Provided is a system for treating a flowing exhaust gas comprising a lean NOx trap, a catalyzed soot filter, an ammonia or an ammonia precursor metering system for metering ammonia or an ammonia precursor into the flowing exhaust gas; and an SCR catalyst, wherein the SCR catalyst is disposed downstream of the lean NOx trap and comprises copper and/or iron supported on a small pore molecular sieve.

An apparatus and method for producing hydrocarbons including aromatic hydrocarbons and/or lower olefins including propylene from CO H.sub.2 while inhibiting reduction in catalyst activity and enhancing selectivity. The apparatus produces hydrocarbons including aromatic hydrocarbons having 6-10 carbon atoms and/or lower olefins including propylene, and is provided: a first supply unit which supplies a raw material gas containing CO and H.sub.2; and a hydrocarbon production unit to which the raw material gas is supplied from the first supply unit, and which produces the hydrocarbons from CO and H.sub.2 contained in the raw material gas while heating a catalyst structure at a temperature of 150° C. or more and less than 300° C. or at a temperature of 350° C. or more and less than 550° C., the catalyst structure includes supports having a porous structure and including a zeolite-type compound, and a metal fine particle present in the supports, the supports have channels communicating with outside the supports, and a portion of the channels have an average inner diameter of 0.95 nm or less.

An apparatus and method for producing hydrocarbons including aromatic hydrocarbons and/or lower olefins including propylene from CO H.sub.2 while inhibiting reduction in catalyst activity and enhancing selectivity. The apparatus produces hydrocarbons including aromatic hydrocarbons having 6-10 carbon atoms and/or lower olefins including propylene, and is provided: a first supply unit which supplies a raw material gas containing CO and H.sub.2; and a hydrocarbon production unit to which the raw material gas is supplied from the first supply unit, and which produces the hydrocarbons from CO and H.sub.2 contained in the raw material gas while heating a catalyst structure at a temperature of 150° C. or more and less than 300° C. or at a temperature of 350° C. or more and less than 550° C., the catalyst structure includes supports having a porous structure and including a zeolite-type compound, and a metal fine particle present in the supports, the supports have channels communicating with outside the supports, and a portion of the channels have an average inner diameter of 0.95 nm or less.

Provided is a honeycomb catalyst in which a plurality of through holes are provided in proximity to each other in a row arrangement in the lengthwise direction, and are set apart by partitions. A honeycomb unit contains at least two types of inorganic particles and an inorganic binder. The inorganic particles contain zeolite having an SiO2/Al2O3 composition ratio of less than 15 and a CHA structure and an oxide other than zeolite, which has a positive thermal expansion coefficient. The ratio (X:Y) of the volume (X) of zeolite and the volume (Y) of oxide is 50:50 to 80:20. A displacement amount of absorbed water is reduced and cracking is controlled while maintaining high NOx purging performance.

Provided is a honeycomb catalyst in which a plurality of through holes are provided in proximity to each other in a row arrangement in the lengthwise direction, and are set apart by partitions. A honeycomb unit contains at least two types of inorganic particles and an inorganic binder. The inorganic particles contain zeolite having an SiO2/Al2O3 composition ratio of less than 15 and a CHA structure and an oxide other than zeolite, which has a positive thermal expansion coefficient. The ratio (X:Y) of the volume (X) of zeolite and the volume (Y) of oxide is 50:50 to 80:20. A displacement amount of absorbed water is reduced and cracking is controlled while maintaining high NOx purging performance.

A catalyst article having an extruded support having a plurality of channels through which exhaust gas flows during operation of an engine, and a single layer coating or a bi-layer coating on the support, where the extruded support contains a third SCR catalyst, the single layer coating and the bilayer-coating contain platinum on a support with low ammonia storage and a first SCR catalyst. The catalytic articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases and in reducing the amount of ammonia slip. Methods for producing such articles are described. Methods of using the catalytic articles in an SCR process, where the amount of ammonia slip is reduced, are also described.

A catalyst article having an extruded support having a plurality of channels through which exhaust gas flows during operation of an engine, and a single layer coating or a bi-layer coating on the support, where the extruded support contains a third SCR catalyst, the single layer coating and the bilayer-coating contain platinum on a support with low ammonia storage and a first SCR catalyst. The catalytic articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases and in reducing the amount of ammonia slip. Methods for producing such articles are described. Methods of using the catalytic articles in an SCR process, where the amount of ammonia slip is reduced, are also described.

The problem to be solved by the present invention is to provide a good NOx selective reduction catalyst. To solve the problem is a NOx selective reduction catalyst containing a composite oxide of Ti, Ce, W, and P or S.

The problem to be solved by the present invention is to provide a good NOx selective reduction catalyst. To solve the problem is a NOx selective reduction catalyst containing a composite oxide of Ti, Ce, W, and P or S.

According to one or more embodiments described, a zeolite supported catalyst may be synthesized by a process that includes combining a colloidal mixture with a metal oxide support material to form a support precursor material, processing the support precursor material to form a support material, and impregnating the support material with one or more metals to form the zeolite supported catalyst. The colloidal mixture may include nano-sized zeolite crystals, and the nano-sized zeolite crystals may have an average size of less than 100 nm.