Oxygen pressure acid leaching of Gacun complex Cu concentrates

Abstract

The treatment of the Gacun complex Cu concentrate with high contents of Pb, Zn, Ag, etc by oxygen pressure acid leaching was studied. It is unusual that tetrahedrite, whose treatment was rarely studied, is the primary copper mineral of the concentrates. Most of silver also occurs in the mineral. The optimum operating parameters of oxygen pressure acid leaching were established by conditional tests. Pilot scale test was carried out under the parameters, and the leaching rates of copper and zinc are as high as 97.10% and 89.83% while lead and silver are transformed into sulfate and sulfide respectively and stay in leaching residue. The copper and zinc in lixivium were reclaimed by extraction-electrowinning and purification-electrowinning, respectively, and the lead and silver in the residue were reclaimed separately by chloride leaching and thiourea leaching. The extraction rate of copper achieves 96%, and the leaching rates of lead and silver reach 90% and 95%, respectively.