An aluminum-rich framework SSZ-13 type molecular sieve membrane, its preparation method and application

Abstract

This invention belongs to the field of membrane separation technology and discloses an aluminum-rich framework SSZ-13 molecular sieve membrane, its preparation method, and its application. The preparation method includes: S1, dispersing seed crystals in deionized water to prepare a seed crystal suspension, placing a porous support in the seed crystal suspension, allowing the seed crystals to adhere to the porous surface to form a support loaded with a seed crystal layer; S2, placing the support loaded with the seed crystal layer in a synthesis solution and heating to crystallize, obtaining a membrane material; S3, rinsing, drying, and calcining the membrane material to obtain an aluminum-rich framework SSZ-13 molecular sieve membrane. The mineralizing agent in the synthesis solution includes two or more of lithium hydroxide, sodium hydroxide, potassium hydroxide, and cesium hydroxide. The silicon source and aluminum source are represented in oxide form, and the molar ratio is SiO2:Al2O3 = 1:(0.025~0.25). This invention, by crystallizing in a gel system containing inorganic mineralizing agents and organic template agents, can significantly improve the interactive symbiotic state between crystals within the membrane, ultimately obtaining a continuous and dense SSZ-13 molecular sieve membrane layer.

Description

Technical Field

[0001] This invention belongs to the field of membrane separation technology, specifically relating to an aluminum-rich framework SSZ-13 molecular sieve membrane, its preparation method, and its application. Background Technology

[0002] Compared to traditional distillation separation technology, membrane separation technology has advantages such as simple equipment, high separation efficiency, and low energy consumption, especially in the separation of near-boiling or azeotropic systems. NaA-type molecular sieve membranes, due to their extremely low framework silicon-to-aluminum ratio (Si / Al=1), have shown great promise in the pervaporation dehydration of organic solvents. However, the poor stability of NaA-type molecular sieve membranes limits their large-scale application in acidic and high-water-content systems.

[0003] Compared to NaA-type molecular sieve membranes, SSZ-13 molecular sieve membranes have slightly smaller intrinsic pore sizes, and their framework silicon-to-aluminum ratio can be adjusted over a wide range (Si / Al = 2~∞). Therefore, the aluminum-rich framework of SSZ-13 molecular sieves can combine excellent hydrophilicity and stability, potentially solving the technical bottleneck that currently limits the application of molecular sieve membranes under harsh conditions such as acidity and high water content. However, preparing continuous and dense aluminum-rich framework SSZ-13 molecular sieve membranes remains a major challenge in the zeolite membrane field. Currently, aluminum-rich framework SSZ-13 molecular sieve membranes are generally synthesized using template-free processes, resulting in high alkalinity of the synthesis solution and difficulty in controlling the microstructure of the zeolite membrane. In particular, with a significant decrease in the silicon-to-aluminum atomic ratio in the precursor solution, the nucleation and growth processes of SSZ-13 molecular sieve membranes undergo considerable changes, making it difficult to effectively control membrane thickness and the interaction between crystals. Ultimately, this leads to generally low separation selectivity in SSZ-13 molecular sieve membranes, hindering their industrial application. Based on this, the present invention proposes a new preparation method to solve the above problems. Summary of the Invention

[0004] To address the aforementioned technical problems, the present invention aims to provide an aluminum-rich framework SSZ-13 molecular sieve membrane, its preparation method, and its application. By crystallizing in a gel system containing inorganic mineralizers and organic templates, the interactive symbiotic state between crystals within the membrane can be significantly improved, ultimately resulting in a continuous and dense SSZ-13 molecular sieve membrane layer.

[0005] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a method for preparing an aluminum-rich framework SSZ-13 type molecular sieve membrane, comprising the following steps: S1. Disperse the seed crystals in deionized water and ultrasonically disperse them to prepare a seed crystal suspension. Place the porous carrier in the seed crystal suspension so that the seed crystals adhere to the surface of the porous carrier to obtain a carrier loaded with a seed crystal layer. S2. Place the support loaded with the seed layer in the synthesis solution and heat it for crystallization. After the reaction is complete, the membrane material is obtained. S3. After rinsing and drying the membrane material, calcination is performed to obtain an aluminum-rich framework SSZ-13 type molecular sieve membrane. In step S2, the synthesis solution includes a silicon source, an aluminum source, a mineralizer, a template agent, and deionized water. The mineralizer includes any two or more of lithium hydroxide, sodium hydroxide, potassium hydroxide, and cesium hydroxide. The silicon source and aluminum source are represented in oxide form, and the molar ratio SiO2:Al2O3 is calculated as 1:(0.025~0.25).

