摘要
分别以碳纳米管（CNTs）和活性氧化铝（Al2O3）为载体，通过浸渍法制备了负载型镍基催化剂和钙改性的镍基催化剂，用二氧化碳甲炕化反应评价其催化性能，通过X射线衍射（XRD）、程序升温还原（H2-TPR）、程序升温脱附（H2-TPD）和氮气等温吸附脱附等手段对催化剂进行表征，结果表明，Ni／CNTs催化剂中的镍物种比Ni／Al2O3中的镍物种容易还原，同时钙改性Ni／CNTs催化剂更能促进镍物种的还原，添加钙可以促进CNTs载体催化剂的分散度，这些特性能提高钙改性Ni／CNTs催化剂的催化活性和稳定性。
Nickel/carbon nanotubes （Ni/CNTs） , Nickel/alumina （Ni/A1203） , calcium-promoted Ni/CNTs and calciumpromoted Ni/A1203 were synthesized by impregnation method. Methanation of carbon dioxide was used as a probe to evaluate their catalytic performance. The features of these Ni-based catalysts were investigated via XRD, HE-TPR, HE-TPD and the N2 adsorption-desorption isotherms. H2-TPR showed that nickel species on Ni/CNTs was reduced more easily with respect to that on Ni/Al2O3, and addition of Ca can increase the content of easily reducible Ni species for Ni/CNTs. XRD and H2-TPD indicated that addition of Ca promoted dispersion for CNTs-supported catalyst. These finding ultimately enhanced catalytic activity and stability for Ni/CNTs catalyst modified with Ca.
关键词
甲烷化
碳纳米管
二氧化碳
镍催化剂
钙
methanation
CNTs
carbon dioxide
nickel catalyst
calcium
