Experimental and theoretical studies of two imidazolium-based ionic liquids as inhibitors for mild steel in sulfuric acid solution. (June 2015)

• Record Type: Journal Article
• Authors: Zheng, Xingwen; Zhang, Shengtao; Li, Wenpo; Gong, Min; Yin, Linliang
• Is Part Of: Corrosion science. Volume 95(2015)
• Page Start: 168
• Page End: 179
• Publication Date: 2015-06
• Subjects: A. Mild steel -- B. EIS -- B. Polarization -- B. Weight loss -- B. SEM -- C. Acid inhibition; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2015.03.012
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: OMIMBr and [AOIM]Br are modest cathodic inhibitors for mild steel in 0.5 M H2 SO4 . AOIMBr shows better corrosion inhibition due to the allyl electron-donating group. Inhibitor mainly physically adsorbs on steel surface via positively charged N atom. The adsorption of inhibitor molecules obeys El-Awady thermodynamic–kinetic model. Abstract: The inhibition performance and mechanism of 1-octyl-3-methylimidazolium bromide ([OMIM]Br) and 1-allyl-3-octylimidazolium bromide ([AOIM]Br) for the corrosion of mild steel in 0.5 M H2 SO4 were investigated using weight loss method, electrochemical measurements, scanning electron microscope (SEM) and quantum chemical calculation. The results revealed that [OMIM]Br and [AOIM]Br acted as modest cathodic inhibitors, and due to the electron-donating effect of allyl group, [AOIM]Br showed better inhibitive performance. The adsorption of both inhibitors on steel surface obeyed El-Awady thermodynamic–kinetic model, thus the thermodynamic and kinetic parameters were calculated and discussed. Moreover, theoretical calculation was used to investigate inhibition mechanism of studied inhibitors.