DE2314756A1 - Thiourea gp-contg. resin prepn. - used for selective absorption of metal ions - Google Patents

Abstract

A synthetic plastic resin contng. thiourea gps. is prepd. by reacting an opt. cross-linked polymsn. or condensation resin contng. a prim. or sec. amino gp. in the presence of a suspension agent or in soln. with thiocyanic acid or a salt at high temp.

Description

Synthetic Resins Containing Thiourea Groups The invention relates to new synthetic resins containing thiourea groups, a process for their preparation and their use for adsorbing metal ions.

It is known to make synthetic resins by condensation of thiourea, To produce thiosemi & arbazid or thiocarbazide with an aldehyde (DOS 2.128.802). However, condensation products obtained in this way have largely poor thermal stability and a low rate of adsorption to metal ions. It is from DOS 2.128.802 also known the condensation of thioureas and Aldehydes in the presence of a phenolic compound or an aromatic amine to undertake. However, it is difficult to obtain uniformly structured condensation products in this way obtain.

It has now been found that synthetic resins containing thiourea groups can be used obtained when crosslinked or containing primary and / or secondary amino groups uncrosslinked polymerization or condensation resins in the presence of a suspending agent or in solution with thiocyanic acid or salts of thiocyanic acid at elevated temperature implements.

The polymerization resins which can be used in the context of the process according to the invention are known per se. They consist of an optionally mixed polymerisation polymer of a monovinyl compound crosslinked with at least one polyvinyl compound, in the possibly in an. known way primary and / or secondary amino groups were introduced.

Examples of suitable monovinyl compounds are: Styrene, substituted styrenes such as methyl styrene, dimethyl styrene, ethyl styrene, chlorostyrene, Vinylanlsol, p-vinylbenzylamine, i-methylstyrene and vinylnaphthalene.

Examples of polyvinyl compounds include: divinylbenzene, Divinyl pyridine, divinyl toluenes, divinyl naphthalenes, diallyl phthalate, ethylene glycol diacrylate, Ethylene glycol dimethacrylate, divinylxylene, divinylethylbenzene, divinyl sulfone, polyvinyl or polyallyl ethers of glycol, glycerine and pentaerythritol, divinyl ketone, divinyl sulfide, Allyl acrylate, diallyl maleate, diallyl furnarate, diallyl succinate, diallyl carbonate, Diallyl malonate, diallyl oxalate, diallyl adipate, diallyl sebacate, divinyl sebacate, diallyl tartrate, Diallyl silicate, triallyl tricarballylate, triallylaconitate, triallyl citrate, triallyl phosphate, N, N'-methylenediacrylamide, N, N'-methylenedimethacrylamide, N, N -ethylenediacrylamide, 1,2-di (d-methylmethylene sulfonamido) ethylene, trivinylbenzene, trivinylnaphthalene, Polyvinyl anthracenes and trivinyl cyclohexane.

Examples of preferred monovinyl compounds are: Styrene, vinyl toluene and vinyl naphthalene.

Examples of preferred polyvinyl compounds include: Divinylbenzene and trivinylbenzene.

In particular, copolymers are used in a predominant proportion on monovinylaromatic compounds such as e.g. B.

Styrene, substituted styrenes (such as vinyl toluene, vinyl anisole, ethyl styrene), Vinyl naphthalenes and a minor proportion of aromatic or aliphatic Polyvinyl compounds in question.

Vinylaromatic copolymers can also be used, in the manufacture of which additives of other vinyl compounds were used, such as Methacrylic and acrylic compounds - especially acrylonitrile -, ethylene, propylene, Isobutylene, vinyl chloride, vinyl acetate, vinylidene chloride, vinyl pyridine and substituted Vinyl pyridines as well as vinyl quinolines and vinyl pyrrolidone. They are still suitable Additions of polyethylenically unsaturated compounds such as isoprene, butadiene, chloroprene, Piperylene, pentadiene, hexadiene, octadiene, decadiene, hexatriene, cyclopentadiene as well their substitution products, for example chloroprene, 2-dimethyl-butadiene, 2,5-dimethyl-hexadiene, 2,5-dimethyl-octadiene, which generally behave as if they were only one Would have a double bond.

