A method of making ssz-13 molecular sieve

Abstract

The application provides a preparation method of SSZ-13 molecular sieve, and relates to the technical field of waste material resource utilization and molecular sieve synthesis. The application mixes a template agent, an alkali source, water, industrial perlite waste material and a silicon source to obtain a mixture; the mixture is subjected to hydrothermal crystallization to obtain SSZ-13 molecular sieve; and the temperature of the hydrothermal crystallization is 160-170 DEG C. The application uses industrial perlite waste material as raw material to replace pure chemical reagents to synthesize zeolite molecular sieve, can solve the problems of treatment and storage of industrial perlite waste material, reduces production cost, and obtains SSZ-13 molecular sieve products with high added value; the application adopts high crystallization temperature, promotes effective utilization of silicon aluminum sources in industrial perlite waste material, can hydrothermally synthesize SSZ-13 molecular sieve with high crystallinity and purity in one step without activation pretreatment, simplifies operation steps, and greatly saves energy.

Description

Technical Field

[0001] This invention relates to the fields of waste resource utilization and molecular sieve synthesis technology, and particularly to a method for preparing SSZ-13 molecular sieve. Background Technology

[0002] Zeolite molecular sieves are an important class of inorganic microporous aluminosilicates with regular pore structures, good thermal stability, and modifiability. They are important inorganic porous materials with wide applications in petrochemical catalysis, small molecule adsorption and separation, and heavy metal wastewater treatment. To date, the International Ziele Association (IZA) Structure Committee has included more than 256 different molecular sieve framework structures.

[0003] Perlite is a naturally formed volcanic rock with a bound water content of 2-6%, mainly composed of quartz and alumina, characterized by its amorphous structure. When rapidly heated to 870℃, the bound water in perlite evaporates, forming an expanded structure, thus creating expanded perlite. Expanded perlite, with its high density and vesicular structure, can be used as a highly efficient thermal insulation material. However, during the production of expanded perlite, some perlite powder, due to its small crystal size (below 60 mesh), cannot expand at high temperatures, resulting in industrial perlite waste. This waste is highly volatile and difficult to store; excessive stockpiling can cause environmental problems. Developing industrial perlite waste into high-value-added zeolite molecular sieves is of great significance for realizing the resource reuse of industrial perlite waste. However, current methods for converting solid waste into zeolite generally require pretreatment steps such as acid activation, alkali activation, or high-temperature calcination to convert more of the silicon and aluminum components of the waste into effective silicon and aluminum raw materials for synthesizing molecular sieves. These methods are cumbersome and increase energy consumption. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a method for preparing SSZ-13 molecular sieve. This invention utilizes industrial perlite waste as raw material to synthesize a high-value-added SSZ-13 molecular sieve product, and achieves a simple one-step hydrothermal synthesis without activation pretreatment.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a method for preparing SSZ-13 molecular sieve, comprising the following steps:

[0007] A mixture is prepared by mixing a template agent, an alkali source, water, industrial perlite waste, and a silicon source; the alkali source is sodium hydroxide; the alkali source is calculated as Na2O, the industrial perlite waste is calculated as SiO2 and Al2O3, the silicon source is calculated as SiO2, and the molar ratio of SiO2, Al2O3, Na2O, template agent, and water in the mixture is (20-25):1:(2.31-3.85):(2.12-3.85):1692;

[0008] The mixture was subjected to hydrothermal crystallization to obtain SSZ-13 molecular sieve; the hydrothermal crystallization temperature was 160-170℃.

[0009] Preferably, the template agent is N,N,N-trimethyl-1-adamantyl ammonium hydroxide.

[0010] Preferably, the total mass content of SiO2 and Al2O3 in the industrial perlite waste is greater than 89%.

[0011] Preferably, the silicon source includes silica sol.

[0012] Preferably, the mixing method is as follows:

[0013] The template agent, alkali source and water are mixed in the first mixture to obtain the first mixture;

[0014] The first mixture is mixed with industrial perlite waste to obtain a second mixture;

[0015] The second mixture is then mixed with a silicon source in a third step to obtain the mixture.

[0016] Preferably, the molar ratio of SiO2, Al2O3, Na2O, template agent and water in the mixture is (20-25):1:(3.08-3.85):(2.69-3.85):1692.

[0017] Preferably, the hydrothermal crystallization time is 48–120 hours.

