A complete scheme of treatment of gold-bearing ores for gold recovery by thiourea leaching

The scope of this experimental work was devoted to the preliminary evaluation of the feasibility of thiourea leaching for the extraction of gold from gold-bearing ores, at laboratory scale. The study has permitted to identify the influence of temperature, leaching agent, pulp density and leaching time on the gold dissolution from an Italian ore (5 g/t Au). Gold has been recovered from the leach liquors by adsorption onto activated carbon and subsequent electrowinning. After the optimisation of the experimental conditions of the process, a gold recovery of about 82% was obtained with a low consumption of reagents.