[0006] Preferably, the silicon source and mineralizer are expressed in oxide form and calculated by molar ratio as Li2O:Na2O:K2O:Cs2O:SiO2=(0~0.3):(0~0.3):(0~0.3):(0~0.3):1, wherein at least two of the mineralizers among Li2O, Na2O, K2O, and Cs2O have a content that is not 0.

[0007] Preferably, the template agent includes one or more of N,N,N-trimethyl-1-adamantyl ammonium hydroxide (TMAdaOH), choline chloride, benzyltrimethylammonium hydroxide, and tetraethylammonium hydroxide; The silicon source is represented in oxide form, T:SiO2=(0.01~2):1, where T represents the template agent.

[0008] Preferably, when preparing the synthesis solution, the silicon source is represented in the form of an oxide, and the molar ratio is calculated as H2O:SiO2 = (10~200):1.

[0009] Preferably, the silicon source includes one or more of solid silica gel, silica sol, tetraethyl orthosilicate, and silica. Aluminum sources include one or more of aluminum isopropoxide, sodium aluminate, aluminum nitrate, aluminum chloride, aluminum hydroxide, aluminum oxide, metallic aluminum, boehmite, and boehmite.

[0010] Preferably, in step S1, the mass concentration of the seed crystal suspension is 0.01~20%.

[0011] Preferably, in step S2, the crystallization temperature is 100~250℃ and the crystallization time is 5~200 h.

[0012] Preferably, in step S3, the calcination temperature is 200~600℃ and the calcination time is 1~100 h.

[0013] In a second aspect, the present invention provides an aluminum-rich framework SSZ-13 type molecular sieve membrane, which is prepared by the above method, and the framework silicon-aluminum atomic ratio of the SSZ-13 type molecular sieve membrane is 2~20.

[0014] In a third aspect, the present invention proposes an application of an aluminum-rich framework SSZ-13 molecular sieve membrane for organic solvent dehydration and gas separation.

[0015] Beneficial effects: This invention relates to a method for synthesizing aluminum-rich framework SSZ-13 molecular sieve membranes based on inorganic mineralizers and organic templates. Due to the regulatory role of inorganic mineralizers and organic templates in the nucleation and growth process of molecular sieves, the interactive symbiotic relationship between zeolite molecular sieve grains within the membrane is significantly improved. The resulting molecular sieve membrane has a dense and continuous membrane layer, good hydrophilicity, and high acid resistance, and has broad industrial application prospects in organic solvent dehydration. Attached Figure Description

[0016] Figure 1 The images show SEM images of the surface and cross-section of the SSZ-13 molecular sieve membrane prepared in Example 1.

[0017] Figure 2 The image shows the XRD pattern of the SSZ-13 molecular sieve membrane prepared in Example 1.

[0018] Figure 3 SEM images of the surface and cross-section of the SSZ-13 molecular sieve membrane prepared in Comparative Example 1. Detailed Implementation

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0020] This invention proposes a method for preparing an aluminum-rich framework SSZ-13 type molecular sieve membrane, the steps of which are as follows: S1. Disperse the seed crystals in deionized water and ultrasonically disperse them to prepare a seed crystal suspension (e.g., mass fraction of 0.01~20%). Place the porous carrier in the seed crystal suspension so that the seed crystals adhere to the surface of the porous carrier to obtain a carrier loaded with a seed crystal layer. S2. Place the support loaded with the seed layer in the synthesis solution and heat it for crystallization. After the reaction is complete, the membrane material is obtained. S3. After rinsing and drying the membrane material, calcination is performed to obtain an aluminum-rich framework SSZ-13 type molecular sieve membrane. In step S2, the synthesis solution includes a silicon source, an aluminum source, a mineralizer, a template agent, and deionized water. The mineralizer includes any two or more of lithium hydroxide, sodium hydroxide, potassium hydroxide, and cesium hydroxide. The silicon source and aluminum source are expressed in oxide form. The molar ratio is SiO2:Al2O3 = 1:(0.025~0.25).

