Abstract: The catalytic effect of combined use of activated carbon and silver ion on improving the efficiency of the bioleaching of Yongping Copper Mine's low-grade primary copper sulfide ores was investigated through shaking flask experiment. The results show that the addition of both activated carbon and silver ion can further accelerate the dissolution velocity and rate of copper at the initial stage of bioleaching, with a leaching result better than that achieved when only activated carbon or silver ion is added. A combination of 3.0 g/L activated carbon and 2.0mg/L silver ion is most favorable to the copper leaching. In this case, the leaching rate of copper can reach 80% after 310 h bioleaching while it is only 62% and 20% respectively when only 3.0 g/L activated carbon or 2.5 mg/L silver ion is added. It is found that it is more favorable to the bioleaching of copper from low-grade primary copper sulfide ores if the low redox potential is controlled at 600～650 mV.

Key words: Bioleaching, Low-grade primary copper sulfide ore, Activated carbon, Silver ion, Catalytic effect