碳纳米管助剂对费托合成用氧化铝担载纳米钴基催化剂的影响

Effect of carbon nanotubes on alumina-supported cobalt catalyst for Fischer-Tropsch synthesis

以碳纳米管(CNTs)为助剂制备了碳纳米管促进的氧化铝担载钴费托合成催化剂,采用程序升温,N2物理吸附、X射线衍射以及氢氧滴定等表征技术对催化剂进行了表征,并考察了碳纳米管添加对一氧化碳加氢催化性能的影响。表征结果表明,催化剂引入碳纳米管助剂调变了活性组分钴和载体之间的相互作用并改善了钴物种的还原性能,但对钴基催化剂活性组分平均粒径和分散度没有显著影响。费托合成反应结果表明,随着碳纳米管助剂的添加,催化剂活性降低,C5+选择性却大大提高。

Carbon nanotubes promoted alumina-supported cobalt Fischer-Tropsch catalysts were prepared and characterized by N2 adsorption,temperature-programmed reduction,temperature-programmed hydrogenation reaction（TPCOH）,X-ray diffraction（XRD）,and temperature-programmed desorption of H2.It was found that introducing CNTs into the catalyst modified the interaction between cobalt and alumina and improved the reducibility of cobalt species,however,had no significant influences on cobalt particle size and its dispersion.The results of CO hydrogenation showed that the existence of CNTs enhanced the selectivity of long chain hydrocarbons,but had no effect on the catalytic activity.