Claims
- 1. A process for the removal of an anionic substance from an aqueous solution, which process comprises bringing said solution into contact with a cationic adsorption agent which has been obtained by reaction of
- (a) an amino compound which contains at least one amino group and at least one free or methylolated carboxamide group, with
- (b) an aminoplast precondensate which does not contain an amino group, in a ratio of 1 mole of component (a) per 0.2 to 10 moles of component (b), in an aqueous medium at a pH value between about 2 and 7.
- 2. A process according to claim 1, wherein the anionic substances are anionic dyes, fluorescent whitening agents, textile or dyeing assistants, surfactants, tannins or mixtures thereof.
- 3. A process according to claim 1, wherein the removal of the anionic substances is carried out in the temperature range from 2.degree. to 150.degree. C.
- 4. A process according to claim 1, wherein the removal of the anionic substances is carried out by the stirring or fixed bed method.
- 5. A process according to claim 1, wherein the cationic adsorption agent is mixed with activated carbon.
- 6. The process of claim 1, wherein the component (a) of the adsorption agent is an amino compound of the formula ##STR6## wherein m is 1 to 5, each of R.sub.1, R.sub.2 and R.sub.3 independently is hydrogen, lower alkyl which is unsubstituted or substituted by halogen, hydroxyl, lower alkoxy or cyano, or is cycloalkyl, benzyl or a group of the formula ##STR7## or R.sub.1 and R.sub.2, together with the nitrogen atom to which they are attached, represent a 5- or 6-membered heterocyclic radical, or, if m is 2, R.sub.2 and R.sub.3, together with the grouping >N--Q--N< which links them, represent a divalent 5- or 6-membered heterocyclic radical, or, if m is greater than 2, each R.sub.3, or individual substituents R.sub.3, together with the adjacent R.sub.3 and the grouping >N--Q--N< which links them, also represent a divalent 5- or 6-membered heterocyclic radical, each of Q and Q.sub.1 independently is alkylene of 1 to 8 carbon atoms, X is hydrogen or --CH.sub.2 OH, and Y is hydrogen, lower alkyl or --CH.sub.2 OH.
- 7. The process of claim 6, wherein component (a) of the adsorption agent is an amino compound of the formula (1), wherein m is 1 or 2.
- 8. The process of claim 7, wherein component (a) of the adsorption agent is an amino compound of formula (1), wherein each of R.sub.1, R.sub.2 and R.sub.3 independently is hydrogen, lower alkyl, benzyl or a group of formula (2), or R.sub.1 and R.sub.2 together with the nitrogen atom to which they are attached represent a 5- or 6-membered heterocyclic radical, or, if m is 2, R.sub.2 and R.sub.3, together with the grouping >N--Q--N< which links them, is a piperazino ring, and each of Q and Q.sub.1 is C.sub.1 -C.sub.3 alkylene.
- 9. The process of claim 8, wherein component (a) of the adsorption agent is an amino compound of formula (1), wherein each of R.sub.1, R.sub.2 and R.sub.3 is hydrogen, lower alkyl or benzyl.
- 10. The process of claim 9, wherein component (a) of the adsorption agent is an amino compound of formula (1), wherein m is 1.
- 11. The process of claim 10, wherein component (a) of the adsorption agent is an amino compound of formula (1), wherein Q.sub.1 is ethylene or propylene, each of R.sub.1 and R.sub.2 is lower alkyl, Y is hydrogen and X is --CH.sub.2 OH.
- 12. The process of claim 1, wherein components (a) and (b) together contain at least two N-methylolamide groups.
- 13. The process of claim 1, wherein component (b) is a methylolated urea or amino-1,3,5-triazine, each of which is unetherified or etherified.
- 14. The process of claim 13, wherein component (b) is a N-methylol urea or N-methylol melamine.
- 15. The process of claim 14, wherein component (b) is N,N'-dimethylol urea or tri- to hexa-methylol melamine.
Priority Claims (2)
Number |
Date |
Country |
Kind |
6036/79 |
Jun 1979 |
CHX |
|
869/80 |
Feb 1980 |
CHX |
|
Parent Case Info
This is a divisional of application Ser. No. 162,275 filed on June 23, 1980, now U.S. Pat. No. 4,316,005, issued Feb. 16, 1982.
US Referenced Citations (3)
Divisions (1)
|
Number |
Date |
Country |
Parent |
162275 |
Jun 1980 |
|