Ceramic foam with gradient of porosity in heterogeneous catalysis

摘要

The invention relates to an architecture comprising ceramic or metallic foam, characterized in that the foam has at least one continuous and/or discontinuous, axial and/or radial porosity gradient ranging from 10 to 90%, and a pore size from 2 ppi to 60 ppi, and in that the architecture has a microstructurc comprising specific area ranging between 0,1 to 30 m 2 /g, a grain size between 100 nm and 20 microns and a skeleton densification above 95%. One process to obtain this architecture can be based on the preparation of a ceramic foam with porosity gradient comprising: choosing at least one polymeric sponge, impregnation of the polymeric sponge by a ceramic slurry, drying of the impregnated sponge, pyrolysing the organics including the polymeric sponge, and sintering, and characterized in that we realize a pre-step to obtain a continuous and/or discontinuous porosity gradient.