Combining oxi-cat with Lightly-Catalyzed Soot Filter improves low-temp performance, cuts cost

Diesel Fuel News, March 18, 2002

Johnson-Matthey reports that a new oxi-cat/CSF combo (SAE 2002-01-0428) can cut precious metal requirements and still improve low-temperature soot regeneration (down to 250[degree]C), while minimizing [NO.sub.2] slip with an optimized formulation. This is in contrast with JM's typical "CRT" scheme, which uses an uncatalyzed filter downstream of a relatively hefty-PGM loaded oxi-cat.

The new formulation, with half the PGM load in the oxi-cat, should favor low-temp duty cycles as often seen with garbage trucks, city-center buses and similar applications, JM's Andy Walker explained here.