Effect of salinity and acidity on bioleaching activity of mesophilic and extremely thermophilic bacteria

来源期刊：中国有色金属学报(英文版)2008年第3期

论文作者：H. DEVECI M. A. JORDAN N. POWELL I. ALP

文章页码：714 - 721

Key words：bacteria; bioleaching; salinity; pH; sulphide

Abstract: The effects of bacterial strain, salinity and pH on the bioleaching of a complex ore using mesophilic and extremely thermophilic bacteria were investigated and the statistical analysis of the results was performed using ERGUN’s test. The extreme thermophiles were shown to display superior kinetics of dissolution of zinc compared with the mesophiles as confirmed by the statistical analysis. Bioleaching performance of the extreme thermophiles is found to improve in response to the increase in acidity (pH from 2.0 to 1.0) whilst the activity of the mesophiles is adversely affected by decreasing pH. Statistical analysis of the bioleaching data indicates that the effect of pH is insignificant in the range of pH 1.0-1.2 for the extreme thermophiles and pH 1.4-2.0 for the mesophiles. Salinity is shown to have a suppressing effect on the mesophiles. However, the extreme thermophiles appear to be halophilic in character as they could operate efficiently under saline conditions (1%-4%Cl- (w/v)).