Beneficial and problematic interactions between NO sub(x) trapping materials and carbonaceous particulate matter

The presence of a NO sub(x) trapping BaO component with a Pt active phase does not per-se promote carbon combustion. However when coupled with trap regeneration, promotion of soot combustion is seen. Operating NO sub(x) trapping materials promote combustion due to the periodic localised increases in [NO sub(2)] sub((g)) generated during the regeneration rather than due to a co-generated exotherm. However, it has been noted that the presence of soot prevents NO sub(x) traps from employing their full trapping capacity.