Aluminosilicate molecular sieves having ultra-large pore structures, synthesis method therefor, and use thereof

Abstract

Provided are two aluminosilicate molecular sieves having ultra-large pore structures, designated NJU120-1 and NJU120-2. The schematic chemical composition of the as-synthesized state of the molecular sieves is: rROH:a(OH- or F-):xAl 2O 3:SiO 2:wH 2O, and the schematic chemical composition after calcination is: (HAlO 2) x·SiO 2. After calcination of NJU120-1, the framework structure composed of a T(Si, Al)O 4 tetrahedron thereof has a 22 × 10 × 10-membered cyclic three-dimensional pore channel system. After calcination of NJU120-2, the framework structure composed of a T(Si, Al)O 4 tetrahedron thereof has a 22 × 12 × 10-membered cyclic three-dimensional pore channel system. The molecular sieves are reasonably designed, are germanium-free, high-silicon or pure-silicon, fully connected ultra-large pore molecular sieve materials, and have very important practical application value in areas including catalysis, adsorptive separation, etc.

Description

Aluminosilicate molecular sieve with super-large pore structure, and synthesis method and use thereof TECHNICAL FIELD

[0001] The present application relates to the technical field of zeolite molecular sieves, and particularly relates to an aluminosilicate molecular sieve with a super-large pore structure, and a synthesis method and use thereof. BACKGROUND

[0002] Zeolite molecular sieves are a kind of inorganic crystal materials with regular microporous / mesoporous pore channel structures, are formed by bridging oxygen atoms between TO4 (T atoms can be silicon, aluminum, phosphorus, germanium and gallium, etc.) tetrahedrons as basic structural units to form a regular and ordered three-dimensional framework structure. Different connection modes between TO4 can construct a variety of zeolite materials with different topological configurations. Zeolite molecular sieves generally have one-dimensional or multi-dimensional pores, and the pore opening size ranges from an eight-membered ring (diameter about 0.4 nm) to a thirty-membered ring (diameter about 1.93 nm). The structural unit of the molecular sieve determines its long-range ordered porous structure, and at the same time endows the molecular sieve with excellent performance 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 the synthesis raw materials, so as to change the surface polarity and electric field, so as to achieve the best catalytic and adsorption separation effect. The hydrothermal synthesis method is the most common method for synthesizing molecular sieves, and generally only needs to mix a silicon source (silica sol, etc.), an aluminum source (inorganic aluminum salt, etc.), a base and water in a proper ratio, and then heat in a hydrothermal synthesis kettle for a certain time to synthesize molecular sieve crystals. Sometimes some organic amine templates need to be added to play a structure guiding role, but these templates are mostly low in price. 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 needs of industrial applications. A molecular sieve with a specific structure also needs to be further distinguished by X-ray powder diffraction (XRD), because different crystal structures make different molecular sieves have different pore structures, and different diffraction patterns are 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) and the like 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 super large pore molecular sieves according to the number of channels, corresponding to the window ring number of 8-membered ring or less, 10-membered ring or less, 12-membered ring or less and more than 12-membered ring. The super large pore zeolite molecular sieve with more than 12-membered ring is very difficult to crystallize, usually needs special organic structure directing agent and participation of germanium element, such as 30-membered ring ITQ-37 [J. Sun et. al., Nature, 2009, 458, 1154-1157], 28-membered ring ITQ-43 [J. Jiang et. al., Science, 2011, 333, 1131-1134] and 18-membered ring NUD-1 molecular sieve (CN104370296A) and the like. The germanium element is firstly expensive, and the hydrothermal stability of the molecular sieve framework containing germanium is poor, which limits the application range of the super large pore zeolite molecular sieve containing germanium.

