Selective Anion Binding from Water Using Soluble Polymers

Abstract

Abstract We investigated water-soluble dendrimers and polymers as ligands for selective anion binding. PAMAM Starburst dendrimers and polyethylenimine have been chemically modified to incorporate new ligands or hydrogen bonding groups at the primary amines. These molecules, along with the unmodified parent compounds, bind arsenate, chromate, and phosphate, even in the presence of competing anions such as chloride. Such systems could potentially be employed for remediation of contaminated water and soils using well-established ultrafiltration technology. Selectivity is achieved through bringing together moieties with a combination of electrostatic and hydrogen bonding capabilities. Total binding capacity for several metallooxyanions has been determined, as well as relative ion selectivity. Keywords: Anion separationDendrimerPEIUltrafiltration Acknowledgments Brandy Duran and Deborah Ehler are thanked for their assistance with ICP analysis. Andrew Trout is acknowledged for assistance in manuscript preparation. This work was funded by the Los Alamos National Laboratory Directed Research and Development Program. LAUR 98-5251, 01-4876. LANL is operated by the University of California for the U.S. Department of Energy under Contract W-7405-ENG-3.