The Corrosion of Copper Metal in HCl Solutions and the effect of Molybdate and Chromate

Abstract

Dissolution characteristics of copper in hydrochloric acid medium and the effect of potassium chromate and sodium molybdate on the corrosion process have been studied using potentiodynamic technique, and Electro impedance spectroscopy (EIS). corrosion current density ( I corr) were obtained by Tafel extrapolation technique. Charge transfer resistance (R ct) was obtained from the electrochemical impedance spectroscopy (EIS). The corrosion rate was retarded in presence of sodium molybdate mainly because of the adsorption of the inhibitor on the electrode surface and it was found that the optimum concentration of this inhibitor in 1 M HCl was 0.008 M with an protection efficiency 79.17%, while the corrosion rate was accelerated in presence of potassium chromate.