomethylpyridine chloride functionality.

The limitation of the degree of halomethylation of the bead polymer also limits the amount of aminomethylpyridine groups in the chelate resin and thus the exchange capacity of the chelate resin.

It was an object of the present invention to provide a highly functionalized, high-capacity chelate resin which effectively adsorbs valuable metals from aqueous solutions even in the presence of iron ions.

Solution to the problem and thus the subject of the present invention are monodisperse or heterodisperse chelating resins with aminoalkyl groups and / or aminoalkyl nitrogen heterocyclic groups as functional groups characterized in that they are prepared based on crosslinked bead polymers of (meth) acrylic compounds by reaction with diamines and subsequent functionalization with Halomethylstickstoffheterocyclen ,

In a preferred embodiment, the present invention relates to a process for the preparation of chelate exchangers with aminomethyl groups and / or aminomethyl-nitrogen heterocyclic groups, characterized in that

a) reacting monomer droplets of at least one (meth) acrylic compound, at least one polyvinyl aromatic compound and / or a multifunctionally ethylenically unsaturated compound and an initiator or an initiator combination and optionally a porogen to give a crosslinked peripolymerizate,

b) reacting this crosslinked peripolymer with liquid diamines and

c) reacting the aminated peripolymer with halomethyl nitrogen heterocycles to chelate exchangers with aminomethyl groups and / or aminomethyl nitrogen heterocyclic groups.

According to the invention, the chelate exchangers obtainable after stage c) have functional groups of the structures -alkyl-NR ₃ and / or -alkyl-N (P),, in which R is hydrogen or a methyl group and P is methyl and / or a methyl-nitrogen-heterocyclic radical X is an even number 1, 2 or 3 and alkyl is ethyl and propyl.

The chelate exchangers according to the invention have a gel-like or macroporous structure. In process step a), at least one (meth) acrylic compound and at least one polyvinylaromatic compound and / or a multifunctionally ethylenically unsaturated compound are used. However, it is also possible to use mixtures of two or more (meth) acrylic compounds with optionally additional monovinylaromatic compounds and mixtures of two or more polyvinylaromatic compounds.

Acrylic esters or methacrylic esters with branched or unbranched C ₁ -C 6 -alkyl radicals are preferably used as (meth) acrylic compounds in the context of the present invention in process step a). Particular preference is given to using methyl acrylate, acrylonitrile or methacrylonitrile.

Preferred polyvinylaromatic compounds for the purposes of the present invention are for process step a) multifunctional ethylenically unsaturated compounds, particularly preferably divinylbenzene, divinyltoluene, trivinylbenzene, divinylnaphthalene, trivinylnaphthalene, 1,7-octadiene, 1,5-hexadiene, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate or allyl methacrylate.

The polyvinylaromatic compounds are preferably used in amounts of 1-20 wt .-%, more preferably 2-12 wt .-%, particularly preferably 4-10 wt .-%, based on the monomer or its mixture with other monomers. The type of polyvinylaromatic compounds (crosslinkers) is selected with regard to the later use of the bead polymer. Divinylbenzene is particularly preferred in many cases. For most applications, commercial divinylbenzene grades, which in addition to the isomers of divinylbenzene also contain ethylvinylbenzene, are sufficient.

In a preferred embodiment of the present invention, microencapsulated monomer droplets are used in process step a), the materials suitable for microencapsulation of the monomer droplets being suitable for use as complex coacervates, in particular polyesters, natural and synthetic polyamides, polyurethanes, polyureas.

Gelatin is preferably used as the natural polyamide. This is used in particular as coacervate and complex coacervate. Gelatin-containing complex coacervates within the meaning of the invention are understood to mean, in particular, combinations of gelatin with synthetic polyelectrolytes. Suitable synthetic polyelectrolytes are copolymers with incorporated units of, for example, 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 glutaric dialdehyde. The encapsulation of monomer droplets with gelatin, gelatin-containing coacervates and gelatin-containing complex coacervates is disclosed in EP-A 0 046 535 - A - described in detail. The methods of encapsulation with synthetic polymers are known. For example, phase interfacial condensation in which a reactive component dissolved in the monomer droplet, preferably an isocyanate or an acid chloride, is reacted with a second reactive component dissolved in the aqueous phase, preferably an amine, is suitable.

