Effect of Catharanthus roseus ( Vince rosea) and Turmeric ( Curcuma longa) Extracts as Green Corrosion Inhibitors for Mild Steel in 1 M HCl

Abstract

The corrosion inhibition of mild steel by Catharanthus roseus (Vince rosea) and Turmeric (Curcuma longa) extracts as green inhibitors in 1 M HCl solutions has been investigated by using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), hydrogen evolution measurements and scanning electron microscope (SEM) techniques. Results obtained show that these investigated compounds are good inhibitors and act as mixed type inhibitors. The inhibition efficiencies increase with increasing inhibitor concentration. The SEM results show the formation of protective film on the mild steel surface in the presence of Catharanthus roseus and Turmeric extracts. The results obtained from different tested techniques are in good agreement.