Synthesis, characterization and the inhibition activity of a new alpha-aminophosphonic derivative on the corrosion of XC48 carbon steel in 0.5 M H2SO4: Experimental and theoretical studies

摘要

A new aminophosphonic derivative was synthesized and characterized by UV-vis, IR, H-1 NMR, C-13 NMR and MS spectroscopic methods. Its inhibitive action on the carbon steel corrosion in a 0.5 M H2SO4 solution was studied by polarization curves and electrochemical impedance spectroscopy (EIS). The results indicated that the synthesized compound is an efficient mixed-type inhibitor and its inhibition efficiency increased with increasing the inhibitor concentration. The adsorption of the inhibitor on the carbon steel surface obeys Langmuir isotherm and the thermodynamic parameters were obtained. The surfaces of carbon steel after exposing to test solutions were examined by atomic force microscopy (AFM). The quantum chemical parameters were calculated in gas and aqueous phases using the density functional method (DFT). The interaction between the inhibitor and Fe (100) surface were performed by molecular dynamic simulations. (C) 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.