A NaY molecular sieve with an aluminum-rich surface is prepared using a process that includes the steps of: a. mixing a directing agent and a first silicon source to obtain a first mixture, wherein the directing agent has a molar composition of Na.sub.2O:Al.sub.2O.sub.3:SiO.sub.2:H.sub.2O=(6-25):1:(6-25):(200-400); b. mixing the first mixture obtained in the step a with a second silicon source, an aluminum source and water to obtain a second mixture; c. carrying out hydrothermal crystallization on the second mixture obtained in the step b, and collecting a solid product. Calculated as SiO.sub.2, the weight ratio of the first silicon source to the second silicon source is 1:(0.01-12). The NaY molecular sieve has larger aluminum distribution gradient from the surface to the center of the particle than the conventional molecular sieve.

To provide a technique enabling the effective use of a plant-derived Si source. The present technique is capable of providing a production method of a porous material containing Si and Al, in which a first Si source composition that is a plant-derived Si source and an Al source are used as at least raw materials. The first Si source composition may be a Si source recovered when a treatment for recovering the Si source is carried out after a carbonization treatment of a plant-derived raw material. A second Si source composition may be a treatment product obtained by a decarburization treatment of a plant-derived raw material.

Membranes, methods of making the membranes, and methods of using the membranes are described herein. The membranes can comprise a gas permeable support and a continuous phase comprising a selective inorganic material disposed within the gas permeable support. In some embodiments, the membranes can exhibit a CO.sub.2:N.sub.2 selectivity of at least 10 at 24° C. The membranes can be bendable, such that when the membranes are wrapped around a 1.5-inch diameter cylinder and returned to a planar conformation, the CO.sub.2:N.sub.2 selectivity of the membranes is at least 25% of the CO.sub.2:N.sub.2 selectivity of the membranes prior to having been wrapped around the cylinder.

The present invention relates to a zeolite material in the form of FAU zeolite nanocrystal aggregates, to the method for preparing said material, to the zeolite agglomerates prepared from said material with a binder, and to the uses of said material and agglomerate as adsorbents for gas-phase or liquid-phase separation operations, and particularly in methods for separating gas or liquid flows.

A method for preparing a NaY molecular sieve having a high silica-to-alumina ratio, wherein deionized water, a silicon source, an aluminum source, an alkali source, and ILs as a template agent are mixed to obtain an initial gel mixture; the initial gel mixture is maintained at a proper temperature and aged, then fed into a high pressure synthesis kettle for crystallization; the solid product is separated and dried, to obtain the NaY molecular sieve having a high silica-to-alumina ratio, wherein the ILs is a short-chain alkylimidazolium ionic liquid, the template agent is less volatile, and the resultant high-silicon Y molecular sieve has a high crystallinity and a silica-to-alumina ratio of 6 or more.

Disclosed in the present application is a high-silica Y molecular sieve having FAU topology. The anhydrous chemical constitution of the molecular sieve is as shown in formula I: kM.mR1.nR2.(Si.sub.xAl.sub.y)O.sub.2 Formula I; wherein, M is at least one of alkali metal elements; R1 and R2 represent organic templating agent agents; k represents the numbers of moles of the alkali metal element corresponding to per mole of (Si.sub.xAl.sub.y)O.sub.2, k=0˜0.20; m and n represent the numbers of moles of templating agents R1 and R2 corresponding to per mole of (Si.sub.xAl.sub.y)O.sub.2, m=0˜0.20, n=0.01˜0.20; x, y respectively represents the mole fraction of Si and Al, 2x/y=7-40, and x+y=1; R1, R2 are independently selected from one of nitrogen-containing heterocyclic compounds and their derivatives, and quaternary ammonium compounds. Also disclosed in the present application is a synthesis method for the high-silica Y molecular sieve having FAU topology.

A method for preparing a zeolite molecular sieve includes the steps of: (1) mixing at least one of a silicon source, an aluminum source and a phosphorus source with an alkaline substance, a template agent and water uniformly to obtain a zeolite molecular sieve precursor solution; aging the zeolite molecular sieve precursor solution at 20-30° C. for 10-15 h; and subjecting the aged solution to ionizing radiation, and then washing the obtained solid to neutrality and drying to obtain the zeolite molecular sieve. The method of the present invention is green, simple and extremely cost-effective. Under the irradiation of an ionizing radiation source, the synthesis period of zeolite molecular sieve is short and no heating is needed in the preparation process, so energy consumption is reduced and a high-pressure system is avoided.

The present invention relates to a process for the preparation of a zeolitic material comprising YO.sub.2 in its framework structure, wherein Y stands for a tetravalent element, wherein said process comprises the steps of: (1) providing a mixture comprising one or more sources for YO.sub.2, one or more fluoride containing compounds, and one or more structure directing agents; (2) crystallizing the mixture obtained in step (1) for obtaining a zeolitic material comprising YO.sub.2 in its framework structure;
wherein the mixture provided in step (1) and crystallized in step (2) contains 35 wt.-% or less of H.sub.2O based on 100 wt.-% of YO.sub.2 contained in the mixture provided in step (1) and crystallized in step (2), as well as to a zeolitic material comprising YO.sub.2 in its framework structure obtainable and/or obtained according to said process, and to a zeolitic material per se comprising SiO.sub.2 in its framework structure, wherein in the .sup.29Si MAS NMR spectrum of the as-synthesized zeolitic material the ratio of the total integration value of the peaks associated to Q3 signals to the total integration value of the peaks associated to Q4 signals is in the range of from 0:100 to 20:80, including the use of the aforementioned zeolitic materials.

A method for manufacturing a zeolite membrane structure includes a step of forming a first zeolite membrane on a porous support by hydrothermal synthesis in a state in which the porous support is immersed in a first zeolite membrane formation solution, a step of immersing the porous support formed the first zeolite membrane for greater than or equal to 5 minutes in a second zeolite membrane formation solution at greater than or equal to 10 degrees C. and less than or equal to 70 degrees C. and greater than or equal to pH 10, and a step of forming a second zeolite membrane on the first zeolite membrane by hydrothermal synthesis in a state in which the porous support formed the first zeolite membrane is immersed in the second zeolite membrane formation solution. The first zeolite membrane and the second zeolite membrane share at least one composite building unit constituting a framework structure.

Provided is a method for preparing a Y type molecular sieve having a high silica-to-alumina ratio, comprising: mixing deionized water, a silicon source, an aluminum source, an alkali source, and a tetraalkylammoniumcation source as a template agent to obtain an initial gel mixture; after aging the initial gel mixture at an appropriate temperature, feeding the gel mixture into a high pressure synthesis kettle for crystallization; separating a solid product, and drying to obtain the Y type molecular sieve having a high silica-to-alumina ratio. The method provides a phase-pure Y type molecular sieve having a high crystallinity, the SiO.sub.2/Al.sub.2O.sub.3 thereof being not less than 6.