Selective methanation of CO in H2-rich gas stream by synthetic nickel-containing smectite based catalysts
Selective methanation of CO in H2-rich gas stream by synthetic nickel-containing smectite based catalysts
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DOI：
10.1016/j.apcatb.2014.06.029
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发表时间：
2015
影响因子：
22.1
通讯作者：
H. Yoshida;Kou Watanabe;N. Iwasa;S. Fujita;M. Arai
中科院分区：
文献类型：
--
作者：
H. Yoshida;Kou Watanabe;N. Iwasa;S. Fujita;M. Arai
本文研究了含镍蒙脱石（SM（Ni））催化剂和传统的SiO_2、Al_2O_3、ZrO_2和MgO负载的Ni催化剂在富H_2气流中的CO选择性甲烷化反应。SM（Ni）中的镍含量和其它催化剂中的镍负载量相同，为35重量%。在150-300 °C的温度下，SM（Ni）的CO转化率小于常规负载型镍催化剂。然而，与后一种催化剂相比，前者在250 °C或更低温度下显示出>95%的CO甲烷化选择性。SM（Ni）的低活性归因于暴露的镍物种的小面积。通过在SM（Ni）中掺杂还原促进剂Pt，提高了Ni物种的暴露面积，在保持CO甲烷化高选择性的同时，提高了活性。考察了还原温度和铂负载量对催化剂活性和选择性的影响。
The selective methanation of CO in a H2-rich gas stream has been investigated with nickel catalysts including synthetic nickel-containing smectite (SM(Ni)) catalysts undoped and doped with platinum in small quantities and conventional nickel catalysts on SiO2, Al2O3, ZrO2, and MgO. The nickel content in SM(Ni) and the nickel loading in the other catalysts were the same, being 35 wt.%. The CO conversion with SM(Ni) was smaller than those with the conventional supported nickel catalysts at temperatures of 150–300 °C. However, the former showed the higher selectivity to the methanation of CO of >95% at 250 °C or below compared to the latter catalysts. The low activity of SM(Ni) was ascribed to a small area of exposed nickel species. The area of exposed nickel species was improved by doping a reduction promoter of platinum to SM(Ni), resulting in an increase in the activity while keeping the high selectivity to the CO methanation. The influence of reduction temperature and platinum loading on the activity and selectivity was investigated.