Bioleaching of chalcopyrite at 40°C by enrichment culture obtained from some fumarolic areas

摘要

We sampled many kinds of mud from some fumarolic areas in Japan and cultured bacteria from the samples using some kinds of media for bioleaching of chalcopyrite at 40°C. There was a big difference among the succession behaviour of the enrichment culture media. The bioleaching of chalcopyrite concentrate from an iron-oxide hosted copper-gold (IOCG) deposit in Chile was investigated in shake flasks with the enrichment culture. In the flasks with the enrichment cultures, the leaching rate of copper was accelerated constantly with the increase of the microorganism concentration and the oxidationreduction potential (ORP) value. But the sudden rise of the ORP value caused deceleration of the leaching rate and the upper limit of copper leached.