Role of water, acetic acid and chloride on corrosion and pitting behaviour of carbon steel in fuel-grade ethanol

The role of water, acetic acid, chloride, and oxygen level in corrosion and pitting behaviour of carbon steel in simulated fuel-grade ethanol (SFGE) was investigated. In the absence of the supporting electrolyte, modified cell geometry enabled us to conduct the electrochemical measurement in low-conductivity ethanolic solutions. Results have shown that the water in the SFGE strongly influences the surface film stability and interface electrochemistry in ethanolic environments. The increase in the water concentration induces pitting and metal loss. Dissolved chlorides and higher acidity promote the pit initiation and growth. Alkaline condition inhibits both localized and uniform corrosion.