Process for the synthesis of large-particle beta molecular sieves

Abstract

The present disclosure relates to a method for synthesizing large-size beta molecular sieve, which comprises mixing an organic template agent, a silicon source, an aluminum source, water, an optional alkali source and an additive, and then performing crystallization to obtain beta molecular sieve; wherein the additive is an organic compound containing an ether bond and a hydroxyl group, the molar ratio of the additive to the silicon source is (0.05-0.5):1, and the silicon source is calculated as SiO2. The present disclosure adds an additive to the synthesis system without changing the original beta molecular sieve synthesis raw materials and ratio, so that the particle size of the synthesized beta molecular sieve is increased. The synthesis steps of the present disclosure are simple and easy to industrialize, the synthesized sample has good crystallinity, and can meet the requirements of different reactions for different particle sizes, thereby expanding the application range of beta molecular sieve.

Description

Technical Field

[0001] This disclosure relates to a method for synthesizing large-particle-size beta molecular sieves. Background Technology

[0002] Beta molecular sieves were first synthesized by Mobil in 1967 (US3,308,069) and possess a three-dimensional twelve-membered ring channel structure. Due to their unique topology and good thermal and hydrothermal stability, these molecular sieves exhibit excellent catalytic performance in reactions such as hydrocracking, hydroisomerization, hydrocarbon cracking, and alkylation, and are now in industrial production.

[0003] Beta molecular sieves can increase the yield of C4 and gasoline components in catalytic cracking reactions, but their thermal / hydrothermal stability is worse than that of ZSM-5 molecular sieves, and they are prone to rapid deactivation during the reaction, which restricts their application. It is generally believed that molecular sieves with larger crystal sizes are beneficial to enhancing their thermal / hydrothermal stability, and increasing the particle size of beta molecular sieves is also one of the methods to improve their hydrothermal stability. YJ Lee et al. (Journal of crystal growth, 2006, 297(1):138-145) synthesized beta molecular sieves with a silicon-to-aluminum ratio of about 50 in the system using tetraethylammonium bromide as a template agent. The crystal size can reach 1 μm, but the amount of template agent used is high (TEABr / SiO2=0.72), and the bromine-containing wastewater generated by the synthesis is difficult to treat, causing significant environmental pollution and making it unsuitable for industrial production. CN102923728 proposes a method for synthesizing large-grained β-zeolites, using precipitated silicon and pseudoboehmite as silicon and aluminum sources, respectively, adding tetraethylammonium hydroxide as a template agent, and tertiary alcoholamine as a chelating agent. The synthesized β-zeolite grain size can reach 0.1 to 3 μm. However, this method has high requirements for the silicon source, and the amount of template agent used is also too high (TEAOH / SiO2 = 0.30), and seed crystals need to be added during the synthesis process.

[0004] In recent years, some studies have attempted to introduce additives into the beta zeolite synthesis system to control the zeolite size. CN112939008A proposes introducing imidazole compounds into the beta zeolite synthesis system, achieving the goal of freely controlling the crystal size. However, this method has the drawback of requiring the addition of large amounts of imidazole compounds to increase the crystal size, significantly increasing the synthesis cost. Subsequent recovery and waste treatment are also troublesome, making it unsuitable for industrial operation. CN108298552A proposes introducing one or more of dimethyl carbonate, diethyl carbonate, or methyl ethyl carbonate into the beta zeolite synthesis system to increase the particle size of the beta zeolite. In practice, the gel needs to be pre-crystallized under negative pressure, making the method cumbersome, demanding, and unsuitable for industrial production. Summary of the Invention

[0005] The purpose of this disclosure is to provide a method for synthesizing beta molecular sieves that can increase the particle size of beta molecular sieves.

[0006] To achieve the above objectives, this disclosure provides a method for synthesizing large-particle-size beta molecular sieves, the method comprising:

[0007] An organic template agent, a silicon source, an aluminum source, water, an optional alkali source, and an additive are mixed and then crystallized to obtain a beta molecular sieve. The additive is an organic compound containing ether bonds and hydroxyl groups, and the molar ratio of the additive to the silicon source is (0.03-0.5):1, wherein the silicon source is SiO2.

[0008] Optionally, the additive has 3 to 50 carbon atoms, preferably 3 to 20, contains 1 to 20 ether bonds, preferably 1 to 5, and has 1 to 25 hydroxyl groups, preferably 1 to 5.

