The honeycomb structure body has a dense part having a change ratio of porosity calculated by the following Expression (1) that is 1 to 5%. The honeycomb structure body also has an outside-diameter decreasing part in which the outside diameter decreases from the inflow end face to the outflow end face. The honeycomb structure body has a change ratio of average diameter calculated by the following Expression (2) that is 0.2 to 3%.

(1−P.sub.x/P.sub.y)×100,  Expression (1): in Expression (1), P.sub.x denotes the porosity (%) at the center region of the outflow end face, and Py denotes the porosity (%) of a circumferential region of the outflow end face other than the center region.

(1−D.sub.x/D.sub.y)×100,  Expression (2): in Expression (2), D.sub.x denotes the average diameter (mm) of the outflow end face, and D.sub.y denotes the average diameter (mm) of the inflow end face.

The honeycomb filter of the present invention comprises a ceramic honeycomb substrate formed from a porous body of sintered ceramic particles, and a filter layer formed on the surface of the cell walls, wherein a portion of the filter layer penetrates from the surface of the cell walls into pores formed by the ceramic particles to form inter-particle filtration bodies, these inter-particle filtration bodies are formed from a plurality of spherical ceramic particles and crosslinking bodies which bind the spherical ceramic particles to each other, and the spherical ceramic particles and the crosslinking bodies form a three-dimensional network structure.

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.

An improved SCRoF (selective catalytic reduction on filter) device for treating exhaust from an internal combustion engine. The filter has numerous entry and exit channels. Exhaust enters the entry channels and flows through side walls into the exit channels. Relative to the exhaust flow path, these side walls are coated on the downstream side with a ceria-based catalyst and on the upstream side with a Cu-zeolite catalyst. This allows the filter to optimally achieve both particulate matter oxidation and NOx reduction, respectively.

An improved SCRoF (selective catalytic reduction on filter) device for treating exhaust from an internal combustion engine. The filter has numerous entry and exit channels. Exhaust enters the entry channels and flows through side walls into the exit channels. Relative to the exhaust flow path, these side walls are coated on the downstream side with a ceria-based catalyst and on the upstream side with a Cu-zeolite catalyst. This allows the filter to optimally achieve both particulate matter oxidation and NOx reduction, respectively.

Disclosed is a honeycomb support structure comprising a honeycomb body and an outer layer or skin formed of a cement that includes an inorganic filler material having a first coefficient of thermal expansion from 25° C. to 600° C. and a crystalline inorganic fibrous material having a second coefficient of thermal expansion from 25° C. to 600° C.

The honeycomb structure includes a honeycomb structure body and a pair of electrode members disposed on a side surface of the honeycomb structure body, each of the pair of electrode members is shaped in the form of a band extending in a cell extending direction, and in a cross section perpendicular to the extending direction of cells, one electrode member is disposed on a side opposite to the other electrode member via a center of the honeycomb structure body, one or more slits opened in the side surface are formed in the honeycomb structure body, the honeycomb structure body has a charging material charged into the at least one slit, the charging material contains aggregates and a neck material, and a ratio (α2/α1) of a thermal expansion coefficient α2 of the charging material to a thermal expansion coefficient α1 of the honeycomb structure body is from 0.6 to 1.5.

A candle filter comprised of a hollow cylindrical tube having a wall with an interior surface and an exterior surface, wherein the candle filter comprises high temperature resistant inorganic fibers, at least one binder, and optionally a secondary binder, wherein the at least one binder and optional secondary binder is substantially uniformly distributed across the thickness of the candle filter wall. Also, a method for making the candle filter having at least one binder, and optionally a secondary binder at least substantially uniformly distributed across the thickness of the candle filter wall.

There is provided an exhaust-gas aftertreatment arrangement for an internal combustion engine comprising a first catalytic converter, a second catalytic converter arranged in parallel with the first catalytic converter, the first and second catalytic converters being arranged to receive exhaust gas from an engine, a connection pipe fluidly connecting an outlet of the second catalytic converter with an inlet of the first catalytic converter, thereby allowing a flow of exhaust gas through the connection pipe, and an outlet valve arranged in the outlet of the second catalytic converter and downstream of the location of the connection pipe, wherein the outlet valve is configured to control a flow of exhaust gas through the second catalytic converter. There is also provided a method for controlling an exhaust-gas aftertreatment arrangement.

There is provided an exhaust-gas aftertreatment arrangement for an internal combustion engine comprising a first catalytic converter, a second catalytic converter arranged in parallel with the first catalytic converter, the first and second catalytic converters being arranged to receive exhaust gas from an engine, a connection pipe fluidly connecting an outlet of the second catalytic converter with an inlet of the first catalytic converter, thereby allowing a flow of exhaust gas through the connection pipe, and an outlet valve arranged in the outlet of the second catalytic converter and downstream of the location of the connection pipe, wherein the outlet valve is configured to control a flow of exhaust gas through the second catalytic converter. There is also provided a method for controlling an exhaust-gas aftertreatment arrangement.