The amount of polyvinyl compounds used as crosslinkers can fluctuate within wide limits. In general, the content of polyvinyl compounds about 1-50% by weight based on the total amount of monomers, with one content from 2-15% by weight is preferred. The vinyl compounds referred to above as additives are also generally used in amounts of 1-50% by weight, based on the total amount of monomers used, amounts of 2-15 wt. are preferred.

In the context of the process according to the invention, polymerization resins are used in particular macroporous copolymers from the mono- and polyvinyl compounds use. The production of such macroporous copolymers is known. It can be carried out by various methods (J. Seidl et al.

in Adv. Polym. Sci., Vol. 5, 1967, pp. 113 ff.).

For example, such macroporous copolymers are made by Copolymerization of the mono- and polyvinyl compounds listed above in Presence of a compound obtained that is a solvent for the monomeric mono- and represents polyvinyl compounds in which the copolymers obtained, however are practically neither soluble nor swellable. Such compounds are also known Examples include: gasoline, dodecane, isododecane, cyclohexanol, tert-amyl alcoholb Dodecanol and oleic alcohol.

Unless the polymers described above are used corresponding monovinyl compounds already have primary and / or secondary amino groups contain, these are introduced into the polymers in a manner known per se.

For example, we would like to point out the introduction of these groups on the Paths of chloromethylation and subsequent amination (USA patent 2,629,710) or via the chloromethylation and subsequent reaction with phthalimide potassium (Engl. Patent 767.821) or via the amidomethylation according to DAS 1.054.7n5 and subsequent Saponification noted. The D.P. 1.045.102 also describes the introduction such groups especially in macroporous copolymers.

Furthermore, crosslinked macroporous copolymers of the type of polyaminostyrene pointed out. which is also within the scope of the invention Process can be used as polymerization resins. She. will in general obtained in a manner known per se by filtering crosslinked macroporous Styrene polymers and reduction of nitration products obtained in this way. They are known per se, their manufacture is used, for example, in the D.P. 1,049,583.

It is also possible to use polymerization resins that by Conversion of carboxylic acid ester; or resins bearing nitrile groups with polyalkylene polyamines, e.g. B. diethylenetriamine, triethylenetetramine, tetraethylene pentamine, imino-bispropylenamine and hydroxyethyl diethylenetriamine can be obtained. These resins are known per se their manufacture, for example, in D.P. 956.449 (see also US. 2,675,359) or

Yep Appl. Sho 38-4515.

Furthermore, the polymerization resins can be crosslinked or uncrosslinked Use polyvinylamines, the production of which is also knownnand for example in DAS 1.151.120 or R. Hart, Ind. chim. belge 23 (1958) 251) is described, as well as from polyethyleneimine or from straight-chain or branched polyalkylene polyamines or their technical mixtures.

When using polymerization resins containing aromatic nuclei preference is given to using those which contain more than one amino group per aromatic Contain core and the almost exclusively primary araliphatic amino groups wear. They are obtained in a manner known per se, for example by reaction thus obtained from polystyrene polymers with chloromethylphthalimide and saponification Conversion products. These resins are known per se, for example their production in the Dutch patent 113,552. The use of such polymerization resins leads to synthetic resins according to the invention with a particularly high capacity.

The condensation resins which can be used in the process according to the invention are also known. They are generally made by condensation of aliphatic or aromatic Amines obtained with epichlorohydrin or formaldehyde.

Examples of aliphatic amines which may be mentioned are polyalkylenepolyamines such as diethylenetriamine, triethylenetetraamine, pentaethylene hexamine and polyethylene imine, as a chromatic amine, for example, m-phenylenediamine. Find preferred use macroporous condensation resins, the manufacture of which is described, for example, in D.P. 972.246 and U.S. Patent 2,389,865, respectively.

