Aluminosilicate molecular sieve with super-macroporous structure as well as synthesis method and application of aluminosilicate molecular sieve

Abstract

The invention discloses two aluminosilicate molecular sieves with super-macroporous structures, the synthetic state schematic chemical composition of the molecular sieves is rROH: a (OH <-> or F <->): xAl2O3: SiO2: wH2O, the schematic chemical composition of the molecular sieves after roasting is (HAlO2) x.SiO2, the molecular sieves are NJU120-1, and after roasting of the NJU120-1, the molecular sieves have the molecular weight of 250,000-350,000. A framework structure composed of a T (Si, Al) O4 tetrahedron has a 22 * 10 * 10 membered ring three-dimensional pore channel system, the molecular sieve is NJU120-2, and after the NJU120-2 is roasted, the framework structure composed of the T (Si, Al) O4 tetrahedron has a 22 * 12 * 10 membered ring three-dimensional pore channel system. The preparation method is reasonable in design, is a novel germanium-free, high-silicon or pure-silicon and fully-connected super-macroporous molecular sieve material, not only has very important practical application value in the fields of catalysis, adsorption separation and the like, but also has very important theoretical significance for enriching molecular sieve structure families.

Description

Technical Field

[0001] The present invention relates to the technical field of zeolite molecular sieves, and particularly to aluminosilicate molecular sieves with a super-large pore structure, as well as their synthesis methods and uses. Background Art

[0002] Zeolite molecular sieves are a class of inorganic crystalline materials with regular microporous / mesoporous channel structures. They use TO4 (where T atoms can be silicon, aluminum, phosphorus, germanium, gallium, etc.) tetrahedrons as the basic structural units, and form a regular and ordered three-dimensional framework structure through oxygen atom bridging. Different connection methods between TO4 can construct various zeolite materials with different topological configurations. Zeolite molecular sieves generally have one-dimensional or multi-dimensional channels, and the pore mouth sizes range from eight-membered rings (with a diameter of about 0.4 nm) to thirty-membered rings (with a diameter of about 1.93 nm). The structural units of the molecular sieve determine its long-range ordered porous structure, and at the same time endow the molecular sieve with excellent properties in catalysis and adsorption separation: large specific surface area, uniform pore size distribution; the pore size and acid-base properties can be adjusted by simple ion exchange; the silicon-aluminum ratio of the molecular sieve can be adjusted within a certain range by adjusting the ratio of synthesis raw materials, thereby changing the surface polarity and electric field, so as to achieve the best catalytic and adsorption separation effects. The hydrothermal synthesis method is the most common method for synthesizing molecular sieves. Usually, only the silicon source (such as silica sol), aluminum source (such as inorganic aluminum salts), alkali and water are mixed in appropriate proportions, and heated in a hydrothermal synthesis autoclave for a certain time to synthesize molecular sieve crystals. Sometimes, some organic amines need to be added as template agents to play a structure-directing role, but most of these template agents are inexpensive. The good thermal / hydrothermal stability and low synthesis cost of the molecular sieve make it the most promising catalytic and adsorption separation material to meet the industrial application requirements. A molecular sieve with a specific structure also needs to be further distinguished by X-ray powder diffraction (XRD), because different crystal structures result in different pore channel structures for different molecular sieves, and completely different diffraction patterns will be obtained in the X-ray powder diffraction test. Existing molecular sieves, such as A-type molecular sieves (US2882243), Y-type molecular sieves (US3130007), ZSM-11 molecular sieves (US3709979), ZSM-23 molecular sieves (US4076843) and ZSM-35 molecular sieves (US4016245), etc., all have their own characteristic powder X-ray diffraction patterns (XRD).

[0003] Molecular sieve materials can be divided into small-pore, medium-pore, large-pore and extra-large-pore molecular sieves according to the ring number of the pores, corresponding to window ring numbers of less than 8-membered rings, less than 10-membered rings, less than 12-membered rings and greater than 12-membered rings, respectively. The crystallization of extra-large-pore zeolite molecular sieves with more than 12-membered rings is very difficult and usually requires the participation of special organic structure-directing agents and germanium elements. For example, ITQ-37 with 30-membered rings [J. Sun et al., Nature, 2009, 458, 1154-1157], ITQ-43 with 28-membered rings [J. Jiang et al., Science, 2011, 333, 1131-1134] and NUD-1 molecular sieve with 18-membered rings (CN104370296A), etc. Germanium elements are first of all expensive, and when the molecular sieve framework contains germanium, the hydrothermal stability of the molecular sieve framework is poor, which limits the application range of germanium-containing extra-large-pore zeolite molecular sieves.

