토착호산성박테리아의 황철석 표면부착과 용출특성

Abstract

This study is to investigate the bioleaching of pyrite using indigenous acidophilic bacteria from the acid mine drainage. SEM was used to identify the morphology of the indigenous acidophilic bacteria and the corroded pyrite surface. When the indigenous bacteria oxidized the pyrite, the extracellular polymeric substance(EPS) was formed and coated surface of pyrite grain. The formation of the EPS was probably secreted by the indigenous bacteria and the EPS contributed to the bio-film function. In the EDS analysis, the elements C, O, P, S, K and Fe were detected in the EPS. Numerous indigenous bacteria of which size range between 1.19 to 1.42 ㎛ were attached along the cracks on the pyrite surface. These bacteria are able to actively select the sites from which is most ease to gain energy through oxidation. On the pyrite-leaching medium, the pH values were higher in the bacterial sample than the control sample, whereas the Eh values were lower in the bacteria sample than in the control sample. Because the indigenous acidophilic bacteria were capable of bioleaching the pyrite. The Zn content in the pyrite-leaching medium decreased with an increase in the pulp density.