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On the location of iron and aluminium atoms in thermally activated AlMCM-58 and FeMCM-58 zeolites

SYSNO ASEP	0375929
Document Type	J - Journal Article
R&D Document Type	Journal Article
Subsidiary J	Článek ve WOS
Title	On the location of iron and aluminium atoms in thermally activated AlMCM-58 and FeMCM-58 zeolites
Author(s)	Gil, B. (PL) Marszalek, B. (PL) Adamski, A. (PL) Olejniczak, Z. (PL) Kubů, Martin (UFCH-W)_RID Čejka, Jiří (UFCH-W)_{RID, ORCID, SAI}
Source Title	Microporous and Mesoporous Materials. - : Elsevier - ISSN 1387-1811 Roč. 151, MAR 2012 (2012), s. 339-345
Number of pages	7 s.
Language	eng - English
Country	NL - Netherlands
Keywords	MCM-58 ; heteroatom location ; IR, EPR and NMR spectroscopy
Subject RIV	CF - Physical ; Theoretical Chemistry
R&D Projects	GAP106/11/0819 GA ČR - Czech Science Foundation (CSF)
	GD203/08/H032 GA ČR - Czech Science Foundation (CSF)
CEZ	AV0Z40400503 - UFCH-W (2005-2011)
UT WOS	000300747000044
DOI	10.1016/j.micromeso.2011.10.014
Annotation	FTIR study of iron and aluminium forms of zeolite MCM-58 showed that location of heteroatoms in this IFR structure depends on the type of heteroatom. The combination of the pyridine and CO adsorption allowed determination of the concentration of hydroxyls in the 12- and 5/6-rings. Both Fe and Al are generating hydroxyls pointing towards either 12-ring or 5/6-rings but the former are located in positions giving Si–OH–Fe hydroxyls pointing mainly to the 12-rings while the latter gives rise to the Si–OH–Al groups pointing primarily to the narrower 5- and 6-rings. (Al)MCM-58 undergoes only minor dehydroxylation associated with the acid sites even at temperatures as high as 700 °C, which indicates unique stabilization of Al atoms in the IFR structure. In the case of (Fe)MCM-58, dehydroxylation is more extensive. Furthermore the OH located in the 5/6-rings dehydroxylate at lower temperatures than those in the 12-rings. The study also demonstrates that the concentration of the framework and extraframework iron atoms can be determined by a simple method based on pyridine adsorption followed by IR spectroscopy.
Workplace	J. Heyrovsky Institute of Physical Chemistry
Contact	Michaela Knapová, michaela.knapova@jh-inst.cas.cz, Tel.: 266 053 196
Year of Publishing	2013

Number of the records: 1