Seyyed HamidReza Tabatabaei - Iranian Babak Copper Company, ShahrBabak, Kerman, Iran

The purpose of this study is to optimize the recovery process of copper from the low-grade ore samples collected from Sarcheshmeh, Kerman, Iran. The recovery is performed through a bioleaching process with its related considerations. A mix culture of microorganisms including Sulfobacillus Acidophilus, Acidimicrobium Ferrooxidans and Sulfobacillus Thermosulfidooxidans is applied due to the potential capacity of them in the field of ferrous-iron-oxidizing processes.Box-Behnken design was selected as the Design of Experiment (DOE) method considering the four effective factors and the three levels of them. These factors include pH. Temperature, culture percentage and chalcopyrite concentration. In addition, the copper extraction percentage was considered as the response which must be optimized. It should be noted that all of the DOE and analysis of variances (ANOVA) were done using Minitab 16 Software.After ANOVA evaluation, the optimum conditions for this process by a mix culture of aforementioned strains are pH 1, a temperature of 59°C, culture percentage of 15% and chalcopyrite concentration of 19%. Under these circumstances, the best optimized copper extraction percentage of 83% will be attained.

bioleaching, DOE, Sulfobacillus Acidophilus, Acidimicrobium Ferrooxidans, Sulfobacillus Thermosulfidooxidans, optimization