FERROUS SULFATE OXIDATION USING THIOBACILLUS-FERROOXIDANS - A REVIEW

The ability of the chemolithotrophic bacterium Thiobacillus ferrooxida ns to oxidise ferrous sulphate has been exploited in the process of bi oleaching, treatment of acidic mine drainage and removal of H2S from s our gases. Over the years, much attention has been paid to this organi sm and the process it catalyses. Unfortunately, inconsistent and ambig uous results have been reported in the literature. Therefore, further studies need to be undertaken in order to verify the optimal pH and te mperature ranges of 2.0-2.3 and 30-33 degrees C respectively and the o ptimal levels of O-2 and CO2 as well as the values of the basic kineti c parameters and the effect of substrate and product inhibition. On th e process side, the work has mainly been aimed at improving the rate o f ferrous iron oxidation and numerous immobilisation matrices and bior eactor systems have been tested.