Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Preferential occupation of xenon in zeolite MCM-22 as revealed by Xe-129 NMR spectroscopy
Autore:
Chen, F; Deng, F; Cheng, MJ; Yue, Y; Ye, CH; Bao, XH;
Indirizzi:
Chinese Acad Sci, Wuhan Inst Phys & Math, State Key Lab Nucl Magnet Resonance & Atom & Mol, Wuhan 430071, Peoples R China Chinese Acad Sci Wuhan Peoples R China 430071 an 430071, Peoples R China Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis, Dalian 116023, Peoples R China Chinese Acad Sci Dalian Peoples R China 116023 n 116023, Peoples R China
Titolo Testata:
JOURNAL OF PHYSICAL CHEMISTRY B
fascicolo: 39, volume: 105, anno: 2001,
pagine: 9426 - 9432
SICI:
1520-6106(20011004)105:39<9426:POOXIZ>2.0.ZU;2-Q
Fonte:
ISI
Lingua:
ENG
Soggetto:
NUCLEAR-MAGNETIC-RESONANCE; MICROPOROUS SOLIDS; MOLECULAR-DYNAMICS; CHEMICAL-SHIFTS; NAY ZEOLITE; ADSORPTION; DEPENDENCE; DIFFUSION; BENZENE; ZSM-12;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
41
Recensione:
Indirizzi per estratti:
Indirizzo: Deng, F Chinese Acad Sci, Wuhan Inst Phys & Math, State Key Lab Nucl Magnet Resonance & Atom & Mol, Wuhan 430071, Peoples R China Chinese Acad Sci Wuhan Peoples R China 430071 1, Peoples R China
Citazione:
F. Chen et al., "Preferential occupation of xenon in zeolite MCM-22 as revealed by Xe-129 NMR spectroscopy", J PHYS CH B, 105(39), 2001, pp. 9426-9432

Abstract

Adsorption of xenon in zeolite MCM-22, a zeolite containing two separate pore systems (the 10-membered ring (MR) sinusoidal channels and 12-MR supercages interconnected by 10-MR window system), has been investigated in detail with Xe-129 NMR spectroscopy as a function of Xe loadings over a wide range of temperatures (120-350 K). NMR results suggest that Xe atoms are preferentially adsorbed in the supercages of the zeolite at low Xe pressure (less than a few atmospheres), while Xe atoms can penetrate into the two-dimensional sinusoidal channels at high Xe pressure. No direct exchange between the Xe in the supercages and the sinusoidal channels was observed in variable-temperature (VT) Xe-129 NMR experiments for all of the samples, which is in line with the crystal structure of the zeolite. However, when the Xe adsorption pressure is greater than 6 atm, two different kinds of Xe exchange were observed in VT experiments over the temperature range. The exchange ofXe at the different adsorption sites in the same supercage (i.e., Xe atomsin the two pockets and those in the central part of the supercage) occurs at lower temperatures (170-122 K), which is demonstrated by two-dimensionalXe-129 NMR exchange spectroscopy. The exchange between Xe in the supercageand the sinusoidal channel takes place through gaseous Xe in the interparticle space at higher temperatures (280-350 K).

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 31/03/20 alle ore 18:46:50