The optionally microencapsulated monomer droplets contain an initiator or mixtures of initiators to initiate the polymerization. Initiators which are preferably suitable for the process according to the invention are peroxy compounds, particularly preferably 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-dimethyl hexane or tert-amyl peroxy-2-ethylhexane, and azo compounds, particularly preferably 2,2 ^'azobis (isobutyronitrile) or 2,2'-azobis (2-methylisobutyronitrile) ,

The initiators are preferably used in amounts of from 0.05 to 2.5% by weight, particularly preferably 0.1 to 1.5% by weight, based on the monomer mixture.

As further additives in the optionally microencapsulated monomer droplets optionally porogens can be used to produce a macroporous structure in the spherical polymer. For this purpose, organic solvents are suitable which dissolve or swell the resulting polymer poorly. Hexane, octane, isooctane, isododecane, methyl ethyl ketone, butanol or octanol and their isomers are preferably mentioned. Without the addition of porogen gelatinous chelating resins are obtained.

The terms microporous or gelfbrmig or macroporous have already been described in detail in the literature. Preferred bead polymers in the context of the present invention, prepared by process step a), have a macroporous structure.

The bead polymers from process step a) can be used in heterodisperse or monodisperse bead sizes distribution.

Heterodisperse bead polymers have bead diameters in the range of 100 μ to 2000 μ.

Monodisperse in the present application refers to those bead polymers or chelate resins in which at least 90% by volume or by mass of the particles have a diameter which lies in the interval with the width of + 10% of the most frequent diameter around the most frequent diameter.

For example, for a bead polymer having the most common diameter of 0.5 mm, at least 90 volume% or mass% is in a size interval between 0.45 mm and 0.55 mm, for a fabric with the most common diameter of 0.7 mm, at least 90% by volume or mass% is in a size range between 0.77 mm and 0.63 mm.

The most common bead diameter of monodisperse bead polymers from process step a) is in the range from 100μ to 2000μ.

According to the invention, the monodispersity of the bead polymers in stage a) is obtained by atomization (jetting) or by seed-feed method. For example, such processes and monodisperse ion exchangers prepared therefrom are described in US Pat. No. 4,444,961, EP-A 0 046 535, US Pat. No. 4,419,245 or WO 93/12167.

The formation of macroporous bead polymers can be carried out, for example, by adding inert materials (porogens) to the monomer mixture during the polymerization. As such, especially organic substances are suitable which dissolve in the monomer, but poorly dissolve or swell the polymer (precipitant for polymers), for example aliphatic hydrocarbons (Farbenfabriken Bayer DBP 1045102, 1957, DBP 1113570, 1957).

In US Pat. No. 4,382,124, for example, alcohols having from 4 to 10 carbon atoms are used as porogen for the preparation of monodisperse, macroporous styrene / divinylbenzene-based bead polymers. Furthermore, an overview of the production methods of macroporous bead polymers is given.

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

The mean pond size of the optionally encapsulated monomer droplets is 10-1000 μm, preferably 100-1000 μm. In the preparation of the monodisperse 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 rhodamd and ammonium rhodanide. 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, for example, N, N-diethylhydroxylamine, N-isopropylhydroxylamine and also sulfonated or carboxylated N-alkylhydroxylamine or N, N-dialkylhydroxylamine derivatives, hydrazine derivatives such as, for example, N, N-hydrazinodiacetic acid, nitroso compounds such as, for example, N-nitrosoamine derivatives. phenylhydroxylamine, N-nitrosophenylhydroxylammonium salt or N-nitrosophenylhydroxylamine aluminum salt. The concentration of the inhibitor is 5-1000 ppm (based on the aqueous phase), preferably 10-500 ppm, particularly preferably 10-250 ppm.

