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.

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 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 composition comprises a support material, one or more platinum group metals disposed on the support material, and a NO.sub.x storage material.

Provided are a novel form of AEI zeolite, a novel synthesis technique for producing pure phase AEI zeolite, a catalyst comprising the AEI zeolite in combination with a metal, and methods of using the same. The AEI aluminosilicate zeolite has a cuboid morphology and a silica-to-alumina ratio of 20 to 50.

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.

There is provided an exhaust gas purification system that allows efficient purification of NOx present in exhaust gas emitted from an internal combustion engine. The exhaust gas purification system of the disclosure comprises a first exhaust gas purification device that purifies exhaust gas emitted from an internal combustion engine, wherein the atmosphere alternately switches between a reducing agent-excess atmosphere and an oxidizing agent-excess atmosphere with respect to the stoichiometric atmosphere, and a second exhaust gas purification device that further purifies the exhaust gas that has been purified by the first exhaust gas purification device, wherein the first exhaust gas purification device has a three-way catalyst, and the second exhaust gas purification device has an exhaust gas purifying catalyst that comprises an AMn.sub.2O.sub.4 spinel-type oxide support (A=Mg, Zn or Li) on which a precious metal is supported.

A particulate filter includes a base material having a wall-flow structure including porous partition walls partitioning inlet and outlet cells, and wash-coating layers held inside partition walls. The wash-coating layers include inlet layers each formed from vicinity of an end portion at exhaust gas inflow side to have predetermined length and thickness and outlet layers each formed from vicinity of end portion at exhaust gas outflow side to have a predetermined length and thickness. The inlet and the outlet layers partially overlap with each other. Inlet layers of particulate filter contain substantially no noble metal catalyst, and outlet layers contain noble metal catalyst. Accordingly, PM collection performance can be easily enhanced in inlet region, and high gas distributability (pressure loss suppression performance) can be maintained in outlet region. Accordingly, it is possible to provide particulate filter capable of achieving high levels of PM collection performance and pressure loss suppression performance.

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 composition comprises a support material, one or more platinum group metals disposed on the support material, and a NO.sub.x storage material.

An electrochemical reactor is arranged inside an exhaust passage of an internal combustion engine and is provided with a plurality of groups of cells. Each group of cell has a plurality of cells, each cell has an ion conducting solid electrolyte layer, and an anode layer and cathode layer arranged on a surface of the solid electrolyte layer. Each group of cells is configured so that all of the exhaust gas flows into passages defined by cells configuring the group of cells and so that both of the anode layers and the cathode layers are exposed to each passage. The plurality of groups of cells are arranged aligned in a direction of flow of exhaust gas and different groups of cells are connected to a power source in parallel with each other.