It should also be pointed out that those which can be used according to the invention crosslinked polymerization containing primary and / or secondary amino groups or condensation resins are known per se and their use as anion exchangers is described.

(R. Griesbach, Exchange Adsorption in Theory and Practice, Akademie-Verlag Berlin, pages 56-62 (1957) and Ullmann's Encyclopadie der technischen Chemie, 3rd edition, Volume 8, page 811 (1957)).

The method according to the invention is carried out when used of thiocyanic acid in general so that the primary and / or secondary amino groups containing polymerization or condensation resin dissolves in a solvent or suspended in a suspending agent, the thiocyanic acid to the solution or the suspension is added and the reaction mixture is then heated with stirring.

Are polymerization or condensation resins containing crosslinked amino groups is used, one can also proceed in such a way that the polymerization or condensation resin is used initially loaded exhaustively with thiocyanic acid in a filter tube, the so loaded Polymerization or condensation resin in water or dilute thiocyanic acid suspended and the suspension heated with stirring. With both approaches has been found to be advantageous, the acidity of the suspension is not greater than 0.01 mol / l of thiocyanic acid to choose. The acidity can too greater than 0.01 mol / l, for example 0.1-2 mol / l of thiocyanic acid, but here the reaction products are increasingly by conversion products of the Thiocyanic acid contaminates, so that in addition a purification of the reaction products is required.

The use of salts of thiocyanic acid is generally accepted in such a way that the polymerization or condensation resin containing amino groups initially with the help of an acid, for example a mineral acid such as dilute Hydrochloric acid or sulfuric acid, converted into the salt form in a manner known per se, And then dissolve in a solvent together with a salt of thiocyanic acid or suspended in a suspending agent and the solution or suspension under Stirring heated. The pH of the solution or suspension should not be used here be less than 0 and at pH values between 0 and 8, preferably at pH values lie between 1 and 6.

-It is still possible when using salts of thiocyanic acid proceed in such a way that the polymerization containing primary and / or secondary amino groups or condensation resin directly with the thiocyanate in question in a solvent dissolves or suspended in a suspending agent, and the solution or suspension heated with stirring.

The reaction times depend essentially on the reaction temperature and the type of polymerization or condensation resin used. Mentioned be further that one of the respective solutions or suspensions also to dryness concentrate and heat the residue dry. In the case of .use of crosslinked polymerization or condensation resins very compact, only a little get swellable resins.

The amount of thiocyanic acid or thiocyanate used depends essentially on the amount of amino groups contained in the polymerization or condensation resin away; however, it can vary within wide limits. So it is possible with equimolar Amounts of thiocyanate, based on the amounts of amino groups E used, to work just as one can use a ten-fold excess of thiocyanate. In general However, one will use amounts of 1 to 2 moles of thiocyanate or thiocyanic acid per mole used amino groups work.

In addition, you can also use a deficit of thiocyanate or thiocyanic acid, which gives synthetic resins which, in addition to thichurea groups still contain amino groups.

The temperature at which the reaction occurs is essentially depending on the type and structure of the used, primary andgor secondary Polymerization or condensation resin bearing amino groups. So are in general in the case of polymerization or condensation resins with primary aromatic amino groups lower temperatures are sufficient than with polymerization or condensation resins with primary aliphatic or araliphatic amino groups.

Generally one works at temperatures between 80 and 2000C, temperatures between 110 and 180 ° C. are preferred.

Such liquids can be used as solvents or suspending agents or liquid mixtures which are inert under the reaction conditions The reactants are such as water, methanol, ethanol, toluene, and chlorobenzene and mixtures of organic liquids, such as ethanol-toluene or Toluene-chlorobenzene. To what extent these liquids act as solvents or suspending agents act against the polymerization or condensation resin used depends primarily depends on whether the polymerisation or condensation resin is used non-networked or networked is. Suspending agents are preferred such liquids are used, on the one hand, swelling agents for the amino groups carrying condensation or polymerisation resin and, on the other hand, solvents for thiocyanic acid or salts of thiocyanic acid. Examples are Water, ethanol and dioxane.

