Chlorate-based oxidative hydrometallurgical extraction of copper and zinc from copper concentrate sulfide ores using mild acidic conditions

A hydrometallurgical method has been developed which facilitates selective extraction of copper from a copper-concentrate ore that contains a significant composition of iron. Over 98% copper extraction has been hydrometallurgically extracted from an ore that contains 24.19% Cu, 29.22% Fe, and 0.567% Zn, all weight/weight composition. Under acidic conditions and in the absence of chlorate, iron leached out more easily than copper from the copper-concentrate sample. Sodium chlorate, an oxidizing agent, was found to influence the amount of iron that stayed in the leachate. For example, a leachate containing over 98% copper was found to have less than 0.4% iron. Experimental data show that the rest of the leached iron combined with other species in the leachate such as chloride to form jarosite. This extraction was carried out at a temperature of 165 °C for 2 h in an enclosed pressure vessel, under mild acidic conditions. This high temperature hydrometallurgical technique developed in this work leads to an enhanced grade of iron-free leachate which is rich in copper.