[0004] Due to the good stability of zeolite molecular sieve materials in silicoaluminate form, the chemical microenvironment in the channel is easy to manipulate, and it is widely used in petroleum chemical industry, fine chemical industry, energy conversion and storage, and biological medicine. However, the number of silicoaluminate molecular sieve materials with super large pore and stable framework structure is limited, such as 16-membered ring ZEO-1 molecular sieve (Lin et. al., Science, 2021, 374, 1605-1608.), 16-membered ring ZEO-3 molecular sieve (Li et. al., Science, 2023, 379, 283-287) and recently reported 20-membered ring ZEO-5 molecular sieve (Gao et. al., Nature, 2024, 628, 99-103.). ZEO-3 and ZEO-5 are both pure silicon framework, and are not directly synthesized by hydrothermal synthesis, but are obtained by post-processing. Super large pore silicoaluminate molecular sieves have very important practical value for processing chemical processes containing macromolecules. SUMMARY

[0005] The present application provides an aluminosilicate molecular sieve with a super large pore structure, as well as a synthesis method and application thereof. The aluminosilicate molecular sieve with a super large pore structure is a new type of super large pore molecular sieve material without germanium and with high silicon or pure silicon, which 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 the molecular sieve structure family.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0007] The aluminosilicate molecular sieve with a super large pore structure has a synthetic chemical composition of rROH:a(OH- or F-):xAl2O3:SiO2:wH2O, and a calcined chemical composition of (HAlO2)x • SiO2.

[0008] Preferably, the molecular sieve is NJU120-1, which, after calcination, has a three-dimensional pore system of 22x10x10-membered rings in the framework structure of T(Si, Al)O4 tetrahedra.

[0009] Preferably, the molecular sieve is NJU120-2, which, after calcination, has a three-dimensional pore system of 22x12x10-membered rings in the framework structure of T(Si, Al)O4 tetrahedra.

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

[0011] S1, under stirring, uniformly mixing a silicon source, an aluminum source, an organic template agent, and water, and optionally a mineralizer (F - or OH - ) in proportion to obtain a mixture, which forms a reaction gel, the chemical composition of the reaction gel being rROH:a(OH- or F-):xAl2O3:SiO2:wH2O, wherein R represents a positive charge group of the organic template agent; the value intervals of corresponding r, a, x, and w are respectively: r=0.1-5.0, a=0-5.0, x=0-1.0, w=1-100; the preferred value intervals of r, a, x, and w are respectively: r=0.1-2.0, a=0-2.0, x=0-0.5, w=1-30;

[0012] S2, placing the reaction gel under an infrared lamp or in an oven, after removing the excess solvent, transferring the reaction gel to a stainless steel reaction kettle, and performing crystallization under a sealed condition at a temperature of 80-240℃ for 1-60 days;

[0013] S3, after washing and drying the product after crystallization, calcining at 300-850℃ in an air atmosphere 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] 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, R 3、 R4 is preferably C 1-4 alkyl, and X is preferably phosphorus.

[0016] Preferably, the organic template is selected from any one or more of the following:

[0017] Preferably, the silicon source is selected from at least one of silicic acid, silica gel, silica sol, tetraalkyl orthosilicate and water glass.

[0018] Preferably, the boron group compound is selected from at least one of sodium metaaluminate, aluminum isopropoxide, aluminum sulfate hexadecahydrate, aluminum hydroxide or boric acid.

[0019] Preferably, no more than 80% of the aluminum atoms in the molecular sieve are substituted with at least one element other than silicon and aluminum.

[0020] Preferably, the element other than silicon and aluminum is selected from at least one of the elements consisting of boron, tin, zirconium and titanium.

[0021] Preferably, in the S1, the mineralizer used is selected from a compound containing F - or OH - ions.

[0022] Preferably, the mixture contains 0.01 ppm by weight to 10000 ppm by weight of seed crystals.

[0023] Preferably, the seed crystals comprise the molecular sieve of any one of the present invention.

[0024] A molecular sieve composition comprising the molecular sieve of the present invention, and a binder.

[0025] Preferably, the use of the molecular sieve composition as an adsorbent or catalyst.

