A filter includes a filter body containing a paper sheet having a surface roughness of 1.0 m or more and 10.0 m or less, and a photocatalyst particle held on the filter body and having a surface to which a metal compound having a metal atom and a hydrocarbon group is bonded via an oxygen atom. The photocatalyst particle is formed of a titanium compound particle having absorption at wavelengths of 450 nm and 750 nm in a visible absorption spectrum.

A catalyst includes LTA zeolite including copper ions, wherein a Si/Al ratio of the LTA zeolite is 2 to 50. The catalyst is coated on a honeycomb carrier or a filter. The catalyst removes NOx from a reaction gas at 100 C. or above. The catalyst has an NOx conversion rate of 80% at 450 C. or above.

Catalyst articles having a first zone containing a first SCR catalyst and a second zone containing an ammonia slip catalyst (ASC), where the ammonia slip catalyst contains a second SCR catalyst and an oxidation catalyst, and the ASC has DOC functionality, where the first zone is located on the inlet side of the substrate and the second zone is located in the outlet side of the substrate are disclosed. The catalytic articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases, in reducing the amount of ammonia slip and in oxidizing organic residues. Exhaust systems containing the catalyst articles and methods of using the catalytic articles in an SCR process, where the amount of ammonia slip is reduced and hydrocarbon are oxidized by the ASC catalyst, are also described.

An active field polarized filter includes a scrimless filter media that includes a mixture of polypropylene fibers with polymethaphenylene isophtalamide fibers. This mixture may be in the form of a nonwoven material having a weight ratio of polymethaphenylene isophtalamide fibers to polypropylene fibers ranging between 5:95 and 50:50, and even more preferably between 10:90 and 30:70.

An oxidation catalyst is described for treating an exhaust gas produced by a diesel engine comprising a catalytic region and a substrate, wherein the catalytic region comprises a catalytic material comprising: a copper (Cu) component; a platinum group metal (PGM) selected from the group consisting of (i) platinum (Pt), (ii) palladium (Pd) and (iii) platinum (Pt) and palladium (Pd); and a support material, which is a refractory oxide comprising alumina; wherein the platinum group metal (PGM) and the copper (Cu) component is each supported on the support material.

This oxidation catalyst for diesel engines is divided into an upstream-side catalyst layer and a downstream-side inner catalyst layer in the flow direction of the exhaust gas, and a downstream-side outer catalyst layer is additionally formed so as to cover the surface of the downstream-side inner catalyst layer. The upstream-side catalyst layer and the downstream-side inner catalyst layer contain Pd, and the downstream-side outer catalyst layer contains Pt. The amounts of Pt and Pd contained in the upstream-side catalyst layer and the amounts of Pt and Pd contained in the downstream-side inner catalyst layer are constantly set to certain values, while the amount of Pt contained in the downstream-side outer catalyst layer is set to a value which enables the oxidation efficiency to be at a predetermined value or higher.

A honeycomb structure includes: a honeycomb structure body; and a convex part that protrudes outward from a part of circumference of the honeycomb structure body. The convex part surrounds the circumference of the honeycomb structure body like a ring. The convex part is of a tapered shape at least at one end having a tapered face. The convex part has a circumference coating layer making up the tapered face. The convex part has a maximum thickness of 1 to 20 mm, and a rough-face region on the tapered face, the rough-face region having surface roughness of 5 to 70 m. The rough-face region has a total of a rough-face region angle of 108 or more. An inclination angle formed between the tapered face and the extending direction of the cells is 10 to 80 degrees.

An exhaust treatment device is disclosed. The exhaust treatment device has a compact configuration that includes integrated reactant dosing, reactant mixing and contaminant removal/treatment. The mixing can be achieved at least in part by a swirl structure and contaminant removal can include NO.sub.x reduction.

A catalyst includes LTA zeolite including copper ions, wherein a Si/Al ratio of the LTA zeolite is 2 to 50. The catalyst is coated on a honeycomb carrier or a filter. The catalyst removes NOx from a reaction gas at 100 C. or above. The catalyst has an NOx conversion rate of 80% at 450 C. or above.

The catalytic converter of the vehicle includes: an LNT converter including an LNT catalyst to reduce nitrogen oxides; an SDPF converter including an SDPF catalyst to capture particulate matters and reduce the nitrogen oxides; a connection housing connecting the LNT converter and the SDPF converter to each other; an injection module provided in the connection housing to inject the reducing agent from the LNT converter toward the SDPF converter; an impactor atomizing and vaporizing the reducing agent injected from the injection module; a first guide mixer provided inside the connection housing to form a swirl-direction flow of the exhaust gas mixed with the reducing agent atomized through the impactor; and a second guide mixer provided downstream of the first guide mixer inside the connection housing to form an additional swirl-direction flow of the exhaust gas mixed with the reducing agent.