Volume 11 Issue 1
A Study on Corrosion Inhibitor for Mild Steel in Ethanol Fuel Blend
Nguyen Si Hoai Vu, Pham Van Hien, Tran Van Man, Vu Thi Hanh Thu, Mai Dinh Tri and Nguyen Dang Nam
1Department of Physics & Engineering Physics, University of Science, VNU-HCM, 227 Nguyen Van Cu Street, District 5, Ho Chi Minh City 700000, Vietnam
2Faculty of Chemical Engineering, Bach Khoa University, VNU-HCM, 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City 700000, Vietnam
3Department of Physical Chemistry, University of Science, VNU-HCM, 227 Nguyen Van Cu Street, District 5, Ho Chi Minh City 700000, Vietnam
4Institute of Chemical Technology, Vietnam Academy of Science and Technology, 1 Mac Dinh Chi Street, District 1, Ho Chi Minh City 700000, Vietnam
5External Relations and Science & Technology Department, PetroVietnam University, Cach Mang Thang Tam Street, Long Toan Ward, Ba Ria City 790000, Vietnam
*Authors to whom correspondence should be addressed.
†Nguyen Si Hoai Vu and Pham Van Hien equally contributed to this work.
Abstract
The main aim of this study is to investigate Aganonerion polymorphum leaf-ethyl acetate extract (APL-EAE) and its inhibiting effect for steel in ethanol fuel blend. The immersion test, electrochemical and surface analysis techniques were successfully carried out in this research. Scanning electron microscope images indicated that the ethanol fuel blend induced pitting corrosion of steel. Remarkably, the surface of the sample containing 1000 ppm APL-EAE is smoother than the others submerged in different conditions. The electrochemical impedance spectroscopy result shows that APL-EAE has formed a good protective layer, preventing corrosive factors from hitting the steel surface. The potentiodynamic polarization data argue that the corrosion inhibition efficiency was strengthened with the increase of APL-EAE concentration. The Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy demonstrated less intensity of Fe peaks, higher intensity of C1s peak and the appearance of organic peaks (N1s, P2p, O1s) from specimens with and without APL-EAE addition. Therefore, the results suggest the formation of the protective film on steel surface and affirm that APL-EAE has served as an effective corrosion inhibitor for steel in ethanol fuel blend.
Keywords:corrosion inhibitor; ethanol fuel blend; aganonerion polymorphum; leaf extraction; electrochemistry