A green Approach:A corrosion inhibition of mild steel by adhatoda vasica plant extract in 0.5 M H2SO4

The extract of adhatoda vasica in aqueous 0.5 M H2SO4 was systematically investigated to ascertain its inhibitory effect on corrosion of mild steel and its mechanism of the inhibition by weight loss method, potentiodynamics polarisation technique and electrochemical impedance spectroscopy (EIS). The inhibition efficiency of adhatoda vasica on corrosion of mild steel in 0.5 M H2SO4 solution increases on increasing in its concentration and decreases with rise in temperature. Potentiodynamic Polarization measurement show that adhatoda vasica acts as mixed type inhibitor. The increase in activation energies of corrosion process in presence of the extract indicates that adhatoa vasica extract retarded the rate of corrosion of mild steel in 0.5 M H2SO4 solution. The nature of adsorption of the extract on mild steel surface was in conformity with Langmuir isotherm. The result of EIS was correlating with the result of polarization measurement. Scanningelectron microscopy (SEM) study confirmed that the inhibition of corrosion of mild steel is through adsorption of the extract molecules on surface of metal