[0009] Optionally, the additive is one or more selected from ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol butyl ether, glycerol methyl ether, and 1,3-dimethoxy-2-propanol.

[0010] Optionally, the molar ratio of the additive to the silicon source is (0.05 to 0.2):1, and the silicon source is SiO2.

[0011] Optionally, the method further includes mixing the alkali source, the aluminum source, the organic template agent and the water, then adding the additive and the silicon source, and then performing the crystallization.

[0012] Optionally, the molar ratio of the silicon source to the aluminum source is (15-100):1, the molar ratio of the alkali source to the silicon source is (0-0.15):1, the molar ratio of the organic template agent to the silicon source is (0.08-0.3):1, and the molar ratio of water to the silicon source is (6-15):1, wherein the silicon source is calculated as SiO2, the aluminum source is calculated as Al2O3, and the alkali source is calculated as OH. - count.

[0013] Optionally, the organic template agent is one or more selected from tetraethylammonium hydroxide, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, and tetrapropylammonium hydroxide.

[0014] Optionally, the silicon source is silicone and / or aluminum silicate.

[0015] Optionally, the aluminum source is one or more selected from hydrated alumina, sodium aluminate, aluminum hydroxide, and silica-alumina gel.

[0016] Optionally, the alkali source is sodium hydroxide and / or potassium hydroxide.

[0017] Optionally, the crystallization conditions include: being carried out in a closed container at a temperature of 120–160°C for 36–84 hours.

[0018] Through the above technical solution, this disclosed method, without changing the original raw materials and proportions for beta molecular sieve synthesis, adds additives to the synthesis system, thereby increasing the particle size of the synthesized beta molecular sieve. This disclosed method has simple synthesis steps, is easy to industrialize, and produces samples with good crystallinity, meeting the requirements of different reactions for different particle sizes, thus expanding the application range of beta molecular sieves.

[0019] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0021] Figure 1 This is the XRD pattern of the beta molecular sieve prepared in Example 1.

[0022] Figure 2 This is an SEM image of the beta molecular sieve prepared in Example 1.

[0023] Figure 3 This is the XRD pattern of the beta molecular sieve prepared in Example 2.

[0024] Figure 4 This is an SEM image of the beta molecular sieve prepared in Example 2.

[0025] Figure 5 This is an SEM image of the beta molecular sieve prepared in Example 3.

[0026] Figure 6 This is an SEM image of the beta molecular sieve prepared in Example 4.

[0027] Figure 7 This is an SEM image of the beta molecular sieve prepared in Example 5.

[0028] Figure 8 This is the XRD pattern of the beta molecular sieve prepared in Comparative Example 1.

[0029] Figure 9 This is a SEM image of the beta molecular sieve prepared in Comparative Example 1. Detailed Implementation

[0030] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0031] This disclosure provides a method for synthesizing large-particle-size beta molecular sieves, the method comprising:

[0032] An organic template agent, a silicon source, an aluminum source, water, an optional alkali source, and an additive are mixed and then crystallized to obtain a beta molecular sieve. The additive is an organic compound containing ether bonds and hydroxyl groups, and the molar ratio of the additive to the silicon source is (0.03-0.5):1, wherein the silicon source is SiO2.

[0033] This disclosure provides a method to increase the crystal size of beta molecular sieves based on existing industrial synthesis technology, thereby meeting the requirements of different reactions for different particle sizes and expanding the application range of beta molecular sieves.

[0034] The inventors of this disclosure have discovered that adding organic compounds containing ether bonds and hydroxyl groups as additives to the synthesis system of beta molecular sieves can effectively increase the crystal size of beta molecular sieves. This method is low-cost, simple in process, and easy to industrialize.

[0035] According to this disclosure, the additive is a water-soluble organic compound with the following general formula: R1OR2OHR3, wherein R1, R2, and R3 can be substituted or unsubstituted alkyl or alkoxy groups, and the substituent can be a hydroxyl group. Further, the additive has 3 to 50 carbon atoms, preferably 3 to 20, contains 1 to 20 ether bonds, preferably 1 to 5, and has 1 to 25 hydroxyl groups, preferably 1 to 5. In a preferred embodiment of this disclosure, R2 is a group containing two carbon atoms. For example, the additive can be selected from ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol butyl ether, glycerol methyl ether, 1,3-dimethoxy-2-propanol, etc. Using the above-mentioned types of additives results in larger crystal sizes and better crystallinity in the synthesis of beta molecular sieves.

