Table of Contents
ISRN Corrosion
Volume 2012, Article ID 842836, 9 pages
Research Article

3-Formylindole-4-aminobenzoic Acid: A Potential Corrosion Inhibitor for Mild Steel and Copper in Hydrochloric Acid Media

Research Division, Department of Chemistry, St. Thomas' College, University of Calicut, Thrissur 680001, India

Received 19 September 2012; Accepted 2 October 2012

Academic Editors: C. Gu, A. Hermann, C.-H. Hsu, G. Marginean, and C. Valentini

Copyright © 2012 Aby Paul et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The corrosion inhibition efficiencies of Schiff base 3-formylindole-4-aminobenzoic acid (3FI4ABA) on mild steel (MS) and copper in 1.0 M HCl solution have been investigated using weight loss measurements, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization studies. The results show that inhibition efficiencies on both metals increase with increasing the concentration of the inhibitor. 3FI4ABA exhibited comparatively good inhibition towards mild steel in HCl medium even at low concentrations. The adsorption of inhibitor on the surfaces of the corroding metal mild steel and copper obeys the Langmuir isotherm. Polarization studies revealed that 3FI4ABA acts as a mixed-type inhibitor. Thermodynamic parameters ( , ) were calculated using the Langmuir adsorption isotherm.