SCR catalyzed soot filter with integrated lean NOx trap catalyst for use in passive selective catalytic reduction

摘要

The present invention is a catalyzed soot filter (CSF), the CSF comprising a porous wall flow substrate, a lean NOx trap (LNT) catalyst, and a catalyst for selective catalytic reduction (SCR), wherein the wall The flow substrate includes an inlet end, an outlet end, a substrate axial length extending between the inlet end and the outlet end, and a plurality of channels defined by an inner wall of the wall flow substrate, the plurality of channels The channel includes an inlet channel having an open inlet end and a closed outlet end, and an outlet channel having a closed inlet end and an open outlet end, wherein the LNT catalyst is a portion of the surface of the inlet channel wall, and the LNT catalyst. A portion of the inlet channel wall coated with the LNT catalyst is supplied to at least a portion of the surface of the pores in the channel wall below the surface of the coated channel wall, Extending from the mouth end to x% of the substrate axial length (0 x 100), the SCR catalyst is part of the surface of the outlet channel wall and the channel coated with the SCR catalyst A portion of the outlet channel wall supplied to at least a portion of the surface of the pore in the channel wall below the surface of the wall and coated with the SCR catalyst has a length of 100 in the substrate axial direction from the outlet end. Exhaust gas using the catalyzed soot filter in an exhaust gas treatment system including the catalyzed soot filter in a catalyzed soot filter extending to -x% and in a method of manufacturing the catalyzed soot filter Relates to a method of treatment and to the use of the catalyzed soot filter for the treatment of the exhaust gas.