This paper reports on the synthesis and the physical properties of the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate (EMISE). Experimental densities, speeds of sound and refractive indices were determined from (288.15 to 343.15) K. Dynamic viscosities were measured from (298.15 to 343.15) K and surface tension were measured from (288.15 to 313.15) K for pure ionic liquid. Densities, dynamic viscosities, speeds of sound, and isentropic compressibilities have been determined over the whole composition range for ethanol (1) + EMISE (2) and water (1) + EMISE (2) binary systems at T ) (298.15, 313.15, and 328.15) K and atmospheric pressure. Excess molar volumes, viscosity deviations, and deviations in isentropic compressibility for the binary systems were fitted to a Redlich-Kister equation to determine the fitting parameters and the root mean square deviations. Refractive indices were measured at 298.15 K over the whole composition range for the ethanol (1) + EMISE (2) and water (1) + EMISE (2) binary systems. The results were used to calculate deviations in the refractive index.

Density, speed of sound, refractive index, and viscosity of the commercial ionic liquids 1-ethyl-3-methylpyridinium bis(trifluoromethylsulfonyl, and 1-hexyl-3-methylimidazolium dicyanamide, [HMim][N(CN) 2 ] were measured as a function of temperature at atmospheric pressure. The density, speed of sound, and refractive index data were properly fitted to a linear equation, while viscosity data were fitted to Arrheniuslike law, Vogel−Fulcher−Tamman (VFT), a modified VFT, Litovitz, and fluidity equations. Besides, from the experimental density values, the thermal expansion coefficient, α, was calculated. Moreover, the experimental data were used to analyze the effect of temperature, the role of the alky chain length of the cation, and the influence of the nature of the ions (cation and anion) on the physical properties. Finally, an exhaustive comparison with available literature data of the studied ionic liquids was also carried out.

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In this contribution, dynamic viscosities, densities, and speeds of sound of 1-ethyl-3-methylimidazolium ethyl sulfate (EMISE) with methanol, 1-propanol, and 2-propanol at T ) (298.15, 313.15, and 328.15) K and refractive indices at T ) 298.15 K and at atmospheric pressure have been measured over the whole composition range. Excess molar volumes, excess molar isentropic compressions, and viscosity deviations for the binary systems from T ) 298.15 K to T ) 328.15 K and refractive deviations at 298.15 K have been calculated and were satisfactorily fitted to a Redlich-Kister equation to give the fitting parameters and the root-mean-square deviations.

In this work, experimental data of isobaric vapor-liquid equilibria for the ternary system ethanol + water + 1-butyl-3-methylimidazolium chloride ([C 4 mim][Cl]) and for the corresponding binary systems containing the ionic liquid (ethanol + [C 4 mim][Cl] and water + [C 4 mim][Cl]) were measured at 101.3 kPa. Vapor-liquid equilibria experimental data of binary and ternary systems were correlated by the NRTL equation. NRTL parameters have been used to predict the evolution of the ethanol-water azeotrope composition with different amounts of ionic liquid.

In this work, experimental data of isobaric vapor-liquid equilibria (VLE) for the ternary system ethanol + water + 1-ethyl-3-methylimidazolium ethylsulfate (EMISE) and for the corresponding binary systems containing the ionic liquid (ethanol + EMISE, water + EMISE) were carried out at 101.3 kPa. VLE data of binary systems were correlated using the e-NRTL and NRTL equations. With the obtained parameters, we can predict the behavior of the ternary system. In addition, the ternary system was correlated using the NRTL equation. A study of the evolution of the ethanol + water azeotrope composition with different amounts of ionic liquid was made.

Ionic liquids are good candidates as replacements for current heat-transfer liquids used in industry. For this use, it is important to know their thermal behavior. The melting, freezing, cold crystallization, and glass transition temperatures, together with heat capacities in the temperature range (293.15 to 333.15) K of the ionic liquids 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [C n MimNTf 2 (n = 2,3,4,6)], 1-hexyl-3-methylimidazolium trifluoromethanesulfonate (C 6 MimTFO), and 1-hexyl-3-methylimidazolium dicyanamide (C 6 MimDCA), have been determined using differential scanning calorimetry. Three different types of thermal behaviors were found, and in general it was concluded that as the temperature scan rate in the thermal analysis increases, the freezing temperature decreases, and the glass transition and cold crystallization temperatures increase. The heat capacity values of the imidazolium ionic liquids with the bis(trifluoromethylsulfonyl)imide anion increase as the alkyl-side chain of the cation increases, and the ionic liquid with this anion has higher heat capacities than their homologues with trifluoromethanesulfonate or dicyanamide as anions.

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