WO2024244118A1 - New silicate zeolite molecular sieve zmq-1 and use - Google Patents

Abstract

A silicate zeolite molecular sieve ZMQ-1, a preparation method and the use. The non-aqueous chemical composition of a silicate zeolite molecular sieve precursor is SiO₂·1/xXO_1.5·mMO_0.5·qQ, wherein X is a framework trivalent element, the Si/X molar ratio x is ≥5, M is a framework-balanced cation, the M/Si molar ratio m satisfies 0≤m≤1, Q is a diquaternary ammonium or diquaternary phosphorus organic-structure-directing agent, and the Q/Si molar ratio q is ≥0.01. The non-aqueous chemical composition of a silicate zeolite molecular sieve is SiO₂·1/xXO_1.5·mMO_0.5, wherein X is a framework trivalent element, the Si/X molar ratio x is ≥5, M is a framework-balanced cation, and the M/Si molar ratio m satisfies 0≤m≤1. The molecular sieve can be further applied to the process of energy storage, sensing, loading, adsorption, separation or catalysis in view of the new topological structure, unique pore channel system, and high heat and hydrothermal stability thereof; and may show unique performance.

Description

A new type of silicate zeolite molecular sieve ZMQ-1 and its application Technical Field

The invention relates to a molecular sieve, in particular to a novel silicate zeolite molecular sieve ZMQ-1, and a preparation method and application thereof.

Background Art

Zeolite molecular sieve (hereinafter referred to as molecular sieve) is a very important type of inorganic microporous material. For half a century, molecular sieve has been widely used in oil processing, petrochemical industry and environmental chemical industry as catalysis, adsorption separation and ion exchange materials. According to the number of pore rings, molecular sieve materials can be divided into small pore, medium pore, large pore and ultra-large pore molecular sieves, corresponding to the window ring numbers of 8-membered rings and below, 10-membered rings and below, 12-membered rings and below and greater than 13-membered rings and above. So far, there are 260 types of molecular sieve structures recognized and accepted by the International Molecular Sieve Association (official website: https://asia.iza-structure.org/IZA-SC/ftc_table.php), each structure is represented by three capital letters, but there are less than 20 molecular sieves that have been truly industrialized, such as A-type, X-type and Y-type, mordenite, ZSM-5, ZSM-11, MCM-22, L-type, β-type, erionite, RHO, CHA, AEL type and TS-1, as well as SAPO-34, SAPO-11, SAPO-31, etc. In view of this, the development of molecular sieve materials with new structures and new properties has always been an important research direction in this field, which will effectively expand the application scope of molecular sieves and meet the growing needs of related industrial processes.

At present, the synthetic exploration method for new molecular sieves is still mainly based on trial and error or empirical method. The disadvantages of this method are that it is time-consuming, labor-intensive and not easy to obtain the desired target product. In addition, a large amount of waste will be generated in the process, which is a non-green and environmentally friendly molecular sieve synthesis method. In the 1960s, researchers introduced organic species into the molecular sieve synthesis process, and many new structures of high-silicon molecular sieves were synthesized. For example, tetraethylammonium, tetrapropylammonium and tetrabutylammonium cations were used as organic additives to successfully synthesize β, ZSM-5 and ZSM-11 molecular sieves. These organic species are usually used with alkali metal cations, and because they have a filling effect on the molecular sieve pores, they were initially called "template agents". However, with the in-depth study of the molecular sieve synthesis mechanism, it was found that many organic species do not have a strict matching relationship with the molecular sieve pore size or structure, and in many cases, one organic species can synthesize a variety of different molecular sieve structures. Therefore, the researchers named it "organic structure directing agent" (OSDAs, Organic Structure Directing Agents), which is also a definition generally recognized in the current field of molecular sieve synthesis. It The effect they produce is called "structure-directed effect" (ME Davis and RF Lobo, Chem. Mater., 1992, 4, 756-768). The proposal of "structure-directed effect" provides methodological guidance for the synthesis of molecular sieves, making the synthesis process more purposeful.

According to the different types of organic cations, organic structure-directing agents can be divided into quaternary ammonium cations, imidazolyl cations, quaternary phosphonium cations, sulfonium cations, proton sponges, metal complexes and neutral amines, among which quaternary ammonium and quaternary phosphonium cations are the most mature and widely used. Compared with quaternary ammonium cations, quaternary phosphonium cations have the following advantages: (1) the phosphorus atom is larger than the nitrogen atom, so it is easier to connect larger substituent groups; (2) quaternary phosphonium cations have higher thermal stability and can exist stably in an alkaline system at 190°C, while most quaternary ammonium cations will decompose and lose their structure-directing agent function. Therefore, in recent years, phosphorus-containing organic structure-directing agents have been widely used and developed, and several new structure molecular sieves have been synthesized (CN114538466A and CN115611293A), showing great potential in the development of new structure molecular sieves, which deserve further exploration and research.

