UV-Raman spectroscopy, X-ray photoelectron spectroscopy, and temperature programmed desorption studies of model and bulk heterogeneous catalysts [electronic resource].
- Washington, D.C. : United States. Dept. of Energy, 2002. and Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Physical Description:
- vp : digital, PDF file
- Additional Creators:
- Lawrence Berkeley National Laboratory, United States. Department of Energy, and United States. Department of Energy. Office of Scientific and Technical Information
- X-ray photoelectron spectroscopy (XPS) and Temperature Programmed Desorption (TPD) have been used to investigate the surface structure of model heterogeneous catalysts in ultra-high vacuum (UHV). UV-Raman spectroscopy has been used to probe the structure of bulk model catalysts in ambient and reaction conditions. The structural information obtained through UV-Raman spectroscopy has been correlated with both the UHV surface analysis and reaction results. The present day propylene and ethylene polymerization catalysts (Ziegler-Natta catalysts) are prepared by deposition of TiCl₄ and a Al(Et)₃ co-catalyst on a microporous Mg-ethoxide support that is prepared from MgCl₂ and ethanol. A model thin film catalyst is prepared by depositing metallic Mg on a Au foil in a UHV chamber in a background of TiCl₄ in the gas phase. XPS results indicate that the Mg is completely oxidized to MgCl₂ by TiCl₄ resulting in a thin film of MgCl₂/TiClₓ, where x = 2, 3, and 4. To prepare an active catalyst, the thin film of MgCl₂/TiClₓ on Au foil is enclosed in a high pressure cell contained within the UHV chamber and exposed to ≈1 Torr of Al(Et)₃.
- Dissertation Note:
- Thesis (Ph.D.); Submitted to University of California, Berkeley, CA (US); PBD: 19 Aug 2002
- Published through SciTech Connect., 08/19/2002., "lbnl--51336", "B& R KC0203010", and Tewell, Craig R.
- Funding Information:
- AC03-76SF00098 and 517101
View MARC record | catkey: 14393639