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.

A passive NO.sub.x adsorber is disclosed. The passive NO.sub.x adsorber is effective to adsorb NO.sub.x at or below a low temperature and release the adsorbed NO.sub.x at temperatures above the low temperature. The passive NO.sub.x adsorber comprises a noble metal and a molecular sieve having an LTL Framework Type. The invention also includes an exhaust system comprising the passive NO.sub.x adsorber, and a method for treating exhaust gas from an internal combustion engine utilizing the passive NO.sub.x adsorber.

Accordingly, the present invention provides a catalyst composition suitable for converting light naphtha comprising one or more of C5 to C8 carbon atoms to aromatic compounds ranging from C6 to C10 carbon atoms, said catalyst composition comprising: (a) a medium pore size zeolite; (b) 0.1 to 5.0 wt % of zinc; and (c) 0.1 to 5 wt % of gallium. Also, the present invention provides a process for converting light naphtha comprising one or more of C5 to C8 carbon atoms to aromatic compounds ranging from C6 to C10 carbon atoms, said process comprising the step of contacting a feedstock comprising the light naphtha with a catalyst composition comprising (a) a medium pore size zeolite; (b) 0.1 to 5.0 wt % of zinc; and (c) 0.1 to 5 wt % of gallium in presence of carrier gas at temperatures ranging from 400 to 600 C.

Accordingly, the present invention provides a catalyst composition suitable for converting light naphtha comprising one or more of C5 to C8 carbon atoms to aromatic compounds ranging from C6 to C10 carbon atoms, said catalyst composition comprising: (a) a medium pore size zeolite; (b) 0.1 to 5.0 wt % of zinc; and (c) 0.1 to 5 wt % of gallium. Also, the present invention provides a process for converting light naphtha comprising one or more of C5 to C8 carbon atoms to aromatic compounds ranging from C6 to C10 carbon atoms, said process comprising the step of contacting a feedstock comprising the light naphtha with a catalyst composition comprising (a) a medium pore size zeolite; (b) 0.1 to 5.0 wt % of zinc; and (c) 0.1 to 5 wt % of gallium in presence of carrier gas at temperatures ranging from 400 to 600 C.

A method of making and using a new family of crystalline microporous metalloalumino(gallo)phosphosilicate molecular sieves is disclosed. These molecular sieves have been synthesized and are designated high charge density (HCD) MeAPSOs. These metalloalumino(gallo)phosphosilicates are represented by the empirical formula of:

R.sup.p+.sub.rA.sup.+.sub.mM.sup.2+.sub.wE.sub.xPSi.sub.yO.sub.z

where A is an alkali metal such as potassium, R is at least one quaternary ammonium cation such as ethyltrimethylammonium, M is a divalent metal such as Zn and E is a trivalent framework element such as aluminum or gallium. This family of metalloalumino(gallo)phosphosilicate materials is stabilized by combinations of alkali and quaternary ammonium cations, enabling unique, high charge density compositions. The HCD MeAPSO family of materials have catalytic properties for carrying out various hydrocarbon conversion processes and separation properties for separating at least one component.

A method is provided for synthesizing molecular sieves of ITE framework type using one or more of 1-ethyl-1,3,5-trimethylpiperidinium cations and 1-ethyl-1-methyldecahydroquinolinium cations a structure directing agent.

The present invention relates to catalyst comprising one or more metal oxides and/or metalloid oxides and a zeolitic material having the CHA framework structure comprising YO.sub.2 and X.sub.2O.sub.3, wherein Y is a tetravalent element and X is a trivalent element, wherein the zeolitic material comprises one or more alkaline earth metals selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof, and wherein the framework of the zeolitic material comprised in the catalyst contains substantially no phosphorous, as well as to a process for the preparation of a catalyst comprising one or more alkaline earth metals selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof and to a catalyst obtainable therefrom. Furthermore, the present invention relates to a method for the conversion of oxygenates to olefins employing the inventive catalyst, as well as to the use of the inventive catalyst in specific applications.