GENERAL KNOWLEDGE

Detailed explanation-1: -Finally, leaching bacteria (Acidithiobacillus caldus and Leptospirillum ferriphilum) are proved to boost copper extraction from covellite by transforming Fe2+ into Fe3+ and eliminating surface elemental sulfur passivation.

Detailed explanation-2: -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.

Detailed explanation-3: -Bacillus is an important bacterial genus for bioremediation of heavy metals in different heavy metal contaminated areas (13, 16). In general, the isolates from the copper mining area showed stronger capacity for copper biosorption.

Detailed explanation-4: -Copper for its low-grade ores is majorly extracted by making the usage of the processes of hydrometallurgy. Moreover, the extraction of copper is majorly done by the process of leaching which relates to the use of bacteria. These bacteria leach out the ore and thereby extract copper from the metal compounds.

Detailed explanation-5: -The role of Thiobacillus ferrooxidans in bacterial leaching of mineral sulfides is controversial. Much of the controversy is due to the fact that the solution conditions, especially the concentrations of ferric and ferrous ions, change during experiments.