Coriandrum Sativum.L Seeds Extract as a Novel Green Corrosion Inhibitor for Mild Steel in 1.0 M Hydrochloric and 0.5 M Sulfuric Solutions

The comparative study of the inhibition and adsorption properties of extract of Coriandrum Sativum seeds (CSE) as a new eco-friendly corrosion inhibition in 1.0 M hydrochloric and 0.5 M sulfuric solutions was investigated using several methods such as polarization curves, Bode plots, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). All results demonstrated that CSE suppressed the corrosion reaction in both acids medium (93.7% in 1.0 M HCl, 96.7% in 0.5 M H2SO4). Adsorption characteristics of the extract were approximated by various adsorption isotherm models (Langmuir, Freundlich and Temkin) and were in a good agreement with the Fourier Transformed Infrared spectroscopy (FTIR) results, they have shown that CSE contains Functional groups responsible of corrosion inhibition and other methods results.The inhibition mechanisms, estimated from the temperature dependence of inhibition efficiency as well from kinetic and activation parameters show that the extract functioned via mixed inhibition mechanism. It is suggested that molecular as well as protonated organic species in the extract contribute to the observed inhibiting action.