We have designed and constructed a thermogravitational column for determining the Soret coefficient of liquid mixtures. The excellent agreement of the results obtained for toluene and n-hexane mixtures with recent accurate measurements performed by optical methods shows the validity of the thermogravitational method when a column with the correct geometry is used. We have applied this technique to determine the Soret coefficient of the binary systems benzene-n-heptane and carbon tetrachloride with cyclohexane, methanol and ethanol. Comparison with the literature data allows us to determine the reliability of the existing measurements of thermal diffusion for these mixtures.
Experimental data on ordinary diffusion coefficients and thermal diffusion factors for binary liquid systems containing hexane, heptane, benzene, toluene and carbon tetrachloride are derived from steady-state and non-steady-state separation measurements in a thermal diffusion column. The data extraction method uses a time evolution theory previously developed by the authors that accounts for the forgotten effect. Comparison of the diffusion data with those of the literature provides a test of the derived thermal diffusion factors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.