Bioleaching of Pyrrhotite with Bacterial Adaptation and Biological Oxidation for Iron Recovery

The microbially mediated recovery of valuable metals contained in mining waste presents an economical alternative to conventional hydrometallurgical processes. In order investigate the effect bacterial adaptation and biological oxidation on bioleaching, bioleaching a pyrrhotite sample from mine waste, with indigenous bacteria existing acid drainage, was studied. were sub-cultured repeatedly for iron adaptation, Acidithiobacillus ferrooxidans identified as dominant member microbial consortium. point zero charge (PZC) sampled determined 3.0. performance by contact non-contact compared conducting under different initial pH (pHini) conditions (2.8 3.2). Negatively charged could be attached onto pyrrhotite, which has positive surface at lower pHini (2.8) than PZC (3.0). Bacteria attachment corrosion pits residues observed 2.8. Under bacteria-adapted conditions, leaching concentration Fe (44.2 mg/L) 2.8 2.1 times greater that (21.3 3.2. non-adapted extent not significantly between This attributed fact adapted more easily attach surfaces 2.8, allowing during experiments. We demonstrate here increase through oxidation.