[0021] The molecular sieve membrane prepared in this invention differs from the conventional preparation method of molecular sieves (zeolite molecular sieve powder or zeolite molecular sieve bulk). Molecular sieve powder and molecular sieve membranes differ fundamentally in structure, preparation, performance, and applications. Molecular sieve membranes are continuous micron or submicron-sized thin layers formed by directional growth on porous supports (such as ceramics or metals). The crystals within the membrane interact and coexist to form selective permeation channels, rather than being aggregates of independent particles. Using conventional molecular sieve preparation methods would make it difficult to prepare molecular sieve membranes. The SSZ-13 type molecular sieve membrane synthesized in this invention using inorganic mineralizers and organic template agents has a silicon-to-aluminum atomic ratio of 2-20, making it an aluminum-rich SSZ-13 molecular sieve membrane. This invention combines inorganic mineralizers and organic templates to synergistically regulate the nucleation and growth of molecular sieves, significantly improving the symbiotic relationship between molecular sieve crystals within the membrane. The resulting molecular sieve membrane is dense and continuous, exhibiting advantages such as good hydrophilicity and high acid resistance, and has broad industrial application prospects in organic solvent dehydration and gas separation.

[0022] Preferably, the molar ratio is calculated as Al2O3:SiO2 = (0.025~0.15):1.

[0023] In step S1, the inorganic mineralizing agent is an inorganic base, which includes two or more of lithium hydroxide, sodium hydroxide, potassium hydroxide, and cesium hydroxide. That is, in this invention, the inorganic mineralizing agent contains at least two strong inorganic bases. Further, the silicon source and the inorganic mineralizing agent are expressed in oxide form, and calculated by molar ratio as Li₂O:Na₂O:K₂O:Cs₂O:SiO₂=(0~0.3):(0~0.3):(0~0.3):(0~0.3):1, wherein at least two of the mineralizing agents among Li₂O, Na₂O, K₂O, and Cs₂O have a content that is not zero.

[0024] It's easy to understand that for the ratio Li2O:Na2O:K2O:Cs2O:SiO2=(0~0.3):(0~0.3):(0~0.3):(0~0.3):1, the amount of unused inorganic base is 0, while the amount of used inorganic base is controlled within a certain proportion. For example, when the inorganic mineralizer contains two inorganic bases, the amount of the two used inorganic bases is determined within a certain proportion, while the amount of the other two unused inorganic bases is 0. Similarly, when the inorganic mineralizer contains three inorganic bases, the amount of the three used inorganic bases is determined within a certain proportion, while the amount of the other unused inorganic base is 0. When the inorganic mineralizer contains four inorganic bases, the amount of all four inorganic bases is determined within a certain proportion.

[0025] Preferably, the silicon source and inorganic mineralizer are expressed in oxide form, and the molar ratio is calculated as Li2O:Na2O:K2O:Cs2O:SiO2=(0~0.2):(0~0.2):(0~0.2):(0~0.2):1.

[0026] Silicon and aluminum sources are commonly used materials in the preparation of molecular sieve membranes. For example, silicon sources include one or more of solid silica gel, silica sol, tetraethyl orthosilicate and silica, and aluminum sources include one or more of aluminum isopropoxide, sodium aluminate, aluminum nitrate, aluminum chloride, aluminum hydroxide, aluminum oxide, metallic aluminum, boehmite and boehmite.

[0027] The template agent is a commonly used substance in the art for preparing molecular sieve membranes. For example, the template agent includes one or more of N,N,N-trimethyl-1-adamantyl ammonium hydroxide, choline chloride, benzyltrimethylammonium hydroxide, and tetraethylammonium hydroxide. Preferably, the silicon source is expressed in oxide form, with T:SiO2=(0.01~2):1, where T represents the template agent. Preferably, T:SiO2=(0.1~1):1.

[0028] When preparing the synthesis solution, the silicon source is expressed in oxide form. The preferred amount of deionized water, calculated by molar ratio, is H₂O:SiO₂ = (10~200):1. More preferably, H₂O:SiO₂ = (20~180):1.

[0029] In step S1, the carrier is preferably an alumina carrier. The mass concentration of the prepared seed crystal suspension is 0.01~20%. In this invention, the mass of the carrier is not limited.

[0030] The seed crystals are preferably those with a structure similar to that of the SSZ-13 molecular sieve membrane. More preferably, the seed crystals are CHA type seed crystals, and more preferably, the seed crystal particle size is 200~500 nm.

[0031] In step S1, the stirring temperature for preparing the synthesis solution and seed crystal suspension is preferably 20~30℃.

[0032] In step S2, the crystallization temperature is preferably 100~250℃, and the crystallization time is preferably 5~200 h. More preferably, the crystallization temperature is 120~200℃, and the crystallization time is preferably 10~180 h.

[0033] In step S3, the calcination temperature is 200~600℃ and the calcination time is 1~100 h.

