Speeds of sound, isentropic compressibilities, viscosities and excess molar volumes of binary mixtures of methylcyclohexane + 2-alkanols or ethanol at T = 298.15 K

https://doi.org/10.1016/j.jct.2005.04.019Get rights and content

Abstract

Speeds of sound u, isentropic compressibilities κS, viscosities η, excess isentropic compressibilities κSE, excess molar volumes VmE, excess viscosities ηE, and excess Gibbs energy of activation ΔG 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, VmE is positive and both ηE and ΔG E are negative. The κSE 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.

Introduction

This paper is a continuation of our earlier work related to the study of thermodynamic properties of binary mixtures [1], [2], [3], [4]. In recent years, measurements of thermodynamic, acoustic and transport properties have been adequately employed in understanding the nature of molecular systems and physico-chemical behavior in liquid mixtures. The nonrectilinear behavior of above mentioned properties of liquid mixtures with changing mole fractions is attributed to the difference in size of the molecules and strength of interactions. Here, we have reported densities, viscosities, speeds of sound, isentropic compressibilities, excess isentropic compressibilities, excess viscosities and excess molar volumes of MCH binary mixtures with six linear 2-alkanols (C3 to C8) and ethanol at T = 298.15 K. This work will also provide a test of various empirical equations to correlate viscosity and speeds of sound of binary mixtures containing one polar and one nonpolar component.

Section snippets

Experimental

Methylcyclohexane (mass fraction > 0.99), ethanol (mass fraction > 0.99), 2-propanol (mass fraction 0.99), 2-butanol (mass fraction 0.99), 2-pentanol (mass fraction > 98), 2-hexanol (mass fraction > 0.98), 2-heptanol (mass fraction > 0.99) and 2-octanol (mass fraction > 0.97) were purchased from Merck. 2-Octanol was purified by the standard method described by Perrin and Armarego [5]. Densities of the pure liquids and their mixtures at T = 298.15 K were measured with an Anton Paar digital densimeter (Model

Densities and excess molar volumes

The excess molar volumes of the solutions of molar composition x were calculated from the densities of the pure liquids and their mixtures according to the following equation:VmE/(m3·mol-1)=[xM1+(1-x)M2]/ρ-[xM1/ρ1+(1-x)M2/ρ2],where ρ, ρ1 and ρ2 are the densities of the solution and pure components 1 and 2, respectively, and M1 and M2 are the molar masses of the pure components. The excess molar volumes are accurate to ±3 · 10−4 m3 · mol−1. The corresponding VmE values of binary mixtures of [x1MCH + (1

Acknowledgements

Authors are thankful to the authorities of the University for the providing the necessary facilities to carry out the work.

References (40)

  • H.A. Zarei et al.

    Thermochim. Acta

    (2003)
  • J. Weclawski et al.

    Fluid Phase Equilib.

    (1983)
  • A. Rodriguez et al.

    Fluid Phase Equilib.

    (2004)
  • G. Savaroglu et al.

    Fluid Phase Equilib.

    (2004)
  • R. Tanaka et al.

    Thermochim. Acta

    (1988)
  • V. Brandani

    Fluid Phase Equilib.

    (1983)
  • R. Alonso et al.

    J. Chem. Thermodyn.

    (1990)
  • R. Alonso et al.

    J. Chem. Thermodyn.

    (1989)
  • G.C. Benson et al.

    J. Chem. Thermodyn.

    (1979)
  • K. Tamura et al.

    J. Chem. Thermodyn.

    (1984)
  • H. Iloukhani, M.R. Sameti, J. Chem. Thermodyn. 37 (2005) in...
  • H. Iloukhani et al.

    J. Solution Chem.

    (2003)
  • H. Iloukhani et al.

    J. Solution Chem.

    (2001)
  • D.D. Perrin et al.

    Purification of Laboratory Chemicals

    (1970)
  • C. Kretschmer et al.

    J. Am. Chem. Soc.

    (1949)
  • T. Shinomiya

    Bull. Chem. Soc. Jpn.

    (1989)
  • Handbook of Chemistry and Physics, CRC Press, 2000, pp. 180–184 (Section...
  • Handbook of Chemistry and Physics, CRC Press, 2000, pp. 31–53 (Section...
  • D. Kulikov et al.

    J. Chem. Eng. Data

    (2001)
  • E.S. Domalski et al.

    J. Phys. Chem. Ref. Data

    (1993)
  • Cited by (0)

    View full text