US EPA

1509998 

Journal Article 

Evaluation of Electrodialysis for Chronic Acid Recovery and Purification at Corpus Christi Army Depot 

Davis, JS 

1991 

05 

154 

Final rept. Oct 89-Apr 91. e quantity of hazardous waste is generated during the maintenance, repair, and overhaul of a wide variety of military equipment at Army depots. Some of this waste is generated by the use of chromic acid solutions for chromium electroplating and the application and removal of chromate conversion coatings. Hazardous waste results when metal contamination builds up in the solutions to such a degree that the solutions must be disposed of as hazardous waste. Removal of this metal contamination should result in a lengthened bath life and reduced hazardous wate generation. As part of its pollution abatement and environmental control mission, the U.S. Army Toxic and Hazardous Materials Agency (USATHAMA) is pursuing R and D projects to assist depots in meeting the Army goal of a 50 percent reduction in hazardous waste by the end of 1992 compared with 1985 baseline levels. In one project, USATHAMA purchased, installed, operated, and evaluated an electrodialysis system on two chromic acid process solutions at Corpus Christi Army Depot (CCAD) in Corpus Christi, Texas. The objective of this task was to evaluate the system's ability to remove metal contamination and oxidize trivalent chromium (an impurity) to hexavalent chromium (chromic acid). 

Electrodialysis; Pollution abatement; Army facilities; Chromates; Chromic acid; Chromium; Coatings; Contamination; Control; Conversion; Electroplating; Environments; Hazardous materials; Impurities; Military equipment; Missions; Recovery; Solutions(General); Supply depots; Metal recovery; Waste minimization; Materials recovery; Army depots