Competitive Diffusion of Gases in a Zeolite Bed: NMR and Slice Selection Procedure, Modeling, and Parameter Identification

Taking into account the previous experimental results obtained by NMR, new procedures for identifying diffusion coefficients for codiffusing benzene and hexane in intra- and intercrystallite spaces of ZSM 5 zeolite were implemented, using high-speed gradient methods and mathematical diffusion models, as well as the NMR spectra of the adsorbed mass distribution of each component in the zeolite bed. These diffusion coefficients were obtained as a function of time for different positions along the bed. Benzene and hexane concentrations in the inter- and intracrystallite spaces were calculated for every position in the bed and for different adsorption times.