Effluent Free Electrolytic Regeneration of Ion-Exchange Resins

Abstract

The efficient and economic removal of ionic species from industrial effluents is a problem which is gaining increasing significance in today’s waste water treatment systems. Reverse osmosis and electrodialysis have successfully been used in recent years for this task. For solutions containing ionic components in relatively low concentrations (less than 100 ppm), a conventional ion-exchange technique is preferred today for economic reasons. However, the regeneration of the exhausted resin leads to an effluent which contains a multitude of the stoichiometrically required quantities of the ions used for the regeneration process, mixed with the components removed from the original feed solution. With valuable or highly toxic materials such as certain heavy metal ions it is desirable to recover these ions in as concentrated a form as possible and with a minimum of impurities.