LOCAL-STRUCTURE DETERMINATION OF ALUMINUM IN Y-ZEOLITE - APPLICATION OF LOW-ENERGY X-RAY-ABSORPTION FINE-STRUCTURE SPECTROSCOPY

Citation
Dc. Koningsberger et Jt. Miller, LOCAL-STRUCTURE DETERMINATION OF ALUMINUM IN Y-ZEOLITE - APPLICATION OF LOW-ENERGY X-RAY-ABSORPTION FINE-STRUCTURE SPECTROSCOPY, Catalysis letters, 29(1-2), 1994, pp. 77-90
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry Physical
Journal title
ISSN journal
1011-372X
Volume
29
Issue
1-2
Year of publication
1994
Pages
77 - 90
Database
ISI
SICI code
1011-372X(1994)29:1-2<77:LDOAIY>2.0.ZU;2-X
Abstract
The local Al structure and electronic properties in Na-Y, NH4-Y and H- Y zeolites have been determined by low energy Al XAFS. The Al-O bond d istance of 1.700 angstrom in H-Y is longer than that in NH4-Y and Na-Y , 1.636 and 1.620 angstrom, respectively. In addition, the white line intensity of the Al ion in H-Y is higher than in NH4-Y and Na-Y, indic ating the electron density on the Al ion is lower in H-Y than in the o ther two catalysts. The results of experimental Al-O bond distance and white line intensities are qualitatively in agreement with theoretica lly calculated Al-O bond distances in aluminosilicate clusters. Howeve r, further work is required in order to quantitatively evaluate the ne ar edge structure of the X-ray absorption data.