[0004] Due to the good stability of zeolite molecular sieve materials in the form of aluminosilicates and the easy control of the chemical microenvironment in the pores, they are widely used in the fields of petrochemical industry, fine chemical industry, energy conversion and storage, and biomedicine. However, the number of aluminosilicate molecular sieve materials with extra-large pores and stable framework structures is limited, such as ZEO-1 molecular sieve with 16-membered ring pores (Lin et al., Science, 2021, 374, 1605-1608.), ZEO-3 molecular sieve with 16-membered ring pores (Li et al., Science, 2023, 379, 283-287) and the recently reported ZEO-5 molecular sieve with 20-membered ring pores (Gao et al., Nature, 2024, 628, 99–103.). Both ZEO-3 and ZEO-5 have pure silicon skeletons and are not directly hydrothermally synthesized but obtained by post-treatment. Extra-large-pore aluminosilicate molecular sieves have very important practical value for processing chemical processes involving macromolecules. Summary of the Invention

[0005] The present invention provides an aluminosilicate molecular sieve with an extra-large pore structure, as well as its synthesis method and uses. It is a new type of germanium-free, high-silicon or pure-silicon extra-large-pore molecular sieve material, which not only has very important practical application value in the fields of catalysis, adsorption separation, etc., but also has very important theoretical significance for enriching the molecular sieve structure family.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] An aluminosilicate molecular sieve with an extra-large pore structure, the schematic chemical composition of the as-synthesized molecular sieve is: rROH: a(OH- or F-): xAl2O3: SiO2: wH2O, and the schematic chemical composition of the calcined molecular sieve is: (HAlO2)x ·SiO2

[0008] Preferably, the zeolite is NJU120-1. After the NJU120-1 is calcined, its framework structure composed of T(Si, Al)O4 tetrahedrons has a three-dimensional pore system with 22×10×10 yuan rings.

[0009] Preferably, the zeolite is NJU120-2. After the NJU120-2 is calcined, its framework structure composed of T(Si, Al)O4 tetrahedrons has a three-dimensional pore system with 22×12×10 yuan rings.

[0010] A method for synthesizing an aluminosilicate zeolite with a super-large pore structure, comprising the following steps:

[0011] S1, under stirring conditions, a silicon source, an aluminum source, an organic template agent, water, and an optional mineralizing agent (F - or OH - ) are mixed uniformly in proportion, and the resulting mixture forms a reaction gel. The chemical composition of the reaction gel is rROH:a(OH- or F-):xAl2O3:SiO2:wH2O, where R represents the positive charge group of the organic template agent; the value ranges of the corresponding r, a, x, and w are: r = 0.1-5.0, a = 0-5.0, x = 0-1.0, w = 1-100; the preferred value ranges of r, a, x, and w are: r = 0.1-2.0, a = 0-2.0, x = 0-0.5, w = 1-30;

[0012] S2, the reaction gel is placed under an infrared lamp or in an oven. After removing the excess solvent, the reaction gel is transferred to a stainless steel autoclave and crystallized at a temperature of 80-240 °C for 1-60 days under sealed conditions.

[0013] S3, after washing and drying the crystallized product, it is calcined in an air atmosphere at 300-850 °C for 2-5 hours to remove the template agent.

[0014] Preferably, the organic template agent has a tetrahedral spatial configuration represented by the following general formula:

[0015]

[0016] wherein, R1, R2 are phenyl, cyclohexyl or adamantyl, R3, R4 are C 1-4 alkyl (methyl, ethyl, propyl, butyl), cyclohexyl, or adamantyl, X is P (phosphorus), N (nitrogen), R1, R2 are preferably adamantyl, R3, R4 are preferably C 1-4 alkyl, and X is preferably phosphorus.

[0017] Preferably, the organic template is selected from any one or more of the following:

[0018]

[0019]

[0020] Preferably, the silicon source is selected from at least one of silicic acid, silica gel, silica sol, tetraalkyl orthosilicate, and water glass.

[0021] Preferably, the boron group element compound is selected from at least one of sodium metaaluminate, aluminum isopropoxide, aluminum sulfate hexadecahydrate, aluminum hydroxide, and boric acid.

