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 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 catalyst article including a substrate with an inlet side and an outlet side, a first zone and a second zone, where the first zone includes a passive NOx adsorber (PNA), and an ammonia slip catalyst (ASC) comprising a platinum group metal on a support and a first SCR catalyst; where the second zone includes a catalyst selected from the group consisting of a diesel oxidation catalyst (DOC) and a diesel exotherm catalyst (DEC); and where the first zone is located upstream of the second zone. The first zone may include a bottom layer with a blend of: (1) the platinum group metal on a support and (2) the first SCR catalyst; and a top layer with a second SCR catalyst, the top layer located over the bottom layer.

A method for producing a honeycomb structure 1 having a slit 12 includes: a first step of preparing a honeycomb structure 1 being free from slit, and forming the slit 12 leaving at least a part of the outer peripheral wall 10 or the partition wall 11; after the first step, a second step of filling the slit 12 with a joining material 13; and after the second step, a third step of removing at least a part of the outer peripheral wall 10 or the partition wall 11 left in the first step to obtain the honeycomb structure 1 having the slit 12 that divides the honeycomb structure 1.

Systems and methods are provided for using size-reversing materials in vessels where direct heating is used to at least partially provide heat for reforming reactions under cyclic reforming conditions. An example of a size-reversing material is the combination of NiO and Al.sub.2O.sub.3. It has been discovered that size-reversing materials can undergo a phase transition that can assist with re-dispersion of metal at elevated temperatures. This can assist with maintaining catalytic activity for reforming over longer time periods in the presence of cyclic reforming conditions.

A three-way catalyst article, and its use in an exhaust system for compressed natural gas engines, is disclosed. The catalyst article for treating exhaust gas from compressed natural gas (CNG) engine comprising: a substrate comprising an inlet end, an outlet end with an axial length L; a first catalytic region beginning at the inlet end and extending for less than the axial length L, wherein the first catalytic region comprises a first platinum component; a second catalytic region beginning at the outlet end and extending for less than the axial length L, wherein the second catalytic region comprises a second palladium component; and a third catalytic region, wherein the third catalytic region comprises a third rhodium component.

An ammonia burner comprising an ammonia section for ammonia oxidation and a combined heat exchange section for heating a process stream, wherein said ammonia section and heat exchange section are coaxially arranged in a pressure vessel of the burner and the hot nitrogen oxides-containing effluent gas from the ammonia section is directed to a shell side of the heat exchange section so that said effluent gas transfers heat to the process stream.

The present invention relates to a stoichiometric-combustion spark-ignition engine comprising a specific exhaust gas system for reducing harmful exhaust gases resulting from the combustion process. The exhaust gas system consists in the through-flow direction of a three-way catalytic converter close to the engine, an oxidation catalyst and a gasoline particulate filter.

The present invention relates to a catalyst for the oxidation of hydrocarbon and the selective catalytic reduction of nitrogen oxides, the catalyst comprising a substrate comprising an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end and a plurality of passages defined by internal walls of the substrate extending therethrough; and a coating disposed on the surface of the internal walls of the substrate, wherein the surface de-fines the interface between the passages and the internal walls, wherein the coating comprises a platinum group metal component supported on a first oxidic material and further comprises a mixed oxide of vanadium and one or more of iron, erbium, bismuth, cerium, europium, gadolinium, holmium, lanthanum, lutetium, neodymium, praseodymium, promethium, samarium, scandium, terbium, thulium, ytterbium, yttrium, molybdenum, tungsten, manganese, cobalt, nickel, copper, aluminum and antimony, wherein the mixed oxide is supported on a second oxidic material.

Disclosed are a three-way catalyst product, and the use thereof in an exhaust system for an internal combustion engine. The catalyst product for exhaust gas treatment contains a carrier comprising an inlet end and an outlet end and having an axial length L; a first catalytic region starting from the inlet end and extending by a length less than the axial length L, wherein the first catalytic region contains a first palladium component; a second catalytic region starting from the outlet end and extending by a length less than the axial length L, wherein the second catalytic region contains a second palladium component; and a third catalytic region starting from the outlet end and extending by a length less than the axial length L, wherein the third catalytic region contains a third rhodium component, and the third catalytic region is stacked on the second catalytic region.