Thiobacillus ferroxidans

F. ferro-oxidants is capable of accelerating the oxidation of pyritic (FeSj) deposits at acid pH values. It is usually found in association with Thio-bacillus and was known as Thiobacillus ferroxidans before the distinction between the two organisms was appreciated. It is responsible for pollution problems arising from acid waters in gold and bituminous coal mines such waters are corrosive to pumping machinery and mining installations (see Fig. 2.20). 

In the leaching process, bacteria such as Thiobacillus ferroxidans and those belonging to the Sulfolobus genera, play a major role in the oxidation reactions at moderate and higher temperatures respectively. The oxidation of sulfides by bacteria is typified by the reactions of pyrite, a common accessory mineral in primary copper ore bodies this reaction can be considered to proceed through two stages ... 

Chandra, D. Roy, P. Mishra, A.K., et al., Removal of Sulphur From Coal by Thiobacillus Ferroxidans and by Mixed Acidophilic Bacteria Present in Coal. Fuel, 1979. 59(4) pp. 249-252. 

Tc(VI) 43 D. radiodurans RT G. sulfurreducens G. metallireducens D. desulfuricans Thiobacillus thiooxidans Thiobacillus ferroxidans Rhodobacter shpaeroides Paracoccus denitrifleans Fredrickson et al. (2000) Lloyd et al. (2000) Lloyd et al. (2000) Lloyd et al. (1999) Lyalikova and Khizhnyak (1996) Lyalikova and Khizhnyak (1996) Lloyd et al. (2000) Lloyd et al. (2000)... 

Mandl M, Macholan L (1990) Membrane biosensor for the determination of iron (II, III) based on immobilized ceils of Thiobacillus ferroxidans. Folia Microbiol 35 363-... 

Espejo, R. T. and P. Romero. 1987. Growth of Thiobacillus ferroxidans on elemental sulfur. Appl. Environ. Microbial. 53 1907-1912. 

Microbes can control the local geochemical environment of actinides and alfect their solubility and transport. Francis et al. (1991) report that oxidation is the predominant mechanism of dissolution of UO2 from uranium ores. The dominant oxidant is not molecular oxygen but Fe(III) produced by oxidation of Fe(II) in pyrite in the ore by the bacteria Thiobacillus ferroxidans. The Fe(III) oxidizes the UO2 to UOl. The rate of bacterial catalysis is a function of a number of environmental parameters including temperature, pH, TDS, fo2, and other factors important to microbial ecology. The oxidation rate of pyrite may be increased by five to six orders of magnitude due to the catalytic activity of microbes such as Thiobacillus ferroxidans (Abdelouas et al., 1999). 

Thiobacillus ferroxidans Chromatium vinosum A Chromatium vinosum L... 

After these soils are drained, pyrite is oxidized to ferric hydroxide resulting in severe acidity to pH less than 2. The bacteria involved in oxidizing FeS2 are Thiobacillus ferroxidans and... 

S. M. Beloglazov, A. N. Charoshavin, Corrosion behavior of steel in coal mining waters in the presence of thiobacillus thioox-idans and thiobacillus ferroxidans. Proceedings of the 3rd International EFC Workshop, The European Federation of Corrosion by the Institute ofMaterial, 1995, pp. 398-404. 

Under appropriate conditions, over 90% of the pyritic sulfur from coals can be removed by the mesophilic sulfur-oxidizing autotrophic bacteria Thiobacillus ferroxidans and T. thiooxidans, but these bacteria were incapable of removing organic sulfur (Khalid et al., 1989,1990a,b Bhattacharyya et al., 1990 Huffman et al., 1990). However, the thermophilic archaebacterium Sulfolobus brier-layi was able to remove over 95% of the pyritic sulfur and over 30% of the organic sulfur from the untreated coal when the cells of S. brierleyi were acclimatized. The aerobic biosolubilization of low-rank coal to polar water-soluble products has been demonstrated (Scott et al., 1986 Cohen et al., 1987 Pyne et al., 1987 Wilson et al., 1987). 

Schrenk M. O., Edwards K. J., Goodman R. M., Hamers R. J., and Banfield J. F. (1998) Distribution of Thiobacillus ferrooxidans and Leptospirillum ferroxidans implications for generation of acid mine drainage. Science 279, 1519-1522. 

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