In bioleaching at 48 °C, the impairing of galvanic effect by microorganisms was not seen as almost all of the chalcopyrite has been dissolved in 31 days in both cases, which is a result of faster leaching kinetics at higher temperature. In the absence of pyrite addition, the mesophiles did not show significant impact on copper recovery compared to the abiotic one. These results confirmed the high efficiency of chalcopyrite dissolution when pyrite coexist (Mehta and Murr, 1982)