Bio-Hydrometallurgy for Extraction of Nonferrous Metals

The advent of microbial leaching process has opened scope for supplementing the availability of different non-ferrous metals globally, and has made the exploitation of poor grade and discarded ores/tailings, refractory ores, dirty concentrates and complex resources possible for metal recovery. The importance of various types of micro organisms has been recognised in the origin of minerals and metals beneath earth crust and in dissolution of various sulfidic and oxidic ores and concentrates. Since over a decade, Acidithiobacillus ferrooxidans has been commercially exploited in recovery of copper and uranium from ores, and gold and silver from refractory sulfide / arsenopyrite concentrates. Biotechnology is poised to have an explicit role in mineral processing in the next millennium