The present invention relates to a wall flow filter, to a method for the production and the use of the filter for reducing harmful exhaust gases of an internal combustion engine. Particle filters are commonly used for filtering exhaust gases from a combustion process. Also disclosed are novel filter substrates and their specific use in exhaust gas aftertreatment.

A substrate (11) of an exhaust gas purification catalyst (10) includes inflow-side cells (21), outflow-side cells (22), and porous partition walls (23), each separating the inflow-side cell and the outflow-side cell. Catalyst portions (14, 15) are provided on the surfaces of the partition walls that each face the inflow-side cell and/or the surfaces of the partition walls that each face the outflow-side cell. In a cross section vertical to an exhaust gas flow direction, the percentage of the total area of voids, each void satisfying the expression L/{2(πS).sup.1/2}≤1.1 (wherein L is the perimeter of the void in the cross section, and S is the area of the void in the cross section), is greater than 10% to 30% or less based on the apparent area of the catalyst portion present on the partition wall. The content of zirconium element in terms of oxide (amount of ZrO.sub.2) in the catalyst portions is from 35 mass % to 85 mass %.

A compression ignition internal combustion engine (30) for a heavy-duty diesel vehicle comprising an exhaust system (32) comprising a composite oxidation catalyst (12, 42) and a soot filter substrate (44, 50) disposed downstream from the composite oxidation catalyst comprising: a substrate (5), preferably a honeycomb flow-through substrate monolith, having a total length L and a longitudinal axis and having a substrate surface extending axially between a first substrate end (I) and a second substrate end (O); two catalyst washcoat zones (1, 2) arranged axially in series on and along the substrate surface, wherein a first catalyst washcoat zone (1) having a length L.sub.1 and comprising a first catalyst washcoat layer (9), wherein L.sub.1<L, is defined at one end by the first substrate end (I) and at a second end by a first end (15) of a second catalyst washcoat zone (2) having a length L.sub.2 and comprising a second catalyst washcoat layer (11), wherein L.sub.2<L, wherein the second catalyst washcoat zone (2) is defined at a second end thereof by the second substrate end (O), and wherein the first substrate end (I) of the composite oxidation catalyst (12, 42) is oriented to an upstream side and wherein the first catalyst washcoat zone (1) comprises a first refractory metal oxide support material and two or more platinum group metal components supported thereon comprising both platinum and palladium at a weight ratio of platinum to palladium of <1; and the second catalyst washcoat zone (2) comprises a second refractory metal oxide support material and one or more platinum group metal components supported thereon; and a washcoat overlayer (G) extending axially from the first substrate end (I) comprising a particulate metal oxide having a loading of >48.8 g/l (>0.8 g/in.sup.3), wherein a total platinum group metal loading in the first catalyst washcoat zone (1) defined in grams of platinum group metal per litre of substrate volume (g/l) is greater than a total platinum group metal loading in the second catalyst washcoat zone (2) and wherein the first catalyst washcoat zone (1) comprises one or more first alkaline earth metal components, preferably barium, supported on the first refractory metal oxide support material.

The present disclosure is directed to a system for treating an exhaust gas stream from an engine, which includes a diesel oxidation catalyst (DOC) located downstream of the engine and adapted for oxidation of hydrocarbons and carbon monoxide, an injector adapted for the addition of a reductant to the exhaust gas stream located downstream of the DOC, a catalyzed soot filter (CSF) located downstream of the injector, and a selective catalytic reduction component adapted for the oxidation of nitrogen oxides located downstream of the CSF. The CSF is adapted for oxidizing hydrocarbons and includes a selective oxidation catalyst composition on a filter with high selectivity ratio for hydrocarbon oxidation:ammonia oxidation (e.g., at least 0.6).

The invention relates to a method for producing a wall-flow filter for removing fine particulate solids from gases, and to the use thereof for cleaning exhaust gases of an internal combustion engine. The invention also relates to a correspondingly produced exhaust-gas filter having a high filtration efficiency.

A particulate filter disclosed herein includes a wall-flow structure substrate 10 and a wash coat layer 20 held inside a partition 16 of the substrate 10. The wash coat layer 20 includes an inlet layer 22 formed to have predetermined length L.sub.A and thickness T.sub.A from near an end thereof on an exhaust gas inflow side X1, and an outlet layer 24 formed to have predetermined length L.sub.B and thickness T.sub.B from near an end thereof on an exhaust gas outflow side X2. The inlet layer 22 and the outlet layer 24 partially overlap each other. In the particulate filter disclosed herein, the inlet layer 22 contains a precious metal catalyst, while the outlet layer 24 contains substantially no precious metal catalyst. The length L.sub.A of the inlet layer is 50% or more and 75% or less of a total length L of the partition 16. Thus, the particulate filter is capable of achieving both PM collection performance and pressure-drop reduction performance at high levels.

Disclosed herein is a particulate filter, in particular a catalyzed particulate filter, for use in an emission treatment system of an internal combustion engine. Provided are catalyzed particulate filters, emission treatment systems with catalyzed particulate filters, methods for manufacturing catalyzed particulate filters, and methods for controlling emissions in exhaust gas from internal combustion engines with catalyzed particulate filters.

An exhaust muffler has an exhaust inlet, an exhaust outlet, as well as a catalytic converter which, in the flow direction, is disposed between the exhaust inlet and the exhaust outlet. The catalytic converter has at least one throughflow body which includes at least one wire body. At least one first component region of the throughflow body is coated with a catalytically functioning coating. The throughflow body moreover has a second component region which in terms of volume has a smaller quantity of catalytically functioning coating than the first component region.

Systems, apparatuses, and methods include a controller for an exhaust aftertreatment system including a SCR catalyst in exhaust gas-receiving communication with an engine and at least one reductant dosing system structured to provide reductant to the exhaust gas. The controller is structured to determine a concentration of one or more of NO and NO.sub.2 at or proximate an inlet of the exhaust aftertreatment system and based on a dynamic model of the SCR catalyst, information indicative of a concentration of NOx at or proximate an outlet of the exhaust aftertreatment system, and information indicative of an amount of stored reductant in the SCR catalyst. The controller is further structured to command the at least one reductant doser to increase, decrease, or maintain an amount of reductant provided to the exhaust gas based on the determined concentration of one or more of NO and NO.sub.2 in the exhaust gas.

The present invention relates to a composition comprising platinum supported on titanium oxide, the platinum particles having an average particle diameter of 50-200 nm. The composition has a surprisingly low light-off temperature for the ammonia oxidation and a high selectivity for oxidation to N2.