PREPARATION OF HYDROGEN AND CARBON NANOTUBES via METHANE DECOMPOSITION IN FLUIDIZED-BED REACTOR
Preparation of carbon nanotubes and hydrogen from methane decomposition over a nano sized Ni/Cu/Al 2O 3 catalyst was investigated in the temperature range of 823-1143 K in a fluidized bed reactor, which can provide sufficient space for carbon nanotubes growth It was observed that the conversion of methane directly depended on operation conditions,including temperature,space velocity, gas velocity and the heat up rate etc Also the morphology of nanotubes was influenced significantly by the heat up mode Adopting a lower heat up rate (50K·h -1 ), relatively high conversion of methane and carbon nanotubes with pretty good morphology can be simultaneously achieved as compared to the results by adopting a higher heat up rate(600K·h -1 ) Furthermore, by using a low heat up rate from 823K to 1123K,continuous production of the carbon nanotubes was achieved at 1123K and the yield of carbon nanotubes was up to 10g·(g cat) -1 ·h -1 , which provided the basis for the large scale and continuous production of carbon nanotubes