Inhibition of mild steel corrosion by Rabeprazole sulfide

The inhibition effect of Rabeprazole sulfide (2-[[4-(3-methoxypropoxy)-3-methylpyridine-2-yl]-methylthio]-1H-benzimidazole) (RS) on the corrosion behavior of mild steel in 0.5 M H2SO4 solution was studied by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. Polarization measurements indicate that RS act as a mixed type inhibitor. The adsorption of RS on the mild steel surface follow Langmuir adsorption isotherm model and zero order kinetics. The thermodynamic parameters governing the adsorption process were determined and discussed. Also, quantum chemical parameters were calculated to provide further insight into the mechanism of inhibition action of RS.

► Rabeprazole sulfide showed good inhibition efficiency for mild steel in 0.5 M H2SO4.
► It acts as mixed type inhibitor.
► Follows Langmuir adsorption isotherm and zero order kinetics.
► Evaluation by chemical, electrochemical and quantum chemical methods.