[0018] Preferably, the hydrothermal crystallization time is 72 hours.

[0019] Preferably, after hydrothermal crystallization, the resulting crystallized liquid is further subjected to solid-liquid separation, solid phase washing, and drying in sequence.

[0020] Preferably, the SSZ-13 molecular sieve has a crystalline morphology.

[0021] This invention provides a method for preparing SSZ-13 molecular sieve, comprising the following steps: mixing a template agent, an alkali source, water, industrial perlite waste, and a silicon source to obtain a mixture; the alkali source is sodium hydroxide; the alkali source is calculated as Na2O, the industrial perlite waste is calculated as SiO2 and Al2O3, the silicon source is calculated as SiO2, and the molar ratio of SiO2, Al2O3, Na2O, template agent, and water in the mixture is (20-25):1:(2.31-3.85):(2.12-3.85):1692; and subjecting the mixture to hydrothermal crystallization to obtain SSZ-13 molecular sieve; the hydrothermal crystallization temperature is 160-170℃. Compared with the prior art, this invention has the following advantages:

[0022] Beneficial effects:

[0023] This invention utilizes industrial perlite waste as raw material to synthesize zeolite molecular sieves, replacing pure chemical reagents. It can solve the problems of industrial perlite waste treatment and storage, while reducing production costs and obtaining SSZ-13 molecular sieve products with high added value.

[0024] This invention employs a high crystallization temperature to promote the effective utilization of silicon-aluminum sources in industrial perlite waste, enabling one-step hydrothermal synthesis of SSZ-13 molecular sieves without activation pretreatment, simplifying the operation steps and greatly saving energy.

[0025] This invention can synthesize SSZ-13 molecular sieves with good crystallinity and purity. Attached Figure Description

[0026] Figure 1 These are XRD patterns of the molecular sieves prepared in the examples and comparative examples;

[0027] Figure 2 The images shown are SEM images of the SSZ-13 molecular sieves prepared in Examples 1-5. Figure 2 In the examples, A1, A2, A3, A4, and A5 correspond to SSZ-13 molecular sieve products A1, A2, A3, A4, and A5, respectively. Detailed Implementation

[0028] This invention provides a method for preparing SSZ-13 molecular sieve, comprising the following steps:

[0029] A mixture is prepared by mixing a template agent, an alkali source, water, industrial perlite waste, and a silicon source; the alkali source is sodium hydroxide; the alkali source is calculated as Na2O, the industrial perlite waste is calculated as SiO2 and Al2O3, the silicon source is calculated as SiO2, and the molar ratio of SiO2, Al2O3, Na2O, template agent, and water in the mixture is (20-25):1:(2.31-3.85):(2.12-3.85):1692;

[0030] The mixture was subjected to hydrothermal crystallization to obtain SSZ-13 molecular sieve; the hydrothermal crystallization temperature was 160-170℃.

[0031] Unless otherwise specified, all raw materials involved in this invention are commercially available products well known in the art.

[0032] This invention mixes a template agent, an alkali source, water, industrial perlite waste, and a silicon source to obtain a mixture.

[0033] In this invention, the template agent is preferably N,N,N-trimethyl-1-adamantyl ammonium hydroxide (TMAdaOH), and in the embodiments of this invention, the template agent is specifically added in the form of a 25 wt% aqueous solution. In this invention, the alkali source is sodium hydroxide; the silicon source preferably includes silica sol. In this invention, the industrial perlite waste is waste formed during the production of expanded perlite when some perlite powder cannot expand at high temperatures due to its small grain size (below 60 mesh); the main components of the industrial perlite waste are quartz and alumina. In this invention, the total mass content of SiO2 and Al2O3 in the industrial perlite waste is preferably greater than 89%.

[0034] In this invention, the alkali source is calculated as Na2O, the industrial perlite waste is calculated as SiO2 and Al2O3, the silicon source is calculated as SiO2, and the molar ratio of SiO2, Al2O3, Na2O, template agent, and water in the mixture is (20-25):1:(2.31-3.85):(2.12-3.85):1692, preferably (20-25):1:(3.08-3.85):(2.69-3.85):1692. In the embodiments of this invention, the elemental content of the industrial perlite waste used was determined by X-ray fluorescence spectroscopy, and the molar ratio was calculated based on a SiO2 content of 76.1 wt% and an Al2O3 content of 13.5 wt%. By controlling the molar ratio of SiO2, Al2O3, Na2O, template agent, and water in the mixture within the above range, this invention can more effectively utilize the silicon and aluminum components in the industrial perlite waste to achieve the preparation of SSZ-13 molecular sieves.

