LNT and SCR based NOx aftertreatment systems for the North American diesel market

Ulrich  Goebel, Umicore AG & Co. KG

The increasingly more stringent North American Tier 2 standards generate a need for more effective exhaust gas aftertreatment systems. With respect to Diesel aftertreatment, a NOx control with 65-80% efficiency, as well as an efficient particle control is in the main focus of the system development.
The present contribution concentrates on the discussion of aftertreatment systems based on Lean NOx Traps (LNT) and SCR catalysts as key system components for efficient NOx control. Strategies for using synergies between these two devices are emphasized.
Important research aspects are reported and critical boundary conditions for the successful implementation and system integration are discussed.