Inhibitive effect of diethylcarbamazine on the corrosion of mild steel in hydrochloric acid

Abstract

Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), weight loss measurements and atomic force microscopy techniques were used to investigate the inhibitory effect of diethylcarbamazine (DECM) on corrosion of mild steel in HCl solution. The inhibitor showed >90% inhibition efficiency at 5.01 × 10-4 M. Results obtained revealed that inhibition occurs through adsorption of inhibitor molecules on metal surface without modifying the mechanism of corrosion process. Potentiodynamic polarization studies suggested that it is a mixed type inhibitor, predominantly controls cathodic reaction. Activation parameters (Ea, Δ H and Δ S) and thermodynamic parameters (Δ Gadso, Δ Hadso and Δ Sadso) were calculated to investigate mechanism of inhibition. © 2009 Elsevier Ltd. All rights reserved.