Density and Viscosity of Binary Mixtures of 1-Ethyl-3-methylimidazolium Heptachlorodialuminate and Tetrachloroaluminate Ionic Liquids

Abstract

The densities and viscosities of binary mixtures of 1-ethyl-3-methylimidazolium heptachlorodialuminate and tetrachloroaluminate ionic liquids with different molar compositions were measured by high-precision vibrating tube densimeter and automated microviscometer from 293.15 to 353.15 K. On this basis, the excess molar volumes and excess viscosities of binary mixtures were also calculated for the first time. All the experimental data were well fitted by the empirical equations. According to the results of computational calculations, enhanced molecular symmetry and molar concentration of heptachlorodialuminate anion usually lead to higher density. The hydrogen bonding among ions is confirmed as one of the most important structural parameters in determining the viscosity of ionic liquids. It shows that Lewis acidic 1-ethyl-3-methylimidazolium chloroaluminate can be treated as the classic binary mixtures of heptachlorodialuminate and tetrachloroaluminate ionic liquids. Looser packing and/or weaker interionic interaction probably occurs after the formation of binary mixtures. The results and conclusions of this work will help to promote future research and application of chloroaluminate ionic liquids.

Temperature Dependence on Density, Viscosity, and Electrical Conductivity of Ionic Liquid 1-Ethyl-3-Methylimidazolium Fluoride

“…Numerous studies have focused on designing new ILs and on the relationship between the phase behavior and molecular structure, in order to clarify the nature of ILs and expand their applications [11][12][13][14][15].…”

Fundamental Insights into Electrical and Transport Properties of Chloroaluminate Ionic Liquids for Aluminum-Ion Batteries

“…Since γ is a thermodynamic factor that accounts for the deviation from an ideal solution, stronger ion interactions in chloroaluminate ILs are expected to result in a larger deviation in γ value. Three major ion interactions in ILs are Coulombic, hydrogen bonding, and van der Waals interactions. − In this work, we utilize cation–anion interaction energy (Δ E int ) determined by DFT calculations to probe the contribution of Coulombic and hydrogen bonding interaction in chloroaluminate ILs. − The calculated Δ E int for [X + ]­[AlCl 4 – ] and [X + ]­[Al 2 Cl 7 – ] ion pairs are presented in Table , and the details are provided in Table S3. Judging from the magnitude of Δ E int , we predict the overall Coulombic and hydrogen bonding interactions to increase in the order of AlCl 3 -TMAHCl > -TEAHCl > -EMIMCl ≈ -BMIMCl IL.…”

“…In addition to Coulombic interactions, another contributing factor on Δ E int is the hydrogen bonding between the protons in X + and electronegative Cl atoms in AlCl 4 – and Al 2 Cl 7 – . − As presented in Figure a and Table , there are a total of eight hydrogen bonds between TMAH + and chloroaluminate anions, with the shortest H···Cl bond distance (2.24 Å) in the [TMAH + ]­[AlCl 4 – ] ion pair. Given that the H···Cl distance is indicative of the strength of the hydrogen bond, a shorter H···Cl bond distance implies higher hydrogen bond energy.…”

Electrodeposition of Nanocrystalline Aluminium from 1-Ethyl-3-methylimidazolium Chloroaluminate with Niacinamide as an Efficient Additive

“…Each optimized molecular structure was checked with minimum energy at the corresponding level. Basis set superposition errors have been considered in the calculations of interaction energy by the counterpoise method [19].…”

“…The water content of the ionic liquid has been calculated by Karl Fisher titration (751 GPD Titrino, Metrohm, Switzerland). The results of these data are listed as follows [19]. 1 .…”