The hydrochloric acid leaching of a complex zinc sulphide ore was investigated with the objective of obtaining selective dissolution. Electro-leaching experiments were carried out using a platinum gauze feeder electrode as a slurry electrode. Electrolysis under an applied potential of –300 mV permitted selective dissolution, with respect to copper, of such metals as zinc, iron and lead from a complex sulphide ore containing sphalerite, covellite, chalcopyrite, pyrite and galena. More than 95 wt% zinc extraction was demonstrated with less than 0.01 wt% copper dissolution. X-ray diffraction analysis was used to determine the phases present in both the starting material and the final residue of the leaching tests.
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