Abstract: A method for reducing the particle and nitrogen oxide proportion in an exhaust gas flow of an internal combustion engine includes supplying a reducing agent to the exhaust gas flow, subjecting the exhaust gas flow containing the reducing agent to particle filtering, and then carrying out a selective catalytic reduction of at least a portion of the nitrogen oxides in the exhaust gas flow. The method and an exhaust gas treatment unit make it possible to simultaneously reduce the proportion of particles and nitrogen oxides in the exhaust gas. Ammonia, in particular, is used as the reducing agent. Regeneration of the particle filter is promoted by leading an ammonia-containing flow of gas through the particle filter. The method and device make it possible to consume less fuel with the same reaction rate and, at the same time to reduce available installation space, in comparison with existing corresponding prior art systems.

Abstract: A low-cost catalytic article is provided for treating gaseous fluid streams such as exhaust streams from gasoline-powered engines. The articles contain residence chambers defined by chamber walls and foraminous catalytic elements that contain a catalyst composition for converting a reactant contained in the fluid stream, and deflectors, which increase the residence time of the fluid stream in the residence chamber and the contact time of the fluid stream with the catalytic element.

Abstract: A marine engine exhaust system has an oxygen sensor located within a catalyst housing structure and downstream from a catalyst device. The oxygen sensor is located away from a reversion liquid trajectory path that defines the likely path of liquid water flowing in a reverse direction through the marine engine exhaust system toward a plurality of exhaust ports of the engine. By locating the oxygen sensor away from this reversion liquid trajectory path, the likelihood of damage to the oxygen sensor from contact with liquid water is significantly reduced.

Abstract: A layered, three-way conversion catalyst having the capability of simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides is disclosed. In one or more embodiments, the catalyst comprises three layers in conjunction with a carrier: a first layer deposited on the carrier and comprising palladium deposited on a refractory metal oxide and an oxygen storage component; a second layer deposited on the first layer and comprising rhodium deposited on a refractory metal oxide and an oxygen storage component; and a third layer deposited on the second layer and comprising palladium deposited on a refractory metal oxide.

Abstract: A thermal insulating material which can be efficiently produced while the content of organic matters, such as organic fibers and/or an organic binder, is reduced to the same or lower degree as compared with the thermal insulating material used in a conventional pollution control device (e.g., catalytic converter), and which can be applied to a pollution control element (e.g., catalytic element) while avoiding, as much as possible, an unpleasant feeling to the operator. A thermal insulating material comprising a thermal insulating material body formed of a bulk material of inorganic fibers, and a coating provided on at least one surface of said thermal insulating material body.

Abstract: An aftertreatment device (10, 110, 210) for use on an engine (16) having a cylinder head (14) includes an exhaust manifold (12, 112, 212) having an outlet (26), and a plurality of catalyst assemblies (28) located upstream of the outlet. The catalyst assemblies (28) define an exhaust gas passageway (38, 138, 238) that is in fluid communication with the engine (16) and in fluid communication with the outlet (26). A catalyst substrate (30) is disposed in the catalyst assemblies (28).

Abstract: A layered, three-way conversion catalyst having the capability of simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides is disclosed. In one or more embodiments, the catalyst comprises three layers in conjunction with a carrier: a first layer deposited on the carrier and comprising palladium deposited on a refractory metal oxide and an oxygen storage component; a second layer deposited on the first layer and comprising rhodium deposited on a refractory metal oxide and an oxygen storage component; and a third layer deposited on the second layer and comprising palladium deposited on a refractory metal oxide.

Abstract: A NOx removal catalyst comprising a carrier that includes a zeolite, and preferably a ?-zeolite, that has undergone ion exchange with iron, and ferric oxide supported on the carrier. This NOx removal catalyst can be used favorably in a selective catalytic reduction process wherein nitrogen oxides contained in the exhaust gas from a diesel engine are reduced and removed by ammonia.

Abstract: A system and method including a radially non-uniformly plugged flow-through honeycomb substrate positioned upstream of a wall-flow particulate filter for controlled thermal regeneration of the wall-flow particulate filter, the flow-through honeycomb substrate having a flow-through region including a first portion of parallel channels and a flow-control region including a second portion of parallel channels, the first portion of the parallel channels including unplugged channels and the second portion of the parallel channels including plugged channels, with the flow-control region adjusting flow distribution through the flow-through honeycomb substrate.