In addition, the introduction of other inorganic species can also provide additional structural guidance. They can jointly guide the formation of molecular sieves with specific structures. Molecular sieves are microporous structural materials formed by alternating connection of TO ₄ tetrahedrons. Other elements, such as B, Al, Be, Mg, Ga, Ge, Zn and Co, can enter the molecular sieve framework by isomorphous substitution. The introduction of heteroatoms will also produce some unique chemical and physical properties, such as catalytic performance, selective adsorption or magnetic properties. In addition, heteroatoms will significantly affect the formation process of molecular sieves. For example, Ge, B, Ga, Zn and Be are conducive to the formation of specific structural units (such as 4-membered rings, 3-membered rings, double 4-membered rings, double 3-membered rings and spiral 5-membered rings, etc.), because their suitable TO bonds and TOT bond angles can stabilize these structural units.

In recent years, dozens of new structure molecular sieves have been synthesized based on the strategy of organic structure directing agent design and heteroatom introduction. The Avelino Corma research group in Spain has developed a variety of new molecular sieves named ITQ-n (Moliner et al, Angew. Chem. Int. Ed. 2013, 52, 13880-13889 and Li et al, Chem. Soc. Rev., 2015, 44, 7112-7127). The pore sizes of these molecular sieves range from small pores to ultra-large pores, greatly expanding the types of molecular sieve structures. However, most of these new structure molecular sieves contain germanium. After removing the organic structure directing agent and exposing it to air, the framework germanium will hydrolyze, eventually leading to the collapse of the framework, which greatly limits its practical application. The research group of Sukbong Hong in South Korea found that organic cations, The weak interaction between organic cations and aluminum species can also lead to the formation of molecular sieves with specific structures. They fixed the type of organic cations and introduced two inorganic cations (Na ⁺ and Cs ⁺ ) to form a mismatch in the charge density of the synthetic system, synthesizing a structurally stable macroporous SBT aluminosilicate molecular sieve, solving the problem of structural collapse after the organic structure directing agent of the molecular sieve was removed (Lee et al., 2021, Science 373, 104–107 and Lee et al., J. Am. Chem. Soc. 2022, 144, 18700-18709). However, this method involves many modulation factors, and the target molecular sieve can only be obtained within a narrow gel ratio range, which will affect the repeatability of the synthesis results to a certain extent. In addition, the synthesized molecular sieve has a low silicon-aluminum ratio, that is, a high aluminum content, which reduces its hydrothermal stability.

In summary, although zeolite molecular sieves or molecular sieve materials with various topological structures have been obtained, in the face of the growing new demands in the adsorption separation and catalytic conversion processes, in order to address the current problems of unstable structure and limited types of zeolite molecular sieves, it is urgent to develop new zeolite molecular sieve materials with diversified topologies and pore structures that are thermally and hydrothermally stable.

Summary of the invention

The present invention aims to provide a novel silicate zeolite molecular sieve (ZMQ-1), a preparation method and application thereof.

A silicate zeolite molecular sieve precursor has an anhydrous chemical composition of SiO ₂ ·1/xXO _1.5 ·mMO _0.5 ·qQ, wherein X is a framework trivalent element, Si/X molar ratio x≥5, M is a framework balancing cation, M/Si molar ratio 0≤m≤1, Q is a diquaternary ammonium or diquaternary phosphorus organic structure directing agent, and Q/Si molar ratio q≥0.01.

The X-ray diffraction characteristics of the silicate zeolite molecular sieve precursor powder are as follows:

In the data of this application form, the relative intensity of diffraction peaks is defined as shown in the following table.

A novel silicate zeolite molecular sieve has an anhydrous chemical composition of SiO ₂ ·1/xXO _1.5 ·mMO _0.5 , wherein X is a framework trivalent element, Si/X molar ratio x≥5, M is a framework balanced cation, and M/Si molar ratio 0≤m≤1.

The novel silicate zeolite molecular sieve contains a three-dimensional pore system consisting of 28×10×10 rings, wherein the size of the 28-membered ring is The size of the 10-membered ring is

The silicate molecular sieve is a novel topological structure of ultra-large pore molecular sieve, the largest pore of which is composed of 28-membered rings and has a size of It exceeds the micropore range defined by the International Organization for Standardization (less than 2nm). More importantly, the ZMQ-1 molecular sieve can be adjusted within the composition range of low silicon, high silicon or pure silicon.