[0036] In a preferred embodiment of this disclosure, the molar ratio of the additive to the silicon source is (0.05–0.2):1, where the silicon source is SiO2. Using this additive ratio in the synthesis of beta molecular sieves is beneficial for further optimizing the grain size and crystallinity of the product.

[0037] In this method, the alkali source, organic template agent, silicon source, aluminum source, water, and additives can be mixed uniformly using conventional methods, and then the resulting mixture is subjected to crystallization. In a preferred embodiment of this disclosure, the method may further include mixing the alkali source, aluminum source, organic template agent, and water first, then adding the additives and silicon source, and then performing crystallization. By adjusting the order of adding the raw materials, it is beneficial to further optimize the grain size and crystallinity of the product.

[0038] In the synthesis system, the amounts of each raw material, except for the additives, can be the common proportions used in the synthesis of beta molecular sieves. According to a specific embodiment of this disclosure, the molar ratio of the silicon source to the aluminum source can be (15-100):1, preferably (20-35):1; the molar ratio of the alkali source to the silicon source can be (0-0.15):1, preferably (0.05-0.12):1; the molar ratio of the organic template agent to the silicon source can be (0.08-0.3):1, preferably (0.09-0.2):1; the molar ratio of water to the silicon source can be (6-15):1, preferably (7-10):1; wherein the silicon source is SiO2, the aluminum source is Al2O3, and the alkali source is OH... - count.

[0039] According to this disclosure, the organic template agent can be any organic template agent commonly used in the synthesis of beta molecular sieves that is well known to those skilled in the art. Preferably, the organic template agent is one or more selected from tetraethylammonium hydroxide, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, and tetrapropylammonium hydroxide.

[0040] The silicon source can be any silicon source commonly used in the synthesis of beta molecular sieves that is well known to those skilled in the art, and this disclosure does not impose any particular limitations on it. Preferably, the silicon source is silica gel and / or aluminosilicate gel, and the particle size of the silica gel and / or aluminosilicate gel is not particularly limited, for example, 150-250 μm.

[0041] The aluminum source can be any substance commonly used in the art that provides aluminum. Preferably, the aluminum source is one or more selected from hydrated alumina, sodium aluminate, aluminum hydroxide, and aluminosilicate gel. The hydrated alumina is alumina containing water of crystallization, such as boehmite, diaspore, gibbsite, boehmite, and pseudoboehmite. The particle size of the aluminosilicate gel is not particularly limited, for example, it can be 150–250 μm.

[0042] The alkali source can be any inorganic alkaline substance commonly used in the art, and its type is not particularly limited. Preferably, the alkali source is sodium hydroxide and / or potassium hydroxide.

[0043] The water can be the water commonly used in the synthesis of molecular sieves. In order to avoid the introduction of heteroatoms, deionized water is preferred in this disclosure.

[0044] According to this disclosure, the crystallization conditions can be the common crystallization conditions for synthesizing beta molecular sieves. In one specific embodiment of this disclosure, the crystallization conditions may include: carrying out the crystallization in a closed container at a temperature of 120–160°C for 36–84 hours. Preferred crystallization conditions involve a two-stage crystallization process: a first stage at 120–130°C for 12–24 hours, and a second stage at 140–155°C for 40–60 hours.

[0045] After crystallization is completed, beta molecular sieves can be recovered using common methods in the art. For example, the crystallized product can be washed with water, filtered, and dried to obtain beta molecular sieves. The drying conditions can be, for example, a temperature of 70–100°C and a time of 12–24 hours.

[0046] Compared with traditional beta molecular sieve synthesis technology, the beta molecular sieve synthesized by the present disclosure has a larger crystal size, for example, the average particle size can be 150 nm to 2 μm. Compared with the synthesis method without additives, the crystal size of beta molecular sieve can be increased by more than 25%.

[0047] The present disclosure will be further disclosed below through examples, but this does not limit the content of the present disclosure.

