Mobility of n-Butane in ZSM-5 Zeolite Studied by 2H NMR Full article
| Journal |
The Journal of Physical Chemistry C
ISSN: 1932-7447 , E-ISSN: 1932-7455 |
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| Output data | Year: 2010, Volume: 114, Number: 7, Pages: 2958-2966 Pages count : 9 DOI: 10.1021/jp908464f | ||||
| Tags | SOLID-STATE NMR; NUCLEAR-MAGNETIC-RESONANCE; MFI-TYPE ZEOLITES; MOLECULAR-DYNAMICS; ROTATIONAL MOTION; SIDE-CHAINS; ALKANES; RELAXATION; SILICALITE; DIFFUSION | ||||
| Authors |
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| Affiliations |
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Funding (2)
| 1 | Russian Foundation for Basic Research | 09-03-93113 |
| 2 | Russian Foundation for Basic Research | 05-03-34762 |
Abstract:
The mobility of linear alkane, n-butane, adsorbed in zeolite ZSM-5 was investigated by deuterium solid-state NMR (2H NMR). Analysis of the 2H NMR spectra line shape and spin−lattice relaxation time permitted characterizing the influence of pore confinement on the dynamics of the molecule over a broad temperature range (123−413 K). It has been found, that at a loading of two molecules per unit cell, n-butane molecules are essentially located in both straight and zigzag channels and not the intersections. The adsorbed molecules are involved in fast intramolecular motions and reorientation as a whole. Intramolecular motions are methyl group rotation and conformational exchange occurring at τ ≈ 4−8 × 10−11 s (at 300 K) with an activation barrier of Eci ≈ 11−12 kJ mol−1. The reorientation of the molecule as whole is a complex anisotropic motion, which consists of jump exchange between neighboring channels, occurring at τD ≈ 3.7 × 10−10 s (at 300 K) with an activation barrier of ED ≈ 5 kJ mol−1 and of other rotational modes that may correspond to uniaxial rotation and librations of n-butane in the pores. Influence of pore confinement on the dynamics of the adsorbed alkane is manifested by the complete suppression of isotropic reorientation.
Cite:
Kolokolov D.I.
, Jobic H.
, Stepanov A.G.
Mobility of n-Butane in ZSM-5 Zeolite Studied by 2H NMR
The Journal of Physical Chemistry C. 2010. V.114. N7. P.2958-2966. DOI: 10.1021/jp908464f WOS Scopus РИНЦ ANCAN OpenAlex
Mobility of n-Butane in ZSM-5 Zeolite Studied by 2H NMR
The Journal of Physical Chemistry C. 2010. V.114. N7. P.2958-2966. DOI: 10.1021/jp908464f WOS Scopus РИНЦ ANCAN OpenAlex
Dates:
| Submitted: | Sep 2, 2009 |
| Accepted: | Jan 19, 2010 |
| Published online: | Feb 2, 2010 |
| Published print: | Feb 25, 2010 |
Identifiers:
| Web of science: | WOS:000274578700019 |
| Scopus: | 2-s2.0-77649142018 |
| Elibrary: | 15313264 |
| Chemical Abstracts: | 2010:134350 |
| Chemical Abstracts (print): | 152:320585 |
| OpenAlex: | W2013718563 |