IN-SITU MODELING OF THE ENHANCED BRONSTED ACIDITY IN ZEOLITES

Authors
MAKAROVA MA BATES SP DWYER J
Citation
Ma. Makarova et al., IN-SITU MODELING OF THE ENHANCED BRONSTED ACIDITY IN ZEOLITES, Journal of the American Chemical Society, 117(45), 1995, pp. 11309-11313
Citations number
20
Categorie Soggetti
Chemistry
Journal title
Journal of the American Chemical Society → ACNP
ISSN journal
00027863
Volume
117
Issue
45
Year of publication
1995
Pages
11309 - 11313
Database
ISI
SICI code
0002-7863(1995)117:45<11309:IMOTEB>2.0.ZU;2-P
Abstract
Enhanced Bronsted acidity is experimentally modeled by a low-temperatu re adsorption of a Lewis acid (BF3) on the hydrogen form of EMT zeolit e. The increase in acid strength is detected in FTIR studies of a low- temperature adsorption of carbon monoxide on the samples pretreated wi th BF3. The proton affinity of Bronsted hydroxyls decreases linearly w ith increase in the surface coverage with BF3. A structure for a surfa ce complex, zeolite-Lewis acid, is proposed, and local and cooperative views on the mechanism of enhancing the acid strength of Bronsted hyd roxyls are discussed.