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iron-oxidizing bacteria

1. n. [Enhanced Oil Recovery]
Aerobic bacteria that convert iron from the ferrous [Fe+2] to the ferric [Fe+3] state and produce ferric hydroxide [Fe(OH)3], which is a highly insoluble by-product that will damage the formation. Iron-oxidizing bacteria also produce some corrosion, but they are considered harmful mainly because they cover sulfate-reducing bacteria colonies and protect them from attack with bactericides.