[0048] In the following examples and comparative examples, the crystal phase diagrams obtained by X-ray diffraction (XRD) were determined using a Philips Panalytical X'pert instrument. The test conditions were: Cu target, Kα radiation, Ni filter, high-energy detector, tube voltage 30 kV, and tube current 40 mA. The crystallinity of the industrial sample Beta30 from Hunan Changling Catalyst Co., Ltd. of China Petroleum & Chemical Corporation was 100%. The specific surface area was obtained by BET fitting of the adsorption curves in the range of P / P0 = 0.05 to 0.35 after obtaining the static N2 adsorption-desorption curves of the samples at liquid nitrogen temperature (77.4 K) using a Micromeritics ASAP2405J static adsorption instrument. The pore volume was determined according to the method described in RIPP151-90 of "Analytical Methods in Petrochemical Industry" compiled by Yang Cuiding et al. Scanning electron microscope (SEM) images were obtained using a FEI Quanta200F scanning electron microscope.

[0049] Example 1

[0050] Sodium aluminate solution (sodium oxide 287 g / L, aluminum oxide 159.7 g / L) and tetraethylammonium hydroxide (TEAOH, 2.417 mol / L, Guangzhou Dayou Fine Chemical Co., Ltd.) were added to deionized water and mixed thoroughly. Ethylene glycol ethyl ether was added as an additive. Coarse-porous silica gel (150–250 μm, 500 μm) was then added. 2 (0.9 mL / g, Shandong Yiming Industry & Trade Co., Ltd.) was mixed with the above liquid. The molar ratio of each component in the synthesis system was: SiO2 / Al2O3 = 28, NaOH / SiO2 = 0.10, TEAOH / SiO2 = 0.12, H2O / SiO2 = 7.0, ethylene glycol ethyl ether / SiO2 = 0.10. After stirring evenly, the obtained beta molecular sieve precursor was transferred to a pressure-resistant stainless steel reactor. Under stirring conditions, it was heated to 120℃ and crystallized under autogenous pressure for 24 hours, and then crystallized at 145℃ for 48 hours. After the stainless steel pressure-resistant reactor cooled to room temperature, the solid product was separated, washed, and dried at 80℃ for 24 hours to obtain the beta molecular sieve.

[0051] The XRD pattern of the beta molecular sieve prepared in this embodiment is shown in the figure. Figure 1 (Exhibits characteristic diffraction peaks of β-zeolite), SEM image see Figure 2 The physical and chemical parameters of the product are shown in Table 1.

[0052] Example 2

[0053] Beta molecular sieves were synthesized according to the method of Example 1, except that ethylene glycol methyl ether was used instead of ethylene glycol ethyl ether in Example 1. The molar ratios of the components in the synthesis system were as follows: SiO2 / Al2O3 = 25, NaOH / SiO2 = 0.12, TEAOH / SiO2 = 0.12, H2O / SiO2 = 6.5, and ethylene glycol methyl ether / SiO2 = 0.10.

[0054] The XRD pattern of the beta molecular sieve prepared in this embodiment is shown in the figure. Figure 3 (Exhibits characteristic diffraction peaks of β-zeolite), SEM image see Figure 4 The physical and chemical parameters of the product are shown in Table 1.

[0055] Example 3

[0056] Sodium aluminate solution (sodium oxide 287 g / L, aluminum oxide 159.7 g / L) and tetraethylammonium hydroxide (TEAOH, 2.417 mol / L, Guangzhou Dayou Fine Chemical Co., Ltd.) were added to deionized water and mixed thoroughly. Then, 1,3-dimethoxy-2-propanol was added, followed by coarse-porous silica gel (150–250 μm, 500 μm). 2(0.9 mL / g, Shandong Yiming Industry and Trade Co., Ltd.) Boehmite was added to the suspension. The molar ratios of the components in the synthesis system were: SiO2 / Al2O3 = 25, NaOH / SiO2 = 0.12, TEAOH / SiO2 = 0.10, H2O / SiO2 = 7.0, 1,3-dimethoxy-2-propanol / SiO2 = 0.10. The obtained beta molecular sieve precursor was transferred to a pressure-resistant stainless steel reactor. Under stirring, it was heated to 125℃ and crystallized under autogenous pressure for 24 hours, then crystallized at 145℃ for 48 hours. After the stainless steel pressure-resistant reactor cooled to room temperature, the solid product was separated, washed, and dried at 80℃ for 24 hours to obtain the beta molecular sieve.

[0057] The SEM image of the beta molecular sieve prepared in this embodiment is shown below. Figure 5 The physical and chemical parameters of the product are shown in Table 1.