The novel silicate zeolite molecular sieve has the powder X-ray diffraction characteristics shown in the following table:

The novel silicate zeolite molecular sieve is obtained by calcining the novel silicate zeolite molecular sieve precursor.

The framework trivalent element X is selected from at least one of boron, aluminum, gallium, indium, iron and chromium; the framework balanced cation M is selected from at least one of hydrogen ion, ammonium ion, lithium ion, sodium ion, potassium ion, rubidium ion and cesium ion; the silicon in the molecular sieve contains a non-silicon tetravalent framework element (Y) whose mass is greater than or equal to 0 and less than or equal to 10w%, wherein Y is selected from at least one of germanium, tin, titanium, zirconium and hafnium.

A method for preparing the novel silicate zeolite molecular sieve:

A framework balancing cationic compound, a silicon source, a framework trivalent element X source, an organic structure directing agent and water are mixed to obtain a synthetic gel; the synthetic gel is then aged and hydrothermally crystallized, and the crystallized product is calcined to remove the organic structure directing agent; wherein the molar ratio of the synthetic gel after aging is SiO ₂ :mM ₂ O:xX ₂ O ₃ :qQ(OH) ₂ :hH ₂ O, wherein M is a framework balancing cation, X is a framework trivalent element, and Q is a cationic group of the organic structure directing agent, and the value ranges of m, x, q and h are: m=0-1, x=0-0.5, q=0.1-1, and h=3-100;

The organic structure directing agent has the following configuration:

Wherein, Q may be the same or different and selected from nitrogen or phosphorus, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different and selected from cyclohexyl or phenyl, R ₇ and R ₈ may be the same or different and selected from H or methyl, and n is 0-8, preferably 3-5.

Further, the preparation method is:

(1) Weighing a framework balanced cationic compound, a silicon source, a framework trivalent element X source, an organic structure directing agent and deionized water according to stoichiometric quantities, adding them into an open container in the order of liquid phase first and solid phase second, and mixing them evenly under magnetic stirring to obtain an initial synthetic gel.

(2) Stirring the synthetic gel for aging at room temperature for 12-24 hours, and then aging it in an oven at 60-100°C for 2-6 hours, while removing excess solvent and water. The final synthetic gel has a molar ratio of SiO ₂ :mM ₂ O:xX ₂ O ₃ :qQ(OH) ₂ :hH ₂ O, wherein M is a framework balancing cation, X is a framework trivalent element, and Q is a cationic group of an organic structure directing agent, and the value ranges of m, x, q and h are: m=0-1, x=0-0.5, q=0.1-1, h=3-100. The preferred range is: m=0-0.15x=0-0.1, q=0.1-0.3, h=5-50.

(3) The synthetic gel is transferred to a polytetrafluoroethylene liner, placed in a stainless steel synthesis kettle, sealed, and finally placed in an oven for crystallization. The crystallization temperature is 50-250°C, preferably 100-200°C; the crystallization time is 1-30 days, preferably 5-15 days; the crystallization method is static or/and rotational crystallization.

(4) After washing and drying, the crystallization reaction product is calcined at 500-1000°C in air or/and inert atmosphere for 3-24 hours to remove the organic structure directing agent and obtain aluminosilicate zeolite molecular sieve. The calcination temperature is preferably 550-750°C and the calcination time is preferably 6-12 hours.

In addition, during the synthesis of the zeolite molecular sieve, seed crystals may be further added during the gel synthesis process. The seed crystals are the zeolite molecular sieve synthesized in the above step (3), and are in the form of a molecular sieve before or after calcination.

In the above-mentioned synthesis process, the source of the framework trivalent element X is selected from at least one of a boron source, an aluminum source, a gallium source, an indium source, an iron source and a chromium source; the boron source is selected from at least one of boric acid, sodium tetraborate, amorphous boron oxide, potassium borate, sodium metaborate, ammonium tetraborate and an organic boron ester; the aluminum source is selected from at least one of aluminum sulfate, sodium aluminate, aluminum nitrate, aluminum chloride, pseudo-boehmite, aluminum oxide, aluminum hydroxide, silica-aluminum zeolite molecular sieve, aluminum carbonate, elemental aluminum, aluminum isopropoxide and aluminum acetate; the gallium, indium and chromium sources can be selected from at least one of gallium oxide, gallium nitrate, indium oxide, indium nitrate, chromium chloride and chromium nitrate, etc.; the iron source is selected from at least one of ferric sulfate, ferric nitrate, ferric halide, ferrocene and ferric citrate; the framework balanced cationic compound is selected from hydroxide (such as hydroxide The invention relates to a method for preparing the silicon source. The method comprises the following steps: the step of preparing the silicon source: a silicon source selected from the group consisting of tetraethyl orthosilicate, silica sol, fumed silica, silicic acid and water glass; a silicon source selected from the group consisting of tetraethyl orthosilicate, silica sol, fumed silica, silicic acid and water glass; and a non-silicon tetravalent skeleton element source (Y) is added to the silicon source in an amount greater than or equal to 0 and less than or equal to 10w% of the mass of the silicon source, wherein Y is selected from at least one of germanium, tin, titanium, zirconium and hafnium.

