Sorption kinetics of n-alkane vapours on isomorphously substituted MFI-type materials

Sorption kinetics of vapours of n-butane, n-pentane, n-hexane, and n-heptane on MFI-type materials isomorphously substituted with Al, V, Sb, Ti, As, W, and Mo was investigated. Uptake curves and sorption isotherms were determined. A clear decrease in the sorbate diffusion coefficient with the length of the hydrocarbon chain of a sorbate molecule was observed. Practically, no dependence of the diffusion coefficient on the chemical composition and size of the zeolite crystals were found.