Both inorganic and organic salts can be used as salts of thiocyanic acid Thiocyanates in question, in particular in the case of the inorganic thiocyanates those with metals of the 1st to 3rd group of the periodic table and in the case of the organic Those with organic bases such as aliphatic and aromatic amines and thiocyanates their quaternary ammonium salts come into question. Are particularly preferred the alkali metal thiocyanates and ammonium thiocyanate. Examples are Lithium thiocyanate, sodium thiocyanate, potassium thiocyanate, magnesium thiocyanate, calcium thiocyanate and aluminum thiocyanate.

Examples of organic thiocyanates which may be mentioned are methyl or Ethylammonium thiocyanate, benzylammonium thiocyanate and dimethylammonium thiocyanate.

In addition, mixtures of such inorganic and organic can also be used Thiocyanates are used, for example: ammonium thiocyanate / benzylammonium thiocyanate, Sodium thiocyanate / benzylammonium thiocyanate and potassium thiocyanate / benzylammonium thiccyanate.

Containing the thiourea groups prepared according to the invention Synthetic resins have a selective adsorption capacity for precious metals such as mercury, Silver and Gold.

In addition, they are great for adsorbing other metals, in particular the platinum metals. It has shown, that according to the invention manufactured synthetic resins, which are based on a macroporous polymer, a show a much higher rate of metal uptake than corresponding gel-type ones Products.

The resins according to the invention are furthermore characterized by high resistance to alkali off, for example, 10% sodium hydroxide solution only removes them at the boiling point slowly attacked.

Example 1: 625 ml of a macroporous, weakly basic anion exchanger with primary amino groups, HCl binding capacity 1.62 eq, produced in itself known way according to the procedure of the DP. 1,054,715 by amino methylation of a crosslinked with 5% divinylbenzene, and by adding 65% by weight based on the monomer mixture a C12-Eohlenwasserætoffgemisches made porous styrene polymer in pearl form, were charged to equilibrium with about 1N thiocyanic acid in a filter tube. After washing out the excess acid with water, 1000 ml of the so loaded Anion exchanger isolated in the thiocyanate form, in 500 ml deionized water suspended and in the autoclave for 7 hours.

heated to 1800C for a long time. After the abktililen was the conversion product obtained in the filter tube with deionized water, 2% sodium hydroxide solution (until the drain is practically was free of thiocyanate ions) and then again with deionized water washed (until neutral). This gave 645 ml of a synthetic resin which Contained 1.0 mmol / ml thiourea groups. (Sulfur content in the dry matter: 8.25%).

Example 2: 300 ml of the macroporous anion exchanger used in Example 1 (UL binding capacity 0.78 eq.) Were suspended in 450 ml of deionized water and converted into the HCl-boron by adding 0.78 eq hydrochloric acid. After 30 minutes 118.5 g of ammonium thiocyanate (1.56 mol) were added and the suspension in the autoclave Heated to 140 ° C. for 8 hours. The reaction product was treated accordingly Example 1. This gave 55 ml of a synthetic resin containing 1.0 mmol / ml of thiourea groups contained.

(Sulfur content in the dry matter: 8.7%).

Example 3: 300 ml of the macroporous anion exchanger used in Example 1 (HCl binding capacity 0.78 eq.) Were suspended in 450 ml of deionized water. After 30 minutes, 118.5 g of ammonium thiocyanate (1.56 moles) was added and the The suspension was heated to 140 ° C. for 8 hours in an autoclave.

After cooling, the reaction product was processed in a corresponding manner treated as in Example 1.

330 ml of a synthetic resin containing 0.64 mmol / ml thiourea groups were obtained in this way contained (sulfur content in the dry matter: 4.95%).

Examples 4-9: The procedure was as in Example 2, except that the Quantities of anion exchange resin, hydrochloric acid and ammonium thiocyanate to each other as well as the reaction time and reaction temperature varied. The received Test results are shown in Table 1.

