Selective two-component self-diffusion measurement of adsorbed molecules by pulsed field gradient Fourier transform NMR

Molecular Simulations of Zeolites: Adsorption, Diffusion, and Shape Selectivity

“…Such a slight influence on the less mobile component was also observed experimentally for methane/ethane in MFI 404 and FAU. 405 These different examples illustrate that for multicomponents it is difficult to even qualitatively predict the effect of the other components. PFG NMR experiments for diffusion of nC 4 -iC 4 mixtures in both FAU and MFI are found to be in good agreement with MD simulations.…”

Adsorption and Diffusion Behavior of Ethane and Ethylene in Sol-Gel Derived Microporous Silica

“…It is thus reasonable to assume that ethane will also exhibit an enhanced mobility in silica relative to ZSM-5. Hong et al (1991) have examined the diffusivities of ethane and ethylene in NaX zeolites at 293 K. When adsorbed separately, the diffusivity of ethane is an order of magnitude larger than that of ethylene. When coadsorbed, however, the diffusivity of ethylene is nearly unchanged whereas that of ethane is reduced by roughly a factor of two.…”

“…Jobic et al (1997) have also examined the unidirectional and single file diffusion of C 1 -C 3 normal and cyclic alkanes. Hong and co-workers (Hong et al 1991) have compared the diffusivities of ethane and ethylene in NaX zeolites, both for the individual species and when the two species were co-adsorbed. When both species were present, the diffusivity of ethylene was virtually unchanged whereas the diffusivity of ethane was reduced.…”

Diffusion Measurements by NMR Techniques

“…The ability of PFG NMR, to monitor simultaneously the mobility of different components [159,164] makes it a very effective tool for studying the mobility of the reactant and product molecules during chemical reaction. Figure 19 shows the results of in-situ PFG NMR measurement during the conversion of cyclopropane to propene in zeolite Na-X [165].…”