A xenon adsorbent capable of efficiently adsorbing xenon, even at a low concentration, from a mixture gas is Provided. A xenon adsorbent comprising a zeolite having a pore size in the range of 3.5 to 5 Å and a silica alumina molar ratio in the range of 10 to 30.

The present invention relates to a process for preparing a zeolitic material having a framework type FER and having a framework structure comprising silicon, aluminum, and oxygen, said process comprising (i) preparing an aqueous synthesis mixture comprising water; a zeolitic material having a framework type other than FER and having a framework structure comprising silicon, aluminum, and oxygen; a source of silicon other than the zeolitic material having a framework type other than FER; an organic structure directing agent comprising piperidine; a source of an alkali metal; and a source of a base; (ii) subjecting the aqueous synthesis mixture prepared according to (i) to hydrothermal synthesis conditions comprising heating the synthesis mixture to a temperature in the range of from 140 to 190° C. and keeping the synthesis mixture at a temperature in this range under autogenous pressure, obtaining a mother liquor comprising a solid material which comprises the zeolitic material having a framework type FER.

SCR-active molecular-sieve based catalysts with improved low-temperature performance are made by heating a molecular-sieve in a non-oxidizing atmosphere with steam (hydrothermal treatment), or in a reducing atmosphere without steam (thermal treatment), at a temperature in the range of 600-900° C. for a time period from 5 minutes to two hours. The resulting SCR-active iron-containing molecular sieves exhibit a selective catalytic reduction of nitrogen oxides with NH.sub.3 or urea at 250° C. that is at least 50% greater than if the iron-containing molecular-sieve were calcined at 500° C. for two hours without performing the hydrothermal or thermal treatment.

SCR-active molecular-sieve based catalysts with improved low-temperature performance are made by heating a molecular-sieve in a non-oxidizing atmosphere with steam (hydrothermal treatment), or in a reducing atmosphere without steam (thermal treatment), at a temperature in the range of 600-900° C. for a time period from 5 minutes to two hours. The resulting SCR-active iron-containing molecular sieves exhibit a selective catalytic reduction of nitrogen oxides with NH.sub.3 or urea at 250° C. that is at least 50% greater than if the iron-containing molecular-sieve were calcined at 500° C. for two hours without performing the hydrothermal or thermal treatment.

The present disclosure provides a method of synthesizing an aluminosilicate molecular sieve by a crystal seed-assisted method, a natural aluminosilicate clay mineral treated and activated by an alkali is used as a crystal seed for synthesis of the aluminosilicate molecular sieve, and the target molecular sieve product is synthesized by hydrothermal crystallization, wherein the synthesis process does not require addition of conventional crystal seeds of a molecular sieve or use of any organic template agent, thus the synthesized product does not require a calcination process to remove the template agent. The method of synthesizing an aluminosilicate molecular sieve by a crystal seed-assisted method can meet the requirements of both crystallinity and nucleation time, and greatly reduce costs of synthesizing the aluminosilicate molecular sieve, and reduce the environmental pollution caused by removal of the template agent by calcinating.

The present disclosure provides a method of synthesizing an aluminosilicate molecular sieve by a crystal seed-assisted method, a natural aluminosilicate clay mineral treated and activated by an alkali is used as a crystal seed for synthesis of the aluminosilicate molecular sieve, and the target molecular sieve product is synthesized by hydrothermal crystallization, wherein the synthesis process does not require addition of conventional crystal seeds of a molecular sieve or use of any organic template agent, thus the synthesized product does not require a calcination process to remove the template agent. The method of synthesizing an aluminosilicate molecular sieve by a crystal seed-assisted method can meet the requirements of both crystallinity and nucleation time, and greatly reduce costs of synthesizing the aluminosilicate molecular sieve, and reduce the environmental pollution caused by removal of the template agent by calcinating.

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.

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.

The present application provides a ZSM-35 molecular sieve and a preparation method thereof. The ZSM-35 molecular sieve is an aggregated ZSM-35 molecular sieve having a hierarchical macro-meso-microporous pore structure. Raw materials for the preparation method do not include an organic template agent and a crystal seed, and the preparation method includes the following steps: preparing a reactant gel where a molar ratio of SiO.sub.2, Al.sub.2O.sub.3, Na.sub.2O, K.sub.2O, oxygen-containing acid radical and H.sub.2O is (20-40):1.0:(1.5-2.0):(4.0-6.5):(1.0-4.0):(600-1200); sequentially performing an aging treatment and a crystallization treatment on the reactant gel, washing and drying a resulting synthetic product. The ZSM-35 molecular sieve provided by the present application may be obtained by synthesizing without using an organic template agent and crystal seed, and because it has a hierarchical pore structure, it is favorable for material diffusion and mass transfer.

The present application provides a ZSM-35 molecular sieve and a preparation method thereof. The ZSM-35 molecular sieve is an aggregated ZSM-35 molecular sieve having a hierarchical macro-meso-microporous pore structure. Raw materials for the preparation method do not include an organic template agent and a crystal seed, and the preparation method includes the following steps: preparing a reactant gel where a molar ratio of SiO.sub.2, Al.sub.2O.sub.3, Na.sub.2O, K.sub.2O, oxygen-containing acid radical and H.sub.2O is (20-40):1.0:(1.5-2.0):(4.0-6.5):(1.0-4.0):(600-1200); sequentially performing an aging treatment and a crystallization treatment on the reactant gel, washing and drying a resulting synthetic product. The ZSM-35 molecular sieve provided by the present application may be obtained by synthesizing without using an organic template agent and crystal seed, and because it has a hierarchical pore structure, it is favorable for material diffusion and mass transfer.