Abstract
Maleic anhydride, a precursor to polyester resins, is made by oxidation of n -butane over vanadium phosphate catalysts. This system is of general interest because it is the only heterogeneously catalyzed, alkane-selective oxidation reaction in commercial use. Time-resolved in situ x-ray absorption spectroscopy shows that when either α I -VOPO 4 /SiO 2 or (VO) 2 P 2 O 7 /SiO 2 catalysts are exposed to n -butane, the rate of maleic anhydride formation is proportional to the rate of decay of V 5+ species in the catalyst. Thus V 5+ species are kinetically significant for the production of maleic anhydride and not just for the production of by-products. The results also suggest that V 5+ species may play a role in the initial hydrogen abstraction from n -butane, the rate-determining step in the reaction sequence. V 4+ sites appear to be responsible for by-product formation.
References
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Dates
| Type | When |
|---|---|
| Created | 23 years, 1 month ago (July 27, 2002, 5:37 a.m.) |
| Deposited | 1 year, 7 months ago (Jan. 13, 2024, 1:11 a.m.) |
| Indexed | 1 month, 2 weeks ago (July 12, 2025, 6:49 p.m.) |
| Issued | 28 years, 7 months ago (Jan. 10, 1997) |
| Published | 28 years, 7 months ago (Jan. 10, 1997) |
| Published Print | 28 years, 7 months ago (Jan. 10, 1997) |
@article{Coulston_1997, title={The Kinetic Significance of V 5+ in n -Butane Oxidation Catalyzed by Vanadium Phosphates}, volume={275}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.275.5297.191}, DOI={10.1126/science.275.5297.191}, number={5297}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Coulston, George W. and Bare, Simon R. and Kung, Harold and Birkeland, Kari and Bethke, Gregory K. and Harlow, Richard and Herron, Norman and Lee, Peter L.}, year={1997}, month=jan, pages={191–193} }