Heterogeneous corrosion behaviour of carbon steel in water contaminated biodiesel

Biodiesel has been widely used as an additive to traditional fuel supplies, but the corrosion of metals used in biodiesel infrastructure is becoming an increasing concern. In this study, the influence of water contamination and corrosion behaviour of carbon steel in biodiesel, were characterized using the wire beam electrode (WBE) technique. In situ local current distributions among the electrodes showed a distinct corrosion pattern, with the anodes formed in the area that was exposed to water, and the cathodes formed along the water–biodiesel interface. The anodic current distribution showed a positive correlation with the biodiesel concentration gradient in water.