Optimization of Effective Parameters on Copper Bioleaching from Low-Garde Sulfide Ore from Shahrbabak Copper Complex

In this paper, the effective parameters on bioleaching of copper from low grade copper-sulfide ore from Shahrbabak copper complex were investigated using design of experiments. Mesophelic bacteria of A. ferrooxidans (T.f) and A. thiooxidans (T.t) were used. A two-factorial methodology was used to find the effective parameters. Response surface methodology was applied to optimize the leaching of copper. The individual effects and possible interactions of pulp density, percent of T.t bacteria and amount of Fe on the bioleaching of copper were investigated. The optimum conditions were determined using statistical analysis and analysis of variance (ANOVA). The optimum conditions for the copper recovery of 99.4% were pulp density of 7.55 g/mL, 80% of T.t bacteria and 20 g/L of Fe. Also, the most effective factor for the copper recovery was the percent of T.t bacteria. Furthermore, the statistical analysis indicates that the model fits the experimental data well.