Thiobacillus ferrooxidans bioleaching of chalcopyrite at low temperature

Bioleaching of chalcopyrite with mesophile Thiobacillus ferrooxidans was performed at a low temperature(8～10 ℃).The results showed that the leaching rate of chalcopyrite for copper in sulfuric acid medium in 90 days was only 16.08%,the leaching rate in ferric sulfate medium was 21.3%,but for bioleaching it was as high as 37.96%.The optimal conditions for chalcopyrite bioleaching with Thiobacillus ferrooxidans were pH 2.0,10% inoculation,100 mesh ore size,2% slurry concentration.At the initial stage of the bioleaching process,adding 6g/L Fe2+ would greatly enhance bioleaching rate for copper to 53.51%.