A thin-walled honeycomb body (100) having a plurality of repeating cell structures (110) formed of intersecting porous thick walls (112V, 112H) and thin walls (114V, 114H). Each repeating cell structure (110) is bounded on its periphery by the thick walls (112V, 122H) of a first transverse thickness (Tk) and the thin walls (114V, 114H) have a second transverse thickness (Tt) that subdivides each repeating cell structure (110) into between 7 and 36 individual cells (108). In the thin-walled honeycomb body (100), the first transverse thickness (Tk) of the thick walls (112V, 112H) is less than or equal to 0.127 mm (0.005 inch) and the second transverse thickness (Tt) of the thin walls (114V, 114H) is less than or equal to 0.0635 mm (0.0025 inch), and Tk>Tt. Honeycomb extrusion dies and methods of manufacturing the thin-walled honeycomb body (100) having thick walls (112V, 112H) and thin walls (114V, 114H) are provided.

Catalyzed particulate filters comprise three-way conversion (TWC) catalytic material that permeates walls of a particulate filter such that the catalyzed particulate filter has a coated porosity that is less than an uncoated porosity of the particulate filter. The coated porosity is linearly proportional to a washcoat loading of the TWC catalytic material. A coated backpressure is non-detrimental to performance of the engine. Such catalyzed particulate filters may be used in an emission treatment system downstream of a gasoline direct injection engine for treatment of an exhaust stream comprising hydrocarbons, carbon monoxide, nitrogen oxides, and particulates.

An exhaust gas purification catalyst (C), including a three-dimensional structure (10) and a catalyst component layer (20) supported on the three-dimensional structure (10), where the average thickness of the catalyst component layer (20) is 15 μm or more to 200 μm or less, the average particle size of the catalyst component is 2 μm or more to 10 μm or less, and the catalyst component particle size variation coefficient is 10 or more and less than 50. The particle distribution of the catalyst component can be 90% or more to 99.9% or less.

The invention relates to a particulate filter for removing particles, carbon monoxide, hydrocarbons and nitrogen oxides out of the exhaust gas of combustion engines operated with stoichiometric air/fuel mixture, comprising a wall flow filter with length L and a coating Z, wherein the wall flow filter includes channels E and A which extend in parallel between a first and a second end of the wall flow filter and are separated by porous walls, which form surfaces OE or OA, and wherein the channels E are closed at the second end and the channels A are closed at the first end, characterised in that coating Z is located in the porous walls and extends from the first end of the wall flow filter over the entire length L, and includes active aluminum oxide, two different cerium/zirconium/rare earth metal mixed oxides and at least one platinum group metal.

A lean NO.sub.x trap catalyst and its use in an emission treatment system for internal combustion engines is disclosed. The lean NO.sub.x trap catalyst comprises a first layer for storing nitrogen oxides (NOx) under lean exhaust gas conditions and releasing and/or reducing stored NOx during rich exhaust gas conditions, and a second layer, said second layer comprising a first zone for oxidizing carbon monoxide (CO) and/or hydrocarbons (HC), and a second zone for oxidizing nitric oxide (NO), and a substrate having an inlet end and an outlet end.

A ceramic honeycomb body, suitable for use in exhaust gas processing, includes a honeycomb structure having a plurality of through-channels, a first portion of the plurality of through-channels have a first hydraulic diameter dh1, a second portion of the plurality of through-channels have a second hydraulic diameter that is smaller than the first hydraulic diameter dh1, the first hydraulic diameter dh1 is equal to or greater than 1.1 mm, and the first and second portions of through-channels, taken together, have a geometric surface area GSA greater than 2.9 mm.sup.−1. Diesel oxidation catalysts and methods of soot removal are also provided, as are other aspects.

A cordierite-containing ceramic body with % P≥50%, df≤0.50, and a combined weight percentage of crystalline phases containing cordierite and indialite of at least 85 wt %. The porous ceramic body contains, as expressed on a relative oxide weight percent basis in terms of MgO, Al.sub.2O.sub.3, and SiO.sub.2 that is within a field defined by (15.4, 34.1, and 50.5), (12.2, 34.1, and 53.7), (13.3, 31.2, and 55.5), and (16.6, 31.1, and 52.3). Batch composition mixtures and methods of manufacturing a porous ceramic body using the batch compositions are provided, as are other aspects.

The present disclosure provides catalyst compositions for NO.sub.x conversion and wall-flow filter substrates comprising such catalyst compositions. Certain catalyst compositions include a zeolite with sufficient Cu exchanged into cation sites thereof to give a Cu/Al ratio of 0.1 to 0.5 and a CuO loading of 1 to 15 wt. %; and a copper trapping component (e.g., alumina) including a plurality of particles having a D.sub.90 particle size of about 0.5 to 20 microns in a concentration of about 1 to 20 wt. %. The zeolite and copper trapping component can be in the same washcoat layer or can be in different washcoat layers (such that the copper trapping component serves as a “pre-coating” on the wall-flow filter substrate).

A honeycomb body having intersecting porous walls which includes first through fourth cells, wherein the cells extend from inlet to outlet face and are plugged to define a repeating structural unit with three inlets and one outlet channel. Repeating structural unit includes a first channel including length L.sub.1, width W.sub.2, and area A.sub.1, a second channel including length L.sub.2, the width W.sub.2, and area A.sub.2, a third channel including the length L.sub.1, width W.sub.1, and area A.sub.3, and a fourth channel including the length L.sub.2, the width W.sub.1, and A.sub.4, wherein the first through third channels are inlets and the fourth channel is a rectangular outlet and at least one of W.sub.1≥W.sub.2 and L.sub.1≠L.sub.2, i.e. W.sub.1≥W.sub.2, or L.sub.1≠L.sub.2, or W.sub.1≥W.sub.2 and L.sub.1≠L.sub.2. Repeating structural unit has a quadrilateral outer perimeter. Particulate filters including the honeycomb body, honeycomb extrusion dies, and methods of manufacturing the honeycomb body are provided.

Disclosed is a honeycomb filter for collecting fine particles that includes a wall portion formed from a base material containing ceria-zirconia composite oxide and an inorganic binder. The wall portion has a gas permeability coefficient of 1.0 μm.sup.2 or greater and 3.0 μm.sup.2 or less.