[0058] Example 4

[0059] Sodium aluminate solution (sodium oxide 287 g / L, aluminum oxide 159.7 g / L) and tetraethylammonium hydroxide (TEAOH, 2.417 mol / L, Guangzhou Dayou Fine Chemical Co., Ltd.) were added to deionized water and mixed thoroughly. Ethylene glycol ethyl ether was then added, followed by the addition of coarse-porous silica gel (150–250 μm, 500 μm). 2 (0.9 mL / g, Shandong Yiming Industry & Trade Co., Ltd.) was added to the solution, followed by the addition of boehmite. The mixture was stirred and mixed thoroughly. The molar ratios of the components in the synthesis system were: SiO2 / Al2O3 = 25, NaOH / SiO2 = 0.12, TEAOH / SiO2 = 0.10, H2O / SiO2 = 7.5, and ethylene glycol ethyl ether / SiO2 = 0.15. The obtained beta molecular sieve precursor was transferred to a pressure-resistant stainless steel reactor. Under stirring, the mixture was heated to 120°C and crystallized under autogenous pressure for 24 hours, followed by crystallization at 145°C for 48 hours. After the stainless steel pressure-resistant reactor cooled to room temperature, the solid product was separated, washed, and dried at 80°C for 24 hours to obtain the beta molecular sieve.

[0060] The SEM image of the beta molecular sieve prepared in this embodiment is shown below. Figure 6 The physical and chemical parameters of the product are shown in Table 1.

[0061] Example 5

[0062] Beta molecular sieves were synthesized according to the method in Example 4, except that the molar ratios of the components in the synthesis system were: SiO2 / Al2O3 = 25, NaOH / SiO2 = 0.12, TEAOH / SiO2 = 0.10, H2O / SiO2 = 7.5, and ethylene glycol ethyl ether / SiO2 = 0.03.

[0063] SEM images of the beta molecular sieve prepared in this embodiment are shown below. Figure 7 The physical and chemical parameters of the product are shown in Table 1.

[0064] Example 6

[0065] Beta molecular sieves were synthesized according to the method in Example 4, except that the molar ratios of the components in the synthesis system were: SiO2 / Al2O3 = 25, NaOH / SiO2 = 0.12, TEAOH / SiO2 = 0.10, H2O / SiO2 = 7.5, and ethylene glycol ethyl ether / SiO2 = 0.5.

[0066] The physicochemical parameters of the beta molecular sieve prepared in this embodiment are shown in Table 1.

[0067] Comparative Example 1

[0068] Sodium aluminate solution (sodium oxide 145.8 g / L, aluminum oxide 102.8 g / L) and tetraethylammonium hydroxide (TEAOH, 2.417 mol / L, Guangzhou Dayou Fine Chemical Co., Ltd.) were added to deionized water, heated to dissolve, and stirred until homogeneous to prepare the working solution. Coarse-porous silica gel (150–250 μm, 500 μm) was then added. 2 The silica gel (0.9 ml / g, Qingdao Marine Chemical Plant) was mixed with the above working solution to wet the silica gel surface, resulting in a reaction mixture. The molar ratios of the components in the synthesis system were: SiO2 / Al2O3 = 28, NaOH / SiO2 = 0.10, TEAOH / SiO2 = 0.12, H2O / SiO2 = 7.0. The reaction mixture was crystallized in a high-pressure reactor at 120°C for 24 hours, then at 140°C for 48 hours. After cooling to room temperature, the solid product was separated, washed, and dried at 80°C for 24 hours to obtain the beta molecular sieve.

[0069] The XRD pattern of the beta molecular sieve prepared in this comparative example is shown below. Figure 8 (Exhibits characteristic diffraction peaks of β-zeolite), SEM image see Figure 9 The product's physical and chemical parameters are shown in Table 1.

[0070] Comparative Example 2

[0071] This comparative example synthesizes beta molecular sieves according to the method provided in CN103073018A, specifically as follows:

[0072] Apply silica-alumina paste (300-450μm, 415μm) 2(0.749 ml / g) and tetraethylammonium hydroxide (TEAOH, 2.417 mol / g, Guangzhou Dayou Fine Chemical Co., Ltd.) were added to deionized water, heated to dissolve, and stirred until homogeneous to prepare a working solution, which was then used to wet the surface of the solid particles. The molar ratio of each component in the synthesis system was SiO2 / Al2O3 = 25, TEAOH / SiO2 = 0.12, and H2O / SiO2 = 6.5. The reaction mixture was crystallized in a high-pressure reactor at 120°C for 24 hours, and then at 145°C for 48 hours. After cooling to room temperature, the solid product was separated, washed, and dried at 110°C to obtain beta molecular sieve.

