The heat of transport of carbon tetrachloride-cyclohexane liquid mixtures has been determined directly by Dufour effect experiments. The technique employs a withdrawable ''liquid gate'' to create a nonturbulent, sharp diffusional interface. The partial differential equations governing the barycentric velocity, composition, and temperature distributions are solved with a Crank-Nicholson implicit numerical scheme. This allows inclusion of the composition and temperature dependence of the thermodynamic and transport parameters. For mean mole fraction of carbon tetrachloride x1 between 0.34 and 0.55 and for mean temperature T between 295.13 and 296.43 degreesK, the best least squares fit of the data for the heat of transport 1 in kJ mol^-1 is 1=5.82+2.32 (x-1/2)+0.225 (T-295.82), with a calculated standard error of 0.087. Analysis of the same experiments indicates that the composition dependence of the thermal conductivity kappa of the mixture in the specified composition and temperature ranges is best given (in J m^-1s^-1K^-1 ) by ([partial-derivative] kappa/[partial-derivative] w1)T,p=0.0252 (w^1/2*2-0.032), where wj is mass fraction.
(c) 1980 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in The Journal of Chemical Physics and may be found at http://link.aip.org/link/?JCPSA6/72/131/1;
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