Biofilm forming and leaching mechanism during bioleaching chalcopyrite byThiobacillus ferrooxidans①
来源期刊：中国有色金属学报(英文版)2004年第2期
论文作者：傅建华 胡岳华 邱冠周 柳建设 徐竞
文章页码：383 - 387
Key words：bioleaching; bacterial attachment; biofilm forming; EM cell-chemistry
Abstract: The mechanism of attachment and leaching ofthiobacillus ferrooxidans(T.f.) on chalcopyrite were studied. The shaking flasks with bacteria were observed by SEM. The process of T.fattached to the surface of the mineral sample and the biofilm forming were described. The promoting role of the biofilm for bioleaching was discussed. The existence of Fe2+ in the exopolysaccharide layer ofT.fwas demonstrated by EM(electronic microscope)cell-chemistry analysis. These results show that under the proper growth condition of bacteria, bioleaching of chalcopyrite results in the formation of complete biofilm after 2-3 weeks. There are iron ions in the outer layer polymer of T.f., which provides the micro-environment for themselves, and can guaruntee the energy needed for the bacteria growth in the biofilm. At the same time, Fe3+ ions produced oxidize sulfide which brings about the increase of both growth rate of the bacterial and leaching rate of sulfide minerals.
