Abstract
Detoxification and removal of hexavalent chromium (chromate: CrO4 2−) in an industrial effluent was investigated using Enterobacter cloacae HO1. This bacterium could completely reduce chromate to less toxic trivalent chromium when appropiate nutrients were supplied to the effluent. The reduction rate was strongly dependent on the amount of added carbon and energy sources, and also on cell density. Since the reduced chromium readily formed insoluble chromium hydroxides, about 40% of the reduced chromium could be removed from the treated water by centrifugation.