The excess molar properties of {x1[C6min][BF4]+x22-propanol}: Application of ERAS model

Density, rho, and viscosity, eta, of pure 1-hexyl-3-methylimidazoliumtetrafluoroborate ([C(6)mim][BF4]), 2-propanol, and binary mixture of {x(1)[C(6)mim][BF4]+x(2)2-propanol) were measured at atmospheric pressure and in the temperature range of (293.15 to 333.15) K. The excess molar volume, V-m(E), thermal expansion coefficient, alpha(p), excess thermal expansion coefficient, alpha(E)(p), and isothermal coefficient of excess molar enthalpy (partial derivative H-m(E)/partial derivative p)(T), (x), were calculated from the experimental values of density. The excess molar volumes are negative over the entire mole fraction range for this mixture and increase with increasing temperature. These data have been used to examine the applicability of Extended Real Associated Solution (ERAS) model in correlating the excess molar volume of the binary mixture. The viscosity values of the binary mixture were calculated via McAllister equation and the obtained results show a good agreement between the experimental and the calculated values in the whole composition range and all temperatures, so that the relative deviations are rarely more than 2%. The excess molar properties were correlated with the Redlich-Kister equation. (C) 2012 Elsevier B.V. All rights reserved.