COLL 468 |
| T. A. Nijhuis1, Tom Visser1, and Bert M. Weckhuysen2. (1) Inorganic Chemistry, Utrecht University, Sorbonnelaan 16, Utrecht, 3584CA, Netherlands, (2) Department Inorganic Chemistry and Catalysis, Universiteit Utrecht, Debye Instituut, Sorbonnelaan 16, 3508 TC Utrecht, Netherlands |
| Gold on titania catalysts have attracted considerable attention for their potential to directly epoxidize propene using a hydrogen/oxygen mixture. The common assumption is that gold helps produce peroxide-like reaction intermediates which can epoxidize propene over the titania support, but experimental evidence is lacking. Different gold on titania catalysts have been prepared and were investigated using simultaneous UV-VIS / Raman operando spectroscopic techniques. The aim of the spectroscopic study is to try do determine what kind of reaction intermediates are present on the catalyst surface. Especially Raman is highly sensitive towards the suspected peroxide intermediates. The gold catalysts that were synthesized proved to be highly selective (>95 %) at conversion levels up to 1.2 %. Operando Raman showed the reversible formation of intense bands due to propoxy adsorbates in the 1200-1600 cm-1 Raman shift region. The aim is to develop a kinetic model by combining activity data and spectroscopic observations. |
|
Symposium in Memory of Arthur W. Adamson
8:30 AM-11:50 AM, Thursday, April 1, 2004 Marriott -- Orange County 3, Oral
Division of Colloid and Surface Chemistry |