Understanding NH3 Formation over Lean NOx Trap (LNT) Catalysts: Effects of Lean/Rich Cycle Timing and Temperature

The impact of LNT lean/rich cycle timing and reductant concentration on NOx conversion and NH₃/N₂O/N₂ was studied over a commercially-available catalyst.  Below 250°C, long rich times with low reductant concentrations were preferred; the opposite is true above 450°C.  NH₃ yield peaks at 250°C (50%), but so does N₂O yield (10%).