[0022] Preferably, no more than 80% of the aluminum atoms in the molecular sieve are replaced by at least one element other than silicon and aluminum.

[0023] Preferably, the element other than silicon and aluminum is selected from at least one of the elements consisting of boron, tin, zirconium, and titanium.

[0024] Preferably, in the S1, the mineralizing agent used is selected from compounds containing F - or OH - ions.

[0025] Preferably, the mixture contains 0.01 ppm by weight to 10,000 ppm by weight of seeds.

[0026] Preferably, the seeds contain the molecular sieve described in any one of the present invention.

[0027] A molecular sieve composition comprising the molecular sieve of the present invention and a binder.

[0028] Preferably, the use of the molecular sieve composition as an adsorbent or a catalyst.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] The NJU120-1 molecular sieve has a brand-new three-dimensional pore system of 22×10×10, while the NJU120-2 molecular sieve has a brand-new three-dimensional pore system of 22×12×10. It is a new type of, germanium-free, high-silicon or pure-silicon, fully connected super-large pore molecular sieve material, which not only has very important practical application value in the fields of catalysis, adsorption separation, etc., but also has very important theoretical significance for enriching the molecular sieve structure family. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 For more specific topological features of the framework structure of the NJU120-1 molecular sieve of the present invention;

[0032] Figure 2 More specific topological features of the framework structure of the NJU120-2 molecular sieve of the present invention;

[0033] Figure 3 X-ray powder diffraction patterns (Cu target Kα radiation) of the NJU120-1 molecular sieve of the present invention before and after calcination at 600 °C to remove the template agent;

[0034] Figure 4 Schematic diagrams of the pore channels of the NJU120-1 molecular sieve crystal structure of the present invention in different directions;

[0035] Figure 5 Scanning electron micrograph (SEM) of the NJU120-1 molecular sieve of the present invention;

[0036] Figure 6 X-ray powder diffraction patterns (Cu target Kα radiation) of the NJU120-2 molecular sieve of the present invention before and after calcination at 600 °C to remove the template agent;

[0037] Figure 7 Schematic diagrams of the pore channels of the NJU120-2 molecular sieve crystal structure of the present invention in different directions;

[0038] Figure 8 Scanning electron micrograph (SEM) of the NJU120-2 molecular sieve of the present invention. Detailed Description of the Invention

[0039] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0040] Referring to Figures 1 - 8 , for aluminosilicate molecular sieves with a super-large pore structure, after being freshly synthesized, the molecular sieve may generally further contain organic substances (such as organic template agents) and water in its composition. Therefore, the schematic chemical composition of the as-synthesized molecular sieve is: rROH: a(OH⁻ or F⁻): xAl₂O₃: SiO₂: wH₂O, where R represents the positively charged group of the organic template agent. The schematic chemical composition of the molecular sieve after calcination is: (HAlO₂) x ·SiO₂, where 0 ≤ x ≤ 1, preferably x = 0 - 0.5, more preferably x = 0 - 0.2;

[0041] Example 1

[0042] The molecular sieve is NJU120-1, and its T (silicon, aluminum) atoms have the following Figure 1The topological features shown. After calcination of NJU120-1, its framework structure composed of T(Si, Al)O4 tetrahedra has a three-dimensional pore system with 22×10×10 member rings;

[0043] The molecular sieve NJU120-1 before and after calcination has the X-ray powder diffraction characteristics shown in Table A1 and Table A2 below:

[0044] Table A1 X-ray powder diffraction characteristics of NJU120-1 before calcination

[0045]

[0046] Table A2 X-ray powder diffraction characteristics of NJU120-1 after calcination

[0047]

[0048]

[0049] In the above data, w, mw, m, s, vs represent the diffraction peak intensity, where w is weak, mw is medium-weak, m is medium, s is strong, and vs is very strong, which is known to those skilled in the art. Generally, w is less than 10, mw is 10-20, m is 20-40, s is 40-70, and vs is greater than 70.

[0050] Example 2

[0051] This molecular sieve is NJU120-2, and its T (silicon, aluminum) atoms have as Figure 2 shown topological features. After calcination of NJU120-2, its framework structure composed of T(Si, Al)O4 tetrahedra has a three-dimensional pore system with 22×12×10 member rings;

[0052] NJU120-2 before and after calcination has the X-ray powder diffraction characteristics shown in Table A3 and Table A4 below:

[0053] Table A3 X-ray powder diffraction characteristics of NJU120-2 before calcination

[0054]

[0055]

[0056] Table A4 X-ray powder diffraction characteristics of NJU120-2 after calcination

[0057]

[0058] In the above data, w, mw, m, s, and vs represent the diffraction peak intensities. w means weak, mw means medium-weak, m means medium, s means strong, and vs means very strong, which is known to those skilled in the art. Generally, w is less than 10, mw is 10 - 20, m is 20 - 40, s is 40 - 70, and vs is greater than 70.

