Surface chemistry improvement of carbon nanotube (CNT) supported Fischer–Tropsch nanocatalysts
محورهای موضوعی : Journal of NanoanalysisAli Karimi 1 , Ahmad Tavasoli 2 , Maryam Davari 3 , Ali Mohajeri 4
1 - Gas research Division, Research Institute of Petroleum Industry, Tehran, Iran
2 - School of Chemistry, College of Science, University of Tehran, Tehran, Iran
3 - School of Chemistry, College of Science, University of Tehran, Tehran, Iran
4 - Gas research Division, Research Institute of Petroleum Industry, Tehran, Iran
کلید واژه: Stability, Carbon nanotubes, Functionalization, Fischer–Tropsch, Activity,
چکیده مقاله :
Functionalization of carbon nanotube (CNT) was performed, during preparation of Fischer–Tropsch synthesis (FTS) via cobalt nanocatalysts, to modify the surface properties of CNT support. Common and functionalized CNT supported cobalt nanocatalysts were prepared using impregnation wetness method with cobalt loading of 15 wt.%. The catalysts were characterized by Brunauer–Emmett–Teller (BET), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), temperature program reduction (TPR), H2 chemisorption, and transmission electron microscopy (TEM) technique. Most of the cobalt particles were homogeneously distributed inside the tubes and the rest on the outer surface of the functionalized CNT. Functionalization of CNT shifted the TPR reduction peaks to lower temperatures, improved the reduction degree, and increased the dispersion of cobalt particles and stability of catalysts. The proposed cobalt catalyst supported on functionalized CNT- (N-doped functionalized CNT) increased the FTS rate (g HC/gcat./hr), and CO conversion (%) from 0.1347, and 30 to 0.235, and 47 respectively, compared to that of the catalyst prepared by impregnation wetness method on common CNT. Catalysts supported on functionalized CNT also showed better stability.