Described are catalytic articles comprising a substrate having a washcoat on the substrate, the washcoat containing a catalytic component having a first average (D50) particle size and a functional binder component having a second average (D50) particle size in the range of about 10 nm to about 1000 nm, wherein the ratio of the first average (D50) particle size to the second average (D50) particle size is greater than about 10:1. The catalytic articles are useful in methods and systems to purify exhaust gas streams from an engine.

An aftertreatment system comprises a first SCR system, a second SCR system positioned downstream of the SCR system and a reductant storage tank. At least one reductant insertion assembly is fluidly coupled to the reductant storage tank. The at least one reductant insertion assembly is also fluidly coupled to the first SCR system and the SCR system. A controller is communicatively coupled to the reductant insertion assembly. The controller is configured to instruct the reductant insertion assembly to asynchronously insert the reductant into the first SCR system and the second SCR system.

A filtration assembly for removing particulate matter from exhaust gas produced by an engine, including: a first filter; a second filter positioned downstream of the first filter; and a valve including: a first ring defining a plurality of first openings, and a second ring defining a plurality of second openings, the second ring abutting the first ring. The valve is moveable between a closed position in which the plurality of first openings are misaligned with the plurality of second openings to prevent a fluid from flowing through the plurality of first and second openings, and an open position in which the second ring is rotated relative to the first ring such that the plurality of first openings are aligned with the plurality of second openings allowing the fluid to flow therethrough. A first end of the valve is positioned at an outlet of the first filter, and a second end of the valve is positioned at an inlet of the second filter. In the closed position of the valve, substantially all of the exhaust gas flows through the second filter, and in the open position of the valve, at least a portion of the exhaust gas flows through the valve and bypasses the second filter.

A method of converting nitrogen oxides in a gas to nitrogen by contacting the nitrogen oxides with a nitrogenous reducing agent in the presence of a zeolite catalyst containing at least one transition metal, wherein the zeolite is a small pore zeolite containing a maximum ring size of eight tetrahedral atoms, wherein the at least one transition metal is selected from the group consisting of Cr, Mn, Fe, Co, Ce, Ni, Cu, Zn, Ga, Mo, Ru, Rh, Pd, Ag, In, Sn, Re, Jr and Pt.

An axial extension part is proposed which makes it possible to use a filter cartridge (25) of larger axial dimensions than a standard filter cartridge for which the axial depth of a hollow housing (11) of a casing (10) of a selective catalytic reduction (SCR) device has been provided. This makes it possible to have different filtration characteristics without having to modify the casing. The larger filter cartridge (25) can be inserted into the extension part when this part is mounted in the housing (11) of the casing (10). The cartridge is sealed therein when the sealing cap (21) is put in place to close the opening at the rear end of the part.

A controller for controlling regeneration of a selective catalytic reduction (SCR) catalyst of an aftertreatment system is configured to cause increase in a SCR catalyst temperature of the SCR catalyst to a first regeneration temperature, the first regeneration temperature being lower than a high regeneration temperature that is equal to or greater than 500 degrees Celsius. The controller is configured to determine an amount of ammonia slip downstream of the SCR catalyst; and cause an increase in the SCR catalyst temperature to a second regeneration temperature greater than the first regeneration temperature but lower than the high regeneration temperature based on the determined amount of ammonia slip.

An injector is provided to inject an aqueous urea solution into an exhaust line. The injector comprises a single fluid inlet, an injection passage, fluidly connecting the inlet to the injection port, and a shut-off device for the injection port. The shut-off device further comprises an actuator that is configured to selectively move a shutter between open and closed positions. A cooling passage is fluidly connected to the injection passage and is configured to cool the actuator. A fluid pressure regulator is interposed in the cooling passage.

A segmented, heated urea mixer and an exhaust system to control NOx emission from combustion engines comprising a plurality of elements, at least one mixing element independently heatable by an external power source to a temperature above a temperature of another element. A method of using the exhaust gas mixer and an exhaust gas mixer system further comprising a controller is also disclosed.

This exhaust gas purifying catalyst is provided with a substrate and a catalyst layer formed on a surface of the substrate. The catalyst layer contains zeolite particles that support a metal, and a rare earth element-containing compound that contains a rare earth element. The rare earth element-containing compound is added in such an amount that the molar ratio of the rare earth element relative to Si contained in the zeolite is 0.001 to 0.014 in terms of oxides.

An exhaust gas sample collector includes a tubular body, a plurality of inlet openings circumferentially spaced about an outer periphery of the tubular body, the plurality of inlet openings configured to receive exhaust gas, an outlet in fluid communication with the plurality of inlet openings, and a sensor configured to measure a characteristic of the exhaust gas at the outlet.