The polymerization of the optionally microencapsulated monomer droplets to give the spherical, monodisperse bead polymer takes place, as already mentioned above, if appropriate in the presence of one or more slot 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 (meth) acrylic acid and (meth) acrylic acid esters. 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 is generally 0.05 to 1 wt .-% based on the aqueous phase, preferably 0.05 to 0.5 wt .-%.

If appropriate, the polymerization into a macroporous bead polymer in process step a) can also be carried out in the presence of a buffer system. Preference is given to buffer systems which adjust the pH of the aqueous phase at the beginning of the polymerization to a value between 14 and 6, preferably between 12 and 8. Under these conditions, protective colloids with carboxylic acid groups are wholly or partially present as salts. In this way, the effect of protective colloids is favorably influenced. 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 of corresponding acids and salts. The concentration of the phosphate or borate in the aqueous phase is 0.5-500 mmol / l, preferably 2.5-100 mmol / l.

The stirring speed during the polymerization is less critical and has no influence on the particle size in contrast to conventional bead polymerization. Low stirring rates are used which are sufficient to suspend the suspended monomer droplets and to assist in dissipating the heat of polymerization. Different types of stirrers can be used for this task. Particularly suitable are lattice stirrers with axial action.

The volume ratio of encapsulated monomer droplets to aqueous phase is preferably 1: 0.75 to 1:20, more preferably 1: 1 to 1: 6.

The polymerization temperature depends on the decomposition temperature of the initiator used. It is generally between 50 to 180 ⁰ C, preferably between 55 and 130 ⁰ C. The polymerization takes 0.5 to a few hours. It has proven useful to use a temperature program in which the polymerization is started at a low temperature, for example 6O ⁰ C and the reaction temperature is increased with increasing polymerization conversion. In this way, for example, the demand for safe reaction course and high polymerization conversion can be fulfilled very well. After the polymerization, the polymer is isolated by customary methods, for example by filtration or decantation, and optionally washed.

The crosslinked, heterodisperse base polymer according to process step a) and its aminolysis with polyamines according to process step b) are described in US Pat. No. 2,675,359, DD 99587 or US Pat. No. 5,414,020.

The crosslinked bead polymer to be produced according to process step a) on the basis of

(Meth) acrylic compounds is aminated in process step b) such that the

Bead polymer is reacted with either dimethylaminopropylamine or with other diamines such as ethylenediamine, Diethylentriarαinen, triethylenediamines.

Preferred other amines for the purposes of the present invention are ethylenediamine, 1-amino-3-dimethylaminopropane, triethylenetetramine, diethylenetriamine, tetraethylenepentamine, pentaethylenehexamine and their partially methylated derivatives.

The polyamines are used in molar excess, based on the ester to be aminolyzed or nitrile groups; preferably in amounts of from 1.1 to 8 mol of polyamine per mole of ester or nitrile groups, in particular from 2 to 6 mol of polyamine per mole of ester or nitrile groups.

The aminolysis can be carried out at temperatures of 80 to 25O ⁰ C, preferably 135 to 200 ⁰ C. The reaction time is generally chosen so that the nitrile or ester groups are quantitatively reacted; the achievable yield of amide groups is at least 80%, preferably at least 90%, in particular at least 95% (the remainder being converted into carboxyl groups).

In the case of amination with 1-amino-3-dimethylaminopropane, anion exchanger with tertiary amino groups is obtained directly. In the case of amination with diamines such as diethylenetriamine gives anion exchangers with primary amino groups, which can be converted by alkylation into tertiary amino groups.

The preparation of monodisperse perϊpolymers according to process step a) and their aminolysis with polyamines according to process step b) is described, for example, in US 2005/0004240 A1. In process step c), the inventive ion exchanger is prepared by reacting the aminoalkyl-containing monodisperse or heterodisperse, crosslinked, bead polymer from step b) in aqueous suspension with chloromethylpyridine or its hydrochloride or with 2-chloromethylquinoline or 2-chloromethylpiperidine.

