Disclosed herein is a new crystalline molecular sieve designated SSZ-104, its synthesis in the presence of a structure directing agent comprising N-cyclohexylmethyl-N-ethylpyrrolidinium cations, and its use as an adsorbent and a catalyst.

A synthetic aluminosilicate zeolite catalyst containing at least one catalytically active transition metal selected from the group consisting of Cu, Fe, Hf, La, Au, In, V, lanthanides and Group VIII transition metals, which aluminosilicate zeolite is a small pore aluminosilicate zeolite having a maximum ring size of eight tetrahedral atoms, wherein the mean crystallite size of the aluminosilicate zeolite determined by scanning electron microscope is >0.50 micrometer.

The invention relates to a catalyst system for reducing nitrogen oxides, which comprises a nitrogen oxide storage catalyst and an SCR catalyst, wherein the nitrogen oxide storage catalyst consists of at least two catalytically active washcoat layers on a supporting body, wherein a lower washcoat layer A contains cerium oxide, an alkaline earth compound and/or alkali compound, as well as platinum and palladium, and an upper washcoat layer B, which is arranged over the washcoat layer A, contains cerium oxide, platinum and palladium, and no alkali compound and no alkaline earth compound. The invention also relates to a method for converting NOx in exhaust gases of motor vehicles that are operated by means of engines that are operated in a lean manner.

Provided are a novel synthesis technique for producing pure phase aluminosilicate zeolite and a catalyst comprising the phase pure zeolite in combination with a metal, and methods of using the same. The pure phase aluminosilicate zeolite can be selected from those having an ITW framework and a silica to alumina ratio of less than about 140 or, an STW framework and a silica to alumina ratio less than about 100.

An exhaust system for a combustion engine includes first and second catalytic converters arranged downstream of the combustion engine in a flow direction of exhaust gas. First and second exhaust pipes extend from the combustion engine to the first and second catalytic converters, respectively, with a first valve disposed in the first exhaust pipe, and a second valve disposed in the second exhaust pipe. The first and second valves operate such that in the presence of an exhaust temperature which is equal to or less than a limit value, at least the first valve opens to allow exhaust gas from the combustion engine to flow through the first catalytic converter, and that the first valve closes and the second valve opens, when the exhaust temperature is greater than the limit value to thereby allow exhaust gas from the combustion engine to flow through the second catalytic converter.

A method for determining a mass flow of ammonia between two SCR catalytic converters disposed one after the other in an SCR catalytic converter system in an exhaust system, which comprises only one reduction agent dosing unit upstream of the first SCR catalytic converter, characterized in that the determination is carried out from the signal of a NOx sensor disposed between the two SCR catalytic converters and the signal of a NOx sensor disposed downstream of the second SCR catalytic converter.

The disclosure generally provides zeolites having the CHA crystalline framework and methods of preparing the same. Provided herein are CHA zeolites containing intergrowths, a controlled framework aluminum distribution, or both. Further provided are CHA zeolites wherein crystals of the zeolite material have a predominantly flake-like morphology as determined by scanning electron microscopy (SEM). Further provided are catalyst compositions, articles, and systems including CHA zeolites promoted with a metal.

A device for supplying ammonia with solid adblue includes a urea tank, a gasholder, a heating apparatus, a mixing mechanism, a one-way valve, a first temperature sensor, a second temperature sensor, a first baroceptor, a controller. The mixing mechanism includes a first pipe, second pipe a third pipe, and media. The device is easy to has the same temperature everywhere, and then the heat distribution of the urea tank can be evenly, thus the effectiveness about the heating apparatus is elevated.

A method of calculating an ammonia (NH3) mass generated in a lean NOx trap (LNT) of an exhaust purification device includes sequentially calculating a NH3 mass flow at a downstream of each slice from a first slice to an n-th slice, and integrating the NH3 mass flow at the downstream of the n-th slice over a predetermined time, wherein the calculation of the NH3 mass flow at the downstream of the i-th slice comprises calculating a NH3 mass flow flowing into the i-th slice, calculating a NH3 mass flow generated at the i-th slice, and adding the NH3 mass flow generated at the i-th slice to a value obtained by subtracting the NH3 mass flow used to reduce the NOx and the O2 at the i-th slice from the NH3 mass flow flowing into the i-th slice.

An exhaust gas post treatment system for an internal combustion engine, in particular a heavy fuel oil-powered engine, including an SCR catalyst, using ammonia as a reducing agent for the denitration of the exhaust gas, and a device positioned upstream of the SCR catalyst by which ammonia or an ammonia precursor substance, which is converted to ammonia, introduced upstream of the SCR catalyst. Downstream of the SCR catalyst an exhaust gas scrubber is positioned, by which excess ammonia, contained in the exhaust gas leaving the SCR catalyst, together with sulfur oxides, can be scrubbed out of the exhaust gas forming ammonium salts while maintaining a pH value of approximately 6. For the control thereof, a bypass around the SCR catalyst can be provided as a westgate, or comprising an additional SCR catalyst.