[0026] The present invention has the following beneficial effects compared to the prior art:

[0027] NJU120-1 molecular sieve has a brand new 22x10x10 three-dimensional pore system, and NJU120-2 molecular sieve has a brand new 22x12x10 three-dimensional pore system. 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 DRAWINGS

[0028] Figure 1 is the more specific topological features of the framework structure of the NJU120-1 molecular sieve of the present invention;

[0029] Figure 2 is the more specific topological features of the framework structure of the NJU120-2 molecular sieve of the present invention;

[0030] Figure 3 is an X-ray powder diffraction pattern (Cu target Kα ray) of the NJU120-1 molecular sieve of the present application before and after removal of the template at a high temperature of 600°C;

[0031] Figure 4 is a schematic diagram of the pore channels of the crystal structure of the NJU120-1 molecular sieve of the present application in different directions;

[0032] Figure 5 is a scanning electron microscope (SEM) image of the NJU120-1 molecular sieve of the present application;

[0033] Figure 6 is an X-ray powder diffraction pattern (Cu target Kα ray) of the NJU120-2 molecular sieve of the present application before and after removal of the template at a high temperature of 600°C;

[0034] Figure 7 is a schematic diagram of the pore channels of the crystal structure of the NJU120-2 molecular sieve of the present application in different directions;

[0035] Figure 8 is a scanning electron microscope (SEM) image of the NJU120-2 molecular sieve of the present application. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments.

[0037] Referring to Figures 1-8, the aluminosilicate molecular sieve with a super-large pore structure generally further contains organic matter (such as an organic template) and water in the composition after being synthesized. Therefore, the schematic chemical composition of the as-synthesized molecular sieve is: rROH:a(OH- or F-):xAl203:SiO2:wH2O, wherein R represents a positive charge group of the organic template. The schematic chemical composition of the calcined molecular sieve is: (HAlO2) x ·SiO 2， wherein 0≤x≤1, preferably x=0-0.5, and more preferably x=0-0.2;

[0038] Example 1

[0039] The molecular sieve is NJU120-1, and the T (silicon, aluminum) atoms have the topological characteristics shown in Figure 1. The calcined NJU120-1 has a three-dimensional pore channel system with 22×10×10-membered rings in the framework structure composed of T (Si, Al)O4 tetrahedra.

[0040] The as-synthesized and calcined NJU120-1 molecular sieves have the X-ray powder diffraction characteristics shown in Table A1 and Table A2 below:

[0041] Table A1 X-ray powder diffraction characteristics of the as-synthesized NJU120-1

[0042] Table A2 X-ray powder diffraction characteristics of NJU120-1 after calcination

[0043] In the above data, w, mw, m, s, vs represent the intensity of diffraction peak, w is weak, mw is medium-weak, m is medium, s is strong, and vs is very strong, which is known by 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.

[0044] Example Two

[0045] The molecular sieve is NJU120-2, and T (silicon, aluminum) atoms have topological characteristics as shown in Figure 2. NJU120-2, after calcination, has a three-dimensional pore system with 22x12x10-membered rings in the framework structure composed of T (Si, Al) O4 tetrahedra;

[0046] NJU120-2 before and after calcination has the X-ray powder diffraction characteristics shown in Table A3 and Table A4 as follows:

[0047] Table A3 X-ray powder diffraction characteristics of NJU120-2 before calcination

[0048] Table A4 X-ray powder diffraction characteristics of NJU120-2 after calcination

[0049] In the above data, w, mw, m, s, vs represent the intensity of diffraction peak, w is weak, mw is medium-weak, m is medium, s is strong, and vs is very strong, which is known by 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] The present application also provides a method for synthesizing an aluminosilicate molecular sieve with a super-large pore structure, comprising the following steps:

[0051] S1, under stirring conditions, a silicon source, an aluminum source, an organic template agent, water, and optionally a mineralizer (F - or OH -) are mixed in proportion to form a reaction gel, the chemical composition of the reaction gel being rROH : a(OH- or F-) : xAl203 : Si02 : wH20, wherein R represents a positively charged group of an organic template agent; the value ranges of corresponding r, a, x and w are respectively: 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 respectively: r = 0.1-2.0, a = 0-2.0, x = 0-0.5, w = 1-30;

[0052] 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 mentioned. These silicon sources can be used singly or in combination in the desired proportions;

[0053] As the mineralizer, either F"ions or OH"ions can be used, 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 can be mentioned.

[0054] 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 salt, kaolin and montmorillonite can be mentioned.

