Why silver is the unique catalyst for ethylene epoxidation

Date

2011-12-01

Author

Ozbek, M. O.
Önal, Işık
van Santen, R. A.

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The activities of Cu(2)O(001), Ag(2)O(001), and Au(2)O(001) surfaces for direct ethylene epoxidation and alternative paths for EO isomerization are studied. Among these three oxide surfaces, only Ag(2)O(001) surface enables direct path without a barrier. Au(2)O cannot regenerate surface oxygen, and overall reaction on Cu(2)O is endothermic. Furthermore, ring opening of ethylene oxide (EO) and subsequent acetaldehyde (AA) formation on Cu(2)O is more favorable than EO desorption. Ethylene adsorption on an oxygen vacancy results in the oxametallacycle (OMC) formation, which causes AA formation and reduces EO selectivity. Cl adsorption removes these surface vacant sites and hence prevents the formation of the OMC intermediate.

Subject Keywords

Oxide surface, Ethylene oxide, Cu(2)O, Ag(2)O, Au(2)O, Ethylene, DFT

URI

https://hdl.handle.net/11511/32056

Journal

JOURNAL OF CATALYSIS

DOI

https://doi.org/10.1016/j.jcat.2011.08.004

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

M. O. Ozbek, I. Önal, and R. A. van Santen, “Why silver is the unique catalyst for ethylene epoxidation,” JOURNAL OF CATALYSIS, pp. 230–235, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32056.