Catalytic converter with improved start-up behaviour

Abstract

In automotive exhaust gas catalysts with a metallic honeycomb composed of corrugated and smooth sheet layers, it is known that the heat capacity and thermal conductivity of the honeycomb can be reduced by perforations in the sheet layers. As a result, the honeycomb heats up more rapidly and the catalytic coating applied on the honeycomb reaches its operating temperature more rapidly. A disadvantage here is the reduction in the support surface area by the perforations in the sheet layers. According to the invention, suitable adjustment of the properties of the coating suspension used for the catalytic coating and of the dimensions of the holes relative to one another allows the holes to be filled permanently with catalyst material. The resulting catalyst has, at the same coating concentration as a catalyst with unperforated sheet layers, a significantly reduced heat capacity and thermal conductivity.

Dependencies are inferred from the claim text.