کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10244781 | 47702 | 2005 | 13 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Selective oxidation of benzene to phenol with nitrous oxide over MFI zeolites
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
کاتالیزور
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چکیده انگلیسی
Three MFI zeolites with iron ([Fe]MFI), aluminum ([Al]MFI), or a combination thereof ([Fe,Al]MFI) as framework substituents were hydrothermally synthesized. The evolution of the iron and aluminum species during template removal and further hydrothermal activation was carefully studied by UV-vis, ESR, 27Al NMR, infrared spectroscopy, and high-resolution TEM. Directly after synthesis, Fe and Al appear to be incorporated to a large extent into the zeolite framework. Iron is clearly less stable at framework positions than aluminum. The migration of iron to extraframework positions readily proceeds during template removal. Although a large fraction of framework iron is removed upon calcination in [Fe]MFI and [Fe,Al]MFI, the extent of Fe3+ clustering is more pronounced in the latter material. A more severe steam activation step is required to extract a substantial amount of aluminum from framework positions. In contrast to [Al]MFI and [Fe]MFI, [Fe,Al]MFI shows good performance in selective oxidation of benzene to phenol. A comparison of IR spectra of adsorbed NO2 groups points to the presence of various extraframework species. After the activation of [Fe,Al]MFI an extraframework mixed metal oxide species is formed, which is argued to be essential for selective oxidation of benzene to phenol with nitrous oxide.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Catalysis - Volume 233, Issue 1, 1 July 2005, Pages 123-135
Journal: Journal of Catalysis - Volume 233, Issue 1, 1 July 2005, Pages 123-135
نویسندگان
E.J.M. Hensen, Q. Zhu, R.A.J. Janssen, P.C.M.M. Magusin, P.J. Kooyman, R.A. van Santen,