Chlorine-oxygen Leaching of Complex Sulfide Concentrates.
Scheiner-BJ; Thompson-DC; Smyres-GA; Lindstrom-RE
106th Ann AIME Mtg Atlanta, Georgia, 1977 Mar; (A77-86):10 pages
Two-stage, chlorine-oxygen leaching was investigated by the federal Bureau of Mines for extracting metal values from complex sulfide concentrates. Extractions of zinc, copper, lead, cadmium, and silver were in the 94 to 99 pct range, whereas arsenic, antimony, iron, and sulfur were effectively rejected to the tails. During leaching, zinc, copper, and cadmium were solubilized as chlorides. Cooling of the leach system before liquid-solids separation effectively retained lead and silver in the leach residue for subsequent dissolution as tetrachloride complexes by brine leaching. The small amounts of sulfate ion generated during the leaching were rejected from the system by addition of calcium chloride. Recovery of metallic lead and zinc from process solutions by crystallization and fused-salt electrolysis of the chlorides was shown to be feasible in a separate study.
106th Ann. AIME Mtg., Atlanta, Georgia, Mar. 6-10, 1977; TMS Paper No. A77-86, March, 1977