Inhibitive effect of Leaves Extract of Coccinia Indica on the Corrosion of Mild Steel in Hydrochloric Acid
J. Environ. Nanotechnol., Volume 2, No 4 (2013) pp. 21-27
Abstract
The inhibitive effect of the acid extract of Coccinia indica (CI) leaves on the corrosion of mild steel (MS) in hydrochloric acid medium was studied using weight loss and electrochemical methods. The inhibition efficiency increased with increase in concentration of the extract but decreased with rise in temperature. Furthermore, the inhibition efficiency synergistically increased on the addition of halide ions. Polarization measurement studies revealed that CI extract behaves as a mixed inhibitor. Physical adsorption mechanism is proposed from the trend in inhibition efficiency with the change in temperature and from thermodynamic parameters. It has been found that the adsorption of CI on MS complies with Langmuir and Temkin adsorption isotherms. FTIR confirmed the adsorption of CI on MS surface.
Full Text
Reference
Abdel-Rehim, S. S., Ibrahim, M. A. M., Khaled, K. F., The inhibition of 4-(2'-amino-5'-methylphenylazo) antipyrine on corrosion of mild steel in HCl solution Mater. Chem. Phys., 70, 268-273(2001).
http://dx.doi.org/ 10.1016/S0254-0584(00)00462-4.
Abiola, O. K., Otaigbe, J. O. E., Kio, O. J., Gossipium hirsutum L. extracts as green corrosion inhibitor for aluminum in NaOH solution Corros. Sci., 51, 1879-1881(2009) .
http://h t t p : / / d x . d o i . o r g / 1 0 . 1 0 1 6 / j.corsci.2009.04.016.
Bockris, J. O. M., Drazic, D., Despic, R., The electrode kinetics of the deposition and dissolution of iron, Electrochim. Acta., 4, 325-361(1961).
http://dx.doi.org/10.1016/0013-4686(61)80026-1.
Da Rocha, J. C., Da Cunha Ponciano Gomes, J. A., D’Elia, E., Corrosion inhibition of carbon steel in hydrochloric acid solution by fruit peel aqueous extracts, Corros. Sci., 52, 2341-2348(2010).
http://http://dx.doi.org/10.1016/ j.corsci.2010.03.033.
El-Etre, A. Y., Inhibition of C-steel corrosion in acidic solution using the aqueous extract of zallouh root. Mater. Chem. Phys., 108, 278-282(2008).
http://dx.doi.org/10.1016/ j.matchemphys.2007.09.037.
Gopi, D., Govindaraju, K. M., Kavitha, L., Investigation of triazole derived Schiff bases as corrosion inhibitors for mild steel in hydrochloric acid medium, J.Appl. Electrochem., 40, 1349-1356(2010).
http://http:// dx.doi.org/ 10.1007/s10800-010-0092-z.
Jeyaprabha, C., Sathiyanarayanan, S., Muralidharan, S., Venkatachari, G., Corrosion inhibition of iron in 0.5 mol L-1 H2SO4 by halide ions J.Braz. Chem. Soc., 17, 61– 67(2006).
http://dx.doi.org/10.1590/ S0103-50532006000100009.
Li, X. H., Mu, G. N., Tween-40 as corrosion inhibitor for cold rolled steel in sulphuric acid: Weight loss study, electrochemical characterization, and AFM, Appl. Surf. Sci., 252, 1254-1265(2005).
http://http://dx.doi.org/ 10.1016/j.apsusc.2005.02.118.
Li, X. M. , Tang, L. B., Li, L., Mu, G. N., Liu, G. H., Synergistic inhibition effect of 6-benzylaminopurine and iodide ion on the corrosion of cold rolled steel in H3PO4 solution, Corros.Sci., 48, 308-321(2006).