Chloromethylpyridine or its hydrochloride can be used as 2-chloromethylpyridine, 3-chloromethylpyridine or 4-chloromethylpyridine.

The preferred reagent used in process step c) is 2-chloromethylpyridine hydrochloride, preferably in aqueous solution.

In a preferred embodiment, the reaction in process step c) is carried out with the addition of alkali, particularly preferably of potassium hydroxide solution or sodium hydroxide solution, particularly preferably of sodium hydroxide solution. By addition of alkali in the reaction of the Aminoalkylgrappen- containing, crosslinked Gnmdpolymerisates from process step b) in aqueous suspension with Halomethylstickstoffheterocyclen, preferably picolyl chloride or its hydrochloride, the pH value in the reaction in the range 4 - 10 is maintained. Preferably, the pH is maintained in the range 6-9.

In the context of the present invention, it has been found that the degree of conversion of said reaction in process step c) to a considerable extent depends on the pH of the suspension present during the reaction. Thus, according to the invention, the highest degree of conversion and thus the highest yield are achieved at pH values of 4-10, preferably at pH values of 6-9, in particular at pH values around 7.

The reaction according to process step c) is preferably carried out in the temperature range of 40 to 100 ⁰ C, particularly preferably in the temperature range of 50 to 8O ⁰ C.

The ion exchangers with chelating functional groups prepared according to the invention are suitable for the adsorption of metals, in particular heavy metals and noble metals and their compounds, from aqueous solutions and organic liquids, preferably from acidic, aqueous solutions. The ion exchangers with chelating groups prepared according to the invention are particularly suitable for removing heavy metals or noble metals from aqueous solutions, in particular from aqueous solutions of alkaline earths or alkalis, from sols of alkali chloride electrolysis, from aqueous hydrochloric acids, from wastewaters or fume gas washes, but also from liquid or gaseous hydrocarbons, carboxylic acids such as adipic acid, glutaric or succinic acid, natural gases, natural gas condensates, petroleum or halogenated hydrocarbons such as chlorinated or fluorinated hydrocarbons or fluorine / chlorine hydrocarbons. In addition, the ion exchangers according to the invention for the removal of alkaline earth metals from brines, as they are commonly used in the alkali chloride electrolysis become. However, the ion exchangers according to the invention are also suitable for the removal of heavy metals, in particular iron, cadmium or lead from substances which are reacted during an electrolytic treatment, for example a dimerization of acrylonitrile to adiponitrile.

Very particularly suitable are the ion exchangers according to the invention for removing mercury, iron, chromium, cobalt, nickel, copper, zinc, lead, cadmium, manganese, uranium, vanadium, platinum group elements and gold or silver from the solutions, liquids or gases.

In particular, the ion exchangers according to the invention are suitable for removing rhodium or elements of the platinum group and gold, silver or rhodium or noble metal-containing catalyst residues from organic solutions or solvents.

In addition to metallurgy for the production of valuable metals, the chelate exchangers with aminomethyl and / or aminoalkyl-nitrogen heterocyclic groups are outstandingly suitable for a very wide variety of fields of application in the chemical industry, the electronics industry, the waste disposal / recycling industry or electroplating or surface technology.

Untersαchungsmethoden

Determination of the amount of basic aminomethyl groups and / or aminoalkyl nitrogen heterocyclic groups in the crosslinked polystyrene bead polymer

100 ml of the aminomethylated bead polymer are shaken on the tamping volumeter and then rinsed with deionised water (deionized water) in a glass column. In 1 hour and 40 minutes 1000 ml of 2 wt .-% sodium hydroxide solution are filtered through. Subsequently, demineralized water is filtered over until 100 ml of eluate treated with phenolphthalein have a consumption of 0.1 N (0.1 normal) hydrochloric acid of not more than 0.05 ml.

