The Investigation of the Corrosion Inhibition Efficiency of Aqueous extract of Vernomia Amygdalina for Mild Steel In Various Concentrations of HCl

Abstract

 The corrosion inhibition potential of Vernomia amygdalona (VA) was investigated using different concentrations of aqueous extract of VA leaves (20 to 140 ppm), which was extracted by the cold process. Gravimetric analysis was carried out to investigate the effect of acid strength (0.4 to 2.0 M HCl), extract concentration and time on the inhibition efficiency of the VA extract. The results obtained showed a higher tendency for the inhibition efficiency to increase with the concentration of the extract but decrease with an increase in the period of contact. Adsorption isotherm fitness based on the Langmuir, Freundlich and Temkin models showed strong correlation coefficients. Physical adsorption. The evaluated values of the free energy of adsorption were below -20 kJ/mol and therefore supported the mechanism of physical adsorption.