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Acidity of MCM-58 and MCM-68 zeolites in comparison with some other 12-ring zeolites
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SYSNO ASEP 0341551 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Acidity of MCM-58 and MCM-68 zeolites in comparison with some other 12-ring zeolites Tvůrce(i) Gil, B. (PL)
Košová, Gabriela (UFCH-W)
Čejka, Jiří (UFCH-W) RID, ORCID, SAIZdroj.dok. Microporous and Mesoporous Materials. - : Elsevier - ISSN 1387-1811
Roč. 129, 1-2 (2010), s. 256-266Poč.str. 11 s. Jazyk dok. eng - angličtina Země vyd. NL - Nizozemsko Klíč. slova MCM-58 ; MCM-68 ; Bronsted and Lewis acid centres Vědní obor RIV CF - Fyzikální chemie a teoretická chemie CEP GA104/07/0383 GA ČR - Grantová agentura ČR FT-TA3/080 GA MPO - Ministerstvo průmyslu a obchodu CEZ AV0Z40400503 - UFCH-W (2005-2011) UT WOS 000273862900033 DOI 10.1016/j.micromeso.2009.10.003 Anotace Two novel zeolites MCM-58 and MCM-68 with 12-ring channels and containing the cages in the structure were investigated with respect to their acidic properties and compared with other two 12-ring zeolites, namely Beta and ZSM-12. The main objective was to characterize the accessibility and acid strength of Lewis and Bronsted sites using FTIR spectroscopy. Pyridine adsorption allowed for quantification of Bronsted and Lewis acid centres and pointed out that while in the structure of MCM-58 nearly all Al atoms form acidic Si-OH-Al bridges, only about half of Al is a source of the Bronsted acidity in MCM-68. The special attention was devoted to the origin and location of the hydrogen-bonded OH groups in the MCM-58 zeolite. The frequency lowering is caused by the across-the-ring interaction with the oxygen atom and not by the interaction with the nearby OH groups, as proved by high temperature activation and deuteration experiments. Pracoviště Ústav fyzikální chemie J.Heyrovského Kontakt Michaela Knapová, michaela.knapova@jh-inst.cas.cz, Tel.: 266 053 196 Rok sběru 2011
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