Abstract: The exhaust gas purification device has a first chamber having an exhaust pipe inlet, an ambient air inlet, and an exhaust gas outlet. A Venturi is arranged within the chamber, having an inlet end communicating with an ambient air inlet, a throat, and an outlet end communicating with an exhaust gas outlet. The Venturi has an exhaust gas inlet between its inlet end and its outlet end, receiving exhaust gas from within the chamber, directed generally towards the outlet end of the Venturi, so that ambient air and exhaust air are mixed in passing through the Venturi to its exhaust gas outlet. A perforated pipe within the first chamber receives the exhaust gas, and the exhaust gas escapes there from via the perforations, into the chamber and thence to the Venturi. A second chamber, having a catalytic substrate assembly mounted therein, receives the mixed ambient air and exhaust air from the exhaust gas outlet of the Venturi, and has an exhaust pipe outlet.

Abstract: A process for treating exhaust gas from a compression ignition engine wherein substantially all fuel for combustion is injected into a combustion chamber prior to the start of combustion comprises contacting the exhaust gas with a catalyst comprising a supported palladium (Pd) catalyst.

Abstract: This catalyst system simultaneously removes ammonia and enhances net NOx conversion by placing an NH3—SCR catalyst formulation downstream of a lean NOx trap. By doing so, the NH3—SCR catalyst adsorbs the ammonia from the upstream lean NOx trap generated during the rich pulses. The stored ammonia then reacts with the NOx emitted from the upstream lean NOx trap—enhancing the net NOx conversion rate significantly, while depleting the stored ammonia. By combining the lean NOx trap with the NH3—SCR catalyst, the system allows for the reduction or elimination of NH3 and NOx slip, reduction in NOx spikes and thus an improved net NOx conversion during lean and rich operation.

Abstract: A catalyst structure for treating exhaust gas from a lean burn internal combustion engine comprises a substrate monolith comprising a lean NOX catalyst (LNC) composition associated with at least one partial oxidation catalyst (POC), wherein the LNC composition is selected from the group consisting of: (a) silver or a silver compound supported on alumina; and (b) at least one metal selected from the group consisting of copper (Cu), iron (Fe), cobalt (Co) and cerium (Ce) supported on at least one zeolite, and wherein the at least one POC is selected from the group consisting of: (i) a bulk oxide, a bulk composite oxide or a bulk mixed oxide comprising at least one metal selected from the group consisting of manganese (Mn), iron (Fe), cerium (Ce) and praseodymium (Pr); and (ii) at least one of rhodium (Rh) and palladium (Pd) disposed on at least one inorganic oxide support.

Abstract: An exhaust system for a mobile combustion engine includes at least one exhaust pipe. The exhaust pipe has at least one catalytically active reaction chamber, inside which long-chain hydrocarbons contained in the exhaust gas are cracked. A method for operating such an exhaust system is also provided.

Abstract: The invention relates to an exhaust-gas heat exchanger, in particular an exhaust-gas cooler (1) for exhaust-gas recirculation (AGR) in motor vehicles equipped with channels, through which exhaust gas flows. According to the invention, a catalyst (8), in particular an oxidation catalyst, is connected upstream of the exhaust-gas heat exchanger (1).

Abstract: A multi-cylinder internal combustion engine including a plurality of banks and a turbocharger is oriented laterally within an engine compartment, wherein exhaust gas passages are connected to exhaust manifolds of each bank, a turbine of the turbocharger is installed in the exhaust gap passage of the bank positioned closest to the front side of the vehicle, and the turbocharger is disposed at a front position within the engine compartment.

Abstract: An exhaust pipe 1 having a circular cross section is connected to a circular cylindrical housing 2 which creates part of pipe conduit. The housing 2 forms a storage space 21 having a diameter larger than the diameter of the exhaust pipe 1 and connecting to the rear connection part 22. The connection part 22 is tapered toward the downstream exhaust pipe 12 and the diameter of the connection part 22 is gradually reduced and its opening is welded into the opening of the downstream exhaust pipe 12. And a cylindrical honeycomb catalyst carrier 3 is stored in the storage space 21 so that the outer surface of the catalyst carrier is in contact with the inner surface of the storage space 21. An expanded portion 23 having a diameter larger than the diameter of the storage space 21 is outwardly expanded from the outer circumference of the housing 2 and connectingly provided on the front face of the storage space 21.

