An electric heating device for an exhaust gas catalyst, the electric heating device including a sleeve and a heating cellular structure which is heated by a flow of electric current and which is contained in the sleeve. The electric heating device being designed to be positioned in a segment of an exhaust gas pipe upstream of a catalyst, so as to completely occupy a cross section of the segment such that exhaust gases flowing in the pipe pass through the cellular matrix before reaching the catalyst. The heating cellular structure is designed to dissipate an inhomogeneous thermal power in a section perpendicular to the direction of flow of the exhaust gases, such that the temperature of the exhaust gases at the outlet of the heating cellular structure is homogeneous in a section perpendicular to the direction of flow of the exhaust gases.

A method that determines a cause for the impaired performance of a catalytic configuration of the exhaust gas of a combustion engine (231), the method including determining (s410) a course of a NOx-conversion ratio; determining (s420) a prevailing temperature of the catalytic configuration; increasing (s430) the temperature of the catalytic configuration from a prevailing temperature below a predetermined temperature value (Te) to a temperature (TSred) above the predetermined temperature value above which sulphur is removed from the catalytic configuration; and/or decreasing (s440) the temperature of the catalytic configuration from a prevailing temperature (TSred) above the predetermined temperature value (Te) to a temperature below the predetermined temperature value so as to impair the performance of the catalytic configuration in case sulphur is present; and determining (s450) one cause out of a set of causes on the basis of the course of the NOx-conversion ratio thus determined.

A system, apparatus, and method are provided for preventing the accumulation of particulate matter such as combustion soot on sensors positioned in exhaust gas conduits of internal combustion engines. In an embodiment, the apparatus includes a device for deflecting soot deposits from sensor surfaces. In an embodiment, the apparatus includes a device employing a surface acoustic wave generator for dislodging soot accumulation or measuring soot accumulations to trigger burn-off events. In an embodiment, an injector injects pressurized bursts of gas toward a sensor surface to dislodge particulate matter. In an embodiment, charged electrodes attract charged particles of soot from the exhaust gas flow to form deposits that are then subject to burn-off events.

A selective catalytic reduction catalyst for the treatment of an exhaust gas stream of a passive ignition engine, the catalyst comprising a porous wall-flow filter substrate comprising an inlet end, an outlet end, a substrate axial length (w) extending between the inlet end and the outlet end, and a plurality of passages defined by porous internal walls of the porous wall flow filter substrate; wherein the catalyst further comprises a first coating, said first coating extending over x % of the substrate axial length from the inlet end toward the outlet end of the substrate, x being in the range of from 10 to 100, wherein the first coating comprises copper and an 8-membered ring pore zeolitic material; wherein the catalyst further comprises a second coating, the second coating extending over y % of the substrate axial length from the outlet end toward the inlet end of the substrate, y being in the range of from 20 to 90, wherein the second coating comprises copper, and optionally an 8-membered ring pore zeolitic material; wherein the catalyst optionally further comprises a third coating; wherein x+y is at least 90; wherein y % of w from the outlet end toward the inlet end of the substrate define the outlet zone of the coated substrate and (100−y) % of w from the inlet end toward the outlet end of the substrate define the inlet zone of the coated substrate; wherein the ratio of the loading of copper in the inlet zone, Cu(in), calculated as CuO, relative to the loading of copper in the outlet zone, Cu(out), calculated as CuO, Cu(in):Cu(out), is less than 1:1.

A pillar shaped honeycomb structure for induction heating, the honeycomb structure being made of ceramics and including: an outer peripheral wall; and a partition wall disposed on an inner side of the outer peripheral wall, the partition wall defining a plurality of cells, each of the cells penetrating from one end face to other end face to form a flow path, wherein a composite material containing a conductor and a non-conductor is provided in the cells in a region of 50% or less of the total length of the honeycomb structure from one end face, and wherein the conductor is a conductor that generates heat in response to a change in a magnetic field.

An exhaust gas treatment assembly unit for an exhaust system of an internal combustion engine includes a tubular outer housing (12) elongated in a direction of an outer housing longitudinal axis (L.sub.A), a tubular inner housing (14) elongated in the direction of an inner housing longitudinal axis (L.sub.I), an exhaust gas treatment unit (16) being carried in the inner housing (14), and a locking fixing device (24) detachably fixing the inner housing in the outer housing. The locking fixing device (24) includes a locking fixing element (26) held at the inner housing (14) in both axial directions with a radially outwards prestressed locking meshing area (28). In association with the locking meshing area (28), a locking receiving area (42) at the outer housing (12), interacts with the locking meshing area (28) for holding the inner housing (14) in the outer housing (12) in at least one axial direction.

The present invention relates to a catalyst comprising a carrier substrate of length L and at least two washcoat layers A and B wherein washcoat layer A comprises alumina; ceria; an alkaline earth compound and/or an alkali compound; platinum, palladium or platinum and palladium; washcoat layer B comprises a zeolite and palladium, wherein the palladium is present as palladium cation in the zeolite structure or is wholly or partially present as palladium metal and/or as palladium oxide in the zeolite structure and/or on the surface of the zeolite structure; and
wherein washcoat layer A is arranged below washcoat layer B.

Disclosed is a method for diagnosing a first exhaust treatment component for treatment of an exhaust gas stream comprising means for oxidizing nitric oxide into nitrogen dioxide. A first reduction catalytic converter is arranged upstream said means for oxidizing nitric oxide into nitrogen dioxide, and a second reduction catalytic converter is arranged downstream said means. A reagent is for reduction of nitrogen oxides in said first catalytic converter, and a first sensor measures an occurrence of nitrogen oxide downstream said means but upstream said second reduction catalytic converter. The method comprises: causing a supply of reagent upstream said first reduction catalytic converter to an extent exceeding the extent to which reagent is consumed by the first reduction catalytic converter, determining a first measure of the occurrence of reagent downstream said means for oxidizing, and diagnosing said means for oxidizing nitric oxide into nitrogen dioxide based on said first measure.

The exhaust gas purification catalyst device includes an upper layer which includes first carrier particles and rhodium, and a lower layer which includes second carrier particles, and the upper layer includes a rhodium enriched area in the range a, from the upstream end in the exhaust gas flow to 50% of the upper layer length, and a range b from the upper layer top surface to 18 μm in the depth direction. The rhodium enriched area contains at least 50% and less than 100% of all the rhodium in the upper layer.

An apparatus for attachment to a tailpipe of a vehicle is disclosed herein. The apparatus includes a filter body, a honeycomb monolith, a locking collar and a removable front cover. The honeycomb monolith is composed of an adsorbent material or an absorbent material. Exhaust from the tailpipe of the vehicle is absorbed by the honeycomb monolith structure.