No abstract

Densities of pure 1,3-dimethylimidazolium methylsulfate ionic liquid [MMIM][CH3SO4] and its mixtures with methanol have been measured with an accuracy of ±0.2 kg·m-3 over a temperature range from (313.15 to 333.15) K and a pressure range from (0.1 to 25) MPa using a vibrating tube densimeter. The isothermal compressibilities, isobaric expansivities, and excess volumes have been calculated. The uncertainties of these properties have been estimated to be ±0.05 GPa-1, ±0.2·10-4 K-1, and ±0.1 cm3·mol-1. The exceptionally strong influence of pressure and temperature on the excess volumes has been observed.

Densities of pure 1-ethyl-3-methylimidazolium ethylsulfate ionic liquid, [C 2 mim][EtSO 4 ], and its mixtures with ethanol have been measured with an accuracy of ( 0.2 kg • m -3 , over the temperature range of (283.15 to 343.15) K and pressure range of (0.1 to 35) MPa, using a vibrating tube densimeter. The experimental densities have been correlated by the Tait equation with the temperature-dependent parameters (for the pure ionic liquid) and by a van Laar type equation, involving parameters dependent on temperature and pressure (for the mixtures). Excess volumes have been derived directly from the experimental densities, and isobaric expansivities, isothermal compressibilities, and related excess properties have been calculated with the use of the correlation equation. The exceptionally strong influence of pressure and temperature on these properties has been confirmed.

Densities of pure 1-chlorobutane, pure n-hexane, and their mixtures have been measured with an accuracy of ( 0.2 kg · m -3 , over a temperature range of (283.15 to 333.15) K and a pressure range of (0.1 to 35) MPa using a vibrating tube densimeter. The experimental densities have been correlated by the Tait equation with the temperature-dependent parameters for pure components and by the van Laar-type equation with the temperature-and pressure-dependent parameters for the solution. The excess volumes have been calculated on the basis of experimental data, and the pressure and temperature influence on this property have been discussed.

Densities and excess volumes of {methyl 1,1-dimethylpropyl ether (TAME) + (benzene or cyclohexane or hexane or octane or decane or dodecane or tetradecane or hexadecane)} at 298.15 K are presented. The observed influence of the n-alkane length can be predicted qualitatively by the Flory equation of state.