[0035] In this invention, the mixing method is preferably:

[0036] The template agent, alkali source and water are mixed in the first mixture to obtain the first mixture;

[0037] The first mixture is mixed with industrial perlite waste to obtain a second mixture;

[0038] The second mixture is then mixed with a silicon source in a third step to obtain the mixture.

[0039] In this invention, the template agent and the alkali source are preferably added to water for a first mixing. In this invention, the first mixture is preferably cooled to room temperature, and then industrial perlite waste is added for a second mixing. In this invention, a silicon source is preferably added to the second mixture (suspension) for a third mixing. In this invention, the first, second, and third mixing are preferably carried out by stirring at room temperature, i.e., no additional heating is required, and the stirring is sufficient to ensure that all components are uniformly mixed.

[0040] The present invention employs the above-mentioned mixing method, first mixing the template agent and the alkali source (together serving as structure directing agents) evenly, and then adding the silicon source and aluminum source to make the reaction more complete.

[0041] After obtaining the mixture, the present invention performs hydrothermal crystallization on the mixture to obtain SSZ-13 molecular sieve. In the present invention, the hydrothermal crystallization temperature is 160-170°C; the hydrothermal crystallization time is preferably 48-120 h, more preferably 72 h. The present invention preferably transfers the mixture to a stainless steel reactor with a polytetrafluoroethylene liner for the hydrothermal crystallization. The present invention uses a high crystallization temperature, which can promote the effective utilization of silicon-aluminum sources in industrial perlite waste, and can synthesize SSZ-13 molecular sieve in one step hydrothermally without activation pretreatment. Compared with the acid activation, alkali activation, or high-temperature calcination pretreatment steps widely used in solid waste zeolite treatment, the present invention simplifies the operation steps and greatly saves energy.

[0042] Following the hydrothermal crystallization, the present invention preferably further subjectes the obtained crystallization solution to solid-liquid separation, solid-phase washing, and drying sequentially to obtain SSZ-13 molecular sieve. The present invention does not have particular requirements for the solid-liquid separation method; any solid-liquid separation method well-known to those skilled in the art, such as filtration, can be used. In the present invention, the washing is preferably water washing, and the pH value of the product after washing is preferably 7-10, more preferably 9. The present invention does not have particular requirements for the drying temperature; in the embodiments of the present invention, the drying temperature is 75°C, and the time is 24 hours.

[0043] In this invention, the SSZ-13 molecular sieve has a crystalline morphology.

[0044] The topological structure of SSZ-13 molecular sieve is CHA. CHA-type molecular sieves are composed of composite building units (CBUs) and cages, possessing a three-dimensional pore structure. In the (001) direction, the pore diameter of the CHA molecular sieve is... It is a typical eight-membered ring small-pore molecular sieve. Among them, the CHA type molecular sieve with a silica-alumina ratio of ≥2.5 is generally also known as SSZ-13 molecular sieve.

[0045] This invention provides a novel method for hydrothermal synthesis of SSZ-13 molecular sieves using untreated industrial perlite waste as raw material at a certain temperature. The resulting molecular sieve exhibits crystalline morphology and high crystallinity and purity.

[0046] To further illustrate the present invention, the preparation method of SSZ-13 molecular sieve provided by the present invention will be described in detail below with reference to examples, but these should not be construed as limiting the scope of protection of the present invention.

[0047] Example 1

[0048] The steps for preparing SSZ-13 molecular sieve using industrial perlite waste as raw material are as follows:

[0049] (1) Add 0.523g of N,N,N-trimethyl-1-adamantyl ammonium hydroxide (TMAdaOH) aqueous solution (mass fraction of 25%) and 0.042g of sodium hydroxide to 6.1mL of water and stir until homogeneous.

[0050] (2) After the solution obtained in step (1) has cooled to room temperature, add 0.174g of industrial perlite waste and stir for 3h.

[0051] (3) Add 0.709 g of silica sol (SiO2 mass fraction of 30%) to the suspension obtained in step (2), stir evenly at room temperature for 1 h, and the molar ratio of effective components in the resulting mixture is 25SiO2:Al2O3:2.31Na2O:2.69TMAdaOH:1692H2O.

