Molecular Mechanism of Propane Oxidative Dehydrogenation on Surface Oxygen Radical Sites of VOx/TiO2 Catalysts Full article
Journal |
Research on Chemical Intermediates
ISSN: 0922-6168 , E-ISSN: 1568-5675 |
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Output data | Year: 2016, Volume: 42, Number: 6, Pages: 5237-5252 Pages count : 16 DOI: 10.1007/s11164-015-2355-0 | ||||
Tags | Oxidative dehydrogenation, Oxygen radicals, Propane, Reaction path, VOx/TiO2 catalyst | ||||
Authors |
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Affiliations |
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Funding (2)
1 | Russian Foundation for Basic Research | 15-03-08070 |
2 | Russian Foundation for Basic Research | 14-03-01110 |
Abstract:
Minimum energy pathways of propane oxidative dehydrogenation to propene and propanol on supported vanadium oxide catalyst VOx/TiO2 were studied by periodic discrete Fourier transform (DFT) using a surface oxygen radical as the active site. The propene formation pathway was shown to consist of two consecutive hydrogen abstraction steps. The first step includes Cb–H bond activation of propane followed by the formation of a surface hydroxyl group V–OtH and a propyl radical n-C3H7. This step with the activation energy E* = 0.56 eV (54.1 kJ/mol) appears to be
rate-determining. The second step involves the reaction of the bridging Ob oxygen atom with the methylene C–H bond of propyl radical n-C3H7 followed by the formation of a hydroxylated surface site HOt–V4?–ObH and propene. The initial steps of the C–H bond activation during propane conversion to propanol and propene by ODH on V5+–(OtOb)
- active sites are identical. The obtained results demonstrate that participation of surface oxygen radicals as the active sites of propane ODH makes it possible to explain relatively low activation energies observed for this reaction on the most active catalysts. The presence of very active radical species in low concentration seems to be the key factor for obtaining high selectivity.
Cite:
Avdeev V.I.
, Bedilo A.F.
Molecular Mechanism of Propane Oxidative Dehydrogenation on Surface Oxygen Radical Sites of VOx/TiO2 Catalysts
Research on Chemical Intermediates. 2016. V.42. N6. P.5237-5252. DOI: 10.1007/s11164-015-2355-0 WOS Scopus РИНЦ
Molecular Mechanism of Propane Oxidative Dehydrogenation on Surface Oxygen Radical Sites of VOx/TiO2 Catalysts
Research on Chemical Intermediates. 2016. V.42. N6. P.5237-5252. DOI: 10.1007/s11164-015-2355-0 WOS Scopus РИНЦ
Dates:
Submitted: | Oct 4, 2015 |
Accepted: | Oct 30, 2015 |
Published online: | Nov 25, 2015 |
Published print: | Jun 1, 2016 |
Identifiers:
Web of science | WOS:000376450700006 |
Scopus | 2-s2.0-84948165433 |
Elibrary | 26779583 |
Chemical Abstracts | 2015:1916665 |
Chemical Abstracts (print) | 164:555830 |
OpenAlex | W2180829382 |