Optimized Leaching Conditions for Selenium from Sar-Cheshmeh Copper Anode Slimes

The recovery process of selenium from Iranian Sar-Cheshmeh copper anode slimes employing hydrometallurgical methods has been investigated. The copper anode slimes are made up of those components of  the anodes, which are not soluble in the electrolyte. They contain varying quantities of precious metals like gold, silver, selenium and tellurium. They are being extracted as a by product in the copper production process.In this paper, some parameters affecting the leaching  conditions of anode slimes in nitric acid are studied. Taguchi experimental design method is used to find out the effect of acid concentration, temperature and time.The statistical results of  the experiments show that the above parameters are important in the leaching of -10  microns fraction. The optimum conditions determined are: T = 90º C, acidity = 4 M and the leaching time = 60 min. Under these conditions, 99 % of the selenium is leached out.