Cross-linked (bisphenol-S, formaldehyde, 1,6-hexadiamine) terpolymer for the adsorption of Pb2+ ions from aqueous solutions

Patent metadata

Field	Value
Publication number	US-9796604-B2
Application number	US-201414334102-A
Country	US
Kind code	B2
Filing date	Jul 17, 2014
Priority date	Jul 17, 2014
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

A cross-linked terpolymer (BSDF) obtained by polycondensation of bisphenol-S, formaldehyde and 1,6-diaminohexane. The terpolymer is highly efficient in eliminating lead ions from aqueous solutions. The adsorption of lead ions on BSDF was studied under different conditions such as: pH, contact time and temperature. The adsorption kinetics fits Lagergren second order kinetic model that are in agreement with the low surface area as a chemisorption process. Applying BSDF on non-spiked and spiked real wastewater samples under optimum conditions revealed the high efficiency of BSDF in removing toxic metal ions.

First claim

The invention claimed is:

1. A cross-linked terpolymer having a formula (I):

wherein:
n is the number of repeating units and n is an integer from greater than 1 to 1,000.

2. The cross-linked terpolymer of claim 1 , which is in the form of a solid material having a surface area in the range of 0.720-0.750 m 2 g −1 .

3. The cross-linked terpolymer of claim 1 , which is in the form of a solid material having a pore size diameter in the range of 161.0-163.0 nm.

4. The cross-linked terpolymer of claim 1 , which is in the form of a solid material having a total pore volume in the range of 0.028-0.032 cm 3 g −1 .

5. A method of making the cross-linked terpolymer of claim 1 , the method comprising:
polycondensing bisphenol-S, formaldehyde and 1,6 diaminohexane in the presence of a solvent comprising dimethylformamide at a temperature of 70-90° C. for 22-26 hours to form the cross-linked terpolymer.

6. A method for removing metal ions from an aqueous solution, the method comprising:
contacting an aqueous solution comprising metal ions with an adsorbent comprising the cross-linked terpolymer of claim 1 .

7. The method of claim 6 , wherein after contacting, one or more metal ions are coordinated to one or more nitrogen atoms of the cross-linked terpolymer.

8. The method of claim 6 , wherein the metal ions are lead ions.

9. The method of claim 6 , wherein the contacting removes at least 90% of the lead ions from the aqueous solution.

10. The method of claim 8 , wherein the activation energy for the adsorption of lead ions onto the adsorbent is in the range of 4.0-5.0 kJ/mol.

11. The method of claim 6 , wherein the aqueous solution has a pH in the range of 5-6.

12. The cross-linked terpolymer of claim 1 , wherein n is an integer from 100 to 1,000.

13. The cross-linked terpolymer of claim 1 , which has a weight average molecular weight of 1,500-350,000 g/mol.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Al Hamouz Othman Charles Sadeq
• Saleh Awadh Tawfik Abdo

Classifications

• C02F1/285 Primary

  using synthetic organic sorbents · CPC title

• B01J41/13

  obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds · CPC title

• C08G14/00

  Condensation polymers of aldehydes or ketones with two or more other monomers covered by at least two of the groups C08G8/00 - C08G12/00 · CPC title

• C08G14/06

  and monomers containing hydrogen attached to nitrogen · CPC title

• C02F2101/20

  Heavy metals or heavy metal compounds · CPC title