SCR-Catalyzed Diesel Particulate Filter (SDPF)
Besides the application on a conventional flow-through substrate, SCR technology can also be coated on a wall-flow filter substrate.
The corresponding technology is called SDPF and controls both nitrous oxides (NOx) and particulate matter (PM). It additionally offers also the opportunity for a close coupled application, whereas SCR catalysts are typically used in an underfloor position.
For a successful SDPF application, an important prerequisite to guarantee an optimum performance (NO, particulate mass and number) with lowest possible backpressure, is the use of highly porous substrates in combination with the precise distribution of catalytically active components.