Abstract: An exhaust treatment system is provided having a first exhaust passageway fluidly connected to an engine. A particulate filter and a selective catalytic reduction catalyst are situated within the first exhaust passageway. In addition, the system has a first oxidation catalyst located within the first exhaust passageway upstream of the particulate filter and the selective catalytic reduction catalyst. The system also has a second exhaust passageway fluidly connected to the first exhaust passageway upstream and downstream of the first oxidation catalyst. The exhaust treatment system further has a sensor configured to sense a parameter indicative of an exhaust gas temperature. Furthermore, the system has a controller configured to direct exhaust gas through the first oxidation catalyst when the exhaust gas temperature is below a threshold temperature and direct the exhaust gas through the second exhaust passageway when the exhaust gas temperature is above the threshold temperature.

Abstract: An exhaust gas pollution treatment device, having an inlet pipe, an outlet pipe with an exhaust path extending between the inlet pipe and the outlet pipe. A gas permeable backbone member is positioned in the exhaust path and a substantially fibrous nonwoven refractory material is disposed on the backbone.

Abstract: The present invention relates to a system that is capable of freely selecting one or two or more types of fuel and supplying the selected types of fuel to an internal combustion engine. Disclosed is a hydrogen-fueled internal combustion engine that operates upon receipt of one or more types of fuel that are selected from hydrogenated fuel and a dehydrogenated product and hydrogen, which are obtained by dehydrogenating the hydrogenated fuel. The hydrogen-fueled internal combustion engine comprises: a hydrogenated fuel storage section; reaction means for invoking a dehydrogenation reaction; separation means for separating hydrogen-rich gas and dehydrogenated product; and a dehydrogenated product storage section for storing the separated dehydrogenated product.

Abstract: An exhaust gas system for an internal combustion engine, comprising an oxidation catalytic converter disposed in a first exhaust gas manifold section with which the exhaust gas outlets of a first portion of the cylinders communicate, and a hydrolysis catalytic converter disposed in a second exhaust gas manifold section with which the exhaust gas outlets of the remaining portion of the cylinders communicate. The hydrolysis catalytic converter, together with the oxidation catalytic converter that annularly surrounds it, are installed in a common housing. A tubular portion of the second exhaust gas manifold section extends into the housing and accommodates the hydrolysis catalytic converter in its end portion. A tubular portion of a first exhaust gas manifold section surrounds the tubular portion of the second exhaust gas manifold section, resulting in an annular in-flow chamber for the oxidation catalytic converter that simultaneously serves as a heating chamber.

Abstract: An exhaust system for discharging exhaust gases through an exhaust passageway, emitted from a multi-cylinder combustion engine mounted on a motor vehicle includes a partition plate formed therein for dividing the exhaust passageway into a plurality of juxtaposed exhaust passages and having a communicating hole defined therein, and an exhaust gas sensor positioned at a location in proximity of the communicating hole for detecting a composition of the exhaust gases.

Abstract: An improved exhaust system for a diesel engine and an improved overhead exhaust manifold segment therefore wherein the improvement comprises a plurality of catalytic converter elements removably positionable in the overhead exhaust manifold over the outlet ends of a series of exhaust port legs extending upwardly to the bottom of the overhead exhaust manifold from the cylinder exhaust ports.

Abstract: To provide a muffler for a compact combustion engine, which is simple in structure and effective to sufficiently reduce the temperature of exhaust gases while avoiding contact with an external air, an exhaust guide passage 7 for communicating the exhaust gases (G) to a discharge port (63) is provided within an interior hollow of a muffler housing 6 defining an exhaust chamber (61) therein, and a side wall of this exhaust guide passage (7) is constituted by a portion (6W) of the muffler housing (6) and a duct wall (71) jointed to the muffler housing (6).

Abstract: A catalyst deterioration detecting system of an internal combustion engine includes a measuring unit that measures the oxygen storage capacity of a catalyst, a detector that detects or estimates the temperature of the catalyst, and a detector that detects poisoning of the catalyst based on the relationship between a change in the catalyst temperature and a change in the oxygen storage capacity corresponding to the change in the catalyst temperature. The change in the oxygen storage capacity corresponding to the change in the catalyst temperature varies depending on the presence or absence of poisoning of the catalyst. Thus, the catalyst deterioration detecting system is able to favorably detect poisoning of the catalyst by utilizing this relationship, and distinguish temporary deterioration due to catalyst poisoning from permanent deterioration. A method of detecting deterioration of the catalyst is also provided.

Abstract: One embodiment of a method of operating a NOx abatement system comprises: introducing an exhaust stream to an ammonia generator in a normal flow direction, adsorbing NOx from the exhaust stream in the ammonia generator, diverting the exhaust stream around the ammonia generator, introducing hydrogen to the ammonia generator in a direction opposite the normal flow direction, and generating ammonia within the ammonia generator.

