Abstract:Leaching effect of copper smelting dust in different leaching systems was introduced. The results show that acid leaching system is more effective than water leaching system and alkali leaching system. Leaching rate of Cu, Zn, As, Cd and Fe is 99.75%, 99.81%, 86.85%, 95.85% and 57.83% respectively under the optimum acid leaching conditions including H2SO4 concentration of 2 mol/L, L/S=4, temperature of 50 ℃, leaching time of 2 h, and stirring rate of 400 r/min. Recovery rate of Cu, As, Zn and Cd from acid leaching solution is 99.70%, 98.81%, 99.47% and 99.98% respectively under the optimal conditions through process of iron powder replacement, de-arsenic with iron salt precipitation and neutralization precipitation of zinc and cadmium.