Experimental and Theoretical Investigations of  Lansoprazole As Inhibitor for Mild Steel Corrosion in  1M Hydrochloric Acid

G. Karthik; P. Karuppasamy; M. Sundaravadivelu

Volume : III, Issue : X, October - 2013

Experimental and Theoretical Investigations of Lansoprazole As Inhibitor for Mild Steel Corrosion in 1M Hydrochloric Acid

G. Karthik, P. Karuppasamy, M. Sundaravadivelu

Abstract :

The inhibition effect of lansoprazole drug (LP) as an inhibitor on the corrosion of mild steel (MS) in 1M HCl has been studied by electrochemical impedance spectroscopy (EIS) and Tafel polarization. Morphology of the MS specimens was examined using scanning electron microscopy (SEM) in presence and absence of inhibitor. The results show that LP is a good inhibitor and the inhibition efficiency (IE %) increases with the inhibitor concentration. Polarization curves show that LP is a mixed type inhibitor in hydrochloric acid solution. Quantum chemical calculations were performed using the density functional theory to find out whether a clear link exists between the inhibitive effect of the inhibitor and the electronic properties of its main constituents. The results obtained from the Tafel polarizations and EIS are in good agreement with theoretical calculation.