Extraction of Copper from Malanjkhand Low-Grade Ore by Bacillus stearothermophilus

Thermophilic bacteria are actively prevalent in hot water springs. Their potential to grow and sustain at higher temperatures makes them exceptional compare to other microorganism. The present study was initiated to isolate, identify and determine the feasibility of extraction of copper using thermophilic heterotrophic bacterial strain. Bacillus stearothermophilus is a thermophilic heterotrophic bacterium isolated from hot water spring, Atri, Orissa, India. This bacterium was adapted to low-grade chalcopyrite ore and its efficiency to solubilize copper from Malanjkhand low-grade ore was determined. The low-grade copper ore contains 0.27% Cu, in which the major copper-bearing mineral is chalcopyrite associated with other minerals present as minor phase. Variation in parameters such as pulp-density and temperatures were studied. After 30 days of incubation, it was found that Bacillus stearothermophilus solubilize copper up to 81.25% at pH 6.8 at 60°C.