Abstract: To provide an exhaust system (100) for an internal combustion engine having a housing (10) in which there are provided at least one exhaust inlet port (15b) and another exhaust discharge port (15a), and a catalyst element (22), which is disposed within the housing (10) of the exhaust system (100) for purifying the exhaust of the internal combustion engine in such a manner that a substantial part of the exhaust at least is caused to flow through the catalyst element (22), that is readily manufacturable at a low cost and still allows for purification of the entire exhaust by the catalyst element without causing power loss to the internal combustion engine, it is suggested that the exhaust gases (27) alternately flow through the catalyst element (22) through an exhaust conducting means (17).

Abstract: The invention is directed to an exhaust-gas muffler (1) of a handheld work apparatus driven by an internal combustion engine. The exhaust-gas muffler (1) includes a muffler housing (2) which includes an engine-end wall (3) having an inlet window (4) as well as an outlet (5). Attachment means (6) for fixing the exhaust-gas muffler (1) on the internal combustion engine are provided on the engine-end wall (3) in the region of the inlet window (4). The engine-end wall (3) is provided with a reinforcing sheet metal piece (7) on the inner side of the exhaust-gas muffler (1) in the region of the attachment device (6). A discharge channel (8), which leads to the outlet (5), is formed at least between a part region of the reinforcing sheet metal piece (7) and the adjoining region of the muffler housing (2).

Abstract: Various systems and methods are disclosed for carrying out combustion in a fuel-cut operation in some or all of the engine cylinders of a vehicle. Further, various subsystems are considered, such as fuel vapor purging, air-fuel ratio control, engine torque control, catalyst design, and exhaust system design.

Abstract: The invention proposes an exhaust-gas purification unit for purifying the exhaust gas from an internal combustion engine which is preferably operated in lean-burn mode, in particular a diesel engine used in motor vehicles, in which a particulate filter and a SCR catalytic converter are arranged in the exhaust pipe in succession in the direction of flow, and having a reducing-agent supply, it being possible for ammonia to be added to the exhaust gas from the internal combustion engine on the entry side of the SCR catalytic converter by the reducing-agent supply. According to the invention, the exhaust-gas purification unit includes a hydrogen-generating unit for enriching the exhaust gas from the internal combustion engine with the hydrogen which it generates. Use in motor vehicles.

Abstract: An internal combustion engine with an exhaust gas purification device is provided in which the NOx held in a NOx catalyst can be efficiently reduced and purified, and a sufficient amount of NOx can be reduced, thereby making it possible to regenerate the NOx catalyst over a wide range thereof. When processing of releasing and reducing the NOx held in the NOx catalyst 33 for purification, light oil is injected by an addition valve 37 so as to be supplied to the NOx catalyst 33 together with the exhaust gas, and after the droplet-like light oil adheres to the entire area of the NOx catalyst 33, the flow rate of the exhaust gas is decreased.

Abstract: An engine assembly may include an engine having a plurality of combustion cylinders, and an exhaust manifold configured to receive exhaust from the plurality of combustion cylinders. The exhaust manifold may be divided into first and second sections. The first section may be fluidly coupled to a first group of combustion cylinders, and the second section may be fluidly coupled to a second group of combustion cylinders. The engine assembly may also include a turbocharger having an exhaust turbine configured to receive exhaust from the first section. The engine assembly may further include a proportional valve assembly configured to selectively fluidly couple the second section to at least one of the turbocharger and an exhaust recirculation loop.

Abstract: A turbocharged engine (20, 20?, 20?, 20??) counteracts plugging of a diesel oxidation catalyst (DOC 48) by causing a first portion of exhaust from one or more exhaust manifolds (26, 28) to enter the DOC after having passed through the turbocharger (30), and causing a second portion of the exhaust (HEG) to enter the DOC without passing through the turbocharger.

Abstract: An exhaust flow director and catalyst mount for an internal combustion engine includes a collector chamber with an outlet flange adapted for direct connection with an exhaust treatment catalyst. A number of transitional guide vanes located within the collector chamber direct exhaust gases flowing from runners into the collector chamber. The runners attaching exhaust flanges and the outlet flange of the present device are substantially coplanar.