[0055] S2, the reaction gel is placed under an infrared lamp or in an oven, and after the excess solvent is removed, the reaction gel is transferred to a stainless steel autoclave, and is reacted at a temperature of 80-240°C, preferably 120-220°C, under sealed conditions for 1-60 days, preferably 2-45 days, more preferably 3 to 30 days, to perform crystallization. After the crystallization is completed, the molecular sieve can be separated from the obtained reaction mixture as a product by any separation method conventionally known in the art, and thus the molecular sieve NJU120-1 and NJU120-2, also referred to as the as-synthesized form of the molecular sieve NJU120-1 and NJU120-2, are obtained. As the separation method, for example, a method of filtering, washing and drying the obtained reaction mixture can be mentioned. The filtering, washing and drying can be performed in any manner conventionally known in the art.

[0056] S3, the crystallized product is washed, dried and calcined at 300-850°C in air for 2-5 hours to remove the template and possibly water and the like, thereby obtaining the calcined molecular sieve, also referred to as the calcined form of the molecular sieve NJU120-1 and NJU120-2. The molecular sieve, as synthesized, can also further contain organic materials (such as the organic template) and water in its composition. Therefore, the molecular sieve NJU120-1 and NJU120-2 can also have a schematic chemical composition as shown in the formula rROH:a(OH"or F"):xAl2O3:SiO2:wH2O, wherein R represents the positively charged group of the organic template. Here, by calcining the molecular sieve having the schematic chemical composition of "rROH:a(OH"or F"):xAl2O3:SiO2:wH2O" so as to remove any organic template and water and the like from its pores, the molecular sieve having the schematic chemical composition of "(HAlO2) x :SiO2" can be obtained. The calcination can be carried out in any manner known in the art, such as a calcination temperature of generally from 300 to 850, preferably 400 to 600, and a calcination time of generally 1 hour to 10 hours, preferably from 3 hours to 6 hours. The calcination is generally carried out in an oxygen-containing atmosphere, such as an air or oxygen atmosphere.

[0057] In the schematic chemical composition rROH:a(OH"or F"):xAl2O3:SiO2:wH2O, wherein R represents the positively charged group of the organic template, the organic template has a tetrahedral spatial configuration represented by the following general formula:

[0058] 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, and X is preferably phosphorus.

[0059] The organic template is selected from any one or more of the following:

[0060] Preferably These organic templates can be used individually or in combination in the desired proportions.

[0061] In the molecular sieves NJU120-1 and NJU120-2, the framework Al can be partially replaced by non-silicon and non-aluminum trivalent or tetravalent elements, and the replacement rate is not more than 80%. In this case, the parameter "replacement rate" is dimensionless. The non-silicon and non-aluminum elements are selected from at least one of boron, tin, zirconium and titanium. For example, when the aluminum is replaced by the trivalent element boron, the replacement rate = 2X2O3 / (2X2O3+2Al2O3) x 100%, wherein X is a trivalent element, and when the aluminum is replaced by the tetravalent element, the replacement rate = YO2 / (YO2+2Al2O3) x 100%, wherein Y is a tetravalent element. In the calculation of the replacement rate, the number of moles of the corresponding oxide is used. When the trivalent or tetravalent non-silicon and non-aluminum element is used to replace the aluminum atom, a source of the non-silicon and non-aluminum trivalent or tetravalent element, preferably a source of the oxide of the non-silicon and non-aluminum trivalent or tetravalent element, is added to the mixture. As the oxide source, one selected from the group consisting of a boron oxide source, a tin oxide source, a zirconium oxide source and a titanium oxide source is preferred. As the boron oxide source, for example, at least one selected from the group consisting of boron oxide, borax, sodium metaborate and boric acid can be specifically mentioned. As the tin oxide source, for example, at least one selected from the group consisting of tin tetrachloride, stannous chloride, alkyl tin, alkoxy tin and organotin acid ester can be specifically mentioned. As the zirconium oxide source, for example, one selected from the group consisting of zirconium salts (zirconium nitrate, zirconium sulfate), alkyl zirconium, alkoxy zirconium, organozirconium acid ester can be specifically mentioned. As the titanium oxide source, for example, one or more selected from the group consisting of titanium acid tetraalkyl ester (such as titanium acid tetramethyl ester, titanium acid tetraethyl ester, titanium acid tetrapropyl ester, titanium acid tetrabutyl ester), TiCl4, hexafluorotitanic acid, titanium sulfate and their hydrolysis products can be specifically mentioned.

