The invention concerns a circuit intended to transfer, by means of a pump, first fluid, such as an aqueous urea solution, from a reservoir to an injector, said circuit also containing a second fluid, such as air, and said circuit comprising, downstream of the pump and of the reservoir, a downstream circuit portion which includes, on the one hand, a main branch which leads to the injector and, on the other hand, bypass branch which returns to the reservoir and which is provided with a double-seat valve designed to selectively and automatically adopt: purge configuration allowing to purge the second fluid through the valve out of the main branch, a pressurized supply configuration allowing to direct the first fluid to the injector under a predetermined working pressure, and a recirculation configuration allowing a recirculation through the bypass branch, and to the reservoir, of the first fluid coming from said reservoir.

An exhaust system includes a selective catalytic reduction (SCR) catalyst, a diesel oxidation catalyst, and an ammonia slip catalyst. The SCR catalyst is configured to reduce nitrogen oxide in exhaust gas produced by a diesel engine. The diesel oxidation catalyst is configured to reduce particulate matter, hydrocarbon, and carbon monoxide in the exhaust gas. The diesel oxidation catalyst is disposed downstream of the first SCR catalyst. The ammonia slip catalyst is configured to reduce ammonia in the exhaust gas. The ammonia slip catalyst is disposed downstream of the first SCR catalyst and upstream of the first diesel oxidation catalyst.

A provision of assemblies and methods for treating exhaust gases from combustion devices to reduce air contaminants in the exhaust gas. The exhaust from a combustion device is cooled, followed by passing the exhaust through first and second catalytic chambers with an oxygen enrichment means in between the catalytic chambers. The catalytic chambers comprise at least one catalyst that substantially reduces nitrogen oxides or carbon monoxide or both.

A reaction device of a marine SCR system comprises a conveying unit (110), a reaction chamber (120), at least one catalyst module (130), and an air homogenization chamber (140), wherein, the conveying unit (110) includes an input pipeline (111) and an output pipeline (112) sleeved outside the input pipeline (111). One end of the reaction chamber (120) is connected to the conveying unit (110). The reaction chamber (120) comprises an inner cylinder (121) and an outer cylinder (122) sleeved outside the inner cylinder (121), the inner cylinder (121) is in communication with the input pipeline (111), and the outer cylinder (122) is in communication with the output pipeline (112). The catalyst module (130) is provided between the inner cylinder (121) and the outer cylinder (122). The air homogenization chamber (140) is connected to the other end of the reaction chamber (120) and is in communication with both the inner cylinder (121) and the outer cylinder (122). With the reaction device of the marine SCR system whereby the outer cylinder is sleeved outside the inner cylinder, flue gas from the inner cylinder is turned by the air homogenization chamber and then flows back into the outer cylinder. This can not only substantially reduce the size of the reaction device to improve the integration of the SCR system, but also allow the flue gas to turn in the air homogenization chamber and then flow back, so that the flue gas and a reducing agent can be fully mixed in the air homogenization chamber to improve the catalytic reaction efficiency.

Provided are an LNT layered catalyst for a lean burn gasoline engine having an enhanced NOx storage rate and capable of developing a higher NOx purification rate, and an exhaust gas purification apparatus using the same, the LNT layered catalyst including a substrate, a first catalyst layer including ceria-alumina particles carrying Pt, Pd, and BaO, and a second catalyst layer including ceria-alumina particles carrying Pt and Rh, in which a content of Pt in the first catalyst layer is 0.45 to 0.85 mass %; among Pt included in the first catalyst layer, a content proportion in a first depth region is 88 to 90 mass %, and a content proportion in a second depth region is 10 to 12 mass %; a content of Ba in the first catalyst layer is 4 to 11 mass %; and the second catalyst layer is substantially free from Ba.

A method for manufacturing a catalyst includes depositing a catalyst slurry containing at least a catalyst metal and water on a support, depositing particles of a water-absorbing polymer on a surface of the catalyst slurry, expanding the particles to a predetermined size with the water present in the catalyst slurry, and firing the support having the catalyst slurry and the particles deposited on the catalyst slurry.

A catalyst support for induction heating includes: a honeycomb structure including a pillar shaped honeycomb structure portion having: an outer peripheral wall; and a partition wall disposed on an inner side of the outer peripheral wall, the partition wall defining a plurality of cells, each of the cells extending from an end face on an inlet side to an end face on an outlet side in a gas flow direction to form a flow path; a catalyst supported onto an interior of the partition wall; and at least one magnetic body provided within the honeycomb structure, wherein the catalyst support has a region A where the catalyst is not supported, at least on the end face side of the catalyst support on the inlet side in the gas flow direction, and wherein the magnetic body is arranged at least in the region A in the gas flow direction.

A catalyst based on a zeolite of AFX structural type and on at least one transition metal, can be prepared by a process comprising at least the following steps: i) mixing, in an aqueous medium, of at least one source of silicon in oxide form SiO2, of at least one source of aluminium in oxide form Al2O3, of an organic nitrogen-comprising compound R, of at least one source of at least one alkali metal and/or alkaline-earth metal M until a homogeneous precursor gel is obtained; ii) hydrothermal treatment of said precursor gel to obtain a crystallized solid phase, iii) at least one ion exchange with a transition metal; iv) heat treatment. The catalyst can be used for the selective reduction of NOx employing the catalyst, and can achieve an NOx conversion (conversion=(NOx inletNOx outlet)/NOx inlet) of 100% at a temperature of 430 C. or lower.

A diffuser nozzle for a gas turbine engine includes a housing disposed about a nozzle axis and extending between a first nozzle end and a second nozzle end. The housing defines a nozzle duct. A plurality of walls is disposed within the nozzle duct. The plurality of walls subdivides the nozzle duct into a plurality of duct sections. The plurality of walls further defines a plurality of axially-extending duct segments of the nozzle duct such that within a first axially-extending duct segment, the duct cross-sectional area of a first duct section of the plurality of duct sections is greater than the duct cross-sectional area of each other duct section and within a second axially-extending duct segment, the duct cross-sectional area of a second duct section of the plurality of duct sections is greater than the duct cross-sectional area of each other duct section.

A NO.sub.x adsorber catalyst and its use in an emission treatment system for internal combustion engines, is disclosed. The NO.sub.x adsorber catalyst comprises a first layer consisting essentially of a support material, one or more platinum group metals disposed on the support material, and a NO.sub.x storage material.