Reactor design for the evaluation of diesel oxidation catalysts supported by sintered metal filters

This paper addresses the design of a novel laboratory bench for the practical evaluation of diesel oxidation catalysts (DOC) coated onto porous sintered metal filters (SMF). Such catalytic systems combine oxidation and filtration functionality in one process stage to remove hydrocarbons, carbon monoxide and soot from the exhaust of diesel engines. A unique feature of the bench is the reactor unit in which the used DOC-SMF disc (diameter: 30 mm) is reliably sealed by a special configuration of metal rings. The designing of the reactor was supported by computational fluid dynamics showing that the temperature profile at the metal substrate is almost isothermal under typical test conditions. The suitability of the laboratory reactor was demonstrated by practical evaluation of a DOC-SMF sheet providing plausible performance upon oxidation of propene, carbon monoxide and nitric oxide. Furthermore, it was shown that the catalytic efficiency of the DOC-SMF disc was not affected by pore and film diffusion, respectively.