The diffusion thermoeffect (Dufour effect) in gaseous mixtures of hydrogen and carbon dioxide

Abstract

Measurements of the diffusion thermo-effect as a function of pressure and the initial composition of diffusing mixtures are reported for hydrogen and carbon dioxide at room temperature. Temperature-time curves have been obtained with the thermometer at six positions above and below the diffusion interface. A solution the two coupled differential equations derived from the phenomenologioal description of the effect (excluding all cross terms containing temperature gradients) shown to agree well with the experimental curves. The agreement is best when the thermometer is not too close to the diffusion interface and the initial concentrations the diffusing mixtures are nearly equal.