[0059] The present invention also provides a method for synthesizing an aluminosilicate molecular sieve with a supermacroporous structure, comprising the following steps:

[0060] S1, under stirring conditions, a silicon source, an aluminum source, an organic template agent, water, and an optional mineralizing agent (F - or OH - ) are mixed evenly in proportion to obtain a mixture that forms a reaction gel. The chemical composition of the reaction gel is rROH:a(OH⁻ or F⁻):xAl₂O₃:SiO₂:wH₂O, where R represents the positively charged group of the organic template agent; the value ranges of the corresponding r, a, x, and w are: r = 0.1 - 5.0, a = 0 - 5.0, x = 0 - 1.0, w = 1 - 100; the preferred value ranges of r, a, x, and w are: r = 0.1 - 2.0, a = 0 - 2.0, x = 0 - 0.5, w = 1 - 30;

[0061] Among them, as the silicon source, any silicon source conventionally used in the art for this purpose can be used. For example, silicic acid, silica gel, silica sol, tetraalkyl silicate, or water glass can be cited. These silicon sources can be used alone or in combination of multiple kinds in the required proportion;

[0062] As the mineralizing agent, it can be F⁻ ions or OH⁻ ions, and any F⁻ or OH⁻ conventionally used in the art for this purpose can be used. For example, hydrofluoric acid, ammonium fluoride, sodium hydroxide, potassium hydroxide, etc. can be cited;

[0063] As the aluminum source, any aluminum source conventionally used in the art for this purpose can be used. For example, at least one of aluminum hydroxide, sodium aluminate, aluminum salts, kaolin, and montmorillonite can be cited.

[0064] S2. Place the reaction gel under an infrared lamp or in an oven. After removing the excess solvent, transfer the reaction gel to a stainless-steel autoclave. Under sealed conditions, carry out crystallization at a temperature of 80 - 240 °C, preferably 120 - 220 °C, for 1 - 60 days, preferably 2 - 45 days, more preferably 3 to 30 days. After the crystallization is completed, the molecular sieve can be separated from the resulting reaction mixture as a product by any conventionally known separation method. In this way, molecular sieves NJU120 - 1 and NJU120 - 2, also known as molecular sieves NJU120 - 1 and NJU120 - 2 in the synthetic state form, are obtained. As the separation method, for example, a method of filtering, washing, and drying the obtained reaction mixture can be cited. Filtering, washing, and drying can be carried out in any manner conventionally known in the art.

[0065] S3. After washing and drying the crystallized product, calcine it in an air atmosphere at 300 - 850 °C for 2 - 5 hours to remove the template agent and possible moisture, etc. In this way, the calcined molecular sieve, also known as molecular sieves NJU120 - 1 and NJU120 - 2 in the calcined form, is obtained. Immediately after synthesis, the molecular sieve may generally further contain organic substances (such as organic template agents) and water in its composition. Therefore, molecular sieves NJU120 - 1 and NJU120 - 2 may also have a schematic chemical composition as shown by the formula rROH:a(OH⁻ or F⁻):xAl₂O₃:SiO₂:wH₂O, where R represents the positively charged group of the organic template agent. Here, by calcining the molecular sieve with the schematic chemical composition of "rROH:a(OH⁻ or F⁻):xAl₂O₃:SiO₂:wH₂O" to remove any organic template agent and water in its pores, a molecular sieve with the schematic chemical composition of "(HAlO₂) x ·SiO₂" can be obtained. In addition, the calcination can be carried out in any manner conventionally known in the art. For example, the calcination temperature is generally from 300 to 850, preferably 400 to 600, and the calcination time is generally 1 hour to 10 hours, preferably from 3 hours to 6 hours. In addition, the calcination is generally carried out in an oxygen-containing atmosphere, such as air or an oxygen atmosphere.

