Process for removing heavy-metal ions from aqueous solutions

Claim 2

A process for removing heavy-metal ions from an aqueous solution, which process comprises bringing the aqueous solution in contact with a water-insoluble adsorbent which has been produced from (1) a basic polynitrogen compound capable of being acylated; (2) an aliphatic or araliphatic carboxylic acid containing mobile substituents or a multiple bond capable of undergoing addition; and (3) a crosslinking compound which contains at least two reactive substituents and which is different from component (2).

Claim 3

A process according to claim 1, wherein the adsorbent has been produced by reacting a reaction product of the components (1) and (2) with the component (3).

Claim 4

A process according to claim 1, wherein the adsorbent has been produced by reacting a reaction product of the components (1) and (3) with the component (2), or by reacting a mixture of the components (1) and (3) with the component (2).

Claim 5

A process according to claim 1 wherein the component (1) is an oligomeric or polymeric compound containing primary or secondary amino groups.

Claim 6

A process according to claim 4, wherein the component (1) is a polyalkyleneimine having a mean molecular weight of 1,000 to 200,000.

Claim 7

A process according to claim 5, wherein the polyalkyleneimine is a polyethyleneimine having a mean molecular weight of 10,000 to 100,000.

Claim 8

A process according to claim 1, wherein the component (1) is a polyamidopolyamine from a polycarboxylic acid having 2 to 10 carbon atoms and a polyamine.

Claim 9

A process according to claim 1, wherein the component (1) is a polyamidopolyamine from a polymeric fatty acid and a polyamine.

Claim 10

A process according to claim 1, wherein the component (1) is a polyamide resin which has been obtained by reacting epihalogenohydrin with a aminopolyamide from a polyalkyleneamine and an aliphatic dicarboxylic acid having 2 to 10 carbon atoms.

Claim 11

A process according to claim 1, wherein the component (2) is a halogenoacetic acid which is unsubstituted or substituted in the α-position by the lower alkyl, lower alkoxy, hydroxy-lower alkyl, lower alkoxy- lower alkyl, lower alkyl-thio-lower alkyl, carboxy-lower alkyl, phenyl or benzyl.

Claim 12

A process according to claim 1, wherein the component (2) is chloroacetic acid.

Claim 13

A process according to claim 1 wherein the component (3) is a crosslinking compound selected from the group consisting of (a) a halogeno-diazine or halogenotriazine containing at least two mobile substituents, (b) a 2-halogeno-benzothiazole-carboxylic acid halide or -sulphonic acid halide or a 2-halogeno-benzooxazole -carboxylic acid halide or -sulphonic acid halide, (c) a halogeno-6-pyridazonyl-1-alkanoyl halide or a halogeno-6-pyridazonyl-1-benzoyl halide, (d) an anhydride or halide of an aliphatic, α,β,-unsaturated monocarboxylic or dicarboxylic acid, (e) an anhydride or halide of an aliphatic monocarboxylic or dicarboxylic acid or of an aromatic carboxylic acid containing two mobile halogen atoms, (f) a carboxylic acid N-methylolamide, N-chloromethylamide or N-bromomethylamide, (g) an unetherified or etherified N-methylolurea or N-methylolmelamine and (h) a condensation product of a diarylalkane containing at least one phenolic hydroxyl group and a halogenohydrin, or a glycerol triglycidyl ether, a toluylene diisocyanate or a tris-acryloyl-hexahydro-s-triazine.

Claim 14

A process according to claim 1, wherein the component (3) is a halogenodiazine or halogenotriazine compound containing at least two mobile substituents.

Claim 15

A process according to claim 13 wherein component (3) is a halogenodiazine or halogenotriazine containing at least two mobile substituents selected from the group consisting of (i) a s-triazine compound having at least two halogen atoms bonded to ring carbon atoms, (ii) a pyrimidine compound having at least two reactive halogen atoms, (iii) a halogenopyrimidinecarboxylic acid halide and (iv) a dihalogeno-quinoxaline-carboxylic acid halide or -sulphonic acid halide, or a dihalogeno-quinazoline-carboxylic acid halide or -sulphonic acid halide, or a dihalogeno-phthalazine-carboxylic acid halide or -sulphonic acid halide.

Claim 16

A process according to claim 14, wherein the component (3) is an s-triazine compound having at least two halogen atoms bonded to ring carbon atoms.

Claim 17

A process according to claim 15, wherein the component (3) is cyanuric chloride.

Claim 18

A process according to claim 1, wherein the adsorbent has been produced by reacting a condensation product from polyethyleneimine having a mean molecular weight of 10,000 to 100,000 and a halogenoacetic acid, which is unsubstituted or substituted in the α-position by lower alkyl, lower alkoxy, hydroxy-lower-alkyl, lower alkoxy-lower alkyl, lower alkylthio-lower alkyl, carboxy-lower alkyl, phenyl or benzyl, with a halogenodiazine compound or halogenotriazine compound containing at least two mobile substituents.

Claim 19

A process according to claim 17, wherein the adsorbent has been produced by reacting a condensation product, formed from a polyethyleneimine having a mean molecular weight of 30,000 to 40,000 and chloroacetic acid, with cyanuric chloride.