Example 10: 300 ml of the macroporous anion exchanger used in Example 1 (HCl binding capacity 0.78 eq.) Were suspended in 450 ml of deionized water and converted into the HCl form by adding 0.78 eq hydrochloric acid. After 30 minutes 1.56 mol of potassium thiocyanate were added, and the suspension in the autoclave 16 Heated to 140 ° C for hours. The reaction product obtained was treated in the same way as in example 1.

325 ml of a synthetic resin containing 1.24 mmol / ml thiourea groups were obtained contained (sulfur content in the dry matter: 8.8%).

Example 11: That in example 1 for the production of the anion exchanger macroporous styrene bead polymer used was according to the procedure of the DP. 1,054,715 in a weakly basic anion exchange resin of the poly (aminomethylstyrene) type transferred, the reaction being carried out so that a resin was obtained which was about Contained 1.5 aminomethyl groups per aromatic nucleus.

290 ml of the anion exchange resin obtained in this way (HCl binding capacity 0.9 eq) were suspended in 500 ml of deionized water and, by adding 0.9 val hydrochloric acid converted into the HOI form. After 30 minutes there was 137 g of ammonium thiocyanate added and the reaction mixture for 16 hours.

heated to 140 ° C for a long time.

220 ml of a synthetic resin containing 1.95 mmol / ml thiourea groups were obtained contained (sulfur content in the dry matter: 13.8%).

Example 12: 500 ml of a macroporous, weakly basic anion exchanger with primary amino groups (HCl binding capacity 1.22 eq), manufactured according to DP 1.054.715 by aminomethylation of a crosslinked with 8% divinylbenzene and by addition of 60 ffi based on the monomer mixture of a C12 hydrocarbon mixture porous made.Styrene polymer in bead form, were in 500 ml of deionized Suspended water and converted into the HCl form by adding 1.22 eq hydrochloric acid.

Then 69.5 g of ammonium thiocyanate were added and the Suspension heated to 14,000 for 16 hours.

After cooling, the reaction product obtained was in the filter tube with fully demineralized water, 2% sodium hydroxide solution (until the drain is practically free of Thiocyanate ions was) and then again with fully demineralized Washed with water (until neutral flow).

585 ml of a synthetic resin containing 0.9 mmol / ml thiourea groups were obtained in this way contained. (Sulfur content in the dry matter: 8.15%).

If one proceeds in a corresponding way with the difference that instead of 69.5 g of ammonium thiocyanate, 186 g of ammonium thiocyanate are used, so a synthetic resin is obtained which contains 1.14 mmol / ml thiourea groups. Example 13: 1000 ml of the macroporous, weakly basic anion exchanger used in Example 1 @ were exhaustively loaded with 3% hydrochloric acid in a filter tube, the excess Acid displaced by elution with ethanol (technically absolute) until the water content of the eluate was 0.4%. Of the 1250 ml of anion exchange resin thus obtained in 300 ml of the HCl-ForU (with 0.62 eq amino groups) were suspended in: 500 ml of ethanol and after adding 95 g of ammonium thiocyanate in the autoclave to 14,000 for 8 hours heated.

This gave 238 ml of a synthetic resin containing 1.6 mmol / ml thiourea groups contained. (Sulfur content in the dry matter: 11.1 5 ').

Example 14: 1000 ml of the macroporous, weakly used in Example 1 basic anion exchanger were in a filter tube with water and then Washed with ethanol (technically absolute) until only 0.3% water is left in the drain was. 1560 ml of anion exchange resin swollen in ethanol were isolated.

300 ml of the anion exchanger pretreated in this way with an acid binding compound of 0.5 eq were suspended in 500 ml of ethanol and after adding 24.5 g of sulfuric acid (100%) and 76 g of ammonium thiocyanate for 8 hours at 1400C in the autoclave. The reaction product was washed thoroughly with water. 250 ml were obtained in this way of a synthetic resin containing 1.4 mmol / ml thichurea groups (sulfur content in the dry matter: 10.1%).

