Copper sulphate recovery from sulphide material - esp. matte from lead de-coppering by oxidative sulphuric acid leaching

摘要

The process comprises (a) grinding and pulping the lead- and copper- contg. sulphide material in a mixt. of sulphuric acid and copper sulphate soln., recycled from step (3), to give a pulp contg. 40-150 g/l copper; (b) autoclave leaching the pulp at 120-200 deg. C with injection of an oxygen-contg. gas to give an oxygen partial pressure of at least one bar; (c) sepg. the insoluble residue; (d) cooling the soln. to form copper sulphate crystals; and (e) separating the crystals and recycling the liquor to step (a). The process is esp. useful for treating lead-copper mattes from decoppering operations in lead refineries, to give high purity copper sulphate (useful e.g. in agriculture) and a residue suitable for recycling to a galena processing installation. The dependency of lead works on copper producers for handling the matte is obviated.