Corrosion behaviour of an aluminized nickel coating in a carbon dioxide capture process using aqueous monoethanolamine

Carbon steel A106 with an aluminized Ni coating was tested in a 5 mol/l (M) monoethanolamine (MEA) with a carbon loading of 0.2 mol/mol MEA at 80 °C using polarization resistance, Tafel, and electrochemical impedance spectroscopy (EIS) techniques. Surface morphology and elemental line profile of the coating were examined before and after a 900 °C heat-treatment in atmosphere environment. X-ray diffraction (XRD) results showed that the coating surface constitutes transformed from Ni₂Al₃ to Al-rich NiAl after heat-treatment. The electrochemical results show that the heat-treated coating displays outstanding corrosion performance with the conditions tested.