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 manufacturing method includes a step of mixing a coarse particle zeolite, a fine particle zeolite, and a raw material of an inorganic bonding material to prepare a zeolite raw material; a step of forming the prepared zeolite raw material into a honeycomb shape to prepare a honeycomb formed body; and a step of firing the prepared honeycomb formed body to prepare the honeycomb structure. In the step of preparing the zeolite raw material, as the coarse particle zeolite, a chabazite type zeolite having a specific average particle diameter, the fine particle zeolite having a specific average particle diameter, the raw material of the inorganic bonding material which includes at least basic aluminum lactate is used.

Hydrocarbon (HC) traps are disclosed. The HC trap may include a first zeolite material having an average pore diameter of at least 5.0 angstroms and configured to trap hydrocarbons from an exhaust stream and to release at least a portion of the trapped hydrocarbons at a temperature of at least 225° C. The HC trap may also include a second zeolite material having an average pore diameter of less than 5.0 angstroms or larger than 7.0 angstroms. One or both of the zeolite materials may include metal ions, such as transition, Group 1A, or platinum group metals. The HC trap may include two or more discrete layers of zeolite materials or the two or more zeolite materials may be mixed. The multiple zeolite HC trap may form coke molecules having a relatively low combustion temperature, such as below 500° C.

An AFI-CHA hybrid crystal molecular sieve and an NH.sub.3-SCR catalyst using the AFI-CHA hybrid crystal molecular sieve as a carrier, and preparation methods thereof are disclosed. The AFI-CHA hybrid crystal molecular sieve includes an AFI-type SAPO-5 molecular sieve and a CHA-type SAPO-34 molecular sieve, with hybrid crystal grains of AFI and CHA. The hybrid crystal molecular sieve is synthesized by a hydrothermal synthesis method and can be obtained by changing the structure directing agent, the heating rate and the calcinating temperature in the preparation process. Further, copper is loaded on the basis of the hybrid crystal molecular sieve to prepare copper-based NH.sub.3-SCR catalyst and corresponding monolithic catalyst. The catalytic activity and hydrothermal stability of the catalyst are significantly improved by the hybrid crystal molecular sieve.

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.

Synthesis of the silicoaluminophosphate and metal silicoaluminophosphate polymorphs of the molecular sieve SAPO-18 using cyclic quaternary ammoniums as organic structure-directing agents (OSDA) and use thereof as a catalyst.

The present disclosure provides catalyst compositions for NOx conversion and catalytic articles incorporating such catalyst compositions. Certain catalyst compositions include a zeolite with a silica-to-alumina ratio from 5 to 20 and sufficient Cu exchanged into cation sites of the zeolite such that the zeolite has a Cu/Al ratio of 0.1 to 0.5 and a CuO loading of 1 to 15 wt. %; and a copper trapping component in a concentration in the range of 1 to 20 wt. %, the copper trapping component including a plurality of particles having a particle size of about 0.5 to 20 microns. Certain catalyst compositions include, as the copper trapping component, alumina present as a plurality of alumina particles with a D.sub.90 particle size distribution in the range of 0.5 microns to 20 microns.

The present disclosure relates to a method for forming a catalyst article comprising: (a) forming a slurry having a solids content of up to 50 wt % by mixing together at least the following components a crystalline molecular sieve in an H.sup.+ or NH.sub.4.sup.+ form, an insoluble active metal precursor and an aqueous solvent at a temperature in the range 10 to 35° C.; (b) coating a substrate with the slurry formed in step (a); and (c) calcining the coated substrate formed in step (b) to form a catalyst layer on the substrate. The present disclosure further relates to a catalyst article, particularly a catalyst article which is suitable for use in the selective catalytic reduction of nitrogen oxides, and to an exhaust system.

A process for preparing C.sub.2 to C.sub.5 olefins includes introducing a feed stream comprising hydrogen and at least one carbon-containing component selected from the group consisting of CO, CO.sub.2, and mixtures thereof into a reaction zone. The feed stream is contacted with a hybrid catalyst in the reaction zone, and a product stream is formed that exits the reaction zone and includes C.sub.2 to C.sub.5 olefins. The hybrid catalyst includes a methanol synthesis component and a solid microporous acid component that is selected from molecular sieves having 8-MR access and having a framework type selected from the group consisting of CHA, AEI, AFX, ERI, LTA, UFI, RTH, and combinations thereof. The methanol synthesis component comprises a metal oxide support and a metal catalyst. The metal oxide support includes titania, zirconia, hafnia or mixtures thereof, and the metal catalyst includes zinc.

A hydrocarbon removal system according an embodiment of the present invention includes: a first area including a first hydrocarbon adsorption catalyst having a first pore size; and a second area including a second hydrocarbon adsorption catalyst having a second pore size, wherein the first pore size may be smaller than the second pore size, the first hydrocarbon adsorption catalyst may include CHA zeolite, and the second hydrocarbon adsorption catalyst may include ZSM-5 zeolite.