Distinguishing two different microbiologically influenced corrosion (MIC) mechanisms using an electron mediator and hydrogen evolution detection

Abstract

Carbon steel MIC (microbiologically influenced corrosion) and copper MIC by Desulfovibrio vulgaris (a sulfate reducing bacterium) were shown to behave very differently. Carbon steel MIC was accelerated with an 84 % weight loss increase by 20 ppm (w/w) riboflavin (an electron mediator) while Cu MIC was not. This was because the former belongs to extracellular electron transfer (EET)-MIC while the latter metabolite (M)-MIC. Cu MIC by biogenic H2S yielded a large amount of H2. This work proved that an electron mediator can distinguish EET-MIC from M-MIC, and H2 gas detection is very sensitive in identifying M-MIC with H2 evolution.