Microbial Effects on Geochemical Behavior of Antimony and Synthesis of Antimony Trioxide

The effects of indigenous Sb-resistant bacteria isolated from Sb-contaminated soil on behavior of dissolved Sb(III) were experimentally investigated under aerobic condition. Two indigenous bacteria, PS2 (Pseudomonas nitroreducens) and PS3 (Variovorax paradoxus) were isolated from the soil containing 2,584 mg/kg of Sb. These bacteria decreased the concentration of dissolved Sb(III) and transformed Sb(III) to white orthorhombic Sb2O3 nanomaterial when 1 mM organic material supplied. There was no change of Sb(III) concentration over time in the case of supply with 5 mM organic material. The precipitated nanostructure of Sb2O3 showed highly similar morphology and mineralogical characteristics with the 'nanobelt bundles' which were previously manufactured by complicated chemical processes, implying applicability to optoelectronic industries. The results indicated that microbial transformation of toxic Sb(III) to Sb2O3 nanooxide may decrease toxicity and mobility of Sb in natural settings and be applied for industrial synthesis of Sb2O3 nanostructure.