Frequency-response study of micro- and macro-pore diffusion in manufactured zeolite pellets

Abstract

Intra- and inter-crystalline diffusion of carbon dioxide and isobutane in different manufactured 5A and 13X pellets have been investigated by the frequency-response method. Despite three orders of magnitude difference in micropore diffusivities for carbon dioxide in 5A and 13X zeolite crystals, its macropore diffusivities in 5A and 13X pellets are nearly the same. The macropore diffusivities were found to be the controlling step in all pellets under study. The diffusivity of carbon dioxide was found to be about twice that of isobutane in the macropores of 13X pellets.