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[摘要]：Glass-ceramics offer high melting points (1200-1500 degrees C), excellent attrition-resistance, and very low coefficients of thermal expansion. We have found that these materials can be employed to create active supported catalysts, bulk catalysts, or a combination of the two. Supported catalysts are created by the process of thermal impregnation in which thermal energy is employed to graft oxides of catalytically active metals directly into the surfaces of glass-ceramic and mineral-based supports. Bulk catalysts are prepared by heat-treating specially formulated Li and Mg-aluminosilicate glasses containing up. to 40 wt % NiO to create a fine-grained (0.5-5 mu m) multiphase, crystalline ceramic. When any of these materials are reduced with hydrogen, exposed surfaces reveal a metallic state. Laboratory testing with simulated syngas mixtures containing surrogate tars (naphthalene and toluene) shows that these new materials can exhibit strong catalytic activity for tar and methane decomposition as well as methanation at lower temperatures. This work is supported by US-DOE Cooperative Agreement DE-FG36-04GO14314 and GTI internal research funding, (C) 2009 American Institute of Chemical Engineers Environ Prog, 28: 336-346, 2009 |
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