On the aqueous oxidation of polymetallic Cu-Zn-Pb gold-bearing sulphide ore in an autoclave

Abstract

The paper presents a study on the oxidation of polymetallic gold ore by oxygen in an autoclave. It presents optimum parameters of autoclave leaching of sulphide refractory ore in self-generated sulphuric acid solutions aiming to gel products with favourable technological characteristics from which precious and other useful metals can be recovered. A high partial oxygen pressure (1.5 MPa to 2 MPa), high leaching temperature (190 degreesC to 200 degreesC) pulp density 80 g/L to 240 g/L, ore fraction size 76 mum and leaching time up to 4 hours yield good results in rich ores. The full extent of copper and zinc conversion as well as a high extent of iron conversion has been achieved, while lead, gold and silver and a minor part of iron remain as a solid residue among gangue minerals.