A honeycomb filter includes a plugged honeycomb structure body which has cell rows arranged along one direction, in a cross section of the honeycomb structure body and including a first cell row constituted of at least one of an inflow cell and an outflow cell, and a through-cell, and a second cell row including no through-cells. A width P1 (mm) of the first cell row, a width P2 (mm) of the second cell row and a curvature radius R (m) of a curved shape of corner portions of a polygonal shape of each cell satisfy a relation of Equation (1) below: Equation (1): 0.4 (R/1000)/((P1+P2)/2) 100 20.

An apparatus for aftertreatment of exhaust gas including a housing having a longitudinal axis that extends between a first end and a second end of the housing; an exhaust inlet being positioned at a portion of the first end of the housing for entering exhaust gas flow into the interior of the housing; a first substrate being positioned within the interior of the housing downstream to the exhaust inlet, wherein the exhaust gas flow being configured to flow through the first substrate in direction of the longitudinal axis; mixer arrangement being positioned within the interior of the housing downstream to the first substrate and including: first flow guide arrangement configured to guide the exhaust gas flow to rotating and advancing gas flow in direction of a crosswise axis perpendicular to the longitudinal axis; a reactant inlet for dispensing reactant to the rotating and advancing gas flow, the reactant configured to mix with the exhaust gas; and second flow guide arrangement configured to guide the rotating and advancing mixed gas flow in direction of the longitudinal axis as a mixed exhaust gas flow; and a second substrate being positioned within the interior of the housing downstream to the mixer arrangement, wherein the mixed exhaust gas flow being configured to flow through the second substrate in direction of the longitudinal axis.

A honeycomb filter includes a plugged honeycomb structure body which has cell rows arranged along one direction in a cross section of the honeycomb structure body and including a first cell row constituted of at least one of an inflow cell and an outflow cell, and a through-cell, and a second cell row including no through-cells. A width P1 (mm) of the first cell row, a width P2 (mm) of the second cell and a curvature radius R of a curved shape of corner portions of a polygonal shape of each cell satisfy relations of Equations (1) and (2) below: Equation (1): 2100(P1/P2100)50, and Equation (2): 0.4(R/1000)/((P1+P2)/2)10020.

Coated gasoline particulate filters (cGPFs) that are produced according to varied material compositions and catalyst configurations are disclosed. The cGPFs include FeCe (rich)-activated Rh compositions that provide greater catalytic functionality. These cGPFs are incorporated within engine systems as components of TWC systems for controlling and reducing engine exhaust emissions. The conversion performance of these TWC systems is assessed and compared employing worldwide harmonized light duty test cycle (WLTC) protocol within a gasoline fueled internal combustion engine. These TWC systems exhibit a significant catalytic performance when compared with the catalytic performance of a PGM-based Original Equipment Manufacturer (OEM) catalyst employed in TWC applications. Further, TWC catalysts are produced including Fe-activated Rh layers comprising dopant elements. The catalytic performance of the TWC catalysts is evaluated by performing light-off and standard isothermal oxygen storage capacity oscillating tests. The TWC catalysts exhibit improved catalytic performance and significant oxygen storage capacity.

Catalysts comprising metal-loaded non-zeolitic molecular sieves having the CHA crystal structure, including Cu-SAPO-34, and methods for treating exhaust gas incorporating such catalysts are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stability at high reaction temperatures.

A catalyst 20 provided for a filter body for combusting PM contains activated aluminas 21 and 22, active-oxygen-release materials 23 and 24, catalytic metal 25, and alkali earth metal 26. The alkali earth metal 26 is loaded on each of the activated aluminas 21 and 22, and the active-oxygen-release materials 23 and 24. A percentage by mass of the alkali earth metal 26, loaded on the active-oxygen-release materials 23 and 24, to the active-oxygen-release material is smaller than a percentage by mass of the alkali earth metal 26, loaded on the activated aluminas 21 and 22, to the activated alumina.

The exhaust gas purification device includes: a substrate of wall flow structure having inlet cells, outlet cells and a porous partition wall; and a catalyst layer provided in at least part of internal pores of the partition wall and held on the surface of the internal pores. The relationship between an average filling factor A of the catalyst layer held in pores having a pore diameter of 5 m to less than 10 m, an average filling factor B of the catalyst layer held in pores having a pore diameter of 10 m to less than 20 m and an average filling factor C of the catalyst layer held in pores having a pore diameter of 20 m to less than 30 m, among the internal pores of the partition wall 16 in which the catalyst layer is held, satisfies the following expression: A<B<C.

A circumferential coating material to be applied to a circumferential surface of a honeycomb structure made of ceramics formed by extrusion, the circumferential coating material including a ceramic raw material that forms a circumferential coating layer, wherein the ceramic raw material contains: a ceramic mixture of first ceramic particles having particulate shapes, and second ceramic particles having particulate shapes and an average particle diameter different from an average particle diameter of the first ceramic particles; and a fiber material having an elongated strip-like shape, wherein the ceramic mixture has particle size distribution including at least two local maximum values, and the fiber material has an average fiber length ranging from 30 to 100 m in a longitudinal direction.

A catalyst-containing ceramic dust filter for off-gas or exhaust gas cleaning is prepared by a method comprising the steps of making a water-based impregnation slurry, which comprises a catalytically effective amount of at least one catalytically active metal and an oxide support, to form a catalytically active metal oxide support, impregnating the filter substrate with the impregnation slurry, spraying from the inside to control the amount of liquor while leaving the outer few millimeters of the filter wall dry, and drying the impregnated filter. The impregnated filter is preferably dried by using microwave energy.

A diesel particulate filter coated with selective catalytic reduction includes: a support in which channels are formed from a front side to a rear side, a perovskite catalyst, and a selective catalytic reduction. In particular, the channels include an inlet channel which has an opened inlet and a closed outlet, and an outlet channel which is disposed adjacent to the inlet channel and has a closed inlet and an opened outlet. The perovskite catalyst is provided in an inner surface of the inlet channel, and the selective catalytic reduction is provided in an inner surface of the outlet channel. The perovskite catalyst is represented as La.sub.1-xAg.sub.xMnO.sub.3 (here, 0<X<1).