A molecular sieve composition contains the silicate zeolite molecular sieve precursor and/or the silicate zeolite molecular sieve.

An application of the novel silicate zeolite molecular sieve, the application of the silicate zeolite molecular sieve or the molecular sieve composition as an energy storage material, chemical sensing material, carrier, adsorbent, separation agent or catalyst.

Furthermore, the silicate zeolite molecular sieve or the molecular sieve composition is used as an energy storage material, a chemical sensing material, a carrier, an adsorption separation agent or a catalyst.

Among them, in terms of energy storage material applications, it can be used as a storage material for hydrogen and hydrogen mixed media (such as hydrogen-methane, hydrogen-ethane and hydrogen-propane systems).

Among them, in the application of chemical sensing materials, it can be used to monitor light hydrocarbons, alkaline molecules, carbon dioxide, sulfide gas and humidity, etc.

Among them, in terms of carrier application, it can be used to carry metals, non-metals and bio-enzymes to prepare catalysts, and to carry drugs for imaging and treatment.

Among them, in terms of adsorption separation agent application, it can be used as a desiccant to remove water, adsorb volatile organic compounds (VOCs), treat wastewater containing dye macromolecules, and separate sugar and protein small molecules. More specifically, due to its regular ultra-large micropore channels, it can be used as a high-performance liquid chromatography column filler.

Among them, in terms of catalyst application, it can be used for hydrogenation or direct catalytic cracking of vacuum gas oil (VGO) to produce gasoline, diesel and other chemicals, hydrogenation or direct catalytic cracking of vacuum residue to produce oil products and olefins and other chemicals, other fossil energy and renewable energy conversion to produce high value-added chemicals, and isomerization, disproportionation and Friedel-Crafts alkylation reactions involving organic macromolecular substrates. More specifically, given its unique 10-membered ring micropores, the application of this molecular sieve in the cracking process of VGO and vacuum residue will be conducive to the production of low-carbon olefins, especially ethylene and propylene, which is of great significance for the upgrading and utilization of fossil energy in my country.

The advantages of the present invention are:

The present invention designs a ditricyclohexyl/phenyl quaternary phosphonium cation as an organic structure directing agent to synthesize A novel aluminosilicate zeolite molecular sieve with a three-dimensional open framework structure has a unique powder X-ray diffraction peak and a three-dimensional pore system consisting of one super-large micropore and two medium-micropores.

The molecular sieve of the present invention can be further applied to adsorption, separation or catalysis processes involving macromolecules due to its novel topological structure, unique pore system, and high thermal and hydrothermal stability, and may exhibit unique properties.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a powder X-ray diffraction spectrum of a freshly synthesized zeolite molecular sieve precursor provided in Examples 3-5 of the present invention, and a zeolite molecular sieve ZMQ-1 calcined at 600° C. for 6 hours and 800° C. for 1 hour.

2 is a powder X-ray diffraction spectrum of ZMQ-1 of the zeolite molecular sieve calcined at 600° C. provided in Example 3-5 of the present invention after being treated with 50% water vapor at 600° C., 700° C. and 800° C. for 3 hours.

FIG. 3 is an argon adsorption isotherm and pore size distribution curve of the ZMQ-1 zeolite molecular sieve calcined at 600° C. for 6 hours provided in Example 3 of the present invention.

FIG. 4 is a scanning electron microscope photograph of the ZMQ-1 zeolite molecular sieve provided in Example 3 of the present invention after calcination at 600° C. for 6 hours.

FIG5 is a transmission electron microscope photograph of the ZMQ-1 zeolite molecular sieve provided in Example 3 of the present invention after calcination at 600° C. for 6 hours.

FIG. 6 is a topological structure diagram of the ZMQ-1 zeolite molecular sieve after calcination at 600° C. for 6 hours provided in Example 3 of the present invention.

