2-Methyl Imidazole as a Corrosion Inhibitor for Mild Steel in Acid Medium

Abstract

The inhibition effect of 2-methyl imidazole on the corrosion of mild steel in acid medium has been studied by mass loss and polarization techniques between 303 and 333 K. The inhibition efficiency increased with increase in concentration of inhibitor and temperature from 303-318 K for both acids. But at higher temperature (333 K) the inhibition efficiency decreased. The corrosion rate increased with increase in temperature and decreased with increase in concentration of inhibitor compared to blank. The adsorption of this compound on the mild steel surface has been found to obey Temkin's adsorption isotherm. Potentiostatic polarization results reveal that 2-methyl imidazole is a mixed type inhibitor. The values of activation energy (E_a) and free energy of adsorption (ΔG_ads) were also calculated.