Premium
A chromatographic study of diffusion of single components and binary mixtures of gases in 4A and 5A zeolites
Author(s) -
Kumar Ravi,
Duncan Robert C.,
Ruthven Douglas M.
Publication year - 1982
Publication title -
the canadian journal of chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.404
H-Index - 67
eISSN - 1939-019X
pISSN - 0008-4034
DOI - 10.1002/cjce.5450600408
Subject(s) - thermal diffusivity , chemistry , gravimetric analysis , diffusion , microporous material , zeolite , knudsen diffusion , molecular sieve , thermodynamics , adsorption , chromatography , porosity , analytical chemistry (journal) , organic chemistry , catalysis , physics
Results of a chromatographic study of diffusion of light hydrocarbons and other permanent gases in 4A and 5A zeolites are reported. The data for CF 4 and iC 4 H m , on 4A sieve (no penetration of the zeolite lattice) suggest that micropore diffusion occurs primarily by a Knudsen mechanism. The majority of the measurements were made with small particles of crushed commercial pelleted zeolites under conditions of intracrystalline diffusion control. The dominance of intracrystalline resistance is shown by the similarity in the time constants obtained with different sizes of particle and the results are generally consistent with earlier gravimetric data. The data for the binary systems containing two adsorbed species are consistent with the simple hypothesis that each species in the mixture diffuses independently with the same intrinsic mobility as for single component diffusion at the same temperature. However, the actual diffusivity of a species in the binary mixture may differ from the pure component diffusivity due to differences in the form of the quilibrium isotherms.