Calculation of Uniform Corrosion Current Density of Iron in Hydrochloric Acid Solutions based on the Principle of Maximum Entropy Production Rate Applied to Literature Data

In this paper a new procedure for the calculation of uniform corrosion current density is presented. The procedure is based on the following criterion: corrosion current and extent of anodic and cathodic areas are such that the entropy production rate is maximum. Experimental data for the reaction Fe(s) + HCl(aq) = FeCl2(aq) + H2(g), taken from literature, are used to test the new model. A comparison between corrosion current density calculated from weight loss measurements and current density calculated from polarization curves by means of the proposed model is carried out. The proposed model provides a better agreement, between Tafel line extrapolation and gravimetric measurement, in comparison to the mixed potential theory usually adopted.