Exploring low-temperature dehydrogenation at ionic Cu sites in beta zeolite to enable alkane recycle in dimethyl ether homologation [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 666.9 Masonry adhesives
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Science ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
• Mô tả vật lý: Size: p. 3662-3667 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 263250
• Chủ đề: 1. 09 biomass fuels; 2. 37 inorganic, organic, physical, and analytical chemistry; 3. C-h activation; 4. Copper; 5. Dehydrogenation

Tóm tắt

 Cu-based catalysts containing targeted functionalities including metallic Cu, oxidized Cu, ionic Cu, and Bronsted acid sites were synthesized and evaluated for isobutane dehydrogenation. Hydrogen productivities, combined with <
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  X-ray absorption spectroscopy, indicated that Cu(I) sites in Cu/BEA catalysts activate C-H bonds in isobutane. Computational analysis revealed that isobutane dehydrogenation at a Cu(I) site proceeds through a two-step mechanism with a maximum energy barrier of 159 kJ/mol. Furthermore, these results demonstrate that light alkanes can be reactivated on Cu/BEA, which may enable re-entry of these species into the chain-growth cycle of dimethyl ether homologation, thereby increasing gasoline-range (C<
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 5+<
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 ) hydrocarbon yield.