The operation of an LNT involves two main phases: the trapping phase and the regeneration phase. During the trapping phase, NOx in the exhaust gas is adsorbed onto a catalyst that usually contains a combination of platinum, barium oxide, and other materials. This phase occurs under lean conditions, where there is an excess of oxygen.
In the regeneration phase, which occurs under rich conditions (low oxygen, high hydrocarbons), the adsorbed NOx is released and subsequently reduced to nitrogen (Nâ) and water (HâO) by the catalyst. This dual-phase operation ensures that NOx emissions are minimized even in lean-burn engines.
