A comprehensive study on the impact of Fe ion concentration on carbon steel corrosion in a CO2 environment

In this work, the corrosion behaviour of steel wires in solutions containing different concentrations of Fe2+ was investigated, while the evolution of pH was monitored in-situ and changes of the Fe2+ concentration were monitored ex-situ. Characterization of the corrosion scales was performed by using microscopic and diffraction techniques. Scale analysis revealed that the passivation of samples, exposed to initially highly Fe2+ super-saturated solution, occurred when a formation of a double layer took place, resulting in 30 times lower corrosion rate compared to samples tested in solutions without initial Fe2+.