Oxidation leaching of copper smelting dust by controlling potential
(School of Metallurgy and Environment, Central South University, Changsha 410083, China)
Abstract: A study was conducted for metal extraction from copper smelting dust using the oxidation leaching and control of potential technology. The effects of H2O2 dosage, H2O2 feeding speed, initial HCl concentration, leaching temperature, liquid-to-solid ratio and leaching time on metals leaching efficiencies were investigated. The following optimized leaching conditions were obtained: H2O2 dosage of 0.8 mL/g (redox potential of 429 mV), H2O2 feeding speed of 1.0 mL/min, initial H2SO4 concentration of 1.0 mol/L, initial HCl concentration of 1.0 mol/L, leaching temperature of 80 °C, initial liquid-to-solid ratio of 5:1 mL/g and leaching time of 1.5 h. Under the optimized conditions, copper and arsenic can be effectively leached from copper smelting dust, leaving residue as a suitable lead resource. The average leaching efficiencies of copper, arsenic and iron are 95.27%, 96.82% and 46.65%, respectively.
Key words: copper; smelting dust; oxidation leaching; potential