Few Walled Carbon Nanotube Production in Large-Scale by Nano-Agglomerate Fluidized-Bed Process

Abstract

Few walled carbon nanotubes (FWCNTs) have been successfully synthesized using a nanoagglomerate fluidized-bed process. FWCNTs can be obtained by fluidization of Fe(Co/Ni)/Mo/ MgO catalysts at a high temperature with methane cracking in a nano-agglomerate fluidizedbed reactor. The products were mainly 2 to 5 walled CNTs with an outer diameter of 1-7 nm in high purity, as revealed by Raman spectrometry, SEM, and HRTEM analysis. Two keys were crucial for this process. The first key was to get the small size of activity catalyst particles which was realized by Mo addition in catalyst. The graphitization of FWCNTs strongly depended on the composition of catalyst. Fe/Mo/MgO catalyst showed the highest activity and the FWCNT product with the best graphitization. Another key for this process was that the particles must be kept in fluidized state during FWCNT formation. Detailed process information was reported in this article, which showed a potential way for the large scale production of FWCNTs, thereby the urgent need for FWCNTs in high performance will be overcome. Keywords: Few walled carbon nanotube; fluidized bed; large scale. 45 NANO 2008.03:45-50. Downloaded from www.worldscientific.com by FUDAN UNIVERSITY on 05/14/15. For personal use only.

Enhanced Methanation over Aerogel NiCo/Al2O3Catalyst in a Magnetic Fluidized Bed

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