Synthesis and characterization of multiwall carbon nanotubes/alumina nanohybrid-supported cobalt catalyst in Fischer-Tropsch synthesis  

作　　者：Ali Karimi Bahram Nasernejad Ali Morad Rashidi 

机构地区：[1]Chemical Engineering Department,Amir Kabir University of Technology [2]Nanotechnology Research Center,Research Institute of Petroleum Industry

出　　处：《Journal of Energy Chemistry》2013年第4期582-590,共9页能源化学（英文版）

基　　金：supported by the Research Council of the Research Institute of Petroleum Industry;the Research and Development of the National Iranian Oil Company

摘　　要：Multiwall carbon nanotubes （MWNTs） and alumina are combined to give a new type of nanohybrid for Fisher-Tropsch synthesis （FTS） catalyst support. Alumina nano-particles （10 wt%） were introduced directly on functionalized MWNTs by a modified sol-gel method. Microstructure observations show that alumina particles were homogeneously dispersed on the inside and outside of modified MWNTs surfaces. 15 wt% cobalt loading catalysts were prepared with this nanohybrid and γ-alumina as a reference, using a sol-gel technique and wet impregnation method respectively. These catalysts were characterized by TEM, XRD, N2-adsorption, H2 chemisorption and TPR. The deposition of cobalt nanoparticles synthesized by sol-gel technique on the MWNTs nanohybrid shift the reduction peaks to a low temperature, indicating higher reducibility for uniform cobalt particles. Nanohybrid also aided in high dispersion of metal clusters and high stability and performance of catalyst. The proposed MWNTs nanohybrid-supported cobalt catalysts showed the improved FTS rate （gHc/（gcat.min））, CO conversion （%）, and water gas shift rate （WGS）（gcoz/（gcat.h）） of 0.012, 52, and 30E-3, respectively, as compared to those of 0.007, 25, and 18E-3, respectively, on the γ-alumina-supported cobalt catalysts with the same Co loading.Multiwall carbon nanotubes （MWNTs） and alumina are combined to give a new type of nanohybrid for Fisher-Tropsch synthesis （FTS） catalyst support. Alumina nano-particles （10 wt%） were introduced directly on functionalized MWNTs by a modified sol-gel method. Microstructure observations show that alumina particles were homogeneously dispersed on the inside and outside of modified MWNTs surfaces. 15 wt% cobalt loading catalysts were prepared with this nanohybrid and γ-alumina as a reference, using a sol-gel technique and wet impregnation method respectively. These catalysts were characterized by TEM, XRD, N2-adsorption, H2 chemisorption and TPR. The deposition of cobalt nanoparticles synthesized by sol-gel technique on the MWNTs nanohybrid shift the reduction peaks to a low temperature, indicating higher reducibility for uniform cobalt particles. Nanohybrid also aided in high dispersion of metal clusters and high stability and performance of catalyst. The proposed MWNTs nanohybrid-supported cobalt catalysts showed the improved FTS rate （gHc/（gcat.min））, CO conversion （%）, and water gas shift rate （WGS）（gcoz/（gcat.h）） of 0.012, 52, and 30E-3, respectively, as compared to those of 0.007, 25, and 18E-3, respectively, on the γ-alumina-supported cobalt catalysts with the same Co loading.

关 键 词：carbon nanotubes NANOHYBRID cobalt catalyst ALUMINA FT synthesis SOL-GEL 

分 类 号：O643.36[理学—物理化学] TB383.1[理学—化学]