DETAILED DESCRIPTION

The specific implementation modes of the present invention are further described below in conjunction with examples. It should be noted that the specific implementation modes described here are only for illustrating and explaining the present invention, and are not limited to the present invention.

In Examples 3-10, the powder X-ray diffraction data of the samples were analyzed using a Japanese Rigaku X-ray diffractometer, model LabView, with a CuKα X-ray source and a wavelength of The argon adsorption and desorption analysis of the samples was performed using an American Quantachrome adsorption instrument, model Autosorb iQ. The elemental analysis of the samples was performed using an American Agilent (formerly Varian) ICP-730ES inductively coupled plasma emission spectrometer. The scanning electron microscope and transmission electron microscope photos of the samples were collected from Japan Hitachi Cold Field Emission scanning electron microscope S-4800 and JEOL high-resolution transmission electron microscope JEM-F200.

The synthesis method of the molecular sieve prepared in the following examples is hydrothermal crystallization, and the organic structure directing agent used is diquaternary ammonium/phosphonium cations of different lengths, and the organic structure directing agent is selected from any one or more of the following table.

Table 1

Among the organic structure directing agents, any one or more of organic structure directing agents 3, 4, 9, and 10 are more preferred.

Example 1: Synthesis of organic structure directing agent

Take the synthesis of organic structure directing agent 4 as an example. Weigh 36.51g of tricyclohexylphosphine into a 500mL three-necked round-bottom flask, add 200mL of chloroform, stir magnetically to dissolve, and transfer to an ice bath. Under magnetic stirring, slowly drop 13.88g of 1,8-dibromooctane into the flask, and continue to stir the resulting mixture solution for 1 hour. Subsequently, it was refluxed and heated at 75°C for 3 days. After the resulting mixture was naturally cooled to room temperature, excess ethyl acetate was added to precipitate the product, filtered, washed with ethyl acetate, and the residual solvent was removed by rotary evaporation to obtain a final product of 39.16g with a yield of 94%. It was determined to be the target compound by liquid phase nuclear magnetic resonance and CHN elemental analysis.

In a plastic beaker, dissolve the organic structure directing agent powder in 200mL of deionized water, then pour in the pre-activated Zhengzhou Xidian ZXUR-90 strong base anion exchange resin, and stir magnetically for 12 hours. Filter, wash, recover the filtrate, and obtain a concentrated organic structure directing agent solution after rotary evaporation. Take a small amount of solution, dilute it to 50mL with water, take 1.00g of 0.1mol/L hydrochloric acid standard solution, add phenol as an indicator, and titrate with the diluted organic structure directing agent solution to determine that the final exchange degree is 95%.

Example 2: Synthesis of organic structure directing agent

Take the synthesis of organic structure directing agent 10 as an example. Weigh 36.51g of tricyclohexylphosphine into a 500mL three-necked round-bottom flask, add 200mL of chloroform, stir magnetically to dissolve, and transfer to an ice bath. Under magnetic stirring, slowly drop 15.31g of 1,8-dibromo-2,7-dimethyloctane into the flask, and continue to stir the resulting mixture solution for 1 hour. Subsequently, it was refluxed at 75°C for 3 days. After the resulting mixture was naturally cooled to room temperature, excess ethyl acetate was added to precipitate the product, filtered, washed with ethyl acetate, and the residual solvent was removed by rotary evaporation to obtain a final product of 40.99g with a yield of 95%. It was confirmed as the target compound by liquid phase nuclear magnetic resonance and CHN elemental analysis.

In a plastic beaker, dissolve the organic structure directing agent powder in 200mL of deionized water, then pour in the pre-activated Zhengzhou Xidian ZXUR-90 strong base anion exchange resin, and stir magnetically for 12 hours. Filter, wash, recover the filtrate, and obtain a concentrated organic structure directing agent solution after rotary evaporation. Take a small amount of solution, dilute it to 50mL with water, take 1.00g of 0.1mol/L hydrochloric acid standard solution, add phenol as an indicator, and titrate with the diluted organic structure directing agent solution to determine that the final exchange degree is 97%.

Meanwhile, according to the preparation process described in the above-mentioned Example 1 or 2, the phosphorus cation is replaced by a nitrogen cation, or the substituent group or the methylene chain length connected to the phosphorus/nitrogen cation is replaced to obtain other organic structure directing agents described in Table 1.

