Catalytic and structural effects of W-substitution in M2 Mo-V-Te-oxide for propene ammoxidation
Författare
Summary, in English
Substitution of W for the Mo in M2-type Mo-V-Te-oxide was investigated. XRD, FTIR, XANES, and HRTEM verified that the substitution is possible in the whole range up to complete replacement of Mo by W. Catalytic measurements for propene ammoxidation show that both the specific activity and the selectivity to acrylonitrile pass through a maximum with increase of the W-content of the catalyst. XRD analysis indicates that the catalytic results, in part, can be explained by a disordered distribution of Mo, W, and V among the octahedral sites in M2 giving better catalytic performance than a more ordered arrangement does. Moreover, SEM and HRTEM imaging show that with increasing W-content, the M2 crystals change from μm-sized elongated crystals to spherical crystals of nm-size, influencing the type of surfaces being exposed and consequently the catalytic properties. Among the catalysts investigated, a catalyst with the composition (Mo0.3W0.7)1.9V1.0Te1.1O10 is the most active and selective one, giving 80% selectivity to acrylonitrile.
Publiceringsår
2007
Språk
Engelska
Sidor
153-160
Publikation/Tidskrift/Serie
Catalysis Today
Volym
128
Issue
3-4
Dokumenttyp
Artikel i tidskrift
Förlag
Elsevier
Ämne
- Chemical Sciences
- Chemical Engineering
Nyckelord
- Ammoxidation
- Mo-V-W-Te-oxide catalysts
- M2-phase
- W-substitution
- XRD
- SEM
- XANES
- Acrylonitrile
- Propene
- HRTEM
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 0920-5861