Catalysts and methods for use in conversion of glycerides and free fatty acids to biodiesel are described. A batch or continuous process may be used with the catalysts for transesterification of triglycerides with an alkyl alcohol to produce corresponding mono carboxylic acid esters and glycerol in high yields and purity. Similarly, alkyl and aryl carboxylic acids and free fatty acids are also converted to corresponding alkyl esters. Catalysts are capable of simultaneous esterification and transesterification under same process conditions. The described catalysts are thermostable, long lasting, and highly active.

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.

This invention relates to a hydrogen spillover-based catalyst and use thereof, wherein a hydrogen activation metal cluster is dispersed in the form of being encapsulated in a crystalline or amorphous aluminosilicate matrix which is partially or fully structurally collapsed zeolite, thereby exhibiting high hydroprocessing or dehydrogenation activity and suppressed CC hydrogenolysis activity.

This invention relates to a hydrogen spillover-based catalyst and use thereof, wherein a hydrogen activation metal cluster is dispersed in the form of being encapsulated in a crystalline or amorphous aluminosilicate matrix which is partially or fully structurally collapsed zeolite, thereby exhibiting high hydroprocessing or dehydrogenation activity and suppressed CC hydrogenolysis activity.

In an embodiment, the present disclosure pertains to a composition comprising a zeolite with high silica content. In some embodiments, the silica to aluminum ratio (SAR) for the zeolite is 2:1. In some embodiments, the zeolite comprises Zeolite HOU-2 (LTA-type). In some embodiments, the silica to aluminum ratio (SAR) for the zeolite is >3. In some embodiments, the zeolite comprises Zeolite HOU-3 (FAU type). In some embodiments, the zeolite is synthesized using a one-step method. In some embodiments, the zeolite is synthesized without the use of an organic structure-directing agent (OSDA). In some embodiments, the zeolite is synthesized without the use of post-synthesis dealumination. In some embodiments, the zeolite is synthesized without the use crystal seeds. In some embodiments, the zeolite is used in commercial ion exchange. In some embodiments, the zeolite is used for catalysis reaction. In some embodiments, the zeolite is highly thermostable.

In an embodiment, the present disclosure pertains to a composition comprising a zeolite with high silica content. In some embodiments, the silica to aluminum ratio (SAR) for the zeolite is 2:1. In some embodiments, the zeolite comprises Zeolite HOU-2 (LTA-type). In some embodiments, the silica to aluminum ratio (SAR) for the zeolite is >3. In some embodiments, the zeolite comprises Zeolite HOU-3 (FAU type). In some embodiments, the zeolite is synthesized using a one-step method. In some embodiments, the zeolite is synthesized without the use of an organic structure-directing agent (OSDA). In some embodiments, the zeolite is synthesized without the use of post-synthesis dealumination. In some embodiments, the zeolite is synthesized without the use crystal seeds. In some embodiments, the zeolite is used in commercial ion exchange. In some embodiments, the zeolite is used for catalysis reaction. In some embodiments, the zeolite is highly thermostable.

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 disclosure provides a molecular sieve, a sound absorbing material using the molecular sieve, and a speaker. The molecular sieve is a core-shell molecular sieve. The core-shell molecular sieve includes a core phase molecular sieve and a shell layer molecular sieve. The shell layer molecular sieve has a greater average pore diameter than the core phase molecular sieve. The porous shell layer molecular sieve having the greater pore diameter can protect the internal functioning micropores from being blocked, so that a resonant frequency f.sub.0 of a same volume of molecular sieve can be reduced, the bass effect and performance stability are significantly improved.

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.

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.