Provided are: a hydrocarbon adsorbent capable of adsorbing hydrocarbons, storing the adsorbed hydrocarbons up to a relatively high temperature, and desorbing the adsorbed and stored hydrocarbons at a relatively high temperature; an exhaust gas purifying catalyst composition using the same; an exhaust gas purifying catalyst; and a method for treating an exhaust gas. The hydrocarbon adsorbent comprises a zeolite having an MRT-type framework structure. The hydrocarbon adsorbent comprises a small-pore zeolite having a total desorption amount ZD.sub.1 of propylene desorbed at 50° C. or higher and lower than 300° C. being 3.5 mmol/g or less and a total desorption amount ZD.sub.2 of propylene desorbed at 300° C. or higher and 500° C. or lower being 0.5 mmol/g or more, per 1 g by mass of the small-pore zeolite, when adsorbing propylene at 50° C. and then heating from 50° C. to 500° C. under the condition of 10° C./min by a temperature-programmed desorption method.

An engine system includes: an ammonia engine; a reforming device that has a reforming catalyst for cracking ammonia gas into hydrogen and configured to reform ammonia gas to generate reformed gas containing hydrogen; and a control unit. The control unit includes: a purge controller configured to control a reforming injector so as to be closed and control a reforming throttle valve so as to be opened, after an ignition switch gives an instruction of a stop of the ammonia engine; and an engine stop controller configured to control main injectors so as to be closed, after the ignition switch gives the instruction of the stop of the ammonia engine.

An aftertreatment system configured to reduce constituents of an exhaust gas produced by an engine comprises an aftertreatment component and an optical assembly. The optical assembly comprises an optical emitter configured to emit light onto a face of the aftertreatment component, and an optical detector configured to detect light reflected from the face of the aftertreatment component. A controller is configured to determine at least one of an amount of NOx gases or an amount of ammonia on the face of the aftertreatment component based on an optical parameter of the detected light that has reflected from the face of the aftertreatment component.

An aftertreatment system includes an exhaust reductant tank configured to store an exhaust reductant. A filter is fluidically coupled to the exhaust reductant tank. The aftertreatment system includes a hydrocarbon detection device configured to indicate the presence of a hydrocarbon in the exhaust reductant. A catalyst is included in the system and configured to treat the exhaust reductant flowing through the system. The hydrocarbon detection device can include a hydrophobic paper, and can be disposed in the filter.

A post-treatment system includes two SCRs, a second SCR is connected to a booster in parallel, and a three-way valve is arranged before the second SCR and the booster, such that whether an exhaust gas flows through the second SCR or the booster is controlled by means of controlling the three-way valve. In the case of a low temperature, the three-way valve is controlled to close a branch of the booster, such that the exhaust gas flows through the second SCR and a first SCR that are connected in series, thereby reducing the energy loss caused by the exhaust gas flowing through the booster, and improving the NO.sub.x conversion efficiency in the case of a low temperature. In a case of a high temperature, the three-way valve is controlled to close a by-pass line, such that the exhaust gas flows through the booster and the first SCR.

An exhaust gas after-treatment device in a driveline application, which device comprising a casing having an upper surface, a lower surface and side surfaces connecting the upper and lower surfaces to form an enclosed volume. The casing is provided with an exhaust inlet opening and an exhaust outlet opening wherein exhaust gas is supplied to and discharged from the casing through the upper surface. At least one of the exhaust inlet and outlet openings is operatively connected to its corresponding inlet or outlet pipe by a pipe connector having a first opening facing the casing and a second opening facing away from the casing. The at least one pipe connector is arranged to be rotatable about the central axis of its associated inlet or outlet opening in the casing into a predetermined angular position relative to the opening in the casing.

The present application relates to a cerium-tin-based composite oxide catalyst for catalyzing purification of a nitrogen oxide, a preparation method and an application thereof. The catalyst has the following chemical composition: a cerium-tin oxide and an M oxide, wherein the M is selected from any one of or a combination of at least two of P, Ti, Zr, V, Mn, Fe, Cu, Al, Si, Ni, Hf, Nb, Ta, Cr, Mo, W, or Re. According to the present application, a cerium-tin-based composite oxide catalyst having the characteristics such as high catalytic activity, high hydrothermal stability, excellent N.sub.2 generation selectivity, a wide operation temperature window, and adaptation to high space velocity reaction conditions is prepared by means of a non-toxic and harmless raw material and a simple method, and the present application is applicable to a device for catalyzing purification of a mobile source nitrogen oxide represented by diesel vehicle exhaust gas and a fixed source nitrogen oxide represented by flue gas from a coal-fired power plant.

The present invention relates to a method for adaption of an exhaust treatment system arranged for treating an exhaust stream produced by an engine, where the exhaust treatment system includes at least a first additive dosage device, a first selective catalytic reduction catalyst arranged downstream of the first additive dosage device, a second additive dosage device arranged downstream of the first selective catalytic reduction catalyst, and a second selective catalytic reduction catalyst arranged downstream of the second additive dosage device. The method includes initiating an adaption of the second selective catalytic reduction catalyst, and controlling, during the adaption of the second selective catalytic reduction catalyst, the first additive dosage device to inject additive in accordance with at least one injection rule being designed for the adaption.

The present invention relates to a mixing apparatus for introducing and distributing a liquid additive into a gas flow, in particular for an exhaust gas system of an internal combustion engine. The mixing apparatus comprises a gas-guiding section for guiding the gas flow and a metering-in device for introducing the additive into a metering-in region of the gas-guiding section. Furthermore, a heating device for actively heating at least one heating section of the gas-guiding section is provided. The heating section is arranged in the metering-in region and/or downstream of the metering-in region. The gas-guiding section has, in the heating section, at least one elevated portion projecting radially into the gas flow for influencing the flow of the gas flow and thus the preparation of the additive.

An exhaust pipe includes a first end, a second end, and a wall connecting the first end to the second end. The first end has a first opening, and the second end has a second opening that fluidly communicates with the first opening to define a bore. The wall includes an inner curved second and an outer curved section that includes an indentation. The indentation includes a first inwardly extending part and a second inwardly extending part. The second inwardly extending part includes a through hole having an inner opening and an outer opening. The inner opening is located between the outer opening and the second opening. A diameter of the outer opening is less than a diameter of the inner opening. A thickness of the second inwardly extending part is less than the diameter of the outer opening.