Process for the production of high surface area catalyst supports

摘要

Refractory materials which replicate a substantial portion of the internal pore structure as well as the shape and dimensions of high surface area microporous substrate materials which comprise metal or metalloid carbides may be prepared by uniformly depositing a carbide-forming metal or metalloid on the internal surfaces of a high surface area microporous carbon-donor substrate material in the vapor phase. By controlling the operating parameters when depositing carbide-forming metal or metalloid, it is possible to effect a balance between the diffusion rate of the metal or metalloid-containing compound in the structure pores of the substrate with the decomposition rate of the compound, thus obtaining a uniform deposition of the metal or metalloid. If so desired, the substrate material may be subsequently removed by chemical or oxidative means. Examples of high surface area carbon-donor substrate materials which may be employed will include carbonaceous pyropolymers possessing recurring units containing at least carbon and hydrogen atoms per se or composited on a high surface area refractory inorganic oxide such as alumina.