UTILIZATION OF METAL BEARING INDUSTRIAL WASTE MATERIALS BY MICROBIOLOGICAL LEACHING

Abstract

Chemoautotrophic sulphur-bacteria were isolated from mine drainage waters /Th. ferrooxidans/, which are able to oxidize the ferrous-iron into ferric-iron in biocatalytic way in a heavy acidic medium. These bacteria were adapted to high metal especially to high iron, aluminium and sodium concentrations. The ferric-sulphate produced by the bacterial oxidation is a strong leaching agent. The optimal parameters were determined under which the acidic ferric-sulphate bearing solution is favourable from the point of view of practical utilization. During the biological oxidation process a part of dissolved iron precipitated in form of ferric-hydroxide which is also utilizable material.