[0052] (4) The mixture obtained in step (3) is transferred to a stainless steel reactor with a polytetrafluoroethylene liner for hydrothermal crystallization at a temperature of 170°C for 72 hours.

[0053] (5) The crystallized product was collected by filtration, washing (washing until the product pH was 9) and drying. The drying temperature was 75℃ and the drying time was 24h to obtain SSZ-13 molecular sieve product, which was denoted as product A1.

[0054] XRD testing was performed on product A1. Figure 1 Curve A1 in the graph corresponds to the XRD test results of product A1. It can be seen that curve A1 is consistent with the standard spectrum, indicating that it is a pure phase with high crystallinity.

[0055] SEM electron microscopy was performed on product A1, and the results are as follows: Figure 2 A1 in the sample shows that the product has a crystalline morphology.

[0056] Example 2

[0057] The steps for preparing SSZ-13 molecular sieve using industrial perlite waste as raw material are as follows:

[0058] (1) Add 0.523g of TMAdaOH aqueous solution (mass fraction of 25%) and 0.057g of sodium hydroxide to 6.1mL of water and stir until homogeneous.

[0059] (2) After the solution obtained in step (1) has cooled to room temperature, add 0.174g of industrial perlite waste and stir for 3h.

[0060] (3) Add 0.709 g of silica sol (SiO2 mass fraction of 30%) to the suspension obtained in step (2), stir evenly at room temperature for 1 h, and the molar ratio of effective components in the resulting mixture is 25SiO2:Al2O3:3.08Na2O:2.69TMAdaOH:1692H2O.

[0061] (4) The mixture obtained in step (3) is transferred to a stainless steel reactor with a polytetrafluoroethylene liner for hydrothermal crystallization at a temperature of 170°C for 72 hours.

[0062] (5) The crystallized product was collected by filtration, washing (washing until the product pH was 9) and drying. The drying temperature was 75℃ and the drying time was 24h to obtain SSZ-13 molecular sieve product, which was denoted as product A2.

[0063] XRD testing was performed on product A2. Figure 1 The XRD test results of product A2 corresponding to curve A2 show that curve A2 is consistent with the standard spectrum and is a pure phase.

[0064] SEM electron microscopy was performed on product A2, and the results are as follows: Figure 2 A2 in the sample shows that the product has a crystalline morphology.

[0065] Example 3

[0066] The steps for preparing SSZ-13 molecular sieve using industrial perlite waste as raw material are as follows:

[0067] (1) Add 0.411g of TMAdaOH aqueous solution (mass fraction of 25%) and 0.071g of sodium hydroxide to 6.2mL of water and stir until homogeneous.

[0068] (2) After the solution obtained in step (1) has cooled to room temperature, add 0.174g of industrial perlite waste and stir for 3h.

[0069] (3) Add 0.709g of silica sol (SiO2 mass fraction of 30%) to the suspension obtained in step (2), stir evenly at room temperature for 1h, and the molar ratio of effective components in the resulting mixture is 25SiO2:Al2O3:3.85Na2O:2.12TMAdaOH:1692H2O.

[0070] (4) The mixture obtained in step (3) is transferred to a stainless steel reactor with a polytetrafluoroethylene liner for hydrothermal crystallization at a temperature of 170°C for 72 hours.

[0071] (5) The crystallized product was collected by filtration, washing (washing until the product pH was 9) and drying. The drying temperature was 75℃ and the drying time was 24h to obtain SSZ-13 molecular sieve product, which was denoted as product A3.

[0072] Perform XRD testing on product A3. Figure 1 The XRD test results of product A3 correspond to curve A3 in the middle curve. It can be seen that curve A3 is consistent with the standard spectrum and is a pure phase.

[0073] SEM electron microscopy was performed on product A3, and the results are as follows: Figure 2 A3 in the sample shows that the product has a crystalline morphology.

[0074] Example 4

[0075] The steps for preparing SSZ-13 molecular sieve using industrial perlite waste as raw material are as follows:

[0076] (1) Add 0.747g of TMAdaOH aqueous solution (mass fraction of 25%) and 0.071g of sodium hydroxide to 5.9mL of water and stir until homogeneous.

[0077] (2) After the solution obtained in step (1) has cooled to room temperature, add 0.174g of industrial perlite waste and stir for 3h.

