Corrosion of EH40 steel enhanced by exogenous electron intermediaries in seawater containing Methanococcus maripaludis

The effects of exogenous electron intermediaries, i.e., 9,10-anthraquinone-2-carboxylic acid (AQC), neutral red and thionine, on EH40 steel corrosion were investigated in seawater with Methanococcus maripaludis. Results showed that M. maripaludis can acquire electrons from EH40 steel through indirect electron transfer facilitated by these three exogenous electron intermediaries, thereby enhancing the charge transfer during corrosion process. This promotion effect on EH40 steel corrosion follows an order: AQC > neutral red > thionine, which correlates with their respective charge transfer capacities. The introduction of exogenous electron intermediaries enhances pitting corrosion of EH40 steel induced by M. maripaludis.