Catalytic combustion of methane over Pt and PdO-supported CeO2–ZrO2–Bi2O3/γ-Al2O3 catalysts
Catalytic combustion of methane over Pt and PdO-supported CeO2–ZrO2–Bi2O3/γ-Al2O3 catalysts
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DOI：
10.1007/s10853-011-5333-y
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发表时间：
2011-02
影响因子：
4.5
通讯作者：
K. Yasuda;Toshiyuki Masui;T. Miyamoto;N. Imanaka
中科院分区：
文献类型：
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作者：
K. Yasuda;Toshiyuki Masui;T. Miyamoto;N. Imanaka
以聚乙烯吡咯烷酮（PVP）为催化剂，采用浸渍法制备了Pt和PdO负载的CeO 2-ZrO 2-Bi 2 O3/γ-Al 2 O3催化剂。采用X射线荧光分析、X射线粉末衍射、X射线光电子能谱、透射电子显微镜和BET比表面积等手段对催化剂进行了表征。Pt/CeO 2-ZrO 2-Bi 2 O3/γ-Al 2 O3和PdO/CeO 2-ZrO 2-Bi 2 O3/γ-Al 2 O3催化剂对甲烷完全氧化为CO2和水蒸气具有选择性，且无HCHO、CO和H2等副产物生成。PdO/CeO 2-ZrO 2-Bi 2 O3/γ-Al 2 O3催化剂的催化活性高于Pt负载型催化剂，这是由于CeO 2-ZrO 2-Bi 2 O3体相提供的晶格氧使金属Pd容易再氧化为PdO所致。在制备过程中的煅烧温度的降低被发现是有效的，在提高催化剂的比表面积，从而抑制颗粒团聚。在400 °C下制备的11.6wt%PdO/CeO 2-ZrO 2-Bi 2 O3/γ-Al 2 O3催化剂上，通过优化PdO用量和焙烧温度，甲烷在320 ° C下即可完全氧化。
Catalytic combustion of methane was investigated on Pt and PdO-supported CeO2–ZrO2–Bi2O3/γ-Al2O3catalysts prepared by a wet impregnation method in the presence of polyvinylpyrrolidone. The catalysts were characterized by X-ray fluorescence analysis, X-ray powder diffraction, X-ray photoelectron spectra, transmission electron microscopy, and BET specific surface area measurements. The Pt/CeO2–ZrO2–Bi2O3/γ-Al2O3and PdO/CeO2–ZrO2–Bi2O3/γ-Al2O3catalysts were selective for the total oxidation of methane into carbon dioxide and steam, and no by-products such as HCHO, CO, and H2were obtained. The catalytic activities of the PdO/CeO2–ZrO2–Bi2O3/γ-Al2O3catalysts were relatively higher than those of the Pt-supported catalysts, due to the facile re-oxidation of metallic Pd into PdO based on lattice oxygen supplied from the CeO2–ZrO2–Bi2O3bulk. A decrease in the calcination temperature during the preparation process was found to be effective in enhancing the specific surface area of the catalysts, whereby particle agglomeration was inhibited. Optimization of the PdO amount and calcination temperature enabled complete oxidation of methane at temperatures as low as 320 °C on the 11.6 wt% PdO/CeO2–ZrO2–Bi2O3/γ-Al2O3catalyst prepared at 400 °C.