Comparative study of Rh/MgO modified with Fe, Co or Ni for the catalytic partial oxidation of methane at short contact time. Part I: Characterization of catalysts
Comparative study of Rh/MgO modified with Fe, Co or Ni for the catalytic partial oxidation of methane at short contact time. Part I: Characterization of catalysts
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DOI：
10.1016/j.apcata.2010.02.017
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发表时间：
2010-04
影响因子：
5.5
通讯作者：
Hisanori Tanaka;Rie Kaino;K. Okumura;T. Kizuka;Y. Nakagawa;K. Tomishige
中科院分区：
文献类型：
--
作者：
Hisanori Tanaka;Rie Kaino;K. Okumura;T. Kizuka;Y. Nakagawa;K. Tomishige
采用程序升温还原（TPR）、H2吸附、透射电镜（TEM）和扩展X射线吸收精细结构（EXAFS）研究了Fe、Co和Ni改性的Rh/MgO催化剂的甲烷部分氧化性能。Rh的存在促进了添加剂（Fe，Co，Ni）在MgO上的还原，还原顺序为Fe>Co>Ni。与Rh/MgO相比，Rh-Ni/MgO倾向于得到具有更高分散度的金属颗粒。相反，向Rh/MgO中添加Fe使金属颗粒聚集。Co的加入对金属颗粒的尺寸没有显著影响。通过Rh K边和M K边EXAFS分析发现了Rh-M合金（M=Fe，Co，Ni）的形成。在EXAFS分析的基础上，讨论了添加剂与Rh的相容性，这种相容性与添加剂在合金颗粒上的表面浓度有关。
Rh/MgO catalysts modified with Fe, Co and Ni for the catalytic partial oxidation of methane were investigated by means of temperature-programmed reduction (TPR), H2adsorption measurement, transmission electron microscopy (TEM) and extended X-ray absorption fine structure studies (EXAFS). The reduction of the additives (Fe, Co, Ni) on MgO was promoted by the presence of Rh, and the reducibility was Fe>Co>Ni. The Rh-Ni/MgO tends to give the metal particles with higher dispersion than Rh/MgO. In contrast, the addition of Fe to Rh/MgO aggregated the metal particles. The Co addition did not affect the size of metal particles so significantly. The Rh–M alloy formation (M=Fe, Co, Ni) was detected by the Rh K-edge and M K-edge EXAFS analyses. The miscibility of the additives with Rh is also discussed on the basis of the EXAFS analysis, and this property can be related to the surface concentration of the additives on the alloy particles.