Abstract
Styrene synthesis over iron oxide model catalysts was studied by combining UHV characterization methods with in situ conversion measurements in a microflow reactor under realistic reaction conditions. Both unpromoted Fe 2O3 and K-promoted model catalysts show a similar high starting activity while that of Fe3O4 is clearly lower. Water limits and K promotion slows down deactivation by coking and oxide reduction. The deactivation can be prevented and the high initial yield preserved by adding a small amount of oxygen to the feed. Both the presence of Fe3+ and intermediate adsorption strength for ethylbenzene and styrene are essential for high conversion yields.
Original language | English (US) |
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Pages (from-to) | 56-68 |
Number of pages | 13 |
Journal | Journal of Catalysis |
Volume | 225 |
Issue number | 1 |
DOIs | |
State | Published - Jul 1 2004 |
Externally published | Yes |
Bibliographical note
Funding Information:Thanks are due to G. Ketteler and A. Schüle for thermodynamic equilibrium calculations on the system FeO 2 H 2 OH 2 and to M. Swoboda for permanent technical support. The work was supported by the Deutsche Forschungsgemeinschaft in the framework of SPP1091 (Contract No. RA 376/2-2).
Keywords
- Carbonaceous deposits
- Deactivation
- Dehydrogenation
- Ethylbenzene
- Iron oxide
- Oxygen
- Potassium
- Promoter
- Styrene
- Water
ASJC Scopus subject areas
- Catalysis
- Physical and Theoretical Chemistry