Patent ID: 7211542

Claim:
A method for producing powdered metal catalyst for use in the production of carbon nanostructures, which method comprises: mixing a) a Group VIII metal compound selected from carbonates, metal nitrates, and metal hydroxides, wherein the Group VIII metal is selected from Fe, Ni and Co, with b) one or more dispersing agents characterized as: i) being substantially inert with respect to reaction with the carbon-containing gas at temperatures up to at least about 750° C.; (ii) being substantially inert with respect to chemical interaction with the catalytic metals at temperatures up to at least about 750° C.; (iii) not having a deleterious effect on the catalytic activity of the catalytic metals; and (iv) capable of maintaining their physical integrity at temperatures up to at least about 750° C., wherein the amount or dispersing agent is from about 5 wt. % to about 25 wt. % based on the total weight of metal compounds and dispersing agents; calcining the resulting mixture at a temperature from about 200° C. to about 400° C. for an effective amount of time to convert at least the metal compound to its respective oxide; milling the calcined mixture for an effective amount of time to decrease the particles comprising the mixture to a predetermined size; treating the milled, calcined mixture of particles with hydrogen for an effective amount of time and temperature to chemically reduce at least a portion of the catalytic metal oxides to the metallic state.