Isomorphous Substitution of Boron into Zeolites ZSM-5 and Y with Aqueous NH4BF4

Autor:	S. E. Schramm, D. S. Shihabi, P. T. Reischman, Clarence D. Chang, K. D. Schmitt, S. Han
Rok vydání:	1994
Předmět:	Magic angle Aqueous solution Inorganic chemistry General Engineering chemistry.chemical_element Crystallography Crystallinity Molecular geometry chemistry Isomorphous substitution Physical and Theoretical Chemistry ZSM-5 Boron Zeolite
Zdroj:	The Journal of Physical Chemistry. 98:4118-4124
ISSN:	1541-5740 0022-3654
Popis:	Treatment of ZSM-5 and Y zeolites with aqueous NH 4 BF 4 (secondary synthesis) yields [B]ZSM-5 and [B]Y. Tetrahedral B 3+ in the zeolite framework was verified by boron MAS NMR (B 3+ shift: ZSM-5=-3.6 ppm; Y=-2.7 ppm). B 3+ chemical shift was found to correlate with the Si-O-Si bond angle (from silicon MAS NMR), further demonstrating that boron has been inserted in the framework. XRD and STEM showed increasing crystallinity losses with increasing amounts of framework B 3+ , and this is believed to be due to partial and random crystal collapse to accommodate the smaller B 3+ ion
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::b8d4a64d21f5b548384115ecfb88d5aa https://doi.org/10.1021/j100066a035 Zobrazit plný text záznamu