Cross-linked copolymers and methods thereof

Patent metadata

Field	Value
Publication number	US-9480979-B1
Application number	US-201514918722-A
Country	US
Kind code	B1
Filing date	Oct 21, 2015
Priority date	Oct 21, 2015
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

Cross-linked cyclocopolymers made up of one or more quaternary ammonium salts and sulfur dioxide as monomers. One of the quaternary ammonium salts is also an aspartic acid derivative. The cross-linked copolymers include a repeating unit with multiple chelating centers that different metal ions can bind to. The cross-linked copolymers are zwitterionic or anionic, and can be in either an acidic form or a basic form. A method for removing metal ions from an aqueous sample with these cross-linked copolymers is also described.

First claim

The invention claimed is:

1. A copolymer, comprising:
an aspartic acid derivative;
a quaternary ammonium salt; and
sulfur dioxide;
wherein:
the aspartic acid derivative, the quaternary ammonium salt and the sulfur dioxide are cyclopolymerized to form the copolymer; and
in the copolymer, a sulfur dioxide molecule connects every two molecules of the aspartic acid derivative, the quaternary ammonium salt, or both.

2. The copolymer of claim 1 , wherein the quaternary ammonium salt cross-links one polymer chain of the copolymer to another polymer chain of the copolymer.

3. The copolymer of claim 1 , wherein the aspartic acid derivative comprises a quaternary nitrogen atom.

4. The copolymer of claim 3 , wherein the aspartic acid derivative is represented by Formula A:

wherein:
R 1 is a hydrogen, a halide or an optionally substituted C 1 -C 6 alkyl group;
X − is F − , Cl − , Br − , I − , NO 3 − or other suitable monoanion other than OH − .

5. The copolymer of claim 4 , wherein R 1 is a hydrogen and X − is Cl − .

6. The copolymer of claim 1 , wherein the quaternary ammonium salt is represented by Formula B:

wherein:
R 2 -R 5 are each independently a hydrogen, a halide or an optionally substituted C 1 -C 6 alkyl group; and
Y − and Z − are each F − , Cl − , Br − , I − , NO 3 − or other suitable monoanion other than OH.

7. The copolymer of claim 1 , wherein R 2 -R 5 are each a hydrogen and Y − and Z − are each Cl − .

8. The copolymer of claim 1 , being in a basic and anionic form.

9. The copolymer of claim 1 , having a repeating unit represented by Formula 1 or Formula 2:

wherein:
R 1 -R 5 are each independently a hydrogen, a halide, an optionally substituted methyl group, or an optionally substituted ethyl group;
in Formula 1, each W − is F − , Cl − , Br − , I − , NO 3 − or other suitable monoanion other than OH − ;
in Formula 2, each M + is Li + , Na + , K + or other suitable monocation other than H + ; and
n=9-19.

10. The copolymer of claim 9 , having the repeating unit represented by Formula 1, wherein:
R 1 -R 5 are each a hydrogen; and
W − is Cl − .

11. The copolymer of claim 9 , having the repeating unit represented by Formula 2, wherein:
R 1 -R 5 are each a hydrogen; and
M + is Na + .

12. The copolymer of claim 1 , having a Pb 2+ adsorption capacity of 50-100 mg g −1 based on a total weight of the copolymer.

13. A method for making the copolymer of claim 1 , comprising:
cyclopolymerizing the aspartic acid derivative, the quaternary ammonium salt and the sulfur dioxide in the presence of an initiator and a non-aqueous solvent to form a cross-linked polyzwitterionic acid polymer; and
optionally treating the polyzwitterionic acid polymer with a base to form a cross-linked anionic polyelectrolyte polymer.

14. The method of claim 13 , wherein the initiator is azoisobutyronitrile and the non-aqueous solvent is dimethylsulfoxide.

15. A method for removing Pb 2+ from an aqueous sample, comprising:
contacting the aqueous sample with the copolymer of claim 1 to adsorb Pb 2+ from the aqueous sample onto the copolymer.

16. The method of claim 15 , wherein the copolymer has a concentration of 0.02-5.0 g L −1 in the aqueous sample.

17. The method of claim 15 , wherein the contacting is carried out at a temperature of 10-100° C.

18. The method of claim 15 , wherein the contacting is carried out at an aqueous sample pH range of 3 to 9.

19. The method of claim 15 , wherein the contacting is carried out for 5-180 min.

20. The method of claim 15 , wherein the contacting removes more than 90% of the Pb 2+ present in the aqueous sample.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Jamiu Zakariyah Abdulkareem
• Saleh Tawfik Abdo
• Ali Shaikh Asrof

Classifications

• B01D61/02

  Reverse osmosis; Hyperfiltration {; Nanofiltration} · CPC title

• B01J43/00 Primary

  Amphoteric ion-exchange, i.e. using ion-exchangers having cationic and anionic groups; Use of material as amphoteric ion-exchangers; Treatment of material for improving their amphoteric ion-exchange properties (ion-exchange chromatography processes B01D15/36) · CPC title

• C08J11/04

  of polymers · CPC title

• B01J49/00

  Regeneration or reactivation of ion-exchangers; Apparatus therefor (ion-exchange chromatography processes or apparatus B01D15/08) · CPC title

• B01D65/02

  Membrane cleaning or sterilisation {; Membrane regeneration} · CPC title