[0062] The molecular sieves NJU120-1 and NJU120-2 can be used in combination with other materials, thereby obtaining a molecular sieve composition.

[0063] 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 components in the gas phase or in the liquid phase by contacting the mixture with the molecular sieves NJU120-1 and NJU120-2 or the molecular sieve composition, selectively adsorbing the component.

[0064] The molecular sieves NJU120-1 and NJU120-2 or the molecular sieve composition can be used as a catalyst (or as a catalytically active component) directly or after necessary treatment or conversion (such as ion exchange, etc.) for molecular sieves in the art. For this purpose, according to one aspect of the present application, for example, the reactants can be subjected to a predetermined reaction in the presence of the catalyst, and thereby the target product can be obtained.

[0065] In the present application, in order to more clearly illustrate the present application, some examples are listed. These examples have no any limitation on the protection scope of the present patent.

[0066] Example 1

[0067] The general synthesis procedure of the template agent is illustrated by taking template agent 4 as an example. 17.93 g of n-butyl bis(1-adamantyl)phosphine and 200 ml of toluene were mixed in a 500 ml round bottom flask. At room temperature, iodomethane 14.25 g was added dropwise into the mixture. The system was allowed to react at room temperature for one day under stirring. The reaction mixture was subjected to rotary evaporation to remove the solvent to obtain the crude product, which was recrystallized from methanol to obtain the product 30.55 g with a yield of 95%. 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 by a pre-treated IRN-78 strong base anion exchange resin (manufacturer: Thermo Fisher). The exchanged aqueous solution of template agent 6 was obtained. An appropriate amount of the solution was weighed, and titrated with 0.1 mol / L hydrochloric acid solution, with phenothalin as the indicator. The titration structure confirmed that the exchange efficiency of iodine salt to hydroxyl group reached 97%.

[0068] Example 2

[0069] The gel for molecular sieve synthesis was prepared according to the molar ratio of 0.5 ROH:0.025 Al2O3:SiO2:15 H2O. The general procedure was as follows: an appropriate amount of the exchanged template agent solution of Example 1 was weighed, 0.03 mmol (0.007 g) of aluminum isopropoxide powder was added thereto, and stirred for about half an hour. Then, 1.4 mmol (0.291 g) of tetraethyl orthosilicate was added, and stirred at room temperature for about two hours to completely dissolve the tetraethyl orthosilicate. The mixed gel was placed under an infrared lamp or in an oven at 80°C to remove the excess solvent. The finally obtained reaction gel was transferred to a 5 ml stainless steel autoclave with a polytetrafluoroethylene liner, and reacted at 190°C for 24 days under a sealed condition. The product was washed with water twice and ethanol twice, and dried for use. The product was directly used for X-ray powder diffraction phase identification, and confirmed to be NJU-120-1. An appropriate amount of sample was taken, calcined at 600°C in an air atmosphere for 2 hours in a muffle furnace to remove the template agent, and the product was washed with water, centrifuged, and dried to obtain the NJU 120-1 molecular sieve product.

[0070] Example 3

[0071] A gel for the synthesis of molecular sieve was prepared in a molar ratio of 0.5 ROH:0.033 Al203:Si02:15 H20. The general procedure was as follows: an appropriate amount of the template solution of Example 1 after ion exchange was weighed, 0.04 mmol (0.009 g) of aluminum isopropoxide powder was added thereto, stirring was carried out for about half an hour, 1.4 mmol (0.297 g) of tetraethyl orthosilicate was added, stirring was carried out at room temperature for about two hours until the tetraethyl orthosilicate was completely dissolved, the mixed gel was placed under an infrared lamp or in an oven at 80°C to remove the excess solvent. The finally obtained reaction gel was transferred into a 5 ml stainless steel autoclave with a polytetrafluoroethylene liner, and was reacted at 190°C for 24 days under sealed conditions, the product was washed with water twice, washed with ethanol twice, and was dried to be used. The product was directly used for phase identification by X-ray powder diffraction, and was confirmed to be NJU-120-1. An appropriate amount of sample was calcined at 600°C for 2 hours in a muffle furnace in an air atmosphere to remove the template, the product was washed with water, centrifuged, and dried to obtain the NJU 120-1 molecular sieve product.