Example 15: 300 ml of that described in Example 14 swollen in ethanol Anion exchanger were washed with toluene in a filter tube until the drain was practically free of ethanol. Then the exchanger was in 400 ml of toluene suspended and after the addition of 25.0 g of sulfuric acid (100%) and 76 g of ammonium thiocyanate in an autoclave heated to 14,000 for 8 hours. The conversion product was washed after cooling with ethanol and then with water.

This gave 200 ml of a synthetic resin containing 1.6 mmol / ml thiourea groups contained (sulfur content in the dry matter: 11.15).

Was the procedure described above, with the only difference that that chlorobenzene was used instead of toluene, 200 ml of a synthetic resin were obtained, containing 1.4 mmol / ml thiourea groups.

Example 16: 1000 m, 1 of a weakly basic anion exchanger of the type of poly (aminomethylstyrene), produced by aminomethylation of a with 4 ffi divinylbenzene crosslinked styrene bead polymer according to DP 1.054.715, with an HCl binding capacity of 2? 75 eq were added to 1500 ml of deionized water suspended. After adding 416 g of ammonium thiocyanate, the pH of the suspension became adjusted to 1.0 by slowly adding 286 ml of concentrated hydrochloric acid. It was stirred for 30 minutes and then in the autoclave for 16 hours.

heated to 1400C.

After washing with deionized water, 1083 ml of one were obtained Synthetic resin with 1.5 mmol / ml thiourea groups (sulfur content in the dry substance: 8.9%).

Example 17: A polystyrene bead polymer crosslinked with 4% divinylbenzene was according to DP 1.054.kl5 using iron (III) chloride as a catalyst aminomethylated in a manner known per se, the reaction conditions being chosen were that the reaction product after saponification about 1,5-aminomethyl groups contained per aromatic nucleus. 145 ml of the anion exchange resin thus obtained (HCl binding capacity 0.52 eq) were suspended in 500 ml of deionized water and following the procedure described in Example 2 using of 0.52 eq hydrochloric acid converted into the HCl form and then with 80 g of ammonium thiocyanate 16 hours

long implemented at 14000. 120 ml of a synthetic resin were obtained in this way with 2.2 mmol / ml thiourea groups.

(Sulfur content in the dry matter: 12.5%).

Example 18: In polystyrene bead polymer crosslinked with 2% divinylbenzene were analogous to Example 17 according to the DP method. 1,054,715 about 2 aminomethyl groups introduced per aromatic nucleus.

236 ml of the anion exchange resin obtained in this way (HCl binding capacity 0.73 eq) were suspended in 400 ml of deionized water by adding 0.73 Val hydrochloric acid converted into the HO1 form and then after adding 111 g of ammonium thiocyanate Heated to 140 ° C for 16 hours.

150 ml of a synthetic resin containing 2.7 mmol / ml thiourea groups were obtained in this way contained (sulfur content in the dry matter: 14.15%).

Example 19: 250 g of the macroporous anion exchange resin used in Example 1 were according to D.P. 1,049,583 nitrided and then reduced.

150 ml of the macroporous anion exchange resin thus obtained from Type of poly (aminostyrene) with a ROI binding capacity of 0.22 eq were used in 220 ml of 1N hydrochloric acid are stirred for 30 minutes and after the addition of 40 g of ammonium thiocyanate heated in the autoclave for 8 hours at a temperature of 120 ° C. 128 ml of a synthetic resin were obtained in this way with 1.05 mmol / ml thiourea groups (sulfur content in the dry matter: 6.9 %).

Example 20: 135 g of a 50% strength aqueous polyethyleneimine solution were stirred with 350ml of deionized water and concentrated under cold with 106 ml Hydrochloric acid and then mixed with 238 g of ammonium thiocyanate. The slightly cloudy The solution was stirred for a further 30 minutes at room temperature and then for 16 hours 1400C heated in the autoclave.

