Experimental and theoretical study on corrosion inhibition of oxime compounds for aluminium in HCl solution

• Three oxime compounds are new good inhibitors for aluminium in HCl solution.
• Inhibition efficiency follows the order: CO > BO > AO.
• The adsorption of oxime inhibitor obeys Langmuir adsorption isotherm.
• There is a correlation of quantum chemical parameters with the inhibition action.
• Oxime molecules adsorb on the Al (1 1 1) surface in the nearly flat manner.

The inhibition effect of three oxime compounds of acetone oxime (AO), 2-butanone oxime (BO) and cyclohexanone oxime (CO) on the corrosion of aluminium in HCl solution was studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), quantum chemical calculation and molecular dynamics (MD) simulation methods. The results show that all oxime compounds are good inhibitors, and inhibition efficiency follows the order: CO > BO > AO. The adsorption of each inhibitor on aluminium surface obeys Langmuir adsorption isotherm. All these oxime compounds act as cathodic inhibitors. The probable inhibitive mechanism is proposed from the viewpoint of adsorption theory.