Engine Testing of Catalysts - Conversion Versus Inlet Conditions

A test procedure to determine the conversion performance of oxidation and reduction catalysts for the treatment of automotive engine exhaust gases is described. The variable parameters are the air/fuel ratio, the secondary air quantity and the space velocity.

The results are recorded in diagrams which permit the selection of optimal catalysts with reference to the conversion and which also form the basis for the lay-out of the necessary devices for controlling air/fuel ratio and secondary air.

Characteristic results with noble metal catalysts on monolithic supports and pelleted base metal catalysts are shown.