[0072] Example 4

[0073] A gel for the synthesis of molecular sieve was prepared in a molar ratio of 0.5 ROH:0.025 Al203:0.3 HF:Si02:15 H20. The general procedure was as follows: an appropriate amount of the template solution of Example 1 after ion exchange was weighed, 0.03 mmol (0.007 g) of aluminum isopropoxide powder was added thereto, stirring was carried out for about half an hour, 1.4 mmol (0.291 g) of tetraethyl orthosilicate was added, stirring was carried out at room temperature for about two hours until the tetraethyl orthosilicate was completely dissolved, then the corresponding amount of hydrofluoric acid solution was added in the above ratio, and stirring was carried out uniformly. The mixed gel was placed under an infrared lamp or in an oven at 80°C to remove the excess solvent. The finally obtained reaction gel was transferred into a 5 ml stainless steel autoclave with a polytetrafluoroethylene liner, and was reacted at 175°C for 42 days under sealed conditions, the product was washed with water twice, washed with ethanol twice, and was dried to be used. The product was directly used for phase identification by X-ray powder diffraction, and was confirmed to be NJU-120-1. An appropriate amount of sample was calcined at 600°C for 2 hours in a muffle furnace in an air atmosphere to remove the template, the product was washed with water, centrifuged, and dried to obtain the NJU 120-1 molecular sieve product.

[0074] Example 5

[0075] A gel for zeolite synthesis was prepared in a molar ratio of 0.5 ROH:0.050 Al203:Si02:5 H20. The general procedure was as follows: an appropriate amount of the template solution of Example 1 after ion exchange was weighed, 0.06 mmol (0.014 g) of aluminum isopropoxide powder was added thereto, stirring was performed for about half an hour, 1.4 mmol (0.297 g) of tetraethyl orthosilicate was added, stirring was performed at room temperature for about two hours until the tetraethyl orthosilicate was completely dissolved, the mixed gel was stirred uniformly, and the mixed gel was placed in an infrared lamp or an oven at 80°C to remove the excess solvent. The finally obtained reaction gel was transferred into a 5 ml stainless steel autoclave with a polytetrafluoroethylene liner, and was reacted at 175°C for 42 days under a sealed condition, the product was washed with water twice and with ethanol twice, and was dried to be used. The product was directly used for phase identification by X-ray powder diffraction, and was confirmed to be NJU-120-1. An appropriate amount of sample was calcined at 600°C for 2 hours in an air atmosphere in a muffle furnace to remove the template, the product was washed with water, centrifuged, and dried to obtain the NJU 120-2 zeolite product.

[0076] Example 6

[0077] A gel for zeolite synthesis was prepared in a molar ratio of 0.5 ROH:0.050 Al203:Si02:5 H20. The general procedure was as follows: an appropriate amount of the template solution of Example 1 after ion exchange was weighed, 0.06 mmol (0.014 g) of aluminum isopropoxide powder was added thereto, stirring was performed for about half an hour, 1.4 mmol (0.297 g) of tetraethyl orthosilicate was added, stirring was performed at room temperature for about two hours until the tetraethyl orthosilicate was completely dissolved, the mixed gel was stirred uniformly, and the mixed gel was placed in an infrared lamp or an oven at 80°C to remove the excess solvent. The finally obtained reaction gel was transferred into a 5 ml stainless steel autoclave with a polytetrafluoroethylene liner, and was reacted at 175°C for 42 days under a sealed condition, the product was washed with water twice and with ethanol twice, and was dried to be used. The product was directly used for phase identification by X-ray powder diffraction, and was confirmed to be NJU-120-1. An appropriate amount of sample was calcined at 600°C for 2 hours in an air atmosphere in a muffle furnace to remove the template, the product was washed with water, centrifuged, and dried to obtain the NJU 120-2 zeolite product.

