METHOD OF HYDROMETALLURGICAL RECOVERY OF METALS FROM COMPLEX ORE Russian patent published in 1998 - IPC

FIELD: hydrometallurgy. SUBSTANCE: copper and/or zinc sulfides are brought in contact with sulfuric or nitric acid to produce reaction mixture which is maintained at temperature within the range 110 to 170 C under continuous stirring, after which sulfuric and nitric acid are added in amount sufficient to form bright precipitate containing water-soluble copper, zinc, and iron sulfates and dark water-soluble precipitate containing elementary sulfur and rock refuse. Reaction mixture is also supplemented with oxygen source to speed up oxidation of sulfides into sulfates and oxidation of gaseous NO_x reaction products to regenerate nitric acid. The two precipitates obtained and entrained acid solution are removed from reaction mixture, whereupon precipitates are separated from acid solution and treated to isolate copper and/or zinc sulfates from bright precipitate, whereas acid solution is recycled into reaction mixture. EFFECT: enhanced efficiency in recovering useful metals and avoided need in sealed reactors. 7 cl, 1 dwg, 4 tbl