Comparative study on the selective chalcopyrite bioleaching of a molybdenite concentrate with mesophilic and thermophilic bacteria

This study evaluates different bioleaching treatments of a molybdenite conc entrate using mesophilic and thermophilic bacterial cultures. Further studi es on the chemical leaching and the electrochemical behavior of the MoS2 co ncentrate were carried out. Bioleaching tests showed a progressive removal of chalcopyrite from the molybdenite concentrate with an increase in temper ature. Chemical leaching tests support the idea of an indirect attack of th e concentrate. Electrochemical tests indicate that chalcopyrite dissolution is favored when molybdenite is present. Therefore, this type of bioleachin g treatment could be applied to purify molybdenite flotation concentrates b y selectively dissolving chalcopyrite. (C) 2001 Federation of European Micr obiological Societies. Published by Elsevier Science B.V. All rights reserv ed.