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Ammoxidation of Propane over Antimony-Vanadium-Oxide Catalysts

Nilsson, Roland; Lindblad, Thomas and Andersson, Arne LU (1994) In Journal of Catalysis 148(2). p.501-513
Abstract
Catalysts belonging to the Sb-V-O system were prepared with various Sb/V ratios and were used for propane ammoxidation to acrylonitrile. XRD patterns of freshly prepared samples show those with excess vanadia to consist of V2O5 and SbVO4, while SbVO4 and α-Sb2O4 are constituents in the samples with a Sb/V ratio above unity. High rate and selectivity for propylene formation at low conversion are characteristic for samples with excess vanadia and considering XRD, Raman, infrared, and XPS results, this is explained by formation of amorphous vanadia spread over the surface of SbVO4. Catalysts with both α-Sb2O4 and SbVO4 phases are the most selective for acrylonitrile formation, a function that is linked to their ability to selectively... (More)
Catalysts belonging to the Sb-V-O system were prepared with various Sb/V ratios and were used for propane ammoxidation to acrylonitrile. XRD patterns of freshly prepared samples show those with excess vanadia to consist of V2O5 and SbVO4, while SbVO4 and α-Sb2O4 are constituents in the samples with a Sb/V ratio above unity. High rate and selectivity for propylene formation at low conversion are characteristic for samples with excess vanadia and considering XRD, Raman, infrared, and XPS results, this is explained by formation of amorphous vanadia spread over the surface of SbVO4. Catalysts with both α-Sb2O4 and SbVO4 phases are the most selective for acrylonitrile formation, a function that is linked to their ability to selectively transform intermediate propylene. XPS data suggest this function to be associated with the formation of suprasurface antimony sites on SbVO4 as a result of migration of antimony from α-Sb2O4 during the catalytic process. Raman and infrared spectral features revealed that compared with SbVO4, the samples with both α-Sb2O4 and SbVO4 are more efficiently reoxidised during propane ammoxidation. Rate dependences on the partial pressures of reactants over a sample with excess α-Sb2O4 show that the adsorption of propane is the rate limiting step for propylene formation, and that acrylonitrile and carbon oxides are predominantly formed from the intermediate propylene in routes comprising nonequilibrated steps. Addition of water vapour results in an increase of rate and selectivity for acrylonitrile formation. The kinetic dependences indicate that for acrylonitrile formation it is advantageous to have a feed rich in propane and to use recirculation for obtaining high productivity. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Catalysis
volume
148
issue
2
pages
501 - 513
publisher
Elsevier
external identifiers
  • wos:A1994NZ02600009
  • scopus:0000043376
ISSN
1090-2694
DOI
10.1006/jcat.1994.1236
language
English
LU publication?
yes
id
4b509d63-2a45-4b70-ba0e-4e900a8df217 (old id 35833)
date added to LUP
2007-06-15 15:52:04
date last changed
2017-03-26 03:30:01
@article{4b509d63-2a45-4b70-ba0e-4e900a8df217,
  abstract     = {Catalysts belonging to the Sb-V-O system were prepared with various Sb/V ratios and were used for propane ammoxidation to acrylonitrile. XRD patterns of freshly prepared samples show those with excess vanadia to consist of V2O5 and SbVO4, while SbVO4 and α-Sb2O4 are constituents in the samples with a Sb/V ratio above unity. High rate and selectivity for propylene formation at low conversion are characteristic for samples with excess vanadia and considering XRD, Raman, infrared, and XPS results, this is explained by formation of amorphous vanadia spread over the surface of SbVO4. Catalysts with both α-Sb2O4 and SbVO4 phases are the most selective for acrylonitrile formation, a function that is linked to their ability to selectively transform intermediate propylene. XPS data suggest this function to be associated with the formation of suprasurface antimony sites on SbVO4 as a result of migration of antimony from α-Sb2O4 during the catalytic process. Raman and infrared spectral features revealed that compared with SbVO4, the samples with both α-Sb2O4 and SbVO4 are more efficiently reoxidised during propane ammoxidation. Rate dependences on the partial pressures of reactants over a sample with excess α-Sb2O4 show that the adsorption of propane is the rate limiting step for propylene formation, and that acrylonitrile and carbon oxides are predominantly formed from the intermediate propylene in routes comprising nonequilibrated steps. Addition of water vapour results in an increase of rate and selectivity for acrylonitrile formation. The kinetic dependences indicate that for acrylonitrile formation it is advantageous to have a feed rich in propane and to use recirculation for obtaining high productivity.},
  author       = {Nilsson, Roland and Lindblad, Thomas and Andersson, Arne},
  issn         = {1090-2694},
  language     = {eng},
  number       = {2},
  pages        = {501--513},
  publisher    = {Elsevier},
  series       = {Journal of Catalysis},
  title        = {Ammoxidation of Propane over Antimony-Vanadium-Oxide Catalysts},
  url          = {http://dx.doi.org/10.1006/jcat.1994.1236},
  volume       = {148},
  year         = {1994},
}