[0078] (3) Add 0.709g of silica sol (SiO2 mass fraction of 30%) to the suspension obtained in step (2), stir evenly at room temperature for 1h, and the molar ratio of effective components in the resulting mixture is 25SiO2:Al2O3:3.85Na2O:3.85TMAdaOH:1692H2O.

[0079] (4) The mixture obtained in step (3) is transferred to a stainless steel reactor with a polytetrafluoroethylene liner, and the crystallization temperature is 170°C and the crystallization time is 72h.

[0080] (5) The crystallized product was collected by filtration, washing (washing until the product pH was 9) and drying. The drying temperature was 75℃ and the drying time was 24h to obtain SSZ-13 molecular sieve product, which was denoted as product A4.

[0081] Perform XRD testing on product A4. Figure 1 The XRD test results of product A4 correspond to curve A4 in the middle curve. It can be seen that curve A4 is consistent with the standard spectrum and is a pure phase.

[0082] SEM electron microscopy was performed on product A4, and the results are as follows: Figure 2 A4 in the sample shows that the product has a crystalline morphology.

[0083] Example 5

[0084] The steps for preparing SSZ-13 molecular sieve using industrial perlite waste as raw material are as follows:

[0085] (1) Add 0.523g of TMAdaOH aqueous solution (mass fraction of 25%) and 0.071g of sodium hydroxide to 6.3mL of water and stir until homogeneous.

[0086] (2) After the solution obtained in step (1) has cooled to room temperature, add 0.174g of industrial perlite waste and stir for 3h.

[0087] (3) Add 0.479g of silica sol (SiO2 mass fraction of 30%) to the suspension obtained in step (2), stir evenly at room temperature for 1h, and the molar ratio of effective components in the resulting mixture is 20SiO2:Al2O3:3.85Na2O:2.69TMAdaOH:1692H2O.

[0088] (4) The mixture obtained in step (3) is transferred to a stainless steel reactor with a polytetrafluoroethylene liner for hydrothermal crystallization at a temperature of 170°C for 72 hours.

[0089] (5) The crystallized product was collected by filtration, washing (washing until the product pH was 9) and drying. The drying temperature was 75℃ and the drying time was 24 hours to obtain SSZ-13 molecular sieve product, which was denoted as product A5.

[0090] XRD testing was performed on product A5. Figure 1The XRD test results of product A5 correspond to curve A5 in the middle curve. It can be seen that curve A5 is consistent with the standard spectrum and is a pure phase.

[0091] SEM electron microscopy was performed on product A5, and the results are as follows: Figure 2 A5 in the sample shows that the product has a crystalline morphology.

[0092] Comparative Example 1

[0093] (1) Add 0.358g of TMAdaOH aqueous solution (mass fraction of 25%) and 0.044g of sodium hydroxide to 5.1mL of water and stir until homogeneous.

[0094] (2) After the solution obtained in step (1) has cooled to room temperature, add 0.043g of sodium aluminate and stir for 3h.

[0095] (3) Add 1g of silica sol (SiO2 mass fraction of 30%) to the solution obtained in step (2), stir evenly at room temperature for 1h, and the effective component molar ratio in the resulting mixture is 25SiO2:Al2O3:3.85Na2O:2.12TMAdaOH:1692H2O.

[0096] (4) The mixture obtained in step (3) is transferred to a stainless steel reactor with a polytetrafluoroethylene liner for hydrothermal crystallization at a temperature of 170°C for 72 hours.

[0097] (5) The crystallized product was collected by filtration, washing (washing until the product pH was 9) and drying. The drying temperature was 75℃ and the drying time was 24h to obtain product B1.

[0098] XRD testing was performed on product B1. Figure 1 The curve B1 corresponds to the XRD test results of product B1, and it can be seen that curve B1 is an amorphous substance.

[0099] Comparative Example 2

[0100] (1) Add 0.358g of TMAdaOH aqueous solution (mass fraction of 25%) and 0.044g of sodium hydroxide to 5.4mL of water and stir until homogeneous.

[0101] (2) After the solution obtained in step (1) has cooled to room temperature, add 0.043g of sodium aluminate and stir for 3h.

[0102] (3) Add 0.75g of silica sol (AS-40) to the solution obtained in step (2), stir evenly at room temperature for 1h, and the molar ratio of effective components in the resulting mixture is 25SiO2:Al2O3:3.85Na2O:2.12TMAdaOH:1692H2O.