[0066] In the schematic chemical composition rROH:a(OH⁻ or F⁻):xAl₂O₃:SiO₂:wH₂O, where R represents the positively charged group of the organic template agent, the organic template agent has the following tetrahedral spatial configuration represented by the general formula:

[0067]

[0068] wherein, R1 and R2 are phenyl, cyclohexyl or adamantyl, and R3 and R4 are C 1-4Alkyl (methyl, ethyl, propyl, butyl), cyclohexyl, or adamantyl, X is P (phosphorus), N (nitrogen), R1 and R2 are preferably adamantyl, and R3 and R4 are preferably C 1-4 alkyl, and X is preferably phosphorus.

[0069] The organic template agent is selected from any one or more of the following:

[0070]

[0071]

[0072] Preferably These organic template agents can be used alone or in combination of multiple ones in the required proportions.

[0073] In molecular sieves NJU120-1 and NJU120-2, the framework Al can be partially replaced by a trivalent or tetravalent element other than silicon and aluminum, and the replacement rate does not exceed 80%. Here, the parameter "replacement rate" is dimensionless. The elements other than silicon and aluminum are selected from at least one of boron, tin, zirconium, and titanium. For example, when aluminum is replaced by the trivalent element boron, the replacement rate = 2X2O3 / (2X2O3 + 2Al2O3)×100% where X is the trivalent element, and when aluminum is replaced by the tetravalent element, the replacement rate = YO2 / (YO2 + 2Al2O3)×100%, where Y is the tetravalent element. When calculating the replacement rate, the molar numbers of the corresponding oxides are used. When replacing aluminum atoms with trivalent or tetravalent elements other than silicon and aluminum, a source of trivalent or tetravalent elements other than silicon and aluminum needs to be added to the mixture, preferably an oxide source of trivalent or tetravalent elements other than silicon and aluminum. As the above oxide source, preferably one selected from the group consisting of an oxide boron source, an oxidation tin source, an oxidation zirconium source, and an oxidation titanium source is selected. As the boron oxide source, specifically, at least one selected from the group consisting of boron oxide, borax, sodium metaborate, and boric acid can be cited. As the above oxidation tin source, specifically, at least one selected from the group consisting of tin tetrachloride, stannous chloride, alkyl tin, alkoxy tin, and organotin acid ester can be cited. As the oxidation zirconium source, specifically, one selected from the group consisting of zirconium salts (zirconium nitrate, zirconium sulfate), alkyl zirconium, alkoxy zirconium, and organo zirconate can be cited. As the oxidation titanium source, specifically, one or more selected from the group consisting of tetraalkyl titanates (such as tetramethyl titanate, tetraethyl titanate, tetrapropyl titanate, tetrabutyl titanate), TiCl4, hexafluorotitanic acid, titanium sulfate, and their hydrolysis products can be cited.

[0074] Molecular sieves NJU120-1 and NJU120-2 can be used in combination with other materials to obtain a molecular sieve composition.

[0075] The molecular sieves NJU120-1 and NJU120-2 or the molecular sieve composition can be used as an adsorbent, for example, to separate at least one component from a mixture of multiple components in the gas phase or liquid phase by contacting the mixture with the molecular sieves NJU120-1 and NJU120-2 or the molecular sieve composition to selectively adsorb this component.

[0076] The molecular sieves NJU120-1 and NJU120-2 or the molecular sieve composition can be used directly or after necessary treatments or conversions (such as ion exchange, etc.) conventional in the art for molecular sieves as a catalyst (or as a catalytically active component). For this purpose, according to one aspect of the present invention, for example, reactants can be subjected to a predetermined reaction in the presence of the catalyst to thereby obtain the target product.

[0077] In the present invention, in order to more clearly illustrate the present invention, examples are listed below. These examples have no limitation on the protection scope of this patent.

[0078] Example 1

[0079] Taking templating agent 4 as an example, the general synthesis process of the templating agent is described. 17.93 g of n-butylbis(1-adamantyl)phosphine and 200 ml of toluene were mixed in a 500 ml round-bottom flask. At room temperature, 14.25 g of methyl iodide was added dropwise to the mixture. The system was reacted at room temperature with stirring for one day. The reaction mixture was concentrated by rotary evaporation to remove the solvent to obtain a crude product, and the product (30.55 g, yield 95%) was obtained by recrystallization from methanol. The product was characterized by liquid nuclear magnetic resonance (D2O) and electrospray mass spectrometry and confirmed to be the target compound. The obtained product was dispersed in 400 ml of deionized water and subjected to column exchange through a pre-treated IRN-78 strong-base anion exchange resin (manufacturer: Thermo Fisher) to obtain an aqueous solution of templating agent 6. An appropriate amount of this solution was weighed and titrated with 0.1 mol / L hydrochloric acid solution using phenolphthalein as an indicator. The titration result confirmed that the exchange efficiency from iodide salt to hydroxide reached 97%.

