An amino‐based protic ionic liquid as a corrosion inhibitor of mild steel in aqueous chloride solutions

Abstract

Protic ionic liquids (PILs) have shown to be promising substances as corrosion inhibitors (CIs). In line with this, the aim of this study is to study the performance and propose the corrosion inhibition mechanism of N-methyl-2hydroxyethylamine (M-2HEAOL) and bis-2-hidroxyethylamine (B-HEAOL) oleate, for mild steel, in a neutral chloride solution. Electrochemical characterization was conducted under static and hydrodynamic conditions, and it was revealed that M-2HEAOL and B-HEAOL worked as mixed-type CIs with more interference on the anodic reaction. Inhibition efficiency depended on the concentration reaching 97% of inhibition efficiency in 5 mmol/L concentration. Scanning electron microscopy, optical interferometry, Raman spectroscopy, and Fourier-transform infrared spectroscopy are used to elicit the chemical composition of the surface film and corrosion morphology of steel in the presence of CIs, the adsorption processes of which involved physical and chemical adsorption between metal and different parts of ionic liquids. The results allowed the proposition of a corrosion inhibition mechanism.

N‐methyl‐2‐hydroxyethylammonium oleate ionic liquid performance as corrosion inhibitor for mild steel in hydrochloric acid medium

“…This mitigated formation of iron oxide-hydroxide is caused by the blocking effect of the inhibitor, which is supported by polarization curves. In addition, as reported by Schmitzhaus et al, [36] the PIL is able to form complexes with iron. It may promote the growth of the PIL adsorbed layer, as found by other authors for different inhibitors.…”

“…The role of the double bond (unsaturation) in oleic part of PIL is believed to contribute to the efficiency, because the unsaturation can be adsorbed on the metal surface by a flat adsorption process, reducing the presence of active sites and blocking the corrosion process, as Schmitzhaus et al [36] observed using the same IL in a nearly neutral solution. Porcayo-Calderon et al [94] also reported the contribution of unsaturation in the alky chains of inhibitors to the efficiency in corrosion inhibition.…”

“…In previous studies performed by our research group, Ortega Vega et al [23] reported the use of N-methyl-2-hydroxyethylammonium oleate ([m-2HEA] [Ol]) and other similar ILs as lubricants for aluminum. Furthermore, Schmitzhaus et al [36] reported in an early study that [m-2HEA][Ol] worked as mixedtype corrosion inhibitor, with predominance in anodic processes, for steel in a neutral chlorinated solution. The PILs maintained their performance even in high turbulence hydrodynamic conditions and promoted hydrophobicity on the substrate, and their adsorption was possible due to the presence of amino and carboxylic functional groups.…”

Determinação Do Perfil Inorgânico De Chás Derivados Da Camellia Sinensis

“…A Figura 1a apresenta os espectros de FTIR obtidos para a monoetanolamina, o ácido acético e o líquido iônico 2-HEAA. Os espectros característicos dos precursores da síntese são bem conhecidos e já foram descritos na literatura (BARBOSA, 2013;SCHMITZHAUS et al, 2020;CAMARGO et al, 2016 (ALVAREZ et al, 2011;BARBOSA, 2013;SCHMITZHAUS et al, 2020;CAMARGO et al, 2016…”

Ácidos Graxos Vegetais: Composição Química, Atividade Biológica E Potencial Biotecnológico

“…-H, que sobrepõem as bandas de estiramento de N-H da monoetanolamina e do cátion do LIP(ALVAREZ et al, 2011;BARBOSA, 2013;SCHMITZHAUS et al, 2020;CAMARGO et al, 2016).…”