NMR INVISIBLE ALUMINUM SPECIES IN DEALUMINATED MORDENITE ZEOLITE - A H-1 AL-27 TRAPDOR NMR-STUDY/

Authors
Citation
F. Deng et al., NMR INVISIBLE ALUMINUM SPECIES IN DEALUMINATED MORDENITE ZEOLITE - A H-1 AL-27 TRAPDOR NMR-STUDY/, Science in China. Series B, Chemistry, life sciences & earth sciences, 41(2), 1998, pp. 149-155
Citations number
10
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry
ISSN journal
1001-652X
Volume
41
Issue
2
Year of publication
1998
Pages
149 - 155
Database
ISI
SICI code
1001-652X(1998)41:2<149:NIASID>2.0.ZU;2-6
Abstract
Various kinds of aluminum species in dealuminated mordenite were inves tigated in detail, and the quadrupole coupling constants (QCCs) for al uminum atoms associated with these species were obtained by means of t he newly introduced H-1/Al-27 TRAPDOR method as well as Al-27 magic an gle spinning (MAS) nuclear magnetic resonance (NMR). QCC values of 11. 3, 15.3, 13.3 and (14.0 +/- 0.6) MHz were determined from the TRAPDOR profiles for Lewis acid sites, Bronsted acid sites (SiOHAl) and two ki nds of non-framework aluminum species Al(OH)(n), respectively. The sou rce of the ''invisible Al'' is discussed on the basis of the NMR exper imental results.