Bioleaching of antimony minerals by bacteria Acidithiobacillus Ferrooxidans and Desulfovibrio Desulfuricans

The objectives of this work were to evaluate the use of sulphate-reducing bacteria Desulfovibrio sp. and sulphur-oxidising bacteria Acidithiobacillus sp. for the leaching of gold-bearing antimony sulfide minerals. The basic metabolic process of Desulfovibrio sp. is the anaerobic reduction of sulphates to hydrogen sulphide, which can use for leaching antimony-bearing materials. The basic metabolic process of Acidithiobacillus sp. is the aerobic oxidation of sulphur in result of which may be used for the oxidation of sulphur from antimony sulphide minerals. Series of aerobic and anaerobic tests were studied in a fed batch reactor at 30°C. Samples of gold-bearing antimony sulphide minerals were kept in static and dynamic conditions. After 40 days the solid and liquid phase were analysed. Solubilized metals were determined using an atomic absorption spectrophotometer. Solid residues recovered by filtration were analysed by means of X-ray diffraction.