DFT Study on Interaction of Estrone and Imidazolium-Based Hydrophobic Ionic Liquids

Affinity of estrone on imidazolium-based hydrophobic ionic liquids was computed at the B3LYP/6-31G(d) level. Columbian interactions and other closed-shell interactions, in general, were observed to be pivotal to the binding of the EDC species on visualizing the optimized structures as well as probing the proximity of electronegative and electropositive groups between estrone and ionic liquids. The interaction strength was also studied using calculation of binding energy values of each system. [BMIM]+[PF6]− was found to be the most binding ionic liquid. Estrone was found to be highly bonded in the vicinity of [PF6]− species with a binding energy of −9.57 kcal/mol. The Ionic Liquids under study, [BMIM]+[NTF2]− and [BMIM]+[BF4]−, also illustrated promising binding nature with binding energies of −7.63 and −8.61 kcal/mol. AIM analysis was carried out to validate the nature of intermolecular interactions by calculating the topological properties at (3,−1) bond critical points

Evaluation of Solution Thermodynamic Properties of Mixed Ionic Liquids at Different Temperatures (293.15–343.15) K

The solution thermodynamic properties of mixed ionic liquids such as density, excess molar volume, partial molar volume and apparent molar volume are highly influential on the design of an effective separation unit and in the optimization of operating parameters like pressure, temperature and concentration for the separation processes. Therefore, it could be better to do a prior experimental study on of the solution thermodynamic properties of mixed ionic liquids at different temperatures for the whole mole fractions rather than doing separation characterization studies like selectivity, efficiency, distribution coefficient and performance index. In addition, the recovery and regeneration of ionic liquids also challenge researchers and separation scientists in several fields of applications. Therefore, in this chapter, density of pure 1-butyl-3-methyl imidazolium bis(trifluoromethylsulfonyl) imide {[BIMIM][NtF2]}, 1-ethyl-3-methylimidazolium ethyl sulfate {[EMIM][ESO4]}, 1-ethyl-3-methylimidazolium hydrogen sulfate {[EMIM][HSO4]} and 1-butyl-3-methylimidazolium acetate {[BMIM][OAc]} and its binary mixtures have been measured at T (293.15–343.15) K. From the measured densities, isobaric expansivity, excess molar volume, partial molar volume, excess partial molar volume, and apparent molar volume have been calculated. Results were discussed in terms of physical interaction, chemical interaction and structural orientation at molecular level and their temperature and composition dependency

Physiochemical Properties of Hydrodenitrification and Hydrodesulphurization Inhibiting Compounds with 1-Ethyl-3-Methylimidazolium Ethylsulphate at T = (298.15 to 323.15) K and =1 Bar

This work investigates the ability of 1-ethyl-3-methylimidazolium ethylsulphate ([emim][EtSO4]) as a green and tuneable solvent for denitrification and desulphurization of diesel oil. Experimental density, surface tension, and refractive index data have been measured for the following systems: [emim][EtSO4](1) + pyridine(2), [emim][EtSO4](1)+ pyrrole(2), [emim][EtSO4](1) + quinoline(2), [emim][EtSO4](1) + indoline(2), [emim][EtSO4](1) + thiophene(2), and [emim][EtSO4](1) + water(2) over the entire mole fraction of [emim][EtSO4] at temperatures of (298.15 to 323.15) K and at atmospheric pressure. Further, from experimental density values, coefficient of thermal expansivity and excess molar volume were also calculated. It was found that the heteroaromatic nitrogen/sulphur compounds and water are completely miscible in the [emim][EtSO4] ionic liquid. The surface tension values were found to increase while the refractive index decrease with increasing mole fraction of [emim][EtSO4]. On the other hand, dissimilar molecule such as water showed mobility of ions on mixing resulting in lower surface tension. The experimental values of surface tension increased in the order: thiophene > pyridine > pyrrole > indoline > quinoline and for refractive index: quinoline > indoline > pyrrole > pyridine > thiophene > water. It was found that the composition of [emim][EtSO4] has a greater influence than temperature in deciding the densities, surface, optical, and thermodynamic properties

Phase Behaviour of 1-Ethyl-3-methylimidazolium Thiocyanate Ionic Liquid with Catalytic Deactivated Compounds and Water at Several Temperatures: Experiments and Theoretical Predictions

Density, surface tension and refractive index were determined for the binary mixture of catalytic deactivated compounds with 1-ethyl-3-methylimidazolium thiocyanate {[EMIM][SCN]} at temperature of (298.15 to 323.15) K. For all the compounds with ILs, the densities varied linearly in the entire mole fraction with increasing temperature. From the obtained data, the excess molar volume and deviation of surface tension and refractive index have been calculated. A strong interaction was found between similar (cation-thiophene or cation-pyrrole) compounds. The interaction of IL with dissimilar compounds such as indoline and quinoline and other multiple ring compounds was found to strongly depend on the composition of IL at any temperatures. For the mixtures, the surface tension decreases in the order of: thiophene > quinoline > pyridine > indoline > pyrrole > water. In general from the excess volume studies, the IL-sulphur/nitrogen mixture has stronger interaction as compared to IL-IL, thiophene-thiophene or pyrrole-pyrrole interaction. The deviation of surface tension was found to be inversely proportional to deviation of refractive index. The quantum chemical based COSMO-RS was used to predict the non-ideal liquid phase activity coefficient for all mixtures. It indicated an inverse relation between activity coefficient and excess molar volumes