Theoretical and Experimental Study of a New Imidazo (1,2-a) Pyridine Derivative as a Corrosion Inhibitor for the Carbon Steel Surface in the Saline Media

Abstract

Newly synthesis derivative of imidazo (1,2-a) pyridine namely, 2-(4-Bromo-phenyl)-2,3-dihydro-imidazo[1,2-a] pyridine-3-yl methylene]- phenyl-amine (BDIPMA) was investigated as corrosion inhibitor for carbon steel in saline solution (3.5% NaCl) using potentiometric polarization measurements. Experimentally, the thermodynamic parameters obtained have supported a physical adsorption mechanism and the adsorption followed the Langmuir adsorption isotherm. Quantum mechanical method of the Density Functional Theory (DFT) of B3LYP with [6-311++G (2d, 2p)] level were used to calculate the optimized structure, chemical inhibition efficiency parameter (%IE) and physical properties in vacuum and two solvents (DMSO and H2O), all at the equilibrium geometry. The surface changes of the carbon steel were studied using SEM and AFM techniques.