Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

In this work, the experimental densities and dynamic viscosities of binary mixtures of ammonium-based room temperature asymmetrical Gemini ionic liquids (GILs), 1-trimethylammonium-3-(pyridinium) propane bisdicyanamide ([N111C3Py][DCA]2) and 1-trimethylammonium-3-(1-methylpiperidinium) propane bisdicyanamide ([N111C3MPi][DCA]2), with methanol (MeOH) or ethanol (EtOH) over the entire concentration range have been respectively determined experimentally at temperatures of (293.15, 303.15 , 313.15, 323.15, and 323.15) K in the atmospheric pressure. The excess molar volumes (VmE), excess dynamic viscosities () and excess Gibbs energy of activation (G*E) of the mixtures have been evaluated according to the experimental and values of pure [N111C3Py][DCA]2, [N111C3MPi][DCA]2, MeOH, EtOH, and their binary solutions at the investigated temperatures and pressure. The change of VmE and were correlated with the Redlich-Kister-type expression and optimal fitting parameters were evaluated. It was observed that values of VmE and are negative deviations from ideal behaviors for the four binary systems. With the mole fraction of alcohol decreasing, these excess properties for these mixtures exists more negative deviations from ideal solutions, until a minimum excess values are reached. Negative values of VmE and for the four binary solutions indicate stronger interactions between GIL and alcohol molecules compared to the pure components and better packing owing to the differences in size and shape of the investigated molecules. Positive values of G*E can be ascribed to the size effect of mixing components. Meanwhile, the dependence of these excess properties on temperature for all binary systems indicates that the temperature has a great influence on intermolecular interactions in the studied mixtures.