Abstract: A muffler having a muffler body divided into first and second exhaust chambers by a partitioning member which has a third exhaust chamber formed therein. An exhaust inlet introduces exhaust gas from an engine into the first exhaust chamber. First communication bores provide communication between the first and second exhaust chambers, and second communication bores provide communication between the second exhaust chamber and the third exhaust chamber. The third exhaust chamber is open to the atmosphere through an exhaust outlet pipe. An exhaust emission control catalyst is carried on an outer surface of the partitioning member facing the first and second exhaust chambers, as well as on an inner surface of the partitioning member facing the third exhaust chamber. An inner surface of the muffler body does not carry the exhaust emission control catalyst.

Abstract: A diagnostic device and method of an engine exhaust purifying system, which perform active control of an air-fuel ratio and can make diagnosis of air-fuel ratio sensors, catalysts, etc. in the engine exhaust purifying system with high accuracy and reliability while avoiding a worsening of exhaust emissions, an increase of revolution variations, etc.

Abstract: A device for purifying exhaust gases from a combustion engine (1) is provided with a first filter (10) arranged in an exhaust conduit (7) between the engine (1) and an exhaust outlet (8) for removing particular constituents from the exhaust gases, and a recirculation conduit (11) for diverting a part of the exhaust gases passing through the first filter (10) recirculating this part of the exhaust gases to the air intake (2) of the engine. A second filter (30) is arranged between the inlet end (20) of the recirculation conduit and the air intake (2) of the engine. A method for purifying exhaust gases from the combustion engine (1) and using this device to purify exhaust gas, in particular, from a diesel engine, are also provided.

Abstract: For fixing a catalytic body, which has a cylindrical case and is housed in an exhaust pipe, to the exhaust pipe that serves as part of an exhaust system connected to an engine. The catalytic body can be housed in and fixed to the exhaust pipe even if the catalytic body and the exhaust pipe are made of different materials, thus increasing the freedom in choosing materials for the case of the catalytic body and the exhaust pipe. A bracket, which is made of the same material as an exhaust pipe, is welded to an inner circumferential surface of the exhaust pipe. The bracket is crimped on the case of the catalytic body.

Abstract: A two cycle internal combustion engine cylinder having a piston chamber. The cylinder includes transfer ports; and an exhaust port divided into at least two sections. A first one of the sections has an aperture at the piston chamber with a top surface located closer to a top of the piston chamber than a top surface of an aperture of a second one of the sections at the piston chamber. The first section has a cross-sectional area which is smaller than a cross-sectional area of the second section. The aperture into the first section is located further away from the transfer ports than the aperture into the second section.

Abstract: An embodiment includes an apparatus and method of distributing gases within a catalytic converter assembly. Gases flow through at least one inlet into a housing and out of the housing through at least one outlet. A substrate is disposed at least partially between at least one of the at least one inlet and at least one of the at least one outlet. The mass flow rate of the gases across at least one surface of a deflector are substantially equalized as the gases flow through at least one of the at least one inlet into the housing and out of the housing through at least one of the at least one outlet.

Abstract: An internal combustion engine is provided in which the temperature of an exhaust gas gradually decreases from its upstream side to its downstream side, and the temperature of a working medium of a heat exchanger, which flows in the opposite direction to the exhaust gas, gradually increases from its upstream side to its downstream side. The temperature difference between the exhaust gas temperature and the working medium temperature is the smallest at the interface between a liquid phase region and a two-phase region of the working medium, and since a catalyst device is incorporated at the upstream side, relative to the flow of exhaust gas, of the vicinity of the position where the temperature difference is the smallest, it is therefore possible for the heat exchanger to utilize the heat generated by the catalyst device effectively.

Abstract: In an exhaust emission control system for an engine, comprising an exhaust emission control catalyst disposed in an exhaust muffler whose inside is divided into a plurality of chambers, at least a portion of the inside of the exhaust muffler is divided into a first chamber for converting mainly NOx in exhaust gas and a second chamber for converting HC and CO in the exhaust gas. The exhaust muffler comprises: a partition wall having a conduit for guiding the exhaust gas from the first chamber to the second chamber; an exhaust gas inlet for introducing the exhaust gas into the first chamber; an external-air suction means for sucking external air into the second chamber; and a discharge pipe for discharging the external air and the exhaust gas flowing through the second chamber.

Abstract: In an engine intake A/F ratio control system in an outboard engine system, a secondary air passage (P) for supplying secondary air for regulating the A/F ratio of an air-fuel mixture is connected to a carburetor (33) in an intake system of an engine (E), and a duty control valve (68) is connected to the secondary air passage (P). A duty control unit (92) is connected to the duty control valve (68) for controlling the duty ratio of a pulse applied to a coil (76) of the duty control valve (68), and an LAF sensor (94) is mounted to an exhaust system for detecting an A/F ratio of an exhaust gas to input a detection signal proportional to the A/F ratio of the exhaust gas to the duty control unit (92).

