The present invention is directed to a method of preparing a molecular sieve of SWY framework type, denominated STA-30. STA-30 is synthesized using 1,4-diazabicyclo[2.2.2]octane, 1-azabicyclo[2.2.2]octane derivates and combinations thereof as structure directing agents. The resulting molecular sieve is useful as catalysts, particularly when used in combination with exchanged transition metal(s) for the Selective Catalytic Reduction (SCR) of NO.

The present invention is directed to a method of preparing a molecular sieve of SWY framework type, denominated STA-30. STA-30 is synthesized using 1,4-diazabicyclo[2.2.2]octane, 1-azabicyclo[2.2.2]octane derivates and combinations thereof as structure directing agents. The resulting molecular sieve is useful as catalysts, particularly when used in combination with exchanged transition metal(s) for the Selective Catalytic Reduction (SCR) of NO.

A catalyst and process for the production of methyl acetate by contacting dimethyl ether and carbon monoxide in the presence of a catalyst which is a zeolite of micropore volume of 0.01 ml/g or less.

A catalyst and process for the production of methyl acetate by contacting dimethyl ether and carbon monoxide in the presence of a catalyst which is a zeolite of micropore volume of 0.01 ml/g or less.

A lower olefin by using a zeolite catalyst, a composite catalyst capable of further extending the lifetime of catalytic activity, a method for producing the composite catalyst, a method for producing a lower olefin by using the composite catalyst, and a method for regenerating a composite catalyst in the method for producing a lower olefin are provided. The composite catalyst is a catalyst for producing a lower olefin from a hydrocarbon feedstock. This composite catalyst is constituted of a zeolite being a crystalline aluminosilicate containing gallium and iron or iron and further having a framework with 8- to 12-membered ring, and of silicon dioxide. By using the composite catalyst, a lower olefin can be continuously produced over a long period of time.

A lower olefin by using a zeolite catalyst, a composite catalyst capable of further extending the lifetime of catalytic activity, a method for producing the composite catalyst, a method for producing a lower olefin by using the composite catalyst, and a method for regenerating a composite catalyst in the method for producing a lower olefin are provided. The composite catalyst is a catalyst for producing a lower olefin from a hydrocarbon feedstock. This composite catalyst is constituted of a zeolite being a crystalline aluminosilicate containing gallium and iron or iron and further having a framework with 8- to 12-membered ring, and of silicon dioxide. By using the composite catalyst, a lower olefin can be continuously produced over a long period of time.

Provided are zeolite catalysts that allow reactions to proceed at temperatures as low as possible when lower olefins are produced from hydrocarbon feedstocks with low boiling points such as light naphtha, make it possible to make propylene yield higher than ethylene yield in the production of lower olefins, and have long lifetime. The zeolite catalysts are used in the production of lower olefins from hydrocarbon feedstocks with low boiling points such as light naphtha. The zeolite catalysts are MFI-type crystalline aluminosilicates containing iron atoms and have molar ratios of iron atoms to total moles of iron atoms and aluminum atoms in the range from 0.4 to 0.7. The use of the zeolite catalysts make it possible to increase propylene yield, to lower reaction temperatures, and to extend catalyst lifetime.

Provided are zeolite catalysts that allow reactions to proceed at temperatures as low as possible when lower olefins are produced from hydrocarbon feedstocks with low boiling points such as light naphtha, make it possible to make propylene yield higher than ethylene yield in the production of lower olefins, and have long lifetime. The zeolite catalysts are used in the production of lower olefins from hydrocarbon feedstocks with low boiling points such as light naphtha. The zeolite catalysts are MFI-type crystalline aluminosilicates containing iron atoms and have molar ratios of iron atoms to total moles of iron atoms and aluminum atoms in the range from 0.4 to 0.7. The use of the zeolite catalysts make it possible to increase propylene yield, to lower reaction temperatures, and to extend catalyst lifetime.

The present disclosure provides a sound absorbing material. The sound absorbing material comprises MFI-structural-type zeolite. The MFI-structural-type zeolite comprises a framework, and the framework comprises SiO.sub.2 and AlO.sub.3, and the mass ratio of Si to Al in the framework is less than 200 and not less than 50. The present disclosure also provides a speaker box applying the sound absorbing material. The sound absorbing material provided by the present disclosure and the speaker box using the sound absorbing material can further improve the performance of the speaker box, reduce the failure of zeolite and improve the performance stability of the speaker box.

The present disclosure provides a sound absorbing material. The sound absorbing material comprising a heteroatom zeolite molecular sieve comprising a framework and an extra-framework cation, the framework comprising SiO2 and a metal oxide MxOy comprising a metal element M, wherein the framework has a molar ratio of Si/M between 250 to 500, wherein the M includes Fe, and that the extra-framework cation is at least one of a monovalent copper ion, a monovalent silver ion, a monovalent gold ion, an alkali metal ion or an alkaline earth metal ion. The sound absorbing material provided by the present disclosure, sound absorbing material to have better oxygen adsorption capacity, good waster repellency and stability. When such a sound absorbing material is applied to a speaker box, the speaker box will have better low frequency acoustic performance and better reliability.