Chalcopyrite hydrometallurgy at atmospheric pressure: 2. Review of acidic chloride process options

摘要: Abstract Hydrometallurgical process developments for the extraction of copper from chalcopyrite tend to target complex concentrates, dirty concentrates that would incur penalties if smelted or low-grade ores are thus far an uneconomic source copper. Perceived advantages chloride systems higher solubilities and iron, ease ferrous ion oxidation faster leaching kinetics compared with ferric sulfate systems, generation sulfur rather than as product sulfide oxidation. Process employ acidic, oxidising leach media containing sodium other salts temperatures up boiling points high-concentration solutions. In those processes, is thought be active agent in dissolution mechanism. Leaching conditions fall into two groups, targeting Cu(II) Cu(I) pregnant For low grade ores, usually processed heaps, use seawater naturally saline water operations may ‘economic’ choice overcome scarcity and/or cost freshwater. Few studies have been published describing disadvantages substitution freshwater processes but, sparse information available, appears efficient a solvent carrier acid oxidant The recent descriptions some iron(II)- sulfur-oxidising, salt-tolerant acidophilic microorganisms indicate diverse group could function heaps irrigated await discovery. With regard processing using instead freshwater, salt content impact directly on solution transport costs round mine (through increased viscosity specific gravity) adversely affect by-product purity.