Patent ID: 7799308

Claim:
A method for producing a fibrous carbon, the method comprising: disposing a carbon black-supported catalyst in a furnace, wherein the carbon black has a surface area of less than 100 square meters per gram when measured by the Brunauer-Emmett-Teller method, a particle size of 20 to 60 nanometers, and an oxygen content of greater than 10 weight percent, based on the total weight of the carbon black, and wherein the catalyst comprises nickel, and iron or molybdenum, and the catalyst is contained in an amount of 0.1 to 60 weight percent, based on a total weight of the carbon black-supported catalyst; and contacting the carbon black-supported catalyst with a carbon source at a flow rate of 0.5 to 40 standard cubic centimeters per minute per 1 milligram catalyst in the furnace, wherein the carbon source comprises a hydrocarbons containing 2 to 6 carbon atoms or a mixture of hydrocarbons containing 2 to 6 carbon atoms, and hydrogen, to produce a fibrous carbon, the fibrous carbon comprising 95 weight percent carbon, based on the total weight of the fibrous carbon, a diameter of 3.5 to 79.0 nanometers, an aspect ratio of greater than 20, wherein the aspect ratio is a length per diameter, and carbon hexagonal planes, which are aligned perpendicular to a fiber axis, wherein a core of the fibrous carbon is substantially solid.