Electrochemical Investigation of The Effect of Penicillin G Benzathine as a Green Corrosion Inhibitor For Mild Steel

In this paper, the effect of penicillin G benzathine (PGB) drug as a green corrosion inhibitor on mild steel in 1.0 M hydrochloric acid solution has been investigated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The inhibition efficiency (IE) was found to increase with increasing inhibitor concentration. Potentiodynamic polarization measurements indicated that PGB is a mixed type inhibitor. The results of potentiodynamic polarization and EIS measurements demonstrated that the adsorption of PGB on mild steel in 1.0 M HCl follows Langmuir isotherm. The calculated values of free energy indicated that both physical and chemical adsorption take place. The IE values obtained from EIS measurements show a reasonable agreement with those obtained from potentiodynamic polarization method.