Electrochemical interactions of biofilms with metal surfaces

Two mechanisms of microbially influenced corrosion (MIC) are discussed and compared: corrosion modified by the presence of (1) sulfate-reducing bacteria (SRB) and (2) manganese-oxidizing bacteria (MOB). It is demonstrated that the nature of MIC in both cases depends on the nature of inorganic materials precipitated at the metal surface, iron sulfides and manganese oxides. Those materials are electrochemically active and, therefore, modify the electrochemical processes naturally occurring at the metal-solution interface. Some of these modifications may lead to accelerated corrosion.