Isothermal activity coefficients for the system cyclohexane—n-heptane—toluene at 25°C



Isothermal vapor-liquid equilibrium data at 25°C are presented for the ternary and binary system containing cyclohexane, n-heptane, and toluene. These data were obtained by static equilibration in the presence of diluent nitrogen by chromatographic analysis of the saturated vapor. The data obtained were of at least comparable accuracy to those available at the normal boiling point, and the procedure appears to offer several substantial advantages. Neither a priori prediction of activity coefficients from regular solution theory nor extrapolation of data taken at the normal boiling point is a satisfactory substitute for the isothermal data.