[0034] The technical solution of the present invention will be described in detail below with specific embodiments.

[0035] Example 1 Silica sol, sodium aluminate, potassium hydroxide, lithium hydroxide, cesium hydroxide, N,N,N-trimethyl-1-adamantyl ammonium hydroxide (TMAdaOH) were mixed with water and stirred at room temperature for 12 h to obtain a synthesis solution. The silicon source, aluminum source, and mineralizer are expressed in oxide form. In the synthesis solution, the molar ratio of each raw material is SiO2:Al2O3:Na2O:Li2O:Cs2O:TMAdaOH:H2O=1:0.06:0.14:0.01:0.01:0.3:55. S1. SSZ-13 zeolite molecular sieves with a particle size of about 200~500 nm are dispersed in deionized water to prepare a 1wt% seed suspension and ultrasonically dispersed to make it uniform. The seed suspension is then attached to the surface of a porous alumina carrier by impregnation to obtain a carrier loaded with a seed layer. S2. The alumina carrier with pre-coated seed layer is vertically placed into a stainless steel reactor with a Teflon liner. After pouring in the membrane synthesis solution, the reactor is sealed and crystallized at 165°C for 72 h. After the reaction is completed, the synthesized membrane material is taken out. S3. The membrane material was washed with deionized water and then dried in an oven at 115℃. After calcination at 550℃ for 6 h, the SSZ-13 molecular sieve membrane was obtained.

[0036] Figure 1 The image shows an SEM image of an SSZ-13 molecular sieve membrane prepared on an alumina support. It can be seen that the crystals on the membrane surface have good interaction and symbiosis, the membrane layer is continuous and dense without obvious defects, and the thickness is about 5 μm. Figure 2 The XRD pattern of the SSZ-13 molecular sieve membrane prepared in this embodiment shows that, except for the characteristic peak of alumina, all other diffraction peaks are consistent with the characteristic peaks of SSZ-13, indicating that a pure-phase SSZ-13 molecular sieve membrane was successfully synthesized on the alumina support. The pervaporation dehydration separation performance of a 90 wt% tert-butanol / water system was tested at 70°C. The permeate flux of the membrane prepared in this embodiment was 2.5 kg m³. -2 h -1 The separation factor is 8200.

[0037] Example 2 Silica sol, aluminum hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide, N,N,N-trimethyl-1-adamantyl ammonium hydroxide, and water were mixed evenly and then stirred at room temperature for 12 h to obtain a synthesis solution. The silicon source, aluminum source, and mineralizer are expressed in oxide form. In the synthesis solution, the molar ratio of each raw material is SiO2:Al2O3:K2O:Li2O:Cs2O:TMAdaOH:H2O=1:0.05:0.12:0.015:0.01:0.25:45. S1. Disperse SSZ-13 zeolite molecular sieve seeds with a particle size of about 200-500 nm in deionized water to prepare a seed suspension of 1 wt% and sonicate it to make it uniformly dispersed. Use the impregnation method to attach the above seed suspension to the surface of a porous alumina carrier to obtain a carrier loaded with a seed layer. S2. The alumina carrier with pre-coated seed layer is vertically placed into a stainless steel reactor with a Teflon liner. After pouring in the membrane synthesis solution, the reactor is sealed and crystallized at 160°C for 48 hours. After the reaction is completed, the synthesized membrane material is taken out. S3. The membrane material was washed with deionized water and then dried in an oven at 115℃. After calcination at 550℃ for 6 h, the SSZ-13 molecular sieve membrane was obtained.

[0038] The membrane prepared in this embodiment was tested for pervaporation dehydration separation performance in a 60 wt% acetic acid / water system at 50°C. The membrane's permeation flux was 2.2 kg m³ / s. -2 h -1 The separation factor is 2400.

[0039] Example 3 Silica sol, aluminum hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, N,N,N-trimethyl-1-adamantyl ammonium hydroxide, and water were mixed evenly and then stirred at room temperature for 12 h to obtain a synthesis solution. The silicon source, aluminum source, and mineralizer are expressed in oxide form. In the synthesis solution, the molar ratio of each raw material is SiO2:Al2O3:Na2O:Li2O:Cs2O:TMAdaOH:H2O=1:0.05:0.1:0.02:0.01:0.28:50. S1. Disperse SSZ-13 zeolite molecular sieve seed crystals with a particle size of about 200~500 nm in deionized water to prepare a 1 wt% seed crystal suspension and sonicate it to make it uniformly dispersed. Use the impregnation method to attach the above seed crystal suspension to the surface of a porous alumina carrier to obtain a carrier loaded with a seed crystal layer. S2. The alumina carrier with pre-coated seed layer is vertically placed into a stainless steel reactor with a Teflon liner. After pouring in the membrane synthesis solution, the reactor is sealed and crystallized at 180°C for 48 hours. After the reaction is completed, the synthesized membrane material is taken out. S3. The membrane material was washed with deionized water and then dried in an oven at 115℃. After calcination at 550℃ for 6 h, the SSZ-13 molecular sieve membrane was obtained.

