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Solid-state NMR studies of the geometry of brønsted acid sites in zeolitic catalysts

✍ Scribed by Dieter Freude; Jacek Klinowski; Halimaton Hamdan

Publisher
Elsevier Science
Year
1988
Tongue
English
Weight
673 KB
Volume
149
Category
Article
ISSN
0009-2614

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✦ Synopsis

H 2'AI and %i solid-state NMR was used to determine the geometry of the Brsnsted acid site in zeolites. The mean distance between acidic protons in bridging hydroxyl groups and the nearest framework Al atom is 2.38 ? 0.04 8, in zeolite H-Y and 2.48 2 0.04 A in H-ZSM-5. The quadrupole frequency of framework Al is 1.02f 0.05 and 3.1 k 0.8 MHz in dehydrated Na-Y and H-Y, respectively.

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