掺杂Cu的Ni基催化剂用于制备碳纳米管

Preparation of Carbon Nanotubes on Nickel-Based Catalyst Doping with Copper

以共浸渍法制备的Ni-Cu-Al金属复合物为催化剂,甲烷高温裂解合成碳纳米管。考察了Cu含量对Ni-Cu-Al催化剂活性和碳纳米管形貌的影响及焙烧温度和焙烧气氛对Ni-Cu-Al催化剂性能的影响。采用透射电子显微镜对Ni-Cu-Al催化剂和碳纳米管的形貌进行了表征,采用程序升温还原方法考察了Ni-Cu-Al催化剂的还原温度。实验结果表明,在Ni-Al催化剂中加入Cu不仅可提高催化剂的活性、延长催化剂的寿命,还有助于控制生成的碳纳米管的内径。当n(Ni)∶n(Cu)∶n(Al)=75∶15∶10时,Ni-Cu-Al催化剂的BET比表面积最大,为278.18m2/g;活性也最高,在甲烷流量60mL/min、反应温度1023K、反应时间300min的条件下,碳纳米管的收率(以催化剂的质量计)为23.66g。Ni-Cu-Al催化剂的最佳焙烧条件为350℃,氮气气氛。

Carbon nanotubes （CNTs）were synthesized by catalytic cracking of methane at high temperature on Ni-Cu-Al catalysts prepared by co-impregnation. The catalysts and the obtained CNTs were characterized by means of TEM and TPR. Effects of Cu contents and preparation conditions on activities of Ni-Cu-Al catalysts were investigated. Cu can influence both catalytic activity and life of Ni-Cu-Al catalysts, and can adjust inner diameter of CNTs. BET specific surface area of the catalyst can reach max. （278.18 m^2/g）and its activity is the highest when n（Ni） ： n（Cu） ： n（Al）in Ni-Cu-AI catalyst is 75 ： 15 ： 10. Under optimal conditions：methane flow rate 60 mL/min, reaction temperature 1023 K, reaction time 300 min and Ni-Cu-Al catalyst prepared under nitrogen at 350℃, yield of CNTs （based on catalyst mass）can reach 23.66 g.