Theoretical and electrochemical studies of cuminum cyminum (jeera) extract as green corrosion inhibitor for mild s eel in hydrochloric acid solution

Abstract

The effect of seed extract of Jeera (Cuminum Cyminum) was investigated by gravimetric, potentiodynamic polarization, electrochemical impedance spectroscopy. Polarization results revealed that the extract acted as mixed type inhibitor. It exhibited 93% IE at 300 ppm. The Rct values of electrochemical impedance spectroscopy, Rp values of Linear Polarization and icorr values of Tafel polarization were in good agreement with weight loss values. Langmuir adsorption isotherm was followed by the inhibitor. UV-Visible spectroscopy also confirmed the complex formation between the inhibitor and the mild steel surface. The low value of energy gap (ΔE) further provided support for high efficiency of the extract. © 2012 by ESG.