Abstract: The catalytic effect of adding active carbon on improving the efficiency of the bioleaching of low-grade primary copper sulfide ore using mixed thiobacillus ferrooxidans and thiobacillus thiooxidans was investigated. The results show that, in the initial stage of bioleaching, active carbonated addition can greatly accelerate the copper dissolution velocity and rate, where a dosage of 3.0g/L of active carbon is most beneficial to the copper dissolution, which is increased from 11% to 79% after 600h bioleaching, an increase of 68 percentage points compared to that in the absence of active carbon. The enhanced dissolution velocity and rate of copper can be attributed to the galvanic interaction between active carbon and chalcopyrite. The addition of activated carbon can obviously depress the iron dissolution and the bacterial oxidation of Fe2+ in solution. At the presence of active carbon, a low redox potential is more favorable to the copper dissolution than a high one for low-grade primary copper sulfide ores.

Key words: Bioleaching, Low-grade primary cooper sulfide ore, Active carbon, Catalytic effect