Volumetric Properties of the Ionic Liquid, 1-Butyl-3-methylimidazolium Tetrafluoroborate, in Organic Solvents at T =  298.15K

Abstract

Apparent molar volumes, V φ , and compressibilities, κ φ , of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][BF 4 ]) have been determined from precise density and speed-of-sound measurements in organic solvents, methanol (MeOH), acetonitrile (MeCN), tetrahydrofuran (THF), N,N-dimethylacetamide (DMA), and dimethylsulfoxide (DMSO) in the dilute region of the ionic liquid. Corresponding values at infinite dilution are estimated by the Redlich-Mayer and Pitzer equations. The results have been interpreted by the interaction of the [BMIm][BF 4 ] in the organic solvents. Results show that the structure and dielectric constant of the organic solvents play an important role for the ion-solvent interactions in these mixtures. It was found that the strength of interaction between [BMIm][BF 4 ] with the studied organic solvents has the order DMSO > DMA > MeOH > MeCN > THF.

Physicochemical Investigation of Adiponitrile-Based Electrolytes for Electrical Double Layer Capacitor

“…It is known that in several binary mixtures containing RTMS (ionic liquids) the locus of maxima/minima in V E against composition is also away from the equimolar composition. 52 53 In the case of the nitrile solvents mixtures, two major factors can explain the negative excess molar volumes observed. On one hand, the large difference in molar volume of the two components favors the packing of the molecular solvent in the natural cavities existing in the RTMS.…”

Volumetric and Isentropic Compressibility Behavior of Ionic Liquid, 1-Propyl-3-Methylimidazolium Bromide in Acetonitrile, Dimethylformamide, and Dimethylsulfoxide at T = (288.15 to 308.15) K

“…The crude product was dissolved in acetonitrile and crystallized by adding dropwise to toluene in an ice bath. The product was dried in high vacuum at 333.15 K using a rotary 1278.62 [36] 1485.12 [36] 1457.30 [42] 1280 [39] 1484.5 l [41] 1283 [40] evaporator for at least 4 h at 0.7 kPa. All the solutions were prepared by mass on a Sartorius CP124S balance precise to within ±10 −4 g. The density and speed of sound of the mixtures were measured at different temperatures with a digital vibrating-tube analyzer (Anton Paar DSA 5000, Austria) with proportional temperature control that kept the samples at the working temperature within ±10 −3 K. The apparatus was calibrated with double-distilled, deionized, and degassed water, and dry air at atmospheric pressure according to the instrument catalog.…”

Counterintuitive solvation effect of ionic-liquid/DMSO solvents on acidic C–H dissociation and insight into respective solvation

“…As the eld of ILs remains rapidly growing [1][2][3][4][5] and the combined use of ILs with conventional solvents has become more and more popular through all these years, [6][7][8] it is desirable to know some guiding principles regarding the power of solvation varied by the IL-molecular binary solvent, as compared to the situation for single or binary molecular media. However, except for some physical property studies of this category of binary media, [9][10][11][12][13][14] sparse work could be found in the literature reporting their effect on facilitating a chemical process (where bonding situation is changed) such as acidic bond-dissociation. 15 This is quite surprising, since among all kinds of chemical transformations, acidic R-H dissociation in conventional solvents, [16][17][18][19][20] recently also in ionic media, [21][22][23][24][25] oen by means of pK a study, is the most extensively investigated process, which not only laid the foundation for many most inuential physical organic principles, [26][27][28][29] but also provided some quantitative understandings of solvation effects on stabilizing various species generated upon heterolytic bond dissociation.…”