Abstract: An exhaust manifold of an engine exhaust apparatus includes a plurality of exhaust branches and a straight pipe section. The exhaust branches extend toward a confluence portion, from respective upstream ends to be connected with cylinders of an engine. The straight pipe section extends from the confluence portion toward a downstream end adapted to be connected to an exhaust purifying catalyst.

Abstract: A muffler assembly for an internal combustion engine of a portable handheld work apparatus such as a motor-driven chain saw, cutoff machine or the like includes an exhaust-gas muffler (1) which has a muffler housing (10). The muffler housing (10) is formed essentially from two half shells (24, 25) connected substantially fluid-tight to each other. The interior space of the muffler housing (10) includes at least two chambers (2, 3) which are partitioned from each other by a partition wall (4). A catalytic converter (5) is mounted in the partition wall (4). In the interior space of the muffler housing (10), an exhaust-gas inlet (6) opens which is connected to an exhaust-gas stub (9) of the cylinder (8) of the engine. The exhaust-gas muffler has an exhaust-gas outlet (7) which conducts exhaust gas from the interior space.

Abstract: The invention relates to a method of operating an internal combustion engine having at least one mode of operation in which combustion substantially relies on autoignition of a compression ignitable homogeneous fuel/air mixture, more specifically of a gasoline/air mixture, the temperature in the combustion chamber being controlled by exhaust gas recirculation. To increase the charge temperature in the combustion chamber in the simplest possible manner, there is provided that the residual gases be recirculated through at least one catalyst disposed in the exhaust duct in proximity to the engine.

Abstract: Carbon-containing particulates like soot included in an exhaust gas of an internal combustion engine are collected by means of a heat-resistant filter medium. The filter medium dispersedly collects hydrocarbon compounds and the carbon-containing particulates included in the exhaust gas. Even when the exhaust gas has a lower temperature than the combustible temperature of the carbon-containing particulates, such dispersed collection ensures start of a preliminary oxidation reaction of the collected hydrocarbon compounds with oxygen included in the exhaust gas. The collected hydrocarbon compounds and the collected carbon-containing particulates are then subjected to combustion with the exhaust gas having a filter inflow temperature lower than the combustible temperature of the carbon-containing particulates by utilizing the reaction heat and active species produced by the reaction. This technique thus simply but securely regulates and reduces the carbon-containing particulates included in the exhaust gas.

Abstract: The device comprises in a cylindrical case (3) of an exhaust manifold (2) of an engine, a catalyst body (12) in a centre position, and means (14, 15) for adsorbing nitrogen oxides contained in the exhaust gases of the engine in a peripheral disposition around the catalyst body (12). Preferably, the catalyst body is disposed in a pipe (8) constituting an end part of an exhaust line (8a) and the adsorbing means (14, 15) is disposed in an annular space provided between the exhaust pipe (8) surrounding the catalyst body (12) and the case (3) of the manifold (2). The device permits limiting the discharges of nitrogen oxides of the exhaust gases in all the phases of operation of the engine.

Abstract: An NOx storage-and-reduction type catalyst is used which exhibits a saturated NOx storage amount of 5 g or more as NO2 with respect to 1 liter of a catalyst volume at 500° C., and rich spiking is controlled so that an actual NOx storage amount of the NOx storage-and-reduction type catalyst becomes 50% or less of the saturated NOx storage amount. Since the saturated NOx storage amount is large, the NOx storage amount is large even when it is 50% or less, it is possible to prolong intervals of the rich spiking. Then, since NOx storage component stores NOx preferentially into the sites which are likely to store and release NOx, a reduction efficiency is high. Therefore, while prolonging the intervals of the rich spiking and sustaining an effect of mileage improvement, it is possible to improve the reduction efficiency of NOx.

Abstract: An apparatus for modifying an exhaust stream of a diesel engine is provided. The apparatus includes a muffler arrangement having an exhaust inlet and an exhaust outlet in construct and arrange for sound attenuation therein. The apparatus also includes a catalytic converter arrangement positioned within the muffler arrangement between the exhaust inlet and exhaust outlet. During operation, the exhaust flow is directed both through the muffler arrangement and the catalytic converter arrangement, to advantage.