50 ml of this resin are mixed in a beaker with 50 ml of deionized water and 100 ml of hydrochloric acid. The suspension is stirred for 30 minutes and then filled into a glass column. The liquid is drained off. Another 100 ml of hydrochloric acid is filtered through the resin in 20 minutes. Subsequently, 200 ml of methanol are filtered over. All eluates are collected and combined and titrated with sodium hydroxide solution against methyl orange.

The amount of aminomethyl groups in 1 liter of aminomethylated resin is calculated according to the following formula: (200-V) ^■ 20 = mol of aminomethyl groups per liter of resin. Determination of the amount of methylpyridine groups in the chelate resin

50 ml of moist aminomethylated bead polymer are dried in a drying oven at 70 ^° C. in vacuo to constant weight.

50 ml dry weigh 14.78 grams.

100 ml of the methylpyridine-bearing chelate resin in the sulfate form from Example Id) are filled into a column. From above, 400 ml 4 wt. % aqueous sodium hydroxide solution filtered over. Subsequently, from above, deionised water is filtered over to wash off the remaining sodium hydroxide solution until the eluate shows a pH of <10.

50 ml of the thus treated resin are in a drying oven at 70 ⁰ C in vacuo to constant weight dried.

50 ml dry weigh 18.47 grams.

The total dry weight of armnomethylated bead polymer (300 ml) from Example Ic) is 88.73 grams.

The total dry weight of methylene chloride-bearing inert bead polymer in the free base form (555 ml) from Example Id) is 205.04 grams.

205.04 grams - 88.73 grams = 116.31 grams.

The methylpyridine-bearing resin from Example Id) contains 116.31 grams of methylpyridine groups, corresponding to 1.264 moles of methylpyridine.

300 ml of aminomethylated bead polymer from example Ic) contain 300 × 2.17 = 651 mmol basic groups.

Each basic aminomethyl group contains two hydrogen atoms, which can be replaced by methylpyridine groups.

1,264 / 0,651 = 1.94

On a statistical average, of the two hydrogen atoms, 1.94 are replaced by methylpyridine groups.

For the purposes of the present invention, demineralized water is characterized by having a conductivity of 0.1 to 10 μS, the content of dissolved or undissolved metal ions not exceeding 1 ppm, preferably not greater than 0.5 ppm, for Fe, Co , Ni, Mo, Cr, Cu as individual Components is and not greater than 10 ppm, preferably not greater than 1 ppm for the sum of said metals.

Examples

example 1

Ionac ^® A 365 from Lanxess German Lang GmbH is a heterodisperse, macroporous anion exchanger based on a crosslinked Acrylperlpolymerisates Group A with diethylenetriamine.

a) Production of the ion exchanger with chelating groups

To 200 ml demineralized water 300 ml Ionac ^® A 365 were fed at room temperature. The suspension was heated to 90 ^° C. Subsequently, 415.7 g of an 80% strength by weight aqueous solution of picolyl chloride hydrochloride were metered in over the course of 4 hours. At the same time, the pH of the suspension was maintained at pH 7 by metering in 50% strength by weight sodium hydroxide solution. Then, stirring was continued for 6 hours at this temperature.

Thereafter, the suspension was cooled. The resin was washed free of chloride with deionized water.

Consumption of 50 wt .-% sodium hydroxide solution: 190 ml

Yield: 405 ml

25 ml of dried resin weigh 13.5 grams.

The resin was filled into a column and applied from above with 1500 ml of 4 wt .-% sodium hydroxide solution and transferred to the free base form.

Resin volume: 395 ml

Calculation of the amount of methylpyridia groups in the final product

300 ml Ionac ^® A 365 wet weigh 113.7 grams of dried.

395 ml of wet end product weighed 213.3 grams.

In the reaction of the starting material to the end product was a weight gain of 213.3 - 113.7 = 99.6 grams.

