Neolamarckia cadamba alkaloids as eco-friendly corrosion inhibitors for mild steel in 1 M HCl media
By Raja, Pandian Bothi; Qureshi, Ahmad Kaleem; Rahim, Afidah Abdul; Osman, Hasnah & Awang, Khalijah
Published in Corrosion Science
2013
Abstract
The inhibition effect of Neolamarckia cadamba crude extract (bark, leaves) and pure alkaloid (3β-isodihydrocadambine) were investigated for mild steel corrosion in 1 M HCl medium. Potentiodynamic polarization, electrochemical impedance, scanning electron microscopy, FTIR spectroscopy and molecular modelling were employed for this study. Results showed that crude extracts and 3β-isodihydrocadambine reduced the corrosion rate significantly at all concentrations. Polarization measurements indicated that these green inhibitors acted through mixed type inhibition. SEM studies evidenced the formation of a protective film over metal surface while FTIR, supported by molecular modelling proved that this shielding effect was caused by alkaloids, particularly 3β-isodihydrocadambine.