Disclosed in certain embodiments is a sulfur tolerant catalytic system that includes a catalytic material coated onto a substrate. Certain embodiments are directed to a method of preparing a sulfur-tolerant catalyst.

An ammonia slip catalyst having an SCR catalyst and an oxidation catalyst comprising at least two metals, each of which is selected from a specific group, and a substrate upon which at least oxidation catalyst is located is described. The ammonia slip catalyst can have dual layers, with one of the layers containing an SCR catalyst, a second layer containing the oxidation catalyst with comprises at least two metals, each of which is selected from a specific group, and the ammonia slip catalyst does not contain a platinum group metal. Methods of making and using the ammonia slip catalyst to reduce ammonia slip are described.

The present invention relates to an exhaust gas treatment system for treating an exhaust gas stream leaving an internal combustion engine, wherein said exhaust gas treatment system comprises (i) a first catalyst comprising a coating and a first substrate, wherein the coating comprises a vanadium oxide supported on a first oxidic support comprising titanium; (ii) a hydrocarbon injector for injecting a fluid comprising hydrocarbons into the exhaust gas stream exiting the outlet end of the first catalyst according to (i); (iii) a second catalyst comprising a coating and a second substrate, wherein the coating comprises palladium on a second oxidic support comprising one or more of zirconium, silicon, aluminum and titanium.

The present invention relates to an ammonia oxidation catalyst for the treatment of an exhaust gas stream, the catalyst comprising a coating disposed on a substrate, wherein the coating comprises a selective catalytic reduction component being a zeolitic material comprising one or more of copper and iron; and an oxidation catalytic component comprising platinum supported on a porous non-zeolitic oxidic support, wherein the oxidation catalytic component further comprises a first oxidic material supported on the porous non-zeolitic oxidic support supporting platinum, wherein the first oxidic material comprises titania.

The present invention provides an exhaust gas purifying catalyst including a first catalyst layer (12). The first catalyst layer (12) includes a first section (14) and a second section (15) in an exhaust gas flow direction, the first section (14) being located on an upstream side in the exhaust gas flow direction relative to the second section (15). The first section (14) and the second section (15) both contain a catalytically active component including a specific element. A concentration of the specific element is higher in the first section (14) than in the second section (15). A concentration gradient of the specific element contained in the first section (14) in a thickness direction of the catalyst layer (12) is milder than a concentration gradient of the specific element contained in the second section (15) in the thickness direction.

A catalyst material for abatement of exhaust gas emissions from a lean burn engine is provided, the catalyst material including a metal-exchanged SAPO-34 material, and an oxide layer at least partially covering an outside surface of the SAPO-34 material, wherein the oxide layer is not substantially blocking the pores of the SAPO-34 material.

The disclosure is directed to an exhaust gas heating unit for an exhaust gas system of an internal combustion engine. The exhaust gas heating unit includes at least one electrically conductive heating conductor element, wherein the at least one electrically conductive heating conductor element is configured from bent flat strip material. The exhaust gas system conducts exhaust gas defining an exhaust gas primary flow direction (H). The heating conductor element can have a plurality of broad sides arranged to be substantially parallel to the exhaust gas primary flow direction (H) and a plurality of end faces arranged substantially orthogonally to the exhaust gas primary flow direction (H).

An exhaust gas purification catalyst device has catalyst coating layers, which extend from the upstream side to the downstream side of the exhaust gas flow. The catalyst coating layers each have at least three zones present in order from the upstream side to the downstream side of the exhaust gas flow, and each of these at least three zones is an oxidation catalyst zone or a reduction catalyst zone. In the uppermost layer of an oxidation catalyst zone, the total number of atoms of platinum and palladium is greater than the number of atoms of rhodium; in the upper most layer of a reduction catalyst zone, the number of atoms of rhodium is greater than the total number of atoms of platinum and palladium. The oxidation catalyst zones and the reduction catalyst zones alternate at least twice in the exhaust gas flow direction.

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 surfaces of the partition walls that each face the inflow-side cell and/or 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 from 3 to 10% based on the apparent area of the catalyst portion present on the partition wall.

The presently claimed invention provides a tri-metallic layered catalytic article comprising: a) a top layer comprising platinum supported on at least one of an oxygen storage component, zirconia component and an alumina component, and rhodium supported on an oxygen storage component; b) a bottom layer comprising a front zone and a rear zone, said front zone comprising palladium supported on an oxygen storage component and an alumina component, and the rear zone comprises platinum supported on at least one of an alumina component, a ceria component, and an oxygen storage component; and c) a substrate, wherein the weight ratio of palladium to platinum is in the range of 1.0:0.4 to 1.0:2.0.