Disclosed herein are methods for crystallizing aluminosilicate zeolites, including the steps of preparing a mixture containing a silica source, a mineralizing agent, an organic structure directing agent; heating the mixture to form a heated mixture; and adding an alumina source to the heated mixture. The method steps described herein can provide an accelerated aluminosilicate zeolite crystallization process as compared, e.g., to conventional processes.

A catalyst includes LTA zeolite including copper ions, wherein a Si/Al ratio of the LTA zeolite is 2 to 50. The catalyst is coated on a honeycomb carrier or a filter. The catalyst removes NOx from a reaction gas at 100 C. or above. The catalyst has an NOx conversion rate of 80% at 450 C. or above.

A device for purifying exhaust gas may be provided to purify exhaust gas in an engine includes an exhaust line through which exhaust gas discharged from the engine passes, a diesel oxidation catalyst (DOC) that is disposed in the exhaust line to purify hydrocarbon (HC) and carbon monoxide (CO) of the exhaust gas, a urea injector that injects a urea aqueous solution into the exhaust line, and a selective catalyst reduction (SCR) that reduces nitrogen oxide of the exhaust gas passing through the DOC by use of the urea aqueous solution, in which the DOC includes an LTA zeolite catalyst.

A method for manufacturing a zeolite catalyst includes: manufacturing a first Linde Type A (LTA) zeolite using an LTA seed; manufacturing a second LTA zeolite including ions by substituting ions to the first LTA zeolite; and manufacturing a copper LTA zeolite by performing copper ion exchange on the second LTA zeolite.

The present invention further provides a method of making an metal-loaded aluminosilicate zeolite having a maximum pore opening defined by eight tetrahedral atoms from pre-existing aluminosilicate zeolite crystallites, wherein the metal is present in a range of from 0.5 to 5.0 wt. % based on the total weight of the metal-loaded aluminosilicate zeolite.

There is provided a zeolite which has excellent NOx purifying performance, particularly excellent NOx purifying performance after heat endurance. The zeolite has a CHA structure in which Cu and Ce are carried, and has a Cu/Al molar ratio of 0.25 to 0.48 and a Ce/Al molar ratio of 0.01 to 0.03.

A method of manufacturing a porous monolithic zeolite structure including the steps of; taking a porous monolithic substrate; forming one or more zeolites on the substrate; and substantially or completely removing the substrate.

The present invention concerns zeolites with hierarchical porosity having a molar ratio Si/Al of between 1 and 1.4, inclusive, of which the average diameter, as a number, is between 0.1 ?m and 20 ?m, having controlled and optimized crystallinity, and having mesoporosity such that the mesoporous outer surface area is between 40 m.sup.2.g.sup.?1 and 400 m.sup.2.g.sup.?1. The present invention also concerns the method for preparing said zeolites with hierarchical porosity.

The present invention concerns zeolites with hierarchical porosity having a molar ratio Si/Al of between 1 and 1.4, inclusive, of which the average diameter, as a number, is between 0.1 ?m and 20 ?m, having controlled and optimized crystallinity, and having mesoporosity such that the mesoporous outer surface area is between 40 m.sup.2.Math.g.sup.?1 and 400 m.sup.2.Math.g.sup.?1. The present invention also concerns the method for preparing said zeolites with hierarchical porosity.

A device for purifying exhaust gas may be provided to purify exhaust gas in an engine includes an exhaust line through which exhaust gas discharged from the engine passes, a diesel oxidation catalyst (DOC) that is disposed in the exhaust line to purify hydrocarbon (HC) and carbon monoxide (CO) of the exhaust gas, a urea injector that injects a urea aqueous solution into the exhaust line, and a selective catalyst reduction (SCR) that reduces nitrogen oxide of the exhaust gas passing through the DOC by use of the urea aqueous solution, in which the DOC includes an LTA zeolite catalyst.