Electrochemical Investigation of the Inhibitive Effect of a New Synthetic Schiff-base on the Corrosion of Mild Steel in Acidic Media
In this work the inhibition effect of a new synthetic Schiff base on mild steel corrosion in 1M HCl and 0.5 M H2SO4 was investigated using various electrochemical techniques (potentiodynamic polarization , AC impedance) and weight loss measurements. These measurements revealed that this Schiff base inhibited the corrosion of mild steel in both media and was a mixed-type inhibitor. This inhibitor was adsorbed on the mild steel surface according to a Langmuir isotherm adsorption model. In both media, inhibition efficiency increased with increasing Schiff base concentration. The values of free energy of adsorption were calculated to investigate the mechanism of corrosion inhibition. Scanning electron microscopy (SEM) observation confirmed the existence of an absorbed protective film on the metal surface.
Key Words: Schiff-base, mild steel, AC impedance, corrosion
inhibition, Langmuir isotherm.