Long-life ceramic catalysts e.g. for use in removing nitric oxides from exhaust gas are stabilized by an (especially oxide) layer, a nanobinder or an activator

摘要

A ceramic carrier is surfaced with a catalyst stabilization layer to suppress migration of the subsequently applied catalyst components, the surface potential of this layer being equivalent to that of the catalyst and the layer being of materials with melting points above the highest use temperature of the carrier. Independent claims are also included for (a) a ceramic catalyst comprising a layer of catalyst components on the surface of a ceramic carrier, this layer containing a material which binds the catalyst components and suppresses their migration, the material having an average primary diameter of 500 nm or less and a melting point higher than the temperature at which the catalyst is used; and (b) a ceramic catalyst having a catalyst component layer on the surface of a ceramic carrier, the layer also including a catalyst activator to introduce hydrogen into the components by a vapor modification reaction, the activator being of a material of melting point above the highest use temperature of the catalyst.