[0078] The three-dimensional electron diffraction test (3DED) was performed on the molecular sieves of Examples 2-6, and the structure analysis results showed that the structure of NJU-120-1 molecular sieve had orthorhombic symmetry, and belonged to Imma space group, and the structure of NJU-120-2 molecular sieve had monoclinic symmetry, and belonged to P21 / n space group. The crystallographic structure file (CIF file) obtained after cRED test was used for topological analysis. The topological analysis software was based on ToposPro 5.3.0.2, and the analysis process and method were based on the operation manual given on the official website of the software (see ToposPro official website: https: / / topospro.com / software / ). The analysis results showed that the framework structure of NJU120-1 molecular sieve had 14 topologically independent T atoms, and the more specific topological characteristics of the framework structure of NJU120-1 molecular sieve were shown in FIG. 1. The framework structure of NJU120-2 molecular sieve had 28 topologically independent T atoms, and the more specific topological characteristics of the framework structure of NJU120-2 molecular sieve were shown in FIG. 2.

[0079] The above merely illustrates the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can make equivalent replacements or changes to the technical solutions and the inventive concept of the present application within the technical scope disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

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

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

3. The aluminosilicate molecular sieve with an ultra-large pore structure according to claim 2, characterized in that, The molecular sieve NJU120-1 exhibits X-ray powder diffraction characteristics before and after calcination, as shown in Tables A1 and 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 claims 2-3, characterized in that, The NJU120-1 has T (silicon, aluminum) atoms with the topological characteristics shown in the figure below.

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

6. The aluminosilicate molecular sieve with an ultra-large pore structure according to claim 5, characterized in that, The NJU120-2 before and after calcination exhibits the X-ray powder diffraction characteristics shown in Tables A3 and 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 NJU120-2 has T (silicon, aluminum) atoms with the topological characteristics shown in the figure below. (Continued from the table above) 8. The method for synthesizing aluminosilicate molecular sieves with ultra-large pore structures according to claims 1-7, characterized in that, Includes the following steps: S1, under stirring conditions, a silicon source, an aluminum source, an organic template agent, water, and an optional mineralizer (F) are added. - or OH - The mixture is mixed evenly in a certain proportion to form a reactive gel. The chemical composition of the reactive gel is rROH:a(OH- or F-):xAl2O3:SiO2:wH2O, where R represents the positively charged group of the organic template agent; 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, place the reaction gel under an infrared lamp or in an oven to remove excess solvent, then transfer the reaction gel to a stainless steel reactor and crystallize it under sealed conditions at a temperature of 80-240℃ for 1-60 days. S3. After washing and drying the crystallized product, calcine it in air at 300-850℃ for 2-5 hours to remove the template agent.

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

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

11. The method for synthesizing aluminosilicate molecular sieves with ultra-large pore structures 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 aluminosilicate molecular sieves with ultra-large pore structures 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 hexadecoxide, aluminum hydroxide, or boric acid.

13. The method for synthesizing aluminosilicate molecular sieves with ultra-large pore structures 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 non-silicon and non-aluminum element.

14. The method for synthesizing aluminosilicate molecular sieves with ultra-large pore structures according to claim 13, characterized in that, The non-silicon and non-aluminum elements are selected from at least one of the elements composed of boron, tin, zirconium, and titanium.

15. The method for synthesizing aluminosilicate molecular sieves with ultra-large pore structures according to claim 8, characterized in that, In S1, the mineralizing agent used is selected from those containing F. - or OH - Compounds containing ions.

16. The method for synthesizing aluminosilicate molecular sieves with ultra-large pore structures according to claim 8, characterized in that, The mixture contains seed crystals ranging from 0.01 ppm to 10,000 ppm by weight.

17. The method for synthesizing aluminosilicate molecular sieves with ultra-large pore structures according to claim 8, characterized in that, The seed crystal comprises a molecular sieve according to any one of claims 1-7.

18. A molecular sieve composition, characterized in that, It comprises a molecular sieve according to any one of claims 1-7 or a molecular sieve synthesized by the method according to any one of claims 8-17, 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 catalyst.

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