Gold recovery from flotation concentrate from gold mine tailings using dissolve smelting

Gold flotation concentrate may contains relatively high concentrations of valuable metals such as iron, copper and zinc and occasionally, even precious metals such as gold. There are major components are SiO2, Fe2O3 and Al2O3, but they also contain reactive sulphide minerals such as pyrite. The sulphides in the flotation concentrate is fully converted to an oxide form during oxidative roasting, hence the chemical composition of the roasted concentrate can be considered as a copper slag. We used high temperature smelting with additives to dissolve Au from the gold concentrate into a molten copper. Gold greatly dissolved at 1600°С under a CaO/SiO2 ratio of 1.25, suggesting the increase in the dissolution of gold into molten copper with the decreasing viscosity of the molten slaglike concentrate at high temperatures.