| Popis: |
About half of the global mine production of cobalt comes from the layered sedimentary cobalt-copper ore deposits of central Africa. The deposits usually consist of a weathered surface cap over unweathered sulfide ore below. The host rock is usually siliceous dolomite. As-mined oxide ores typically contain 0.3%-0.5% Co and 3%-5% Cu. The “oxide” cap is usually mined first. The copper is recovered as high-purity cathodes by leaching, solvent extraction separation from cobalt, solution purification, and electrowinning. The cobalt is recovered from solvent extraction raffinate by solution purification followed by precipitation of cobalt hydroxide, Co(OH) 2 . The cobalt hydroxide precipitate is sold for chemical production or cobalt electrowinning. |
