Thioanion-functionalized polypyrroles for metal ion capture

Abstract

Polypyrrole polymers functionalized with thioanions and methods for their use in metal capture applications are provided. Also provided are methods for making the polypyrroles using anion exchange techniques. The thioanion-functionalized polypyrroles have a conjugated, positively charged backbone of pyrrole units that is charge-balanced with associated thioanions.

What is claimed is: 
     
         1 . A thioanion-functionalized polypyrrole comprising:
 a conjugated, positively charged backbone of pyrrole units; and   charge-balancing thioanions associated with the conjugated, positively charged backbone of pyrrole units.   
     
     
         2 . The thioanion-functionalized polypyrrole of  claim 1 , wherein the thioanions comprise molybdenum thioanions. 
     
     
         3 . The thioanion-functionalized polypyrrole of  claim 2 , wherein the molybdenum thioanions comprise MoS 4   2−  anions. 
     
     
         4 . The thioanion-functionalized polypyrrole of  claim 1 , wherein the thioanions comprise antimony thioanions. 
     
     
         5 . The thioanion-functionalized polypyrrole of  claim 1 , wherein the thioanions comprise tin thioanions. 
     
     
         6 . The thioanion-functionalized polypyrrole of  claim 1 , wherein the thioanions comprise phosphorus thioanions. 
     
     
         7 . The thioanion-functionalized polypyrrole of  claim 2 , wherein the thioanions comprise Mo 3 S 13   2−  anions, SbS 3   3−  anions, SbS 4   3−  anions, S x   2−  anions, wherein x=1, 2, 3, 4, 5, or 6), SH 1−  anions, Sb 2 S 4   4−  anions, SnS 4   4−  anions, Sn 2 S 6   4−  anions, Sn 4 S 10   4−  anions, WS 4   2−  anions, PS 4-x O 3−  anions, wherein (x=1, 2, or 3), or a mixture of two or more thereof. 
     
     
         8 . A method of removing metal ions from a sample comprising the metal ions, using a thioanion-functionalized polypyrrole comprising:
 a conjugated, positively charged backbone of pyrrole units; and   charge-balancing thioanions associated with the conjugated, positively charged backbone of pyrrole units,   the method comprising:   exposing the thioanion-functionalized polypyrrole to the sample, wherein metal ions are adsorbed by the thioanion-functionalized polypyrrole; and   removing the thioanion-functionalized polypyrrole and the absorbed metal ions from the sample.   
     
     
         9 . The method of  claim 8 , wherein the thioanions comprise molybdenum thioanions. 
     
     
         10 . The method of  claim 9 , wherein the molybdenum thioanions comprise MoS 4   2−  anions. 
     
     
         11 . The method of  claim 8 , wherein the thioanions comprise antimony thioanions. 
     
     
         12 . The method of  claim 8 , wherein the thioanions comprise tin thioanions. 
     
     
         13 . The method of  claim 8 , wherein the thioanions comprise phosphorus thioanions. 
     
     
         14 . The method of  claim 8 , wherein the sample is an aqueous solution having a pH of no greater than 6. 
     
     
         15 . The method of  claim 8 , wherein the sample is an aqueous solution having a pH of no greater than 5. 
     
     
         16 . The method of  claim 8 , wherein the sample is an aqueous solution having a pH in the range from 0.5 to 1.5. 
     
     
         17 . The method of  claim 8 , wherein the metal ions include Ag +  ions, Hg 2+  ions, Pb 2+  ions, Cu 2+  ions, Cr 6+  ions, Tl +  ions, Cd 2+  ions, or a combination of two or more thereof. 
     
     
         18 . The method of  claim 8 , wherein the metal ions include Ag +  ions. 
     
     
         19 . The method of  claim 10 , wherein the sample is an aqueous solution having a pH in the range from 0.5 to 1.5 and the sample comprises Ag +  ions and Cu 2+  ions.