Effects of iron-reducing bacteria on carbon steel corrosion induced by thermophilic sulfate-reducing consortia.
Four thermophilic bacterial species, including the iron-reducing bacterium Geobacillus sp. G2 and the sulfate-reducing bacterium Desulfotomaculum sp. SRB-M, were employed to integrate a bacterial consortium. A second consortium was integrated with the same bacteria, except for Geobacillus sp. G2. Carbon steel coupons were subjected to batch cultures of both consortia. The corrosion induced by the complete consortium was 10 times higher than that induced by the second consortium, and the ferrous ion concentration was consistently higher in iron-reducing consortia. Scanning electronic microscopy analysis of the carbon steel surface showed mineral films colonized by bacteria. The complete consortium caused profuse fracturing of the mineral film, whereas the non-iron-reducing consortium did not generate fractures. These data show that the iron-reducing activity of Geobacillus sp. G2 promotes fracturing of mineral films, thereby increasing steel corrosion.
Chemical and Biology Research Institute, Michoacan University of San Nicolas of Hidalgo (UMSNH), 58030 Michoacan, Mexico.
Eduardo
E
Valencia-Cantero
Juan José
JJ
Peña-Cabriales
D002244:Carbon / Q000378:metabolism*; D003343:Corrosion; D007501:Iron / Q000378:metabolism*; D059013:Microbial Consortia; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D013232:Steel; D013431:Sulfates / Q000378:metabolism*; D013499:Surface Properties
D013431:Sulfates; D013232:Steel; D002244:Carbon; D007501:Iron