2,6-Di-tert-butylpyridine sorption approach to quantify the external acidity in hierarchical zeolites

2014
journal article
article
137
cris.lastimport.wos2024-04-09T20:41:14Z
dc.abstract.enThis work was aimed to evidence that substituted pyridine, 2,6-di-tert-butylpyridine, is a suitable probe for the quantitative investigation of the external acidity in hierarchically structured zeolites. The 2,6-di-tert-butylpyridine was too large to enter the micropores, even in wide pore zeolites, and nearly no sites in nonmesoporous zeolites were available. Accessibility studies of acid sites in zeolites TNU-9 and BEA involving quantitative IR measurements with hindered 2,6-di-tert-butylpyridine as a probe were performed. The extinction coefficients of the 1615 cm-1 diagnostic bands of 2,6-di-tert-butylpyridine interacting with Brønsted acid sites were determined. Lewis acid sites were not detected with the probe. The accessibility factor (AF) for the 2,6-di-tert-butylpyridine probe molecule was defined as the number of sites detected by adsorption of the dTBPy (external sites) divided by the total amount of acid sites in the studied zeolites as quantified by pyridine sorption. Upon desilication resulting in the fabrication of the secondary mesopores, the enhanced accessibility of the protonic sites was observed. In comparison to the mesoporous zeolites with the secondary system of mesopores generated by alkaline leaching, considerably higher accessibility of protonic sites was evidenced in both ultrathin ZSM-5 and delaminated ITQ-2 zeolite.pl
dc.affiliationWydział Chemii : Pracownia Spektrometrii w Podczerwienipl
dc.affiliationWydział Chemii : Zakład Chemii Nieorganicznejpl
dc.contributor.authorGóra-Marek, Kinga - 128133 pl
dc.contributor.authorTarach, Karolina - 103685 pl
dc.contributor.authorChoi, Minkeepl
dc.date.accessioned2015-01-22T18:54:29Z
dc.date.available2015-01-22T18:54:29Z
dc.date.issued2014pl
dc.description.number23pl
dc.description.physical12266-12274pl
dc.description.volume118pl
dc.identifier.doi10.1021/jp501928kpl
dc.identifier.eissn1932-7455pl
dc.identifier.issn1932-7447pl
dc.identifier.urihttp://ruj.uj.edu.pl/xmlui/handle/item/2671
dc.languageengpl
dc.language.containerengpl
dc.rightsDodaję tylko opis bibliograficzny*
dc.rights.licencebez licencji
dc.rights.uri*
dc.subtypeArticlepl
dc.title2,6-Di-tert-butylpyridine sorption approach to quantify the external acidity in hierarchical zeolitespl
dc.title.journalThe Journal of Physical Chemistry. Cpl
dc.typeJournalArticlepl
dspace.entity.typePublication
cris.lastimport.wos
2024-04-09T20:41:14Z
dc.abstract.enpl
This work was aimed to evidence that substituted pyridine, 2,6-di-tert-butylpyridine, is a suitable probe for the quantitative investigation of the external acidity in hierarchically structured zeolites. The 2,6-di-tert-butylpyridine was too large to enter the micropores, even in wide pore zeolites, and nearly no sites in nonmesoporous zeolites were available. Accessibility studies of acid sites in zeolites TNU-9 and BEA involving quantitative IR measurements with hindered 2,6-di-tert-butylpyridine as a probe were performed. The extinction coefficients of the 1615 cm-1 diagnostic bands of 2,6-di-tert-butylpyridine interacting with Brønsted acid sites were determined. Lewis acid sites were not detected with the probe. The accessibility factor (AF) for the 2,6-di-tert-butylpyridine probe molecule was defined as the number of sites detected by adsorption of the dTBPy (external sites) divided by the total amount of acid sites in the studied zeolites as quantified by pyridine sorption. Upon desilication resulting in the fabrication of the secondary mesopores, the enhanced accessibility of the protonic sites was observed. In comparison to the mesoporous zeolites with the secondary system of mesopores generated by alkaline leaching, considerably higher accessibility of protonic sites was evidenced in both ultrathin ZSM-5 and delaminated ITQ-2 zeolite.
dc.affiliationpl
Wydział Chemii : Pracownia Spektrometrii w Podczerwieni
dc.affiliationpl
Wydział Chemii : Zakład Chemii Nieorganicznej
dc.contributor.authorpl
Góra-Marek, Kinga - 128133
dc.contributor.authorpl
Tarach, Karolina - 103685
dc.contributor.authorpl
Choi, Minkee
dc.date.accessioned
2015-01-22T18:54:29Z
dc.date.available
2015-01-22T18:54:29Z
dc.date.issuedpl
2014
dc.description.numberpl
23
dc.description.physicalpl
12266-12274
dc.description.volumepl
118
dc.identifier.doipl
10.1021/jp501928k
dc.identifier.eissnpl
1932-7455
dc.identifier.issnpl
1932-7447
dc.identifier.uri
http://ruj.uj.edu.pl/xmlui/handle/item/2671
dc.languagepl
eng
dc.language.containerpl
eng
dc.rights*
Dodaję tylko opis bibliograficzny
dc.rights.licence
bez licencji
dc.rights.uri*
dc.subtypepl
Article
dc.titlepl
2,6-Di-tert-butylpyridine sorption approach to quantify the external acidity in hierarchical zeolites
dc.title.journalpl
The Journal of Physical Chemistry. C
dc.typepl
JournalArticle
dspace.entity.type
Publication
Affiliations

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