Patent ID: 8192714

Claim:
A method for manufacturing carbon nanotubes comprising the steps of: preparing at least one metal selected from a group consisting of iron, cobalt and nickel and an organic compound; and forming carbon nanotubes by using the organic compound as a carbon source, wherein the metal and the organic compound are put into a heating vessel having a substance capable of converting electromagnetic energy into heat, and the organic compound is brought into contact with the metal in a state where the inside of the heating vessel is heated at a temperature of 600° C. to 900° C. by applying the electromagnetic energy to the heating vessel so as to form the carbon nanotubes; wherein the method further comprises a step of putting the metal and the organic compound into a reaction vessel in a state where the metal and the organic compound are separated from each other between the step of preparing the metal and the organic compound and the step of forming the carbon nanotubes; in the step of forming the carbon nanotubes, the organic compound is brought into contact with the metal in the inside of the reaction vessel; wherein in the step of forming the carbon nanotubes, the reaction vessel is placed in the inside of the heating vessel and, thereafter, the electromagnetic energy is applied to the heating vessel so as to heat the inside of the heating vessel at a temperature of 600° C. to 900° C.; and wherein the substance capable of converting electromagnetic energy into heat is at least one selected from a group of substances consisting of a alumina, mullite, ferrite, silicon nitride and silicon carbide.