A fluidized bed reactor is employed to prepare carbon nanotubes. The carbon nanotubes are characterized by means of SEM and TEM. Using LaCoO 3 as catalyst precursor and C 2H 2 as raw material, we study the influences of various parameters such as reduction temperature, reduction time, reaction temperature and reaction time on the yield and morphology of the nanotubes. The results indicate that the optimum conditions are: reduction temperature of 650 ℃ and reaction temperature of 675 ℃.
In the present work, Ni Ce catalyst was used for the preparation of carbon nanotubes(CNTs) in the atmosphere of partial oxidation of methane(POM). Mainly growing on quartz wool or wall of reactor, the bulk CNTs were obtained. Probably CNTs were synthesized by two routes due to the typical reaction conditions of POM. One was that CNTs were produced from the decomposition of CH 4 on the Ni particles. After transported out of the catalyst zone by blowing of feedgas, CNTs adhered to quartz wool or the wall of reactor. Predominately, the other way was that firstly syngas was produced from POM reaction and then CNTs grew from disproportionation of CO in presence of hydrogen. A little remaining oxygen in effluent could remove the other morphologic carbon, so CNTs were easily opened and purified at the same time of growth. This research maybe arouse us to assemble the continuous process of POM and preparation of CNTs. CNTs were applied to be negative materials for lithium battery. The reversible electrical capacity of simulative lithium battery can be increased ca. 20% with adding 10%(in mass fraction) carbon nanotubes into natural graphite. [WT5HZ]
