| 摘要 |
PROBLEM TO BE SOLVED: To provide a production method of carbon nanotubes, with which long-sized carbon nanotubes with high crystallinity are efficiently produced by effectively suppressing deactivation of a catalyst, even when acetylene of high concentration is fed.SOLUTION: In a production method of carbon nanotubes, acetylene, a catalyst for generating carbon nanotubes from the acetylene, and a support medium to carry the catalyst are used, and carbon nanotubes are synthesized on the support medium while heating the support medium in a fluidized-bed reactor. The production method of carbon nanotubes has a synthesizing step to synthesize carbon nanotubes on the support medium by feeding a raw material gas including acetylene, carbon dioxide, and a carrier gas into the fluidized-bed reactor with a linear flow rate of 10 cm/s or more, in which concentration of acetylene in the raw material gas is less than 5 vol.%, and concentration of carbon dioxide is 0.1 vol.% or more and less than 40 vol.%.SELECTED DRAWING: Figure 1 |
