Specific performance of silica-coated Ni catalysts for the partial oxidation of methane to synthesis gas
Specific performance of silica-coated Ni catalysts for the partial oxidation of methane to synthesis gas
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DOI：
10.1016/j.jcat.2006.11.005
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发表时间：
2007-01
影响因子：
7.3
通讯作者：
S. Takenaka;Hiroshi Umebayashi;E. Tanabe;H. Matsune;M. Kishida
中科院分区：
文献类型：
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作者：
S. Takenaka;Hiroshi Umebayashi;E. Tanabe;H. Matsune;M. Kishida
采用油包水型微乳液法制备了二氧化硅负载镍催化剂。采用微乳液法制备了粒径< ca. 5 nm的表面均匀地覆盖有厚度约为1.5nm的二氧化硅层。10 nm，而Ni金属颗粒通过常规浸渍方法负载在二氧化硅的外表面上。在甲烷部分氧化制合成气反应中，二氧化硅包覆的镍金属（涂层镍）表现出了优异的催化性能。Coat-Ni催化剂在973 K以上的温度下甲烷部分氧化生成CO和氢气时表现出高活性和长寿命，而负载在SiO2上的Ni金属催化剂在该反应中很快失活。Ni-K边XANES/EXAFS和程序升温还原研究表明，Ni包覆层中的Ni金属颗粒与SiO2有较强的相互作用。Ni金属颗粒与SiO2的强相互作用将提高其对甲烷部分氧化制合成气的催化性能。
Silica-supported Ni catalysts were prepared by using water-in-oil typed microemulsion. By preparation using the microemulsion, Ni metal particles with diameters < ca. 5 nm were covered uniformly with silica layers with thickness of ca. 10 nm, whereas Ni metal particles were supported on the outer surface of silica by a conventional impregnation method. The Ni metal covered with silica (coat-Ni) showed excellent catalytic performance for the partial oxidation of methane into synthesis gas. Coat-Ni showed a high activity and a long life for the partial oxidation of methane at temperatures above 973 K to form CO and hydrogen, whereas Ni metal catalyst supported on silica was rapidly deactivated for the reaction. Ni K-edge XANES/EXAFS and temperature-programmed reduction for these catalysts showed that Ni metal particles in coat-Ni strongly interacted with silica. The strong interaction of Ni metal particles with silica would improve their catalytic performance for the partial oxidation of methane into synthesis gas.