Patent ID: 8771629

Claim:
A method of producing a nano-carbon material, the method comprising: forming a catalyst-containing nano-carbon material from a granulated catalyst including an active component supported on a carrier; adding oxygen-containing functional groups to the catalyst-containing nano-carbon material, so that the agglomeration of the catalyst-containing nano-carbon material is prevented due to a repulsion among the oxygen-containing functional groups; removing the granulated catalyst from the catalyst-containing nano-carbon material by dissolving the catalyst-containing nano-carbon material in an acid solution, and obtaining an acid-treated nano-carbon material; washing the acid-treated nano-carbon material with water to obtain a washed nano-carbon material in an aqueous solution; adjusting, after the washing, a pH of the aqueous solution to a weakly alkaline side, so that an agglomeration of the washed nano-carbon material is prevented due to an electrostatic repulsion among the oxygen-containing functional groups, at least a part of which has been dissolved in the aqueous solution whose pH is adjusted to the weakly alkaline side; and drying the washed nano-carbon material to obtain the nano-carbon material, wherein the adding oxygen-containing functional groups to the catalyst-containing nano-carbon material is carried out by a physical treatment and/or a chemical treatment, the physical treatment is under an oxygen atmosphere, a heat treatment, a steam oxidation treatment, a plasma treatment, a sputtering treatment, or a discharge treatment and the chemical treatment is a polymer grafting treatment or a surfactant treatment.