PFG NMR self-diffusion measurements in microporous adsorbents.

A survey is given on the possibilities of pulsed field gradient (PFG) NMR to study molecular diffusion in beds of microporous adsorbent particles (zeolite crystallites). Depending on the given adsorbate-adsorbent system, the PFG NMR data on intracrystalline diffusion are both in agreement and disagreement with the results of uptake measurements. Two novel routes to unveil the origin of such discrepancies are described.

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