LAUSR

Abstract In order to develop a hydrometallurgical process to recover gold and silver from anode slime resulted from the treatment of copper sludge, leaching experiments of the anode slime were performed by a mixture of HCl and some oxidizing agents (H2O2, NaClO, and HNO3). Effect of the concentration of oxidizing agents, reaction temperature and time, pulp density and stirring speed on the leaching of the metals in the anode slime (Au, Ag, Cu, Sn, Ni, and Zn) was investigated. According to the results, all the metals except silver were completely dissolved into the mixture of HCl and the oxidizing agents employed in this work. However, the leaching percentage of Ag was only 10% with the mixture of HCl and either H2O2 or NaClO, while 28% of Ag was dissolved into the mixture of HCl and HNO3. Complete dissolution of silver was difficult in the presence of chloride ion.