物理化学学报 >> 1996, Vol. 12 >> Issue (11): 990-994.doi: 10.3866/PKU.WHXB19961107

研究论文 上一篇    下一篇

氧化铈对F-T反应铁锆催化剂的助催化作用

陈开东,颜其洁   

  1. 南京大学化学系,南京 210093
  • 收稿日期:1996-06-24 修回日期:1996-09-02 发布日期:1996-11-15
  • 通讯作者: 颜其洁

Influence of Ceria on the Structure and Catalytic Property of F-T Synthesis Fe/ZrO2 Catalysts

Chen Kai-Dong,Yan Qi-Jie   

  1. Department of Chemistry,Nanjing University,Nanjing 210093
  • Received:1996-06-24 Revised:1996-09-02 Published:1996-11-15
  • Contact: Yan Qi-Jie

摘要:

应用XRD、XPS、Mossbauer谱、TPR、CO-TPD、CO+H2反应性能测试等手段研究了CeO2对F-T合成制低碳烯烃Ce-Fe/ZrO2催化剂结构及催化性能的影响. 结果表明,与Fe/Zr催化剂相比,加铈助剂后的催化剂F-T反应催化活性明显上升,甲烷选择性降低,低碳烯烃选择性增加,随铈含量的增加,催化剂的烯烃选择性增加.

关键词: CO加氢, 低碳烯烃, 铁锆催化剂, 铈助剂

Abstract:

Ceria promoted Fe/ZrO2 catalysts were prepared by different impregnation methods. The structure, reduction behavior, CO desorption behavior, and catalytic property of various catalysts were studied by XRD, Mossbauer spectroscopy, TPR, XPS, CO-TPD, and CO hydrogenation reaction test. It is shown that the catalytic activity of ceria promoted Fe/ZrO2 catalysts is much higher than that of the unpromoted Fe/Zr sample, while methane formation is suppressed and light olefins selectivity slightly increases. The different catalyst preparation methods affect the structure and reduction behavior of Ce-Fe/ZrO2 catalysts, but do not obviously influence the catalytic properties for CO hydrogenation. The promotion effect of ceria can be explained in terms of the formation of new catalytic active sites (Fe-CeO2 ensembles) at which CO may bond with its carbon atom to iron atom and its oxygen atom to the partially reduced cerium oxide. This results in a wakening of the C-O bond, and the dissociation and reaction of CO is markedly enhanced. 

Key words: CO hydrogenation, Light olefins, Fe/ZrO2 catalyst, Ceria promoter