Example 3: Synthesis of zeolite molecular sieve

The synthetic gel was prepared according to the molar ratio of SiO ₂ :0.02Al ₂ O ₃ :0.25Q(OH) ₂ :10H ₂ O, and the specific steps were as follows: 6 mmol of the organic structure directing agent solution described in Example 1 was weighed, 0.21 g of aluminum isopropoxide was added, and magnetic stirring was performed for 1 hour, followed by the addition of 5.21 g of tetraethyl orthosilicate, and the resulting mixture was stirred at room temperature for 12 hours. The resulting transparent gel was placed in a vacuum oven and heated at 100° C. for 3 hours to remove the solvent and excess water. The final synthetic gel was transferred to a 25 mL stainless steel synthesis kettle with a polytetrafluoroethylene liner and crystallized at 190° C. for 10 days. The product was filtered and washed with 200 mL of water, 200 mL of ethanol, and 100 mL of acetone, and dried overnight to obtain a freshly synthesized zeolite molecular sieve precursor. Subsequently, the product was calcined at 600° C. for 6 hours in a muffle furnace under a flowing air atmosphere to remove the organic structure directing agent. The product was identified as ZMQ-1 by powder X-ray diffraction, and the silicon-aluminum atomic ratio was 15.9 by ICP-OES elemental analysis.

Example 4: Calcination of Zeolite Molecular Sieve

The freshly synthesized zeolite molecular sieve precursor prepared in Example 3 was placed in a muffle furnace and calcined at 800° C. for 1 hour under a flowing air atmosphere to remove the organic structure directing agent. The product was determined to be ZMQ-1 by powder X-ray diffraction, as shown in FIG1 .

Example 5: Hydrothermal treatment of zeolite molecular sieve

The sample calcined at 600°C in Example 3 was divided into three parts, and placed in fixed bed reactors respectively. Deionized water was introduced into the reactor through a peristaltic pump under nitrogen atmosphere, and the relative humidity was maintained at 50%. The samples were treated at 600°C, 700°C and 800°C for 3 hours respectively. After cooling naturally to room temperature, the treated zeolite molecular sieve was taken out, and the phase was still ZMQ-1 as determined by powder X-ray diffraction, as shown in FIG2 .

Example 6: Zeolite Molecular Sieve Synthesis

The synthetic gel was prepared according to the molar ratio of SiO ₂ :0.01Al ₂ O ₃ :0.25Q(OH) ₂ :10H ₂ O. The specific steps are as follows: weigh 6 mmol of the organic structure directing agent solution described in Example 1, add 0.10 g of aluminum isopropoxide, stir magnetically for 1 hour, then add 5.21 g of tetraethyl orthosilicate, stir the resulting mixture at room temperature for 12 hours, and place the resulting transparent gel in a vacuum oven, heat at 100°C for 3 hours to remove the solvent and excess water. The final synthetic gel was transferred to a 25 mL stainless steel synthesis kettle with a polytetrafluoroethylene liner and crystallized at 190°C for 10 days. The product was filtered and washed with 200 mL of water, 200 mL of ethanol, and 100 mL of acetone, and dried overnight to obtain a freshly synthesized zeolite molecular sieve precursor. Subsequently, it was calcined at 600°C for 6 hours in a muffle furnace under a flowing air atmosphere to remove the organic structure directing agent. The product was identified as ZMQ-1 by powder X-ray diffraction, and the silicon-aluminum atomic ratio was 35.2 by ICP-OES elemental analysis.

Example 7: Synthesis of zeolite molecular sieve

The synthetic gel was prepared according to the molar ratio of SiO ₂ :0.005Al ₂ O ₃ :0.25Q(OH) ₂ :10H ₂ O, and the specific steps were as follows: 6 mmol of the organic structure directing agent solution described in Example 1 was weighed, 0.05 g of aluminum isopropoxide was added, and magnetic stirring was performed for 1 hour, followed by the addition of 5.21 g of tetraethyl orthosilicate, and the resulting mixture was stirred at room temperature for 12 hours. The resulting transparent gel was placed in a vacuum oven and heated at 100° C. for 3 hours to remove the solvent and excess water. The final synthetic gel was transferred to a 25 mL stainless steel synthesis kettle with a polytetrafluoroethylene liner and crystallized at 190° C. for 10 days. The product was filtered and washed with 200 mL of water, 200 mL of ethanol, and 100 mL of acetone, and dried overnight to obtain a freshly synthesized zeolite molecular sieve precursor. Subsequently, the product was calcined at 600° C. for 6 hours in a muffle furnace under a flowing air atmosphere to remove the organic structure directing agent. The product was identified as ZMQ-1 by powder X-ray diffraction, and the silicon-aluminum atomic ratio was determined to be 67.5 by ICP-OES elemental analysis.