[0040] The membrane prepared in this embodiment was tested for pervaporation dehydration separation performance in a 90 wt% tert-butanol / water system at 70°C. The membrane's permeation flux was 2.8 kg m³ / s. -2 h -1 The separation factor is 5000.

[0041] Example 4 Silica sol, aluminum hydroxide, sodium hydroxide, cesium hydroxide, N,N,N-trimethyl-1-adamantyl ammonium hydroxide, and water were mixed evenly and then stirred at room temperature for 12 h to obtain a synthesis solution. The silicon source, aluminum source, and mineralizer are expressed in oxide form. In the synthesis solution, the molar ratio of each raw material is SiO2:Al2O3:Na2O:Cs2O:TMAdaOH:H2O=1:0.035:0.18:0.01:0.3:50. S1. Disperse SSZ-13 zeolite molecular sieve seeds with a particle size of about 200~500 nm in deionized water to prepare a seed suspension of 2 wt% and sonicate it to make it uniformly dispersed. Use the impregnation method to attach the above seed suspension to the surface of a porous alumina carrier to obtain a carrier loaded with a seed layer. S2. The alumina carrier with pre-coated seed layer is vertically placed into a stainless steel reactor with a Teflon liner. After pouring in the membrane synthesis solution, the reactor is sealed and crystallized at 175°C for 55 h. After the reaction is completed, the synthesized membrane material is taken out. S3. The membrane material was washed with deionized water and then dried in an oven at 115℃. After calcination at 550℃ for 6 h, the SSZ-13 molecular sieve membrane was obtained.

[0042] The membrane prepared according to this embodiment achieves a CO2 permeability of 3.5 × 10⁻⁶ at a temperature of 20°C. -7 mol Pa - 1 m -2 s -1 The ideal selectivity for CO2 / CH4 is 75%.

[0043] Comparative Example 1 Compared with Example 1, this comparative example does not add the organic template agent N,N,N-trimethyl-1-adamantyl ammonium hydroxide in step S1, and the other conditions are the same as in Example 1.

[0044] Figure 3 This is a SEM image of a zeolite membrane prepared on an alumina support, showing that a continuous and dense membrane layer could not be formed on the support. Pervaporation tests were performed on the above membrane with 90 wt% tert-butanol / water and 60 wt% acetic acid / water systems, respectively, and the results showed that the membrane had no separation performance for either system.

[0045] Comparative Example 2 Compared with Example 2, this comparative example does not add the organic template agent N,N,N-trimethyl-1-adamantyl ammonium hydroxide in step S1, and the other conditions are the same as in Example 2.

[0046] The membrane prepared in this comparative example was subjected to pervaporation tests on 90 wt% tert-butanol / water and 60 wt% acetic acid / water systems, respectively. The results showed that the membrane had no separation performance for either of these systems.

[0047] Comparative Example 3 Compared with Example 3, this comparative example does not add the organic template agent N,N,N-trimethyl-1-adamantyl ammonium hydroxide in step S1, and the other conditions are the same as in Example 3.

[0048] The membrane prepared in this comparative example was subjected to pervaporation tests on 90 wt% tert-butanol / water and 60 wt% acetic acid / water systems, respectively. The results showed that the membrane had no separation performance for either of these systems.

[0049] Comparative Example 4 Compared with Example 1, the mineralizer used in this comparative example is LiOH, and the other conditions are the same as in Example 1.

[0050] The membrane prepared in this comparative example was subjected to pervaporation test on a 90 wt% tert-butanol / water system. The results showed that the membrane had no separation performance for the above system.

[0051] Comparative Example 5 Compared with Example 1, the conditions in this comparative example are the same as those in Example 1, except that no mineralizing agent is added to the synthesis solution.

[0052] The membrane prepared in this comparative example was subjected to pervaporation tests on 90 wt% tert-butanol / water and 60 wt% acetic acid / water, respectively. The results showed that the membrane had no separation performance for either of the above systems.

