ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Ethanol extracts of Hemidesmus indicus leaves as eco-friendly inhibitor of mild steel corrosion in H₂SO₄ medium

Niketan S. Patel and Dalimil Šnita

Department of Chemical Engineering, Institute of Chemical Technology, Technická 5, 16628, Prague 6, Czech Republic

E-mail: niketan.ptl@gmail.com

Abstract: The inhibitory action of an extract of Hemidesmus indicus leaves as a potential corrosion inhibitor for steel in H₂SO₄ solutions was examined using conventional mass loss, gasometric techniques, electrochemical polarisations and electrochemical impedance spectroscopy. The results revealed that the extract of Hemidesmus indicus leaves performed well as an inhibitor for the corrosion of the metal employed in an accelerating medium. The inhibition efficiencies for all the experimental techniques employed increased with increasing the concentration of the plant extract but decreased with a rise in temperature. Both the cathodic hydrogen evolution and the anodic dissolution of mild steel were inhibited, hence the active molecule of the extract studied acted as a mixed-type corrosion inhibitor.

Keywords: Hemidesmus indicus – corrosion inhibition – electrochemical polarisation – electrochemical impedance spectroscopy – mild steel

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-014-0625-8

Chemical Papers 68 (12) 1747–1754 (2014)