Example 8: Synthesis of zeolite molecular sieve

The synthetic gel was prepared according to the molar ratio of SiO ₂ :0.02Al ₂ O ₃ :0.25Q(OH) ₂ :10H ₂ O, and the specific steps were as follows: 6 mmol of the organic structure directing agent solution described in Example 2 was weighed, 0.21 g of aluminum isopropoxide was added, and magnetic stirring was performed for 1 hour, followed by the addition of 5.21 g of tetraethyl orthosilicate, and the resulting mixture was stirred at room temperature for 12 hours. The resulting transparent gel was placed in a vacuum oven and heated at 100° C. for 3 hours to remove the solvent and excess water. The final synthetic gel was transferred to a 25 mL stainless steel synthesis kettle with a polytetrafluoroethylene liner and crystallized at 190° C. for 15 days. The product was filtered and washed with 200 mL of water, 200 mL of ethanol, and 100 mL of acetone, and dried overnight to obtain a freshly synthesized zeolite molecular sieve precursor. Subsequently, the product was calcined at 600° C. for 6 hours in a muffle furnace under a flowing air atmosphere to remove the organic structure directing agent. The product was identified as ZMQ-1 by powder X-ray diffraction, and the silicon-aluminum atomic ratio was 15.3 by ICP-OES elemental analysis.

Example 9: Zeolite Molecular Sieve Synthesis

A synthetic gel was prepared according to the molar ratio of SiO ₂ :0.02Na ₂ O:0.02Al ₂ O ₃ :0.25Q(OH) ₂ :10H ₂ O, and the specific steps were as follows: an appropriate amount of the organic structure directing agent solution described in Example 1 was weighed, 0.04 g of sodium hydroxide was added and stirred until dissolved, 0.21 g of aluminum isopropoxide was added, and magnetic stirring was performed for 1 hour, followed by addition of 5.21 g of tetraethyl orthosilicate, and the resulting mixture was stirred at room temperature for 12 hours. The resulting transparent gel was placed in a vacuum oven and heated at 100° C. for 3 hours to remove the solvent and excess water. The final synthetic gel was transferred to a 25 mL stainless steel synthesis reactor with a polytetrafluoroethylene liner and crystallized at 190°C for 5 days. The product was filtered and washed with 200 mL of water, 200 mL of ethanol, and 100 mL of acetone, and dried overnight to obtain a freshly synthesized zeolite molecular sieve. Subsequently, it was calcined at 600°C for 6 hours in a muffle furnace under a flowing air atmosphere to remove the organic structure directing agent. The product was determined to be ZMQ-1 by powder X-ray diffraction, and the ICP-OES elemental analysis showed that the silicon-aluminum atomic ratio was 15.9.

Example 10: Synthesis of zeolite molecular sieve

The synthetic gel was prepared according to the molar ratio of SiO ₂ :0.02Na ₂ O:0.02Al ₂ O ₃ :0.25Q(OH) ₂ :10H ₂ O, and the specific steps were as follows: weigh an appropriate amount of the organic structure directing agent solution described in Example 2, add 0.04g of sodium hydroxide and stir until dissolved, add 0.21g of aluminum isopropoxide, stir magnetically for 1 hour, then add 5.21g of tetraethyl orthosilicate, stir the mixture at room temperature for 12 hours, and place the obtained transparent gel in a vacuum oven, heat at 100°C for 3 hours to remove the solvent and excess water. The final synthetic gel was transferred to a 25mL stainless steel synthesis kettle with a polytetrafluoroethylene liner and crystallized at 190°C for 5 days. The product was filtered and washed with 200mL of water, 200mL of ethanol, and 100mL of acetone, and dried overnight to obtain a freshly synthesized zeolite molecular sieve. Subsequently, it was calcined at 600°C for 6 hours in a muffle furnace under a flowing air atmosphere to remove the organic structure directing agent. The product was identified as ZMQ-1 by powder X-ray diffraction, and the silicon-aluminum atomic ratio was 16.5 by ICP-OES elemental analysis.