[0103] (4) The mixture obtained in step (3) is transferred to a stainless steel reactor with a polytetrafluoroethylene liner for hydrothermal crystallization at a temperature of 170°C for 72 hours.

[0104] (5) The crystallized product was collected by filtration, washing (washing until the product pH was 9) and drying. The drying temperature was 75℃ and the drying time was 24h to obtain product B2.

[0105] XRD testing was performed on product B2. Figure 1 The XRD test results of curve B2 correspond to product B2, showing that curve B2 is an amorphous substance.

[0106] Comparative Example 3

[0107] (1) Add 0.411g of TMAdaOH aqueous solution (mass fraction of 25%) and 0.071g of sodium hydroxide to 6.2mL of water and stir until homogeneous.

[0108] (2) After the solution obtained in step (1) has cooled to room temperature, add 0.174g of industrial perlite waste and stir for 3h.

[0109] (3) Add 0.709g of silica sol (SiO2 mass fraction of 30%) to the suspension obtained in step (2), stir evenly at room temperature for 1h, and the molar ratio of effective components in the resulting mixture is 25SiO2:Al2O3:3.85Na2O:2.12TMAdaOH:1692H2O.

[0110] (4) The mixture obtained in step (3) is transferred to a stainless steel reactor with a polytetrafluoroethylene liner for hydrothermal crystallization at a temperature of 120°C for 72 hours.

[0111] (5) The crystallized product was collected by filtration, washing (washing until the product pH was 9) and drying. The drying temperature was 75℃ and the drying time was 24h to obtain product B3.

[0112] XRD testing was performed on product B3. Figure 1 The XRD test results of curve B3 correspond to product B3, showing that curve B3 is an amorphous substance.

[0113] As can be seen from the above embodiments, this invention provides a simple method for synthesizing SSZ-13 molecular sieves using industrial perlite waste as raw material, achieving the first-ever preparation of SSZ-13 molecular sieves using industrial perlite waste as raw material. While ensuring product purity and crystallinity, the pretreatment step of industrial perlite waste is omitted, simplifying the process and reducing energy consumption. This invention realizes the resource utilization of industrial perlite waste, reduces the preparation cost of zeolite molecular sieves, and achieves the synthesis of highly crystalline zeolite molecular sieve materials.

[0114] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing SSZ-13 molecular sieve, characterized in that, Includes the following steps: A template agent, an alkali source, water, industrial perlite waste, and a silicon source are mixed to obtain a mixture; the alkali source is sodium hydroxide; the alkali source is calculated as Na2O, the industrial perlite waste is calculated as SiO2 and Al2O3, the silicon source is calculated as SiO2, and the molar ratio of SiO2, Al2O3, Na2O, template agent, and water in the mixture is (20~25):1:(2.31~3.85):(2.12~3.85):1692; the template agent is N,N,N-trimethyl-1-adamantyl ammonium hydroxide. The mixture was subjected to hydrothermal crystallization to obtain SSZ-13 molecular sieve; the hydrothermal crystallization temperature was 170℃.

2. The preparation method according to claim 1, characterized in that, The total mass content of SiO2 and Al2O3 in the industrial perlite waste is greater than 89%.

3. The preparation method according to claim 1, characterized in that, The silicon source includes silica sol.

4. The preparation method according to any one of claims 1 to 3, characterized in that, The mixing method is as follows: The template agent, alkali source and water are mixed in the first step to obtain a first mixture; The first mixture is mixed with industrial perlite waste to obtain a second mixture; The second mixture is then mixed with a silicon source in a third step to obtain the mixture.

5. The method according to claim 1, characterized in that, The molar ratio of SiO2, Al2O3, Na2O, template agent and water in the mixture is (20~25):1:(3.08~3.85):(2.69~3.85):1692.

6. The method according to claim 1, characterized in that, The hydrothermal crystallization time is 48~120h.

7. The method according to claim 1 or 6, characterized in that, The hydrothermal crystallization time is 72 hours.

8. The method according to claim 1, characterized in that, After hydrothermal crystallization, the process further includes sequentially performing solid-liquid separation, solid phase washing, and drying on the resulting crystallized liquid.

9. The method according to claim 1, characterized in that, The SSZ-13 molecular sieve has a crystalline morphology.

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