Biorecovery of copper from converter slags: Slags characterization and exploratory ferric leaching tests

This paper studies the ferric sulphate leaching of converter slag (9% Cu) in order to recover Cu through a process in which bacteria regenerate the leaching agent. For this purpose, the effect of variables such as pulp density, ferric concentration, temperature and size particle have been investigated.As the Cu extraction is limited by the physical refractoriness of slag, a mild grinding is necessary.In only 4 h more than 93% of Cu is leached with 11.5 g/L of initial ferric sulphate, D80 = 47.03, 2% of pulp density at 60 °C.