Volume 2012 (2012), Article ID 574321, 9 pages
Inhibitory Mechanism of Carbon Steel Corrosion in Sea Water by an Aqueous Extract of Henna Leaves
1PG and Research Department of Chemistry, GTN Arts College, Tamil Nadu, Dindigul 624005, India
2Department of Chemistry, RVS School of Engineering and Technology, Dindigul 624005, India
3Department of Chemistry, Shanmuganathan Engineering College, Arasampatti 622507, India
Received 19 September 2012; Accepted 27 October 2012
Academic Editors: A. A. Franco and E. Stupnisek-Lisac
Copyright © 2012 V. Johnsirani et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The inhibition efficiency (IE) of an aqueous extract of henna leaves in controlling corrosion of carbon steel in seawater has been evaluated by weight-loss method. The weight loss study reveals that the formulation consisting of 8 mL of henna extract (HE) and 25 ppm of Zn2+ has 94% inhibition efficiency in controlling corrosion of carbon steel in sea water. Polarization study reveals that HE and Zn2+ system functions as mixed type inhibitor. AC impedance spectra reveal that protective film is formed on the metal surface. The nature of the metal surface has been analysed by FTIR spectra, SEM, and AFM analysis.