Journal of Chemical Thermodynamics, Vol.38, No.2, 190-200, 2006
Speeds of sound, isentropic compressibilities, viscosities and excess molar volumes of binary mixtures of methylcyclohexane+2-alkanols or ethanol at T=298.15 K
Speeds of sound u, isentropic compressibilities kappa(S), viscosities eta, excess isentropic compressibilities kappa(E)(S), excess molar volumes V-m(E), excess viscosities eta(E), and excess Gibbs energy of activation Epsilon G(*E) of viscous flow have been investigated for seven binary mixtures of methylcyclohexane (MCH) with ethanol, 2-propanol, 2-butanol, 2-pentanol, 2-hexanol, 2-heptanol, and 2-octanol at 298.15 K. Excess properties were calculated therefrom and were correlated by Redlich-Kister type function in terms of mole fractions. For mixtures of MCH with used 2-alkanols, over the entire range of mole fractions, V-m(E) is positive and both eta(E) and Delta G(*E) are negative. The kappa(E)(S) values are large and positive over the entire range of composition for mixtures of MCH with ethanol, 2-propanol, 2-butanol and for mixtures of MCH with 2-pentanol, 2-hexanol, 2-heptanol and 2-octanol change sign from positive in the 2-alkanol rich regions to negative in MCH rich regions. These results are consistent with the self-association of 2-alkanols and the nonpolar character of MCH, which produces the dissociation of the 2-alkanols. The viscosity, speeds of sound and isentropic compressibility data have been correlated with the various equations. (C) 2005 Elsevier Ltd. All rights reserved.
Keywords:methylcyclohexane;2-alkanol;ethanol;speed of sound;viscosity;excess molar volume;self-association