Synthesis of novel chelating resins containing dithiophosphoric functionality and comparison to analogous solvent impregnated resins

Abstract

Functional polymers (III–VIII) incorporating thiophosphoric acids were synthesized. Analogous solvent impregnated resins (SIRs) were made from polyvinyl pyridine and polyvinyl benzyl ammonium types of ionic polymers by impregnation of di-(2-ethylhexyl)-dithiophosphoric acid. The polymers and their metal complexes were characterized by FTIR. Surface area measurements of the SIR-type polymer reveal surface area and pore volume reduction upon metal ion complexation. Both covalent and impregnated-type polymers show selectivity towards Cu, Cd, Ni, and Pb. Solvent impregnated resins are more effective and more selective than the covalent type of resins. Column experiments allowed collection of toxic metals from sub-ppm concentrations and clear separation between favored metal ions and other ions.

Keywords:

• Solvent impregnated resins
• Dithiophosphates
• Functional polymers
• Metal complexation
• Cd
• Pb
• Cu
• Ni
• Polymer morphology

Acknowledgments

This research was supported under grant No. 013085, Program in Science and Technology Cooperation, Office of the Science Advisor, U.S. Agency for International Development, and by grant No. 104/96/0582 from the Grant Agency of the Czech Republic. The authors express their gratitude to Dr. M. Schonfeld (Hebrew University, Faculty of Agriculture) for help with ICP measurements and R. Gargallo and Dra. A. Izquierdo (Analytical Chemistry Department, Universitat de Barcelona) for help in resin titrations. We are grateful also to Reilly Chemicals, Belgium for the gift of Reillex resins, to Bayer AG for Lewatit resin samples, and to Rohm and Haas for Amberlite resin samples. The experimental part is taken in part from the Ph.D. program work of A. G. Strikovsky presented (1998) to the Feinberg graduate school at the Weizmann Institute of Science. F. Fernández wishes to thank WIS, Fundación Campomar (Argentina), and Universidad de Buenos Aires for financial support to visit Weizmann Institute. Prof. Abraham Warshawsky holds the Rebbeca and Israel Sieff Professional Chair in Organic Chemistry. We want to thank Dr. Ying Wang for reading this manuscript and for her critical comments and suggestions. We want to thank Mark Vilensky for his work on revision of the manuscript and critical comments and suggestions.