A device for purifying exhaust gas may be provided to purify exhaust gas in an engine includes an exhaust line through which exhaust gas discharged from the engine passes, a diesel oxidation catalyst (DOC) that is disposed in the exhaust line to purify hydrocarbon (HC) and carbon monoxide (CO) of the exhaust gas, a urea injector that injects a urea aqueous solution into the exhaust line, and a selective catalyst reduction (SCR) that reduces nitrogen oxide of the exhaust gas passing through the DOC by use of the urea aqueous solution, in which the DOC includes an LTA zeolite catalyst.

A engine exhaust system includes a diesel oxidation catalyst (DOC) configured to receive the engine exhaust gases, a first electric heater coupled to the DOC, and a selective catalytic reduction (SCR) device in fluid communication with the DOC. The engine exhaust system further includes a second electric heater coupled to the DOC, a power switch controller in electronic communication with the first electric heater and the second electric heater, and a single power source electrically coupled to the power switch controller, the first electric heater, and the second electric heater. The power switch controller includes a switch to control a power distribution between the first electric heater and the second electric heater as a function of time.

A particulate filter for use in an exhaust aftertreatment system includes a ceramic substrate and a plurality of ceramic nanofibers associated with pores of the ceramic substrate. The plurality of ceramic nanofibers may be positioned on pores of the ceramic substrate, within pore channels of the ceramic substrate, or both on pores of the ceramic substrate and within pore channels of the ceramic substrate.

An exhaust system for a compression ignition engine comprising an oxidation catalyst for treating carbon monoxide (CO) and hydrocarbons (HCs) in exhaust gas from the compression ignition engine, wherein the oxidation catalyst comprises: a platinum group metal (PGM) component selected from the group consisting of a platinum (Pt) component, a palladium (Pd) component and a combination thereof; an alkaline earth metal component; a support material comprising a modified alumina incorporating a heteroatom component; and a substrate, wherein the platinum group metal (PGM) component, the alkaline earth metal component and the support material are disposed on the substrate.

A selective catalytic reduction filter (SCRF) including a wall-flow substrate having inlet channels and outlet channels is provided. A first selective catalytic reduction (SCR) catalyst zone is present in the inlet channels, and a second SCR catalyst zone is present in the outlet channels. The first SCR catalyst zone includes an iron-exchanged zeolite catalyst, and the second SCR catalyst zone includes a copper-exchanged zeolite catalyst. Exhaust gas treatment systems including the SCRF and methods of reducing production of nitrous oxide (N.sub.2O) during selective catalytic reduction of an exhaust gas stream using the SCRF are also provided herein.

A gasoline particulate filter for an exhaust system of a gasoline internal combustion engine includes a substrate and a catalytic coating disposed on the substrate. The catalytic coating has a carrier and at least one catalytically active ingredient. The catalytic coating has a carrier loading less than or equal to 0.5 g/in.sup.3 (0.03 g/cm.sup.3), and a catalytically active ingredient loading greater than or equal to 0.01 g/ft.sup.3 (0.35 g/m.sup.3) and less than 2 g/ft.sup.3 (70.63 g/m.sup.3).

Exhaust generated from an internal combustion engine includes particulates and gas-phase volatile hydrocarbon condensables. The exhaust is cooled in an exhaust gas cooler from a first temperature to a second temperature such that a first portion of the gas-phase volatile hydrocarbon condensables in the exhaust condense to the liquid phase and a second portion of the gas-phase volatile hydrocarbon condensables in the exhaust condense on black carbon particles to form semivolatile brown carbon particulates. Some or all of the liquid-phase volatile hydrocarbon condensables and the semivolatile brown carbon particulates are trapped in a gasoline particulate filter or a catalyzed gasoline particulate filter located downstream of the exhaust gas cooler.

The present invention relates to a SCR catalyst comprising a carrier substrate of the length L, which is a flow-through substrate, and a coating A which comprises a small pore zeolite, copper and palladium.

The present invention relates to a porous alpha-SiC-containing shaped body with a gas-permeable, open-pored pore structure comprising platelet-shaped crystallites which are connected to form an interconnected, continuous skeletal structure, wherein the skeletal structure consists of more than 80 wt.-% alpha-SiC, relative to the total weight of SiC, a process for producing same and its use as a filter component.

A filter with a frame and media is disclosed for removing chemical substances from air or other gas. The media has multiple slit and expanded sheet layers, or other air-permeable layers, with molecular catalyst material mounted on one or more of the layers. The air or other gas flowing through the media makes sufficient contact with the catalyst to chemical react substances therein with the catalyst to remove or greatly reduce the substances. This can be used to remove or reduce odors, formaldehyde or any other substance without substantial pressure drop due to the large openings in the layers. The layers may be pleated to give strength to the media.