INFULUENCE OF pH ON BIOLEACHING OF COPPER AND ZINC FROM COMPLEX SULPHIDE CONCENTRATE USING THIOBACILLUS FERROOXIDANS

摘要

pH plays an important role on the growth of Thiobacillus ferrooxidans and on their ability to leach toxic heavy metals. Present work relates to the growth of T. ferrooxidans at different pH in the presence and absence of substrate (complex sulphide concentrate) in the medium. The cell yield was sound to be maximum at pH 1.5 in the presence and absence of substrate in the medium. Copper and zinc extraction were found to be 45.7 percent and 90.5 percent respectively at a pH of 1.5. With increase in bacterial populations, the leaching rate was also increased.