METHOD FOR REPROCESSING OF FUSED COPPER-NICKEL SULFIDE ORES CONTAINING COBALT, IRON AND PLATINUM GROUP METALS Russian patent published in 2005 - IPC

FIELD: autoclave metallurgy of fused copper-nickel sulfide materials used in reprocessing of copper-nickel mattes and Bessemer mattes.

SUBSTANCE: claimed method includes oxidative atmospheric leaching of grinded material with reversible copper-containing solution from autoclave refining of copper product at elevated temperature and with pulp aeration with oxygen-containing gas for partial nickel conversion into solution and simultaneous copper deposition. Nickel solution is separated from iron and cobalt followed by electroextraction nickel isolation to produce nickel cathodes and reversible nickel anodic liquor. Solid residue from atmospheric leaching is oxidative leached in autoclave under excessive oxidative gas pressure by using copper and sulfuric acid-containing solution. Formed copper product is separated in autoclave from nickel, cobalt and iron with copper sulfate solution at elevated temperature and excessive water steam pressure to produce pulp used in isolating copper by common methods sulfide concentrate collecting platinum group metals and reversible copper-containing solution for atmospheric leaching of raw material. Oxidative atmospheric leaching is carried out using platinum electrode and silver chloride reference electrode at pulp redox potential of (+95)-(+245) mV, temperature of 90-118°C, partial oxygen pressure 0.08-0.25 MPa in presence of sodium sulfate and water-soluble iron ions in ratio iron/sodium sulfate in starting pulp solution of (0.002-0.035):1. Starting mass ratio of copper ions in pulp solution and nickel in solid residue from atmospheric leaching is maintained at (0.02-0.15):1. As sulfate solution for oxidative leaching in autoclave reversible nickel anodic liquor with addition of predetermined copper ion amount is used. Sulfate solution containing copper and sulfuric acid is obtained by addition in reversible nickel anodic liquor calculated amount of copper-containing solution.

EFFECT: copper sulfide concentrate with decreased nickel and iron content; simplified and lower cost equipment; reduced sulfur conversion into solution.

5 cl, 1 tbl, 3 ex