比较了嗜酸自养菌Acidithiobacillus ferrooxidans、嗜酸异养菌Acidiphilium cryptum、At. ferrooxidans和A. cryptum的混合菌在9K基体盐培养基中对黄铁矿的生物浸出以及磷矿的生物溶解。结果表明，虽然A. cryptum自身不能氧化黄铁矿和溶解磷矿，但能有效促进 At. ferrooxidans对黄铁矿的生物浸出以及磷矿的生物溶解。这种促进效应可通过A. cryptum促进At. ferrooxidans生物浸出黄铁矿体系中pH的降低以及氧化还原电位、总铁浓度和浮游细菌数目的升高的实验结果来证明。At. ferrooxidans和A. cryptum的混合菌液在30°C条件下溶解磷矿时可最大程度地释放其中的可溶性磷。矿浆浓度大于3%时会给At. ferrooxidans和A. cryptum的混合菌液释放可溶性磷带来不利影响。在9K基体盐培养基中添加黄铁矿对At. ferrooxidans和A. cryptum的混合菌液溶解磷矿是很有必要的，且磷矿和黄铁矿的质量比为1：2或1：3时可溶性磷浸出率较高。%The bioleaching of pyrite and biosolubilization of rock phosphate (RP) in 9K basal salts medium were compared by the following strains of an autotrophic acidophilic bacterium, Acidithiobacillus ferrooxidans, a heterotrophic acidophilic bacterium, Acidiphilium cryptum, and mixed culture of At. ferrooxidans and A. cryptum. The results show that A. cryptum is effective in enhancing the bioleaching of pyrite and biosolubilization of RP in the presence of At. ferrooxidans, although it could not oxidize pyrite and solubilize RP by itself. This effect is demonstrated experimentally that A. cryptum enhances a decrease in pH and an increase in redox potential, concentration of total soluble iron and planktonic part bacterial number in the broth during pyrite bioleaching processes by At. ferrooxidans. The mixed culture of At. ferrooxidans and A. cryptum leads to the most extensive soluble phosphate released at 30 °C. Pulp density exceeding 3% is shown to adversely influence the release of soluble phosphate by the consortium of At. ferrooxidans and A. cryptum. It is essential to add pyrite to the 9K basal salts medium for the biosolubilization of RP by the mixed culture of At. ferrooxidans and A. cryptum, and the percentage of soluble phosphate released is the greatest when the mass ratio of RP to pyrite is 1:2 or 1:3.
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