An exhaust system for treating an exhaust gas from an internal combustion engine is disclosed. The system comprises a modified lean NO.sub.x trap (LNT), a urea injection system, and an ammonia-selective catalytic reduction catalyst. The modified LNT comprises a first layer and a second layer. The first layer comprises a NO.sub.x adsorbent component and one or more platinum group metals. The second layer comprises a diesel oxidation catalyst zone and an NO oxidation zone. The diesel oxidation catalyst zone comprises a platinum group metal, a zeolite, and optionally an alkaline earth metal. The NO oxidation zone comprises a platinum group metal and a carrier. The modified LNT stores NO.sub.x at temperatures below about 200° C. and releases at temperatures above about 200° C. The modified LNT and a method of using the modified LNT are also disclosed.

The present invention relates to a selective catalytic reduction catalyst for the treatment of an exhaust gas of a combustion engine, the catalyst comprising a substrate comprising an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end and a plurality of passages defined by internal walls of the substrate extending therethrough; a coating disposed on the substrate (i), the coating comprising a first non-zeolitic oxidic material comprising aluminum, an 8-membered ring pore zeolitic material comprising one or more of copper and iron, and a second non-zeolitic oxidic material comprising cerium and one or more of zirconium, aluminum, silicon, lanthanum, niobium, iron, manganese, titanium, tungsten, copper, molybdenum, neodymium, cobalt, chromium, tin and praseodymium; wherein at least 65 weight-% of the coating consist of the 8-membered ring pore zeolitic material comprising one or more of copper and iron.

The instant invention is based on techniques for using non-thermal plasma reactors in both the main exhaust pipe and in the exhaust gas recirculation feed pipe to reduce particulate matter sufficiently to meet EPA limits for PM and enhanced exhaust gas recirculation to meet NOx limits. More specifically, it is based upon the use of a non-thermal plasma device in which a high voltage charge in the plasma reactor causes extremely rapid oxidation of soot particles in the exhaust stream of an engine and further chemical reactions that aid in the reduction of NOx. The primary benefit of this technology is that it can be calibrated to optimize both soot and NOx reduction.

A device and a method for reducing carbon monoxide, hydrocarbons, nitrogen oxides and soot particles present in the exhaust gases of diesel engines are provided. The device includes 1) a diesel oxidation catalyst for the oxidation of carbon monoxide, hydrocarbons and nitrogen monoxide; 2) a first unit by means of which ammonia and/or a compound that breaks down to form ammonia can be metered into the exhaust gas that is to be purified; 3) a catalytically activated particulate filter, containing a wall-flow filter substrate comprising a catalytically active material that promotes the selective catalytic reduction of nitrogen oxides to form nitrogen; 4) a second unit by means of which ammonia and/or a compound that breaks down to form ammonia can be metered into the exhaust gas that is to be purified; as well as 5) a catalyst for the selective catalytic reduction of nitrogen oxides to form nitrogen.

A porous ceramic structure with low pressure loss and high catalytic performance is provided. The porous ceramic structure includes a porous structure body (i.e., honeycomb structure) composed primarily of cordierite, and manganese (Mn) and tungsten (W) that are fixedly attached to the honeycomb structure. Thus, pressure loss in the porous ceramic structure can be reduced, and an NO combustion temperature in the porous ceramic structure can be lowered. In other words, the aforementioned structure of the porous ceramic structure allows the porous ceramic structure to have low pressure loss and high catalytic performance.

Synergized platinum group metals (SPGM) with ultra-low PGM loadings employed as close-coupled (CC) three-way catalysts (TWC) systems with varied material compositions and configurations are disclosed. SPGM CC catalysts in which ZPGM compositions of binary or ternary spinel structures supported onto support oxides are coupled with commercialized PGM UF catalysts and tested under Federal Test Procedure FTP-75 within TGDI and PI engines. The performance of the TWC systems including SPGM CC (with ultra-low PGM loadings) catalyst and commercialized PGM UF catalyst is compared to the performance of commercialized PGM CC and PGM UF catalysts. The disclosed TWC systems indicate that SPGM CC TWC catalytic performance is comparable or even exceeds high PGM-based conventional TWC catalysts, with reduced tailpipe emissions.

Synergized platinum group metals (SPGM) with ultra-low PGM loadings employed as underfloor (UF) three-way catalyst (TWC) systems with varied material compositions and configurations are disclosed. SPGM UF catalysts in which ZPGM compositions of binary and ternary spinel structures supported onto support oxides are coupled with commercialized PGM close-coupled (CC) catalysts and tested under Federal Test Procedure FTP-75 within TGDI and PI engines. The performance of the TWC systems including commercialized PGM CC and SPGM UF (with ultra-low PGM loadings) catalysts is compared to the performance of commercialized PGM CC and PGM UF catalysts. The disclosed TWC systems indicate that SPGM UF TWC catalytic performance is comparable or even exceeds high PGM-based conventional TWC catalysts, with reduced tailpipe emissions.

A lean gasoline exhaust treatment catalyst article is provided, the article comprising a catalytic material applied on a substrate, wherein the catalytic material comprises a first composition and a second composition, wherein the first and second compositions are present in a layered or zoned configuration, the first composition comprising palladium impregnated onto a porous refractory metal oxide material and rhodium impregnated onto a porous refractory metal oxide material; and the second composition comprising platinum impregnated onto a porous refractory metal oxide material. Methods of making and using such catalyst articles and the associated compositions and systems employing such catalyst articles are also described.

An aftertreatment system (100) connected downstream an internal combustion engine arrangement (102) for receiving combustion gas exhausted from the internal combustion engine arrangement (102) during operation thereof, the aftertreatment system (100) comprising a primary aftertreatment system (104) comprising a first catalytic reduction arrangement (106); a secondary reduction system (108) comprising a second catalytic reduction arrangement (110).

An exhaust system for an internal combustion engine, the exhaust system comprising, a lean NO.sub.x trap, and a wall flow monolithic substrate having a pre-coated porosity of 40% or greater, and comprising an oxidation catalytic zone, the oxidation catalytic zone comprising a platinum group metal loaded on a first support, the first support comprising at least one inorganic oxide and a zinc compound.