Abstract:
Thermal conductivities of the four pure gases cyclopropane, propene, but-l-ene and trans-but-2- ene and their binary mixtures with argon have been measured at both 50 and 100°C. The thermal conductivities of the pure polyatomic gases lie close together and strong similarities exist in the conductivity versus composition curves for each binary mixture.
At 50°C thermal conductivities of the mixtures arc less than the molar average values and a broad minimum results in each case. At 100°C negative deviations are much reduced and only the trans- but-2-cne with argon system displays a minimum. Points of inflexion develop for the cyclopropane, propene and but-l-enc mixtures at this temperature and thermal conductivities slightly above molar average values arc seen in regions of high hydrocarbon concentration.
Thermal conductivities of the binary mixtures calculated on the basis of an empirical equation and from approximations to rigorous kinetic theory (Hirschfelder-Euckcn and Monchick, Pereira and Mason) arc compared with the experimental results. All three methods of calculation are found to give reasonably good agreement with experiment, but the Hirschfcldcr-Eucken approximation is the most satisfactory (mean deviation 0.89 % from 72 compositions) for these mixtures.