The final product contained 99.6 grams of methylpyridine, corresponding to 1.24 moles of methylpyridine. Example 2

Lewatit ^® OC 1072 from Lanxess German Lang GmbH is a heterodisperse, gel anion exchanger based on a crosslinked Acrylperlpolymerisates with dimethylamino propyl groups.

a) Preparation of the ion exchanger with chelating groups

To 200 ml of deionized water 300 ml of Lewatit OC ^® 1072 were dosed at room temperature. The suspension was heated to 90 ^° C. Subsequently, 212.8 g of an 80% strength by weight aqueous solution of picolyl chloride hydrochloride were metered in over the course of 4 hours. At the same time, the pH of the suspension was maintained at pH 7 by metering in 50% strength by weight sodium hydroxide solution. Then, stirring was continued for 6 hours at this temperature.

Thereafter, the suspension was cooled. The resin was washed chloride-free with demineralized water.

Yield: 450 ml

25 ml of dried resin weighed 6.8 grams.

Resin volume: 500 ml

Calculation of the amount of methylpyridine in the final product

300 ml of Lewatit OC 1072 ^® wet weigh 87.84 grams of dried.

500 ml wet end product weighed dried 136.0 grams.

In the reaction of the starting material to the final product was a weight gain of 136.0 - 87.84 = 48.16 grams.

The final product contained 48.16 grams of methylpyridine, corresponding to 0.523 moles of methylpyridine.

Claims

claims

1. A process for the preparation of chelating exchangers with Aminomethylgrappen and / or Aminomethylstickstoffheterocyclengruppen, characterized in that

a) monomer droplets of at least one (meth) acrylic compound, at least one polyvinylaromatic compound and / or a multifunctionally ethylenically unsaturated compound and an initiator or an initiator combination and optionally a porogen are converted into a crosslinked bead polymer,

b) reacting this crosslinked bead polymer with liquid diamines and

c) reacting the aminated bead polymer with halomethyl nitrogen heterocycles to chelate exchangers with aminomethyl groups and / or aminomethyl nitrogen heterocyclic groups.

2. The method according to claim 1, characterized in that the monomer droplets contain porogens and form after polymerization macroporous, crosslinked bead polymers.

3. The method according to claim 1 or 2, characterized in that the crosslinked

Bead polymers are formed in heterodisperse or monodisperse bead size distribution.

4. A method according to any one of claims 1 to 3, characterized in that the monomer droplets are microencapsulated with a complex coacervate.

5. The method according to any one of claims 1 to 4, characterized in that method step a) is carried out in the presence of a protective colloid.

6, A method according to any one of claims 1 to 5, characterized in that are used as (meth) acrylic compounds, acrylic acid esters or methacrylic acid esters with branched or unbranched dC ₆ alkyl radicals.

7. Chelate exchangers available through

a) reacting monomer droplets of at least one (meth) acrylic compound, at least one polyvinylaromatic compound and / or a multifunctionally ethylenically unsaturated compound and an initiator or an initiator combination, and optionally a porogen to form a crosslinked bead polymer, b) reacting this crosslinked bead polymer with liquid diamines and

8. Use of the chelate exchangers according to claim 7, characterized in that removed as heavy metals or precious metals, mercury, iron, chromium, cobalt, nickel, copper, zinc, lead, cadmium, manganese, uranium, vanadium, platinum group elements, gold or silver become.

9. Use of Chelataustauschern according to claim 7 for the removal of rhodium or platinum group elements and gold, silver or rhodium or noble metal-containing catalyst residues from organic solutions or solvents.

10. A process for the removal of heavy metals or precious metals from aqueous solutions or vapors, aqueous solutions of alkaline earths or alkalis, sols of alkali chloride electrolysis, aqueous hydrochloric acids, wastewaters or flue gas washes, groundwaters or landfill waste, liquid or gaseous hydrocarbons, carboxylic acids or liquid or gaseous halocarbons, characterized in that chelate exchangers according to claim 7 are used.