Kinetic, Thermodynamic, adsorption and electrochemical studies for Corrosion Behaviour of Aluminium AA6063 Alloy in Ethanolic Extract of Lawsonia alba Lam. Leaves

Abstract

Corrosion behavior of Aluminium AA6063 alloy was tested in 0.5 N HCl in presence of various concentration of ethanolic extract of Lawsonia alba Lam. Leaves. The inhibition efficiency was evaluated by chemical and electrochemical methods. Inhibition efficiency was found to increase with increase in concentration of ethanolic extract of Lawsonia alba Lam. Leaves. Kinetic, thermodynamic and adsorption studies were made. Kinetic studies shows that the mechanism follows first order kinetics. Thermodynamic studies for the inhibitor-metal interactions clearly indicate that adsorption of ethanolic extract of Lawsonia alba Lam. Leaves extract on AA6063 in acid medium follows Langmuir adsorption isotherm. The nature of adsorption was evaluated as physical adsorption. The Potentiodynamic polarization results confirm that ethanolic extract of Lawsonia alba Lam. Leaves extract act as mixed inhibitor.