Uranium bioleaching from low-grade carbonaceous-siliceous-argillaceous type uranium ore using an indigenous Acidithiobacillus ferrooxidans

Abstract

We evaluated the effectiveness of bioleaching uranium from a low-grade carbonaceous-siliceous-argillaceous type uranium ore using an indigenous iron-oxidizing bacteria, Acidithiobacillus ferrooxidans, isolated from local uranium ore. The effects of initial acidity, pulp density and ferrous ion concentration of the feed solution were investigated. The uranium (U3O8) content was 0.036% by weight. Using uranium ore acidified leachate as medium with initial ferrous ion concentrations of 3 g/L, pH 1.7 and pulp density of 20% as optimal conditions, the maximum rate of dissolved uranium recovery was 85.14%. This approach is thus, suitable for recovering uranium from low-grade CSA ore using bacterial leaching.