Soret Coefficient of Some Binary Liquid Mixtures

Abstract

We have measured with the thermogravitational method the Soret coefficient of the binary liquid systems: benzene+nhexane, toluene+nheptane and carbon tetrachloride with heptane and hexane, in a well characterized column used in a previous work to measure the systems benzene+nheptane and toluene+nhexane. The obtained results show that the Soret coefficient 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.