Experimental and theoretical studies on the inhibition potentials of some derivatives of cyclopenta‐1,3‐diene for the corrosion of mild steel in HCl solutions

Abstract

AbstractThe inhibition of the corrosion of mild steel in HCl by some cyclopentadiene‐1,3‐diene derivatives, namely, 1‐(thiophen‐2‐yl)ethanone (2APT), 1‐(1H‐pyrrol‐2‐yl)ethanone (2AP), and (E)‐2‐(1‐hydrazonoethyl)‐1H‐pyrrole (2APH)), was studied experimentally using weight loss and hydrogen gas evolution measurements. The theoretical aspect was studied using the density functional theory and quantitative structure activity relation (QSAR) methods. The results obtained indicated that the studied compounds are good inhibitors for the corrosion of mild steel in HCl. The adsorption of the inhibitor on mild steel surface was found to be spontaneous, exothermic, and obeyed the Langmuir adsorption isotherm model. A good correlation was found between experimental inhibition efficiencies and some calculated quantum chemical parameters and also with the theoretical inhibition efficiencies obtained from QSAR modeling. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011