Electrochemical study of corrosion behaviour of carbon steel A106 and stainless steel 304 in aqueous monoethanolamine

Corrosion behaviour of carbon steel A106 and stainless steel 304 (SS304) in aqueous monoethanolamine was studied by performing electrochemical polarisation experiments. Potentiodynamic curves were studied and compared under conditions with different temperatures, carbon loading and O-2 percentage in purging gases. It was found that corrosion of A106 and SS304 was promoted under conditions with higher temperature. While the presence of O2 speeds the corrosion of A106, it has a negligible impact on SS304 at 80 degrees C and lowers the corrosion rate at 40 degrees C. Corrosion rates and other important parameters were calculated based on the electrochemical curves for A106. Sample surfaces after tests were examined by scanning electron microscopy and energy dispersive spectroscopy. Mechanisms involved in iron dissolution and passivation from oxide films were discussed.