Catalytic effect of silver-bearing solid waste on chalcopyrite bioleaching: A kinetic study

Silver ion can be useful in improving chalcopyrite bioleaching efficiency. In this work, leaching kinetics of this process was investigated using silver-bearing solid waste under different chalcopyrite/solid waste ratios. Bioleaching behavior indicates that silver-bearing solid waste can enhance the bioleaching process, and the redox potential is much higher than the proposed appropriate range (380-480 mV vs Ag/AgCl) with the solid waste added. There is a positive correlation between temperature and copper extraction rate. The kinetics data fit well with the shrinking-core model. Under these leaching conditions, the bioleaching of chalcopyrite is controlled by internal diffusion with calculated apparent activation energy (E-a) of 28.24 kJ/mol. This work is possible benificial to promote the industrial application of silver catalyst in leaching of chalcopyrite.