A sample of the reaction solution was acidified to pH 1 with hydrochloric acid and dialyzed against demineralized water using an Oellophane tube, until the reaction to thiocyauations was negative. The residue was evaporated, again taken up in hydrochloric acid and dialyzed again for 24 hours. The subsequently isolated evaporation residue resulted in the elemental analysis for the ratio N: S the value 3.1 d. H. In addition to thiourea groups, the product also contained about the equal amount of amino groups.

Example 21: 200 ml of a condensation resin made from m-phenylenediamine and formaldehyde with an HCl binding capacity of Val and a water content of 82 o were concentrated in 300 ml of deionized water with stirring with 10 ml Hydrochloric acid and 14 g of ammonium thiocyanate are added and, after a residence time of 4 Hours in which a constant pH value of 0.5 was established in the suspension, in an autoclave 16 hours

heated to 160 ° C for a long time. There 75 ml of synthetic resin were isolated, the a sulfur content of 9.15% contained 1.0 mmol / ml thiourea groups.

Example 22: 150 ml of the macroporous anion exchange used in Example 1 shear resin to ((HCl binding capacity 0.4 eq) were in 200 ml of deionized Suspended water and converted into the HCl form with 0.4 eq hydrochloric acid. After 30 Minutes 45.5 g of ammonium thiocyanate and 66.5 g of benzylammonium thiocyanate were added, and the suspension in the autoclave was heated to 14,000 for 16 hours. After cooling down the reaction product was first washed with 1 l of ethanol in a filter tube and then worked up according to the procedure in Example 1 166 ml of a synthetic resin with 1.45 nMcl / ml thiourea groups (sulfur content in the dry matter: 10.05%).

Application example 1 Determination of the maximum adsorption capacity for silver and mercury: samples of the synthetic resins produced according to the invention were washed in a filter tube with 2% sodium hydroxide solution until the drain was practical Was free of thiocyanate ions and rinsed neutral with deionized water. from 25 ml samples were placed in each of the synthetic resins pretreated in this way in filter tubes a clear width of 13 mm first with aqueous nitric acid or sodium chloride solution pretreated, the concentration of nitric acid or sodium chloride solution according to those of the test solution were chosen, and then to equilibrium loaded with the test solution. The filtration rate was 200 ml per hour. The filter drain was titrimetrically examined in portions for the metal content and the absorption capacity of the resins from the feed and that in the filter drain measured amount of metal is calculated. In detail are the test data and results summarized in Table 2 below.

Application example 2 Determination of the breakthrough capacity for mercury and gold: Resin according to example 3. 14th Resin quantities in ml 80 10 Layer height of the Filter bed in cm 21.5 11 Specific load in 1 / hour / l resin 5 20 Pre-loading with - 1 n HC1 Loading solution 0.001 n HgC12 0.01 n HAuC14 in 0.02 N NaCl in 1.0 N HCl Breakthrough capacity in Mol / l resin 0.9 1.2 The loads were stopped as soon as the amounts of mercury or gold in the filter outlet had risen to 10% of the amounts contained in the inlet (breakthrough point). The breakthrough quantities determined in this way were used to calculate the breakthrough capacities. With this mercury loading, the concentration of mercury in the filter drain remained below 10 ppb for about 3/4 of the loading. The analyzes were carried out using the atomic absorption spectroscopy, the mercury analyzes using the flameless method. Table 1 Molar ratio Example of anions from: HCl: NH4SCN reaction temperature from S-Ge thiourea exchanger time rature prey hold groups in mmol Hrs. ° C ml% by weight ml implementation product 4 1: 1: 2 8 100 310 1.4 0.1 5 1: 1.1: 2 8 120 375 8.5 1.05 6 1: 1.5: 2 8 180 315 9.05 1.3 7 1: 1: 2 24 140 310 8.9 1.1 8 1: 1: 5 16 140 320 9.9 1.4 9 1: 2.5: 2 8 140 240 9.1 1.07 Table 2: Maximum adsorption capacity for silver and mercury Resin according to metal absorption in mol / l resin when loaded with Example 0.1 m Ag NO3 solution 0.05 m Hg (NO3) 2 0.05 m HgCl2 off off off 0.01 m | 0.1 m | 1.0 m 1.0 m HNO3- 1.0 m NaCl- HNO3 solution solution solution 1 1.33 1.59 1.24 1.17 3 1.40 1.48 1.66 1.0 5 1.34 6 1.64 1.98 1.0 11 2.93 2.0 14 1.82 2.2 1.37 1.23 16-18 0.01

