| abstract |
A filter for filtering particulate matter (PM) from exhaust gas discharged from a compression ignition engine, the filter comprising a porous substrate having an inlet surface and an outlet surface, the inlet surface containing pores of a first average pore size And the porous substrate is coated with a washcoat comprising a plurality of solid particles comprising molecular sieves promoted with at least one metal, and the porous structure of the washcoated porous substrate is formed. A filter having two average pore sizes, wherein the second average pore size is less than the first average pore size. |