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• In this paper, we report the corrosion inhibition of amino acid imidazole ionic liquids ([CyVIm][AA]ILs) on mild steel in neutral media, which has not been studied before. • In addition, the corrosion inhibition performance of [CyVIm][AA]ILs in neutral media was evaluated comprehensively by a combination of experiments and simulations as well as an in-depth investigation of the corrosion inhibition mechanism. The corrosion inhibition properties of three amino acid imidazole ionic liquids ([CyVIm][AA]) as corrosion inhibitors for mild steel in a 3.5 wt% NaCl corrosion medium were evaluated by electrochemical measurements. The polarization experiments show that [CyVIm][AA] influences anode reaction processes, demonstrating that [CyVIm][AA] is an anodic inhibitor type corrosion inhibitor. [CyVIm]Try outperforms [CyVIm]His and [CyVIm]Pro in terms of corrosion inhibition. The results of surface analysis and quantum chemical calculations show that [CyVIm]Try can form a protective film on the surface of mild steel and inhibit surface corrosion. Furthermore, by applying molecular dynamics simulations, after investigating the corrosion inhibitor adsorption trends on the Fe (1 1 0) surface, the interaction order between the molecular framework of the Fe corrosion inhibitor and the Fe (1 1 0) surface for entanglement was determined. According to the radial distribution function, the corrosion inhibitor adsorption mode on the metal surface is composite adsorption with chemisorption as the major mode and physical adsorption as the secondary mode. [ABSTRACT FROM AUTHOR]

This work presents a comparative study of the electrochemical behaviour, on a glassy carbon electrode, of dissolved EuCl 3 in two chlorobasic ionic liquids, the 1-ethyl-3-methylimidazolium chloride, C 2 mimCl, and the 1-buthyl-3-methylimidazolium chloride, C 4 mimCl, over the temperature ranges 363–398 K and 343–363 K respectively. In both media, the electro-reduction of EuCl 6 3 − takes place via only one electrochemical step EuCl 6 3 − /EuCl 6 4 − . The electrochemical system EuCl 6 4 − /Eu(0) has not been observed within the electrochemical window of both ILs, due to the prior reduction of the respective imidazolium cation from the solvents, which inhibits the electro-extraction of Eu(0) from the media on the GC electrode. The paper describes how several electrochemical techniques (e.g. cyclic voltammetry (CV), convolutive potential sweep voltammetry (CPSV), steady state voltammetry (SSV), chronopotentiometry (CP) and chronoamperometry (CA)) have been used experimentally: i) verifying assumptions used in their theoretical analysis, and ii) ensuring reproducible conditions at the electrode/electrolyte interface, with the aim to obtain high-precision measurements of the diffusion coefficient of EuCl 6 3 − . In order to know if there are discrepancies between the obtained data, a two-way analysis of variance, ANOVA, has been carried out. The analysis has shown that with a 95% confidence level there are no significant differences between the diffusion coefficients obtained by the different techniques. On the other hand, the diffusion coefficient of EuCl 6 3 − increases with the temperature following the Arrhenius law, being the activation energy for diffusion 40.4 ± 2.6 and 60.2 ± 1.8 kJ mol − 1 in C 2 mimCl and C 4 mimCl respectively. The dimensionless Schmidt numbers, defined as the ratio between solvent viscosity and solute diffusivity ( Sc = ν/D), have also been calculated to characterise the solute global mass transport through its environment. On the GC electrode, the electro-reduction of EuCl 6 3 − to EuCl 6 4 − is a quasi-reversible process. Accurate values of the kinetic parameters (i.e. the intrinsic rate constant of charge transfer, k 0 , and the charge transfer coefficient, α), as well as the reversible half wave potential, E r 1/2 , have been obtained for the first time in the mentioned ionic liquids, by simulation of the cyclic voltammograms and logarithmic analysis of the voltammograms and convoluted curves. [ABSTRACT FROM AUTHOR]

In this paper we describe the electro-oxidation of methyl-substituted aromatic compounds to the corresponding aldehydes in aqueous imidazole ionic liquid (IL) solutions and using a platinum electrode. The electro-oxidative behavior of p -methoxy toluene ( p -MT) was studied in the ILs using cyclic voltammetry (CV), and the oxidation was shown to be an irreversible process. Increasing the acid strength of the ILs led to further oxidation to the corresponding acid. The controlled potential electrolysis of methyl-substituted aromatic compounds was also investigated under the optimized reaction conditions and the products were detected by NMR, IR and gas chromatography/mass spectrometry (GC/MS). The method represents a promising way to prepare aromatic aldehydes. In order to detect intermediates, in-situ Fourier transform infrared spectroscopy (in-situ FTIR) data was acquired during the oxidation processes. The results further confirmed that the procedure provides a selective approach to the synthesis of aromatic aldehydes. The selectivity toward formation of the corresponding aromatic aldehydes was 21–92% when using the optimized reaction conditions. Excellent electrochemical stability of the ILs was demonstrated and they could be recycled at least 35 times. [ABSTRACT FROM AUTHOR]