Exploration of modified β-cyclodextrin compounds as enhanced eco-friendly and easily accessible corrosion inhibitors for carbon steel in hydrochloric acid

Abstract

β-CD was esterified independently with two distinct ionic liquids to evaluate their potential as corrosion inhibitors for carbon steel in a 1.0 M HCl solution. Experimental and computational methods were used to assess the inhibitors’ efficiency regarding temperature and concentration effects and to elucidate the adsorption mechanism. Both inhibitors acted as barriers, with a maximum inhibition efficiency of about 94 % at 200 ppm. There was a direct relationship between the inhibitor's concentration and their efficiency, while increasing the temperature reduced the inhibitors’ effectiveness. The thermodynamic and kinetic parameters were evaluated and studied. DFT calculation revealed the electronic structure and reactivity of the inhibitors. Molecular dynamic simulation provided insight into the optimal configuration and binding energies of inhibitors on the Fe (110) surface.