Temperature effects on the corrosion inhibition of carbon steel in 1N H3PO4 solution by methanolic extract of Euphorbia Falcata.L.

Abstract

Efficiency of methanolic extract of Euphorbia Falcata.L (MEEF.L) as corrosion inhibitor for carbon steel in 1N H₃PO₄ medium was investigated in the present study. Weight loss data obtained at  different temperatures are used to evaluate inhibition efficiency (IE%) and thermodynamic parameters such as heat of adsorption of the inhibitor on the metal surface, change in free energy of the reaction (ΔG), corrosion rate and energy of activation for corrosion reaction of mild steel (Ea). Langmuir’s adsorption isotherm was plotted to verify the nature of adsorption of the inhibitor on the metal surface.