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1H solid-state NMR studies of the geometry of Brønsted acid sites in zeolites H-ZSM-5

✍ Scribed by Michael Hunger; Dieter Freude; Dieter Fenzke; Harry Pfeifer

Publisher
Elsevier Science
Year
1992
Tongue
English
Weight
419 KB
Volume
191
Category
Article
ISSN
0009-2614

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✦ Synopsis

Broad-line 'H NMR and 'H MAS NMR were used to determine the geometry of the Bransted acidic sites in zeolites H-ZSM-5. The signals obtained correspond to bridging hydroxyl groups in Si-OH-Al arrangements with an H-Al distance of 0.246-0.252 nm. The concentration of hypothetical SiOHSi groups must be less than 0.26 species per unit ceil.

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