Process for producing catalyst supports or catalyst systems having open pores

Claim 1

A process for producing a solid ceramic catalyst, a solid ceramic-metal catalyst, a solid metal catalyst, a solid ceramic catalytic support, a solid ceramic-metal catalytic support or a solid metal catalytic support, having open interconnecting pores using a framework in the production process which comprises (a) forming a dense agglomeration of spherical bodies of approximately uniform size, said spherical bodies being insoluble bodies having a low melting point or bodies which are soluble in a solvent, and said spherical bodies being capable of being dissolved, evaporated or burned to remove the framework, and (b) connecting together these bodies at their mutual contact points, the initial mutual points of contact of the spherical bodies being enlarged by attachment to each other by means of (i) dissolution, the bodies being connected together by pouring a solvent, which gradually dissolves the material of the spherical bodies, into said dense agglomeration of spherical bodies and by removing said solvent after a short reaction period leaving a film of said solvent on the bodies which forms a fluid meniscus on the contact points of the bodies, (ii) gluing or (iii) sintering into larger areas or surfaces of contact, whereby a framework corresponding in size and arrangement generally to the macropores and pore interconnections of said catalyst metal, said catalyst ceramic, said catalyst ceramic-metal, said catalytic metal support, catalytic ceramic support or said catalytic ceramic-metal support is produced, (c) filling the framework with a suspension containing, as the solid component, said catalyst metal or said catalyst ceramic or said catalyst ceramic-metal or said catalytic support metal or said catalytic support ceramic or said catalytic support ceramic-metal, said framework being prepared from spherical bodies capable of being evaporated or burned substantially below the sintering temperature of said solid component of said suspension used as the framework material, (d) partially or completely hardening said suspension by applying sufficient heat to effect said partial or complete hardening, (e) dissolving away or removing the framework without destroying the structure produced during such partial or complete hardening, said removal of the framework being achieved by applying sufficient heat to evaporate or burn said framework, and (f) if there has been only partial hardening of the cast mass, completely hardening said suspension by applying sufficient heat to effect said complete hardening.