Title: Recovery of valuable metals from industrial waste
Application Number: 85100731 Application Date: 1985.04.01
Publication Number: 1001993 Publication Date: 1986.07.30
Approval Pub. Date: Granted Pub. Date: 1987.05.06
International Classifi-cation: C22B7/00,C22B23/04,C22B34/30
Applicant(s) Name: Institute of Chemical Metallurgy, the Chinese Acad Address:
Inventor(s) Name: Chen Jiayong, Gao Wenkao, Zhang Rongyuan
Attorney & Agent: LI SHILIANG
Abstract:
     This invention concerns a new process of hydrometallurgy for treating multicomponent slag which contains nickel, cobalt and chromium, or also contains tungsten and molybdenum. The leading feature of the process consists in: in ammonia, ammonium carbonate extraction, reducing agent as ferrous salt or sulphite is added to reduce haxavalent chromium in the charged material, hydrolytic precipitation of trivalent chromium and extraction of the principal metals are completed in one step simultaneously in the ammonia system; nickel and a portion of cobalt in the product after evaporation of ammonia is selectively solubilized by sulfuric acid; alkali decomposition is carried out to separate tungsten and molydenum from nickel and cobalt; and then the acid-soluablized trivalent cobalt is reduced. The rate of recovery and separation of metals are higher as compared with the known technologies and the process completely eliminates the chromium contamination.
Time: 5