Claims (27)

Claims: 1. Process for the production of thiourea groups containing synthetic resins, characterized in that one primary and / or secondary Crosslinked or uncrosslinked polymerization or condensation resins containing amino groups in the presence of a suspending agent or in solution with thiocyanic acid or salts the thiocyanic acid converts at elevated temperature. 2. The method according to claim 1, characterized in that as Polymerisationsharæ with at least one polyvinyl compound crosslinked polymers used from monovinyl compounds. 3 The method according to claim 1 - 2, characterized in that as Polymerization resins crosslinked with divinylbenzene used styrene polymers. 4. The method according to claim 1-3, characterized in that one Polymers of styrene and divinylbenzene used as polymerization resins, with the divinyl benzene content is 1 to 50% by weight, preferably 2 to 15% by weight, based on the total amount of monomers. 5. The method according to claim l, characterized in that as Polymerization resins Macroporous polymers made from monovinyl and polyvinyl compounds used. 6. The method according to claim 1 and 5, characterized in that one macroporous polymers made of styrene and divinylbenzene are used as polymerization resins, the divinylbenzene content being 1 to 50% by weight, preferably 2 to 15% by weight on the total amount of monomers. 7. The method according to claim 1, characterized in that as Polymerization resins Polymers of mono- and polyvinyl compounds containing aromatic cores used. 8. The method according to claim 1 and 7, characterized in that one macroporous polymers containing aromatic nuclei as polymerization resins used from monovinyl and polyvinyl compounds. 9. The method according to claim 1 and 7-8, characterized in that the polymerization resins used are polymers containing aromatic nuclei, which contain more than one amino group per aromatic nucleus. 10. The method according to claim 1, characterized in that one condensation resins used from m-phenylenediamine and formaldehyde. ii. The method according to claim 1, characterized in that as Suspending agent water used. 12. The method according to claim 1 and 10, characterized in that the suspending agent used is dioxane. 13. The method according to claim 1, characterized in that as Suspending agent ethanol is used. 14. The method according to claim 1, characterized in that the Implementation at temperatures between 80 - 2000C. 15. The method according to claim 1, characterized in that the Implementation at temperatures between 110 - 180 0C - takes place. 16. The method according to claim 1, characterized in that the polymerization or condensation resins containing primary and Z or secondary amino groups begins in the salt form. 17. The method according to claim 1, characterized in that one ammonium thiocyanate used. 18. The method according to claim 1, characterized in that one potassium thiocyanate used. 19. Adsorbent for adsorbing metal ions consisting of a thiourea group which is optionally crosslinked with at least one polyvinyl compound containing polymer of a monovinyl compound. 20. Adsorbent for adsorbing metal ions consisting of containing a thiourea group crosslinked with at least one polyvinyl compound macroporous polymer of a monovinyl compound. 21. Adsorbent according to claim 19, consisting of one with divinylbenzene crosslinked thiourea group-containing polymer composed of styrene. 22. adsorbent according to claim 20, consisting of a with divinylbenzene macroporous polymer of styrene containing crosslinked thiourea groups. 23. Adsorbent according to claim 19, crosslinked with trivinylbenzene. 24. Adsorbent according to claim 19, with ethylene glycol dimethylacrylate networked. 25. Adsorbent according to claim 19, consisting of an optionally containing thiourea groups crosslinked with at least one polyvinyl compound Polymer of a monovinyl compound containing aromatic nuclei. 26. Adsorbent according to claim 25, with more than one thiourea group per aromatic nucleus. 27. Use of the adsorbent according to claim 19-26, for selective Adsorption of mercury, gold, silver and platinum metals.