Kinetics and mechanism of uranium bioleaching from a low grade indian ore

Uranium leaching mechanism by biogenic ferric ions from the enriched culture of Acidithiobacillus ferrooxidans from a low grade Indian uranium ore has been elucidated. Biodissolution of 98% uranium was obtained at 20% (w/v) pulp density, 1.7 pH and 35°C temperature using <76 µm particles in 40 days under the optimized conditions. Iron (III) generated through the bacterial oxidation of pyrite and chemical dissolution of magnetite present in the ore under acidic condition, has a bearing on the bioleaching of uranium. The kinetics of uranium dissolution by bacteria followed the chemical control model which was corroborated by XRD and SEM studies.