New insights on the role of CO2 in the mechanism of carbon steel corrosion

CO2 corrosion is an important process affecting oil and gas industries. Understanding the role of CO2 in the mechanism of carbon steel dissolution may contribute to better predict corrosion rate. Impedance, local pH and weight loss tests were measured using X65 carbon steel at pH 4 in the presence and absence of CO2, including high CO2 pressure experimental conditions. The results did not evidence a direct reaction of CO2 on the free iron surface.