[0080] Example 2

[0081] Prepare the gel for synthesizing molecular sieve according to the molar ratio of 0.5ROH:0.025Al2O3:SiO2:15H2O. The general steps are as follows: Weigh an appropriate amount of the template agent solution of Example 1 after exchange, add 0.03 mmol (0.007 g) of aluminum isopropoxide powder thereto, stir for about half an hour, then add 1.4 mmol (0.291 g) of tetraethyl orthosilicate, and stir at room temperature for about two hours until the tetraethyl orthosilicate is completely dissolved. Stir evenly, place the mixed gel under an infrared lamp or in an oven at 80 °C to remove the excess solvent. Transfer the finally obtained reaction gel to a 5 ml stainless steel autoclave with a polytetrafluoroethylene lining, react at 190 °C for 24 days under sealed conditions. Wash the product twice with water and twice with ethanol, and dry for later use. The product is directly used for X-ray powder diffraction phase identification and is confirmed to be NJU-120-1. Take an appropriate amount of the sample, calcine it in a muffle furnace at 600 °C in an air atmosphere for 2 hours to remove the template agent. Wash, centrifuge, and dry the product to obtain the NJU120-1 molecular sieve product.

[0082] Example 3

[0083] Prepare the gel for synthesizing molecular sieve according to the molar ratio of 0.5ROH:0.033Al2O3:SiO2:15H2O. The general steps are as follows: Weigh an appropriate amount of the template agent solution of Example 1 after exchange, add 0.04 mmol (0.009 g) of aluminum isopropoxide powder thereto, stir for about half an hour, then add 1.4 mmol (0.297 g) of tetraethyl orthosilicate, and stir at room temperature for about two hours until the tetraethyl orthosilicate is completely dissolved. Stir evenly, place the mixed gel under an infrared lamp or in an oven at 80 °C to remove the excess solvent. Transfer the finally obtained reaction gel to a 5 ml stainless steel autoclave with a polytetrafluoroethylene lining, react at 190 °C for 24 days under sealed conditions. Wash the product twice with water and twice with ethanol, and dry for later use. The product is directly used for X-ray powder diffraction phase identification and is confirmed to be NJU-120-1. Take an appropriate amount of the sample, calcine it in a muffle furnace at 600 °C in an air atmosphere for 2 hours to remove the template agent. Wash, centrifuge, and dry the product to obtain the NJU120-1 molecular sieve product.

[0084] Example 4

[0085] Prepare the gel for synthesizing molecular sieve according to the molar ratio of 0.5ROH:0.025Al2O3:0.3HF:SiO2:15H2O. The general steps are as follows: Weigh an appropriate amount of the template agent solution after exchange in Example 1, add 0.03 mmol (0.007 g) of aluminum isopropoxide powder thereto, stir for about half an hour, then add 1.4 mmol (0.291 g) of tetraethyl orthosilicate, and stir at room temperature for about two hours until the tetraethyl orthosilicate is completely dissolved. Then add the corresponding amount of hydrofluoric acid solution according to the above ratio, stir evenly, place the mixed gel under an infrared lamp or in an oven at 80 °C to remove the excess solvent. Transfer the finally obtained reaction gel to a 5-ml stainless steel autoclave with a polytetrafluoroethylene liner, react at 175 °C for 42 days under sealed conditions. Wash the product twice with water and twice with ethanol, and dry for later use. The product is directly used for X-ray powder diffraction phase identification and is confirmed to be NJU-120-1. Take an appropriate amount of the sample, calcine it in a muffle furnace at 600 °C in an air atmosphere for 2 hours to remove the template agent. Wash, centrifuge, and dry the product to obtain the NJU120-1 molecular sieve product.

