Abstract: A method is provided for removing chromium from a chromium containing waste material wherein the waste material is dried by indirect heating, sized to a particle size of less than 0.105 mm, mixed with alkaline and oxidizing reactants, and reacted in a reaction vessel by indirect heating using approximately the stoichiometric oxygen requirement to form a reaction material containing water soluble chromates. The reaction material is cooled and resized, and then subjected to an aqueous solvent extraction to produce a solid phase containing substantially no chromium and an aqueous phase containing water soluble chromates. This aqueous phase is subjected to evaporation resulting in a concentrated chromate phase. The waste material has been rendered non-hazardous and the chromium has been recovered as useful chromates.
Type:
Grant
Filed:
October 13, 1989
Date of Patent:
April 16, 1991
Assignee:
Chrome Technology Inc.
Inventors:
Omar Baturay, James E. Shirk, Adam L. Sigerson