[Difference in acclimation of Acidithiobacillus ferrooxidans by various substrates and its effect on coal desulfurization efficiency].

In this study, Acidithiobacillus ferrooxidans LX5 was cultured in 9K medium with pyrite and ferrous sulfate as the substrates. Results showed that the number of A. ferrooxidans LX5 acclimated by pyrite for 20 d was 3.0 x 10(7) cell/mL in the liquid, and the oxidation activity to pyrite was stronger. A. ferrooxidans LX5 cultured for 48 h was 1.0 x 10(8) cell/mL in medium with FeSO4. Extracellular polymeric substance (EPS) produced from A. ferrooxidans LX5 acclimated by pyrite was 2 395 microg/(10(10) cells) three times as much as that cultured with FeSO4. A high-sulfur coal desulfurization experiment were carried out with A. ferrooxidans LX5 domesticated respectively in medium with ferrous sulfate and pyrite. The results showed that the coal desulfurization rate was up to 72.4% after bioleaching for 13 d by A. ferrooxidans LX5 acclimated by pyrite, at the same time, the desulfurization rate was only 47.2% with A. ferrooxidans LX5 cultured with ferrous sulfate and reached 65.8% in 20 d. Therefore, the desulfurization efficiency can be improved of coal and shorten the desulfurization time when A. ferrooxidans LX5 acclimated with pyrite as the substrate.