Measurements of Multicomponent Diffusion Coefficients for the CO2–He–N2 System Using the Point Source Technique

Abstract

Measurements of the diffusion coefficient for a trace of carbon dioxide in a mixture of helium and nitrogen of varying composition have been made at room temperature and atmospheric pressure using the point source technique. The results are shown to be in agreement with the results of Fairbanks and Wilke in that an equation of the form Di−mix=[∑k lim i≠k(xk/Dik)]−1 can be used to relate the diffusion coefficient of a trace of species i in a mixture of composition given by the mole fraction xk to the binary diffusion coefficients Dik. Some data are presented on the separation of the mixture in the diffusion zone.