Developing and testing electrochemical methods for treating metal salts, cyanides and organic compounds in waste streams

Electrochemical methods to process radioactive and hazardous (mixed) wastes were studied at a bench scale. Cadmium, copper, mercury, and chromium salts, cyanides, and simple organic compounds were used in the tests. Effective conditions were found to process these waste components by electrolysis. The equipment used in the tests included flow-through cells, a membrane cell, and a graphite packed bed cell. The tested methods included an open cell electrolysis, use of pulsating current, and mediated electrooxidation. The experiments demonstrated the feasibility of applying electrochemical systems to treat the studied waste components. The great advantage of electrochemical systems is that the treatment of various wastes, or streams containing selected waste components, can be accomplished in a single treatment unit. Additional advantages of electrochemical systems are their safety, ability to recycle, and the fact that they are inclined to receive a positive public perception. The tested systems are presently used at Los Alamos National Laboratory to process mixed wastes.