[0086] Example 5

[0087] Prepare the gel for synthesizing molecular sieve according to the molar ratio of 0.5ROH:0.050Al2O3:SiO2:5H2O. The general steps are as follows: Weigh an appropriate amount of the template agent solution after exchange in Example 1, add 0.06 mmol (0.014 g) of aluminum isopropoxide powder thereto, stir for about half an hour, then add 1.4 mmol (0.297 g) of tetraethyl orthosilicate, and stir at room temperature for about two hours until the tetraethyl orthosilicate is completely dissolved. Stir evenly, place the mixed gel under an infrared lamp or in an oven at 80 °C to remove the excess solvent. Transfer the finally obtained reaction gel to a 5-ml stainless steel autoclave with a polytetrafluoroethylene liner, react at 175 °C for 42 days under sealed conditions. Wash the product twice with water and twice with ethanol, and dry for later use. The product is directly used for X-ray powder diffraction phase identification and is confirmed to be NJU-120-1. Take an appropriate amount of the sample, calcine it in a muffle furnace at 600 °C in an air atmosphere for 2 hours to remove the template agent. Wash, centrifuge, and dry the product to obtain the NJU120-2 molecular sieve product.

[0088] Example 6

[0089] Prepare the gel for synthesizing molecular sieve according to the ratio of 0.5ROH:0.033Al2O3:SiO2:8H2O. The general steps are as follows: Weigh an appropriate amount of the template agent solution of Example 1 after exchange, add 0.04 mmol (0.009 g) of aluminum isopropoxide powder thereto, stir for about half an hour, then add 1.4 mmol (0.297 g) of tetraethyl orthosilicate, and stir at room temperature for about two hours until the tetraethyl orthosilicate is completely dissolved. Stir evenly, place the mixed gel under an infrared lamp or in an oven at 80 °C to remove the excess solvent. Transfer the finally obtained reaction gel to a 5 ml stainless steel autoclave with a polytetrafluoroethylene liner, and react at 190 °C for 14 days under sealed conditions. The product is washed twice with water and twice with ethanol, and then dried for use. The product is directly used for X-ray powder diffraction phase identification and is confirmed to be NJU-120-2. Take an appropriate amount of the sample, calcine it in a muffle furnace at 600 °C in an air atmosphere for 2 hours to remove the template agent. The product is washed, centrifuged, and dried to obtain the NJU120-2 molecular sieve product.

[0090] The three-dimensional electron diffraction test (3DED) was carried out on the molecular sieves of Examples 2-6. The structure analysis results show that the NJU-120-1 molecular sieve structure has orthorhombic symmetry and belongs to the Imma space group, and the NJU-120-2 molecular sieve structure has monoclinic symmetry and belongs to the P21 / n space group. The crystallographic structure file (CIF file) obtained after cRED test is used for topological analysis. The topological analysis software is based on ToposPro 5.3.0.2, and the analysis process and method are based on the operation manual given on the official website of this software (see ToposPro official website: https: / / topospro.com / software / ). The analysis results show that the NJU120-1 molecular sieve framework structure has 14 topologically independent T atoms. The more specific topological characteristics of the NJU120-1 molecular sieve framework structure are as shown in the attached figure Figure 1 as shown. The NJU120-2 molecular sieve framework structure has 28 topologically independent T atoms. The more specific topological characteristics of the NJU120-2 molecular sieve framework structure are as shown in the attached figure Figure 2 as shown.

[0091] As mentioned above, it is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

Claims

1. Aluminosilicate molecular sieve with ultra-large pore structure, characterized in that: The schematic chemical composition of the molecular sieve in the synthesized state is: rROH: a(OH- or F-): xAl2O3: SiO2: wH2O, and the schematic chemical composition of the molecular sieve after calcination is: (HAlO2) x ·SiO2.

2. The aluminosilicate molecular sieve with ultra-large pore structure according to claim 1, characterized in that: The molecular sieve is NJU120-1. After calcination, the framework structure of NJU120-1 composed of T(Si, Al)O4 tetrahedrons has a three-dimensional pore system of 22×10×10 rings.

3. The aluminosilicate molecular sieve with ultra-large pore structure according to claim 2, characterized in that: The molecular sieve NJU120-1 has X-ray powder diffraction characteristics before and after calcination as shown in Table A1 and Table A2 below. Table A1 X-ray powder diffraction characteristics of NJU120-1 before calcination Table A2 X-ray powder diffraction characteristics of NJU120-1 after calcination 4. The aluminosilicate molecular sieve with ultra-large pore structure according to claim 2-3, characterized in that: The T (silicon, aluminum) atoms of the NJU120-1 have topological features as shown in the following figure.

5. The aluminosilicate molecular sieve with ultra-large pore structure according to claim 1, characterized in that: The molecular sieve is NJU120-2. After calcination, the framework structure of NJU120-2 composed of T(Si, Al)O4 tetrahedrons has a three-dimensional pore system of 22×12×10 rings.

