Soret Coefficient of Some Binary Liquid Mixtures

Abstract

We have measured with the thermogravitational method the Soret coef®cient of the binary liquid systems: benzenenhexane, toluenenheptane and carbon tetrachloride with heptane and hexane, in a well characterized column used in a previous work to measure the systems benzenenheptane and toluenenhexane. The obtained results show that the Soret coef®cient takes nearly the same value in the mixtures of each one of the components, benzene, toluene or carbon tetrachloride with hexane and heptane. For all the systems considered it varies slowly with the concentration and is nearly independent of temperature. The higher values of the thermal diffusion factor correspond to mixtures containing carbon tetrachloride. Previous results for these systems were obtained in an imperfect apparatus and must be disregarded.In the afore-mentioned paper [4], we also report the re-measured values of the Soret coef®cient for benzene and nheptane mixtures, which also differ from those reported by Ecenarro et al. [1]. In the present work, using the new setup, we reappraise the

Enhanced Molecular Separation in Inclined Thermogravitational Columns

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Soret Effect and Free Convection: A Way to Measure Soret Coefficients

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