[0073] The physicochemical parameters of the beta molecular sieve prepared in this comparative example are shown in Table 1.

[0074] Comparative Example 3

[0075] Sodium aluminate solution (sodium oxide 287 g / L, aluminum oxide 159.7 g / L) and tetraethylammonium hydroxide (TEAOH, 2.417 mol / L, Guangzhou Dayou Fine Chemical Co., Ltd.) were added to deionized water and mixed thoroughly. Coarse-porous silica gel (150–250 μm, 500 μm) was then added. 2 (0.9 mL / g, Shandong Yiming Industry & Trade Co., Ltd.) was mixed with the above liquid, and the molar ratio of each component in the synthesis system was SiO2 / Al2O3 = 25, NaOH / SiO2 = 0.12, TEAOH / SiO2 = 0.10, H2O / SiO2 = 6.5. After stirring evenly, the obtained beta molecular sieve precursor was transferred to a pressure-resistant stainless steel reactor. Under stirring conditions, it was heated to 120℃ and crystallized under autogenous pressure for 24 hours, and then crystallized at 145℃ for 48 hours. After the stainless steel pressure-resistant reactor cooled to room temperature, the solid product was separated, washed, and dried at 80℃ for 24 hours to obtain the beta molecular sieve.

[0076] The physicochemical parameters of the beta molecular sieve prepared in this comparative example are shown in Table 1.

[0077] Table 1

[0078]

[0079] As can be seen from the data in Table 1, the crystallinity, specific surface area and total pore volume of the beta molecular sieve synthesized according to the technical solution of this disclosure are basically the same as those of the beta molecular sieve synthesized by existing conventional methods, but the average particle size can reach more than 150 nm, while the particle size of the beta molecular sieve synthesized by the method without additives is less than 120 nm.

[0080] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0081] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0082] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A method for synthesizing large-particle-size beta molecular sieves, characterized in that, The method includes: An organic template agent, a silicon source, an aluminum source, water, an optional alkali source, and an additive are mixed and then crystallized to obtain a beta molecular sieve. The additive is an organic compound containing ether bonds and hydroxyl groups. The additive has 3 to 20 carbon atoms, 1 to 5 ether bonds, and 1 to 5 hydroxyl groups. The molar ratio of the additive to the silicon source is (0.03 to 0.5):

1. The silicon source is SiO2.

2. The method according to claim 1, wherein, The additive is selected from one or more of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol butyl ether, glycerol methyl ether, and 1,3-dimethoxy-2-propanol.

3. The method according to claim 1, wherein, The molar ratio of the additive to the silicon source is (0.05~0.2):1, and the silicon source is SiO2.

4. The method according to claim 1, wherein, The method further includes first mixing the alkali source, the aluminum source, the organic template agent and the water, then adding the additive and the silicon source, and then performing the crystallization.

5. The method according to claim 1, wherein, The molar ratio of the silicon source to the aluminum source is (15~100):1, the molar ratio of the alkali source to the silicon source is (0~0.15):1, the molar ratio of the organic template agent to the silicon source is (0.08~0.3):1, and the molar ratio of water to the silicon source is (6~15):1, wherein the silicon source is calculated as SiO2, the aluminum source is calculated as Al2O3, and the alkali source is calculated as OH. - count.

6. The method according to claim 1, wherein, The organic template agent is selected from one or more of tetraethylammonium hydroxide, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, and tetrapropylammonium hydroxide.

7. The method according to claim 1, wherein, The silicon source is silicone and / or aluminum silicate.

8. The method according to claim 1, wherein, The aluminum source is selected from one or more of hydrated alumina, sodium aluminate, aluminum hydroxide, and aluminosilicate gel. The alkaline source is sodium aluminate, sodium hydroxide, and / or potassium hydroxide.

9. The method according to claim 1, wherein, The crystallization conditions include: being carried out in a closed container at a temperature of 120~160℃ for 36~84h.

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