Inhibition of corrosion of mild steel in sulphuric acid medium by Calotropis procera

Purpose - The purpose of this paper is to evaluate the corrosion inhibition potential of Calotropis procera in sulphuric acid medium on mild steel with a view to developing green corrosion inhibitors. Design/methodology/approach - Extract of the C procera was studied for its corrosion inhibitive effect by weight loss, electrochemical, SEM and UV methods. Using weight loss measurement data, mechanism of inhibitive action is probed by fitting in adsorption isotherm. Findings - C. procera has been found to show significant corrosion inhibitive effect in sulphuric acid medium on mild steel. Inhibition is through adsorption of the phytoconstituents on mild steel following Tempkin adsorption isotherm. The results of ac impedance and polarization studies correlate well with the weight loss studies. Originality/value - The plant has been investigated for the first time for its corrosion inhibitive effect. The effect has been studied by proven methods. This green inhibitor can find use in the inhibition of corrosion in industries where mild steel is used as a material of choice for the fabrication of machinery.