The corrosion inhibition study of Al –Pure By p-Anisidine -N-Benzylidene Schiff base in HCl solution.

Abstract

In this investigation, the inhibition effect of p-Anisidine-N-Benzylidene (p-AnNB) on the corrosion of Al-Pure in 1.0 M HCl has been studied by weight loss, galvanostatic polarization, and electrochemical impedance spectroscopy (EIS) measurements. It was found from the polarization curves that the used Schiff base is of mixed type inhibitor with predominant effect on cathode. The changes in polarization and impedance parameters values (Icorr, Rct and Cdl) obtained indicate that the adsorbed protective film grows with increasing concentration of inhibitor. The adsorption of used compound on Al-Pure found to obey langmuir isotherm. Some thermodynamic parameters (ΔGads and Qads) and activation energy (Ea) were calculated to elaborate the mechanism of corrosion inhibition. The Schiff base used for investigation is an excellent inhibitor for Al-Pure in 1.0 M HCl. The optimum concentration of this inhibitor is 0.5 % with around 99.78 % inhibition efficiency. The obtained results from various techniques are in good agreement.