A Comparison of Metal-Loaded DOW3N Ion Exchangers for Removal of Perchlorate from Water

Abstract

In this work, an alternative class of perchlorate selective ion exchangers (known as polymeric ligand exchangers, PLEs) were prepared by loading six transition metals (Cu(II), Co(II), Zn(II), Ni(II), Fe(II), and Fe(III)) onto a commercially available chelating resin Dowex M4195 (DOW3N). The resultant PLEs (DOW3N-Me, where Me = one of the metals) were tested with respect to their perchlorate selectivity, capacity, kinetics, and regeneration efficiency through a series of batch and column experiments. Within this group of PLEs, DOW3N-Cu(II) showed the highest perchlorate capacity; all four PLEs had similar perchlorate sorption kinetics; and DOW3N-Fe(III) demonstrated better regeneration potential.

Keywords:

• Anionic ligand
• ion exchange
• ligand exchange
• perchlorate
• polymeric ligand exchanger
• water treatment

ACKNOWLEDGMENTS

Research for this project continues through NSF grant # 0553654, ENVIRON Foundation, Lafayette College EXCEL Scholars Program, and Dow Chemicals, Inc. for providing DOW3N resin. We would like to thank students of the Lafayette Society of Environmental Engineers and Scientists (SEES) as well as Thomas DeFazio for their dedicated support on this project.