[0053] Comparative Example 6 Compared with Example 1, the mineralizer used in this comparative example is NaOH, and the Na2O / SiO2 molar ratio is adjusted to 0.25. The other conditions are the same as in Example 1.

[0054] The membrane prepared in this comparative example was subjected to pervaporation tests on 90 wt% tert-butanol / water and 60 wt% acetic acid / water, respectively. The results showed that the membrane had no separation performance for either of the above systems.

[0055] Based on Examples 1-4 and Comparative Examples 1-6, it is evident that inorganic mineralizers and organic template agents play crucial roles in the synthesis of aluminum-rich framework SSZ-13 molecular sieve membranes in this invention. Their combined action effectively regulates the nucleation and growth of SSZ-13 molecular sieves. Without a template agent, without a mineralizer, or using only one mineralizer, it is impossible to prepare a usable molecular sieve membrane. The microstructure of the SSZ-13 molecular sieve membrane prepared by this invention is more easily controlled, thereby effectively improving the separation performance and reproducibility of the SSZ-13 molecular sieve membrane.

[0056] The embodiments provided by the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention, and the descriptions of the embodiments above are only for the purpose of helping to understand the core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing an alumina-rich framework SSZ-13 type molecular sieve membrane, characterized in that, Includes the following steps: S1. Disperse the seed crystals in deionized water and ultrasonically disperse them to prepare a seed crystal suspension. Place the porous carrier in the seed crystal suspension so that the seed crystals adhere to the surface of the porous carrier to obtain a carrier loaded with a seed crystal layer. S2. Place the support loaded with the seed layer in the synthesis solution and heat it for crystallization. After the reaction is complete, the membrane material is obtained. S3. After rinsing and drying the membrane material, calcination is performed to obtain an aluminum-rich framework SSZ-13 type molecular sieve membrane. In step S2, the synthesis solution includes a silicon source, an aluminum source, a mineralizer, a template agent, and deionized water. The mineralizer includes two or more of lithium hydroxide, sodium hydroxide, potassium hydroxide, and cesium hydroxide. The silicon source and aluminum source are expressed in oxide form. The molar ratio is SiO2:Al2O3 = 1:(0.025~0.25).

2. The preparation method according to claim 1, characterized in that, The silicon source and mineralizer are expressed in oxide form and calculated by molar ratio as Li2O:Na2O:K2O:Cs2O:SiO2=(0~0.3):(0~0.3):(0~0.3):(0~0.3):1, wherein at least two of the mineralizers in Li2O, Na2O, K2O and Cs2O have a content that is not 0.

3. The preparation method according to claim 1, characterized in that, Template agents include one or more of N,N,N-trimethyl-1-adamantyl ammonium hydroxide, choline chloride, benzyltrimethyl ammonium hydroxide, and tetraethyl ammonium hydroxide; The silicon source is represented in oxide form, T:SiO2=(0.01~2):1, where T represents the template agent.

4. The preparation method according to claim 1, characterized in that, When preparing the synthesis solution, the silicon source is represented in the form of oxide, and the molar ratio is calculated as H2O:SiO2 = (10~200):

1.

5. The preparation method according to claim 1, characterized in that, Silicon sources include one or more of solid silica gel, silica sol, tetraethyl orthosilicate, and silica. Aluminum sources include one or more of aluminum isopropoxide, sodium aluminate, aluminum nitrate, aluminum chloride, aluminum hydroxide, aluminum oxide, metallic aluminum, boehmite, and boehmite.

6. The preparation method according to any one of claims 1-5, characterized in that, In step S1, the mass concentration of the seed crystal suspension is 0.01~20%.

7. The preparation method according to any one of claims 1-5, characterized in that, In step S2, the crystallization temperature is 100~250℃ and the crystallization time is 5-200 h.

8. The preparation method according to any one of claims 1-5, characterized in that, In step S3, the calcination temperature is 200~600℃ and the calcination time is 1~100 h.

9. An alumina-rich framework SSZ-13 type molecular sieve membrane, characterized in that, The SSZ-13 molecular sieve membrane, prepared by the preparation method according to any one of claims 1-8, has a silicon-to-aluminum atomic ratio of 2 to 20 in its framework.

10. An application of an alumina-rich framework SSZ-13 type molecular sieve membrane, characterized in that, The aluminum-rich framework SSZ-13 molecular sieve membrane prepared by the preparation method according to any one of claims 1-8 is used in the fields of organic solvent dehydration and gas separation.

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