Discussion on "Electrochemistry of CO2 corrosion of mild steel: Effect of CO2 on iron dissolution reaction" by A. Kahyarian, B. Brown, S. Nesic, [Corros. Seri. 129 (2017) 146-151]

This discussion presents an analysis of the recent paper by Kahyarian, Brown and Nesic published in this Journal Kahyarian et al. (2017). Indeed, the paper claims an anodic participation of CO2 in the iron dissolution mechanism, not detected by our work also published in this same journal Almeida et al. (2017). The anodic role was, however, only limited to the analysis of Tafel slopes behaviour. This is what was typically done in the early works of iron dissolution in acid media during the 1960's, so that a discussion about this methodology based on the progress of the electrochemistry that has been developed since the 1980's is absolutely necessary.