Isolation and Cultivation of Acidithiobacillus ferrooxidans and Its Effects on Bioleaching of Phosphate Ore

A strain of Acidithiobacillus ferrooxidans that can be used effectively in the leaching of low grade phosphate ore was isolated from acid mine drainage from a coal mine in Anhui Province in China.Its characteristics of morphology and growth were studied.Through the investigation of the effects of different solid culture medium components on the isolation and purification of Acidthiobacillus ferrooxidans,the optimum isolation conditions were determined as:the concentration of Fe2+ in 9K solid culture medium was 4.5 g/L.A double-layer plate,with heterotrophic microbe Rhodotorula sp.spreading onto the bottom layer and chemoautotrophic bacterium At.f spreading onto the upper layer,was used.The influential factors including culture media,energy source materials and the addition of surfactant on the leaching of phosphate ore with the cultivated At.f were studied.Through preliminary experiments,up to 48% of phosphate in the ore was leached out using the isolated At.f strain.