The impending global regulations on emissions present substantial challenges for modern diesel engines and aftertreatment technology, particularly in the control of NOx and CO2 emissions. Generally, diesel fuel produces more energy for a given volume comparatively higher than other fuel like Petrol. But in general diesel engines operate at a higher temperature and pressure than petrol engines. These conditions offer favour the production and emission of NOx gases in atmosphere.

One technical solution on the aftertreatment side is the combination of Lean NOx Trap (LNT) system and Selective Catalytic Reduction (SCR).

• LNT system removes the nitrogen oxide in the exhaust gas.
• SCR system is one of the advanced exhausts after treatment system to reduce NOx.

One main functionality of the combined concept of NSC- oxidation catalyst and passive SCR is the NH3 (Ammonia) formation on the NSC during the rich NSC regeneration.

The formed NH3, the NOx conversion can be enhanced by a downstream positioned SCR. The SCR is passively operated and does not require additional second working fluid like AdBlue (liquid urea).