Saginaw Valley State University

George W Eastland, Jr

Thomas A Vivian

Robert L Wright

Described is a method of separating and recovering metal values from a waste stream containing metal hydroxides comprising the steps of providing an aqueous waste stream containing metal values including chromium; subjecting the waste stream to an oxidation process to convert the chromium to chromium (VI); precipitating the other metal values in the aqueous stream by adjusting the pH of the stream to cause the precipitations; and separately recovering the chromium (VI) from the remaining metal values. The process described pertains to separating and recovering metal values such as those from an electroplating process or an electroless process wherein the metals may be iron, cobalt, zinc, cadmium, nickel, copper, silver, aluminum and chromium. The chromium recovery step is performed by oxidizing chromium (III) to chromium (VI) preferably in the presence of a manganese catalyst and preferably utilizing ultrasound waves. The remaining metal values are separated by the use of a chelating ion exchange resin.

Growing community of inventors

Saginaw, MI, United States of America

George W Eastland, Jr