Surface Diffusion of Deuterium and Light Hydrocarbons in Microporous Vycor Glass

Abstract

The significance of the surface diffusion of helium through a microporous Vycor glass is emphasized, and the experimental evidence is presented. New permeability data of D₂, CH₄, C₂H₆, and C₃H₈ are reported over a wide temperature range, and the results are analyzed numerically. Interesting comparisons are made for D₂-H₂ and C₃H₈-CO₂ systems. Finally, the separation factors for CO₂-C₃H₈ and CH₄-C₃H₈ systems are discussed. All the experimental work has been carried out with porous Vycor glass as the microporous medium. However, there is good reason to believe that the basic findings will hold for any other microporous barrier. Differences will only be a matter of magnitude and will be determined by the adsorption interaction of the respective gas-solid system.