The Role of Oxygen in Anaerobic Microbiologically Influenced Marine Corrosion

The relationship between oxygen and microbiologically influenced corrosion (MIC) resulting from obligate anaerobic microbial processes is complex. Most reported cases of MIC of carbon steel and copper alloys in marine environments are caused by sulphate-reducing bacteria (SRB) with some dissolved oxygen in the bulk medium. Yet most laboratory experiments with SRB are conducted in the absolute absence of oxygen. The presence of oxygen can determine the rate and extent of corrosion resulting from obligate anaerobic microbial processes. Furthermore, the concentration of oxygen and the manner in which it is removed can affect experimental results. The specific coupled reactions for which oxygen is the final electron acceptor can vary. The role of oxygen in anaerobic MIC in both field and laboratory studies will be reviewed with an emphasis on SRB.