For the different molecular sieves ZMQ-1 obtained in the above examples, continuous rotating electron diffraction (cRED) was used to obtain three-dimensional diffraction data and perform structural analysis. The results show that the structure of the ZMQ-1 molecular sieve has orthogonal symmetry and is a Cmmm space group. The unit cell parameters obtained are:

a＝19.58800, b＝56.51200, c＝21.05700,

And the powder X-ray diffraction spectrum of the zeolite molecular sieve synthesized in Examples 3-5 is shown in Figure 1. Both the freshly synthesized and calcined products give clear and unique characteristic diffraction peaks. The diffraction peaks of the samples calcined at 600°C and 800°C determine that the phase is ZMQ-1 molecular sieve, confirming that it has high thermal stability. Figure 2 shows the X-ray diffraction peaks of the product after 50% water vapor treatment, all of which are ZMQ-1 molecular sieves, confirming that the aluminosilicate molecular sieve has high hydrothermal stability. The argon physical adsorption data of the calcined zeolite molecular sieve confirms that the molecular sieve has a high micropore adsorption capacity, containing medium-micropores and ultra-large micropore structures, as shown in Figure 3. Figures 4 and 5 are scanning electron microscope and transmission electron microscope photos of the sample calcined at 600°C in Example 3, respectively, and the grains are all tetrahedral morphology. Figure 6 is the topological structure of the molecular sieve calcined at 600°C in Example 3, and it can be seen that there are 28-membered ring channels along the c-axis direction and 10-membered ring channels along the a and b-axis directions.

Claims (10)

A silicate zeolite molecular sieve precursor, characterized in that the anhydrous chemical composition of the silicate zeolite molecular sieve precursor is _SiO2 ·1/ _xXO1.5 · _mMO0.5 ·qQ, wherein X is a framework trivalent element, the Si/X molar ratio x≥5, M is a framework balancing cation, the M/Si molar ratio 0≤m≤1, and Q is a diquaternary ammonium or diquaternary phosphorus organic structure directing agent, and the Q/Si molar ratio q≥0.01. The silicate zeolite molecular sieve precursor according to claim 1 is characterized in that: the silicate zeolite molecular sieve precursor powder X-ray diffraction characteristics are as follows:

A novel silicate zeolite molecular sieve, characterized in that the anhydrous chemical composition of the silicate zeolite molecular sieve is SiO ₂ ·1/xXO _1.5 ·mMO _0.5 , wherein X is a framework trivalent element, Si/X molar ratio x≥5, M is a framework balanced cation, and M/Si molar ratio 0≤m≤1. The novel silicate zeolite molecular sieve according to claim 3 is characterized in that: the novel silicate zeolite molecular sieve contains a three-dimensional pore system composed of 28×10×10 rings, wherein the size of the 28-membered ring is The size of the 10-membered ring is The novel silicate zeolite molecular sieve according to claim 3 is characterized in that: the novel silicate zeolite molecular sieve has the powder X-ray diffraction characteristics shown in the following table:

The novel silicate zeolite molecular sieve according to any one of claims 3 to 5 is characterized in that the novel silicate zeolite molecular sieve is obtained by calcining the novel silicate zeolite molecular sieve precursor according to claim 1. The molecular sieve according to claim 1 or 3 is characterized in that: the framework trivalent element X is selected from at least one of boron, aluminum, gallium, indium, iron and chromium; the framework balanced cation M is selected from at least one of hydrogen ion, ammonium ion, lithium ion, sodium ion, potassium ion, rubidium ion and cesium ion; the silicon in the molecular sieve contains a non-silicon tetravalent framework element (Y) whose mass is greater than or equal to 0 and less than or equal to 10w%, wherein Y is selected from at least one of germanium, tin, titanium, zirconium and hafnium. A method for preparing a novel silicate zeolite molecular sieve according to claim 3, characterized in that: a framework balanced cationic compound, a silicon source, a framework trivalent element X source, an organic structure directing agent and water to obtain a synthetic gel; then aging and hydrothermally crystallizing the synthetic gel, and calcining the crystallized product to remove the organic structure directing agent; wherein the molar ratio of the synthetic gel after aging is _SiO2 : _mM2O : _xX2O3 : _qQ (OH) ₂ : _hH2O , wherein M is a framework balancing cation, X is a framework trivalent element, and Q is a cationic group of the organic structure directing agent, and the value ranges of m, x, q and h are: m=0-1, x=0-0.5, q=0.1-1, and h=3-100; The organic structure directing agent has the following configuration:
Wherein, Q may be the same or different and selected from nitrogen or phosphorus, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different and selected from cyclohexyl or phenyl, R ₇ and R ₈ are H or methyl, and n is 0-8. A molecular sieve composition, characterized in that the composition contains the silicate zeolite molecular sieve precursor according to claim 1 and/or the silicate zeolite molecular sieve according to claim 3. An application of the novel silicate zeolite molecular sieve as claimed in claim 3, characterized in that the silicate zeolite molecular sieve as claimed in claim 3 or the molecular sieve composition as claimed in claim 9 is used as an energy storage material, chemical sensing material, carrier, adsorbent, separation agent or catalyst.