6. The aluminosilicate molecular sieve with ultra-large pore structure according to claim 5, characterized in that: The NJU120-2 has X-ray powder diffraction characteristics before and after calcination as shown in Table A3 and Table A4 below. Table A3 X-ray powder diffraction characteristics of NJU120-2 before calcination Table A4 X-ray powder diffraction characteristics of NJU120-2 after calcination 7. The aluminosilicate molecular sieve with ultra-large pore structure according to claims 5-6, characterized in that: The T (silicon, aluminum) atoms of the NJU120-2 have topological features as shown in the following figure. Continued from the table 8. The method for synthesizing the aluminosilicate molecular sieve with ultra-large pore structure according to claims 1-7, characterized in that: The following steps are involved: S1, under stirring conditions, a silicon source, an aluminum source, an organic template, water, and an optional mineralizer (F - or OH - ) are mixed uniformly in proportion, and the obtained mixture forms a reaction gel, the chemical composition of the reaction gel is rROH:a(OH- or F-):xAl2O3:SiO2:wH2O, wherein R represents the positively charged group of the organic template; the corresponding value ranges of r, a, x and w are: r=0.1-5.0, a=0-5.0, x=0-1.0, w=1-100; the preferred value ranges of r, a, x and w are: r=0.1-2.0, a=0-2.0, x=0-0.5, w=1-30; S2, placing the reaction gel under an infrared lamp or in an oven, removing excess solvent, transferring the reaction gel to a stainless steel reactor, and reacting at a temperature of 80-240° C. for 1-60 days under sealed conditions for crystallization; S3, washing and drying the crystallized product, and then calcining it in an air atmosphere at 300-850° C. for 2-5 hours to remove the template.

9. The method for synthesizing the aluminosilicate molecular sieve with ultra-large pore structure according to claim 8, characterized in that: The organic template has a tetrahedral spatial configuration represented by the following general formula: Wherein, R1, R2, are phenyl, cyclohexyl or adamantane, R3, R4 are C 1-4 Alkyl (methyl, ethyl, propyl, butyl), cyclohexyl, or adamantane, X is P (phosphorus), N (nitrogen), R1, R2 are preferably adamantane, R3, R4 are preferably C 1-4 Alkyl, X is preferably phosphorus.

10. The method for synthesizing the aluminosilicate molecular sieve with ultra-large pore structure according to claim 9, characterized in that: The organic template is selected from any one or more of the following:

11. The method for synthesizing an aluminosilicate molecular sieve having a super large pore structure according to claim 8, characterized in that: The silicon source is selected from at least one of silicic acid, silica gel, silica sol, tetraalkyl silicate and water glass.

12. The method for synthesizing an aluminosilicate molecular sieve having a super large pore structure according to claim 8, characterized in that: The boron group element compound is selected from at least one of sodium aluminate, aluminum isopropoxide, aluminum sulfate hexadecahydrate, aluminum hydroxide or boric acid.

13. The method for synthesizing an aluminosilicate molecular sieve having a super large pore structure according to claim 8, characterized in that: No more than 80% of the aluminum atoms in the molecular sieve are replaced by at least one element other than silicon and aluminum.

14. The method for synthesizing an aluminosilicate molecular sieve having a super large pore structure according to claim 13, characterized in that: The non-silicon and non-aluminum element is at least one element selected from the group consisting of boron, tin, zirconium and titanium.

15. The method for synthesizing an aluminosilicate molecular sieve having a super large pore structure according to claim 8, characterized in that: In said S1, the mineralizer used is selected from the group consisting of - or OH - Ionic compounds.

16. The method for synthesizing an aluminosilicate molecular sieve having a super large pore structure according to claim 8, characterized in that: The mixture contains 0.01 ppm by weight to 10000 ppm by weight of seed crystals.

17. The method for synthesizing an aluminosilicate molecular sieve having a super large pore structure according to claim 8, characterized in that: The seed crystal comprises the molecular sieve according to any one of claims 1-7.

18. A molecular sieve composition, characterized in that: The invention comprises the molecular sieve according to any one of claims 1 to 7 or the molecular sieve synthesized according to the method according to any one of claims 8 to 17, and a binder.

19. The molecular sieve composition according to claim 18, characterized in that: The molecular sieve composition is used as an adsorbent or a catalyst.

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