Jatropha Tanjorensis Leaf Extract as an Environmentally Friendly Mild Steel Corrosion Inhibitor in Acidic Medium

Abstract : The inhibition of the corrosion of mild steel in 1 M H2SO4 solution by Jatropha tanjorensis leaf extract (JTLE) has been studied using weight loss and hydrogen evolution techniques. The results obtained reveal that JTLE effectively inhibited the corrosion of mild steel in H2SO4 solution. The highest inhibition efficiency of 89.73% occurred at 5.0 g/L JTLE concentration at 333K by weight loss measurements. Inhibition efficiency was found to increase with increase in JTLE concentration and temperature. Chemical adsorption has been proposed for the adsorption of JTLE onto mild steel surface. The positive values of enthalpy of adsorption (ΔH°ads) reveal the endothermic nature while the negative values of Gibb’s free energy of adsorption (ΔG°ads) indicate the spontaneous nature of adsorption of JTLE onto mild steel surface. The adsorption of JTLE onto mild steel surface obeyed the Langmiur Adsorption Isotherm.