Cannabis Plant Extract as Inhibitor for the Corrosion of Nickel in 0.5 M H₂SO₄

摘要

The effect of extract of cannabis plant on the corrosion of nickel in aqueous 0.5M sulphuric acid wasinvestigated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarizationtechniques. EIS measurements showed that the dissolution process of nickel occurs under activationcontrol. Potentiodynamic polarization curves indicated that the plant extract behaves as mixed-typeinhibitor. The corrosion rates of nickel and the inhibition efficiencies of the extracts were calculated.The results obtained show that the extract solution of the plant could serve as an effective inhibitor forthe corrosion of nickel in sulphuric acid media. Inhibition was found to increase with increasingconcentration of the plant extract Theoretical fitting of different adsorption isotherms, Langmuir,Flory揌uggins, and the kinetichermodynamic model, were tested to clarify the nature of adsorption.Effect of temperature on the inhibitive action of cannabis extract for the corrosion of nickel in 0.5Msulphuric acid was investigated and the activation parameters of the corrosion process in absence andpresence of cannabis extract were calculated.