Abstract
Densities of binary mixture of three ionic liquids, 1-butyl-3-methylimidazolium thiocyanate ([C(4)C(1)im][SCN]), 1-ally1-3-methylimidazolium thiocyanate ([C-1 = C-2)C(1)im][SCN]) and 3-(3-butyl-1H-imidazol-3-ium-1-yl)propanenitrile thiocyanate ([(NC)(2)C(2)C(4)im][SCN]), with methanol were measured over a temperature range of 293.15 to 323.15 K and at atmospheric pressure. Excess molar volumes (V-m(E)) were calculated from density values and correlated with Redlich-Kister polynomial equation.
Partial molar volumes at infinite dilutions (V-m,i(infinity)) of the ILs and methanol were determined from the Redlich-Kister coefficients. For all the studied systems, the V-m(E) is negative over the entire composition range. The V-m(E) and V-m,i(infinity) are interpreted in terms of intermolecular interactions in the binary mixture. Density functional theory has been used to investigate the interactions between methanol and the studied ILs. (C) 2015 Elsevier B.V. All rights reserved.