Sheet-like zsm-22 molecular sieve, method of making and use thereof

Abstract

The application relates to the technical field of molecular sieve preparation, and discloses a flaky ZSM-22 molecular sieve, a preparation method and application thereof, the method comprises the following steps: mixing a silicon source with water, stirring and hydrolyzing to obtain a pretreated silicon source; mixing the pretreated silicon source with an organic template agent, an aluminum source and water, adjusting the pH value of the mixed system to 11-14 to obtain a first suspension; mixing the first suspension with a potassium source to obtain a second suspension; heating the second suspension to perform a crystallization reaction, and then separating solid substances in a reaction product; the potassium source is selected from at least one of potassium chloride, potassium nitrate and potassium sulfate; and the molar ratio of the first suspension to the potassium source is 1:0.01-0.2 in terms of SiO2. The flaky ZSM-22 molecular sieve prepared by the application has a special flaky structure, the thickness of the nanosheet is less than 10 nm, and the nanosheet is dispersed and not stacked; and a catalyst prepared by using the molecular sieve has higher catalyst activity and a longer service life.

Description

Technical Field

[0001] This invention relates to the field of molecular sieve preparation technology, specifically to a sheet-like ZSM-22 molecular sieve, its preparation method, and its application. Background Technology

[0002] ZSM-22 molecular sieve is a microporous, high-silica molecular sieve developed by Mobile Industries, Inc. in the late 1980s. Its framework includes five-, six-, and ten-membered ring structures, belonging to a topological structure with only one-dimensional channels open by ten-membered rings. Due to its unique pore structure, ZSM-22 exhibits good selectivity in alkane isomerization reactions. Compared to other ten-membered ring molecular sieves (such as ZSM-5, ZSM-22, and ZSM-35), ZSM-22 has smaller pore diameters, and its advantages in adsorption reaction mechanisms make it an excellent catalyst for framework isomerization reactions. This unique pore structure, moderate surface acidity, excellent catalytic activity, and selectivity also give it strong catalytic performance in the isomerization of straight-chain hydrocarbons, such as catalytic dewaxing.

[0003] Conventionally synthesized ZSM-22 molecular sieves have relatively large crystal sizes. To further reduce the crystal size, Chinese patent application CN201610119519.0 discloses a method for synthesizing small-crystal ZSM-22 molecular sieves. Adding activated carbon, graphite, and carbon black to the synthesis system yields ZSM-22 molecular sieves with crystal lengths of approximately 100 nm. Chinese patent application CN201610176326.9 discloses a method for synthesizing sheet-like ZSM-22 molecular sieves. By changing the composition of the raw materials in the synthesis system, ZSM-22 molecular sieves with crystal lengths ranging from 150 to 800 nm can be obtained. Chinese patent applications CN201610222568.7 and CN201510084713.5 disclose a method for synthesizing ZSM-22 molecular sieve nanosheets.

[0004] Among them, Chinese patent application CN201610119519.0 discloses a method for synthesizing small-crystal ZSM-22 molecular sieves. During the ZSM-22 synthesis process, substances such as graphene, starch microspheres, chitosan, polylactic acid microspheres, activated carbon, carbon black, and graphite, which are easily adsorbed at the pore openings of the ZSM-22 molecular sieve, are added to inhibit ZSM-22 crystal growth and obtain small-crystal molecular sieves. This molecular sieve exhibits an isomerization selectivity of 75.1% on Pt / ZSM-22 small-crystal molecular sieves when the dodecane conversion rate is 90%. Chinese patent application CN201711329703.9 discloses a special morphology HSZM-22 molecular sieve, its preparation method, and its application. During the ZSM-22 synthesis process, a surfactant is added, and a special morphology HZSM-22 molecular sieve is prepared through a two-step crystallization process. This sieve is used in the isomerization alkaneization reaction of Fischer-Tropsch synthesis of middle distillate oils, achieving a selectivity of 92% for isoalkanes in the product. However, the catalytic activity and service life of catalysts prepared from ZSM-22 molecular sieves still need to be further improved. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems existing in the prior art and provide a sheet-like ZSM-22 molecular sieve, its preparation method and application. The sheet-like ZSM-22 molecular sieve prepared by this method has a special morphology, and the catalyst prepared using this molecular sieve has higher catalytic activity and longer service life.

[0006] To achieve the above objectives, the present invention provides a method for preparing sheet-like ZSM-22 molecular sieves, the method comprising the following steps: S1. Mix the silicon source with water, stir and hydrolyze to obtain a pretreated silicon source; S2. The pretreated silicon source is mixed with an organic template agent, an aluminum source and water, and the pH of the mixture is adjusted to 11-14 to obtain a first suspension. S3. Mix the first suspension with a potassium source to obtain a second suspension; S4. The second suspension is heated to carry out a crystallization reaction, and then the solid substances in the reaction product are separated. The potassium source is selected from at least one of potassium chloride, potassium nitrate, and potassium sulfate, and the first suspension is expressed as SiO2 and the potassium source is expressed as K. + The calculated molar ratio is 1:0.01~0.2.

[0007] Preferably, in step S1, the conditions for stirring and hydrolysis include: a rotation speed of 300~3000 rpm and a time of 1~24 h.

[0008] Preferably, in step S1, the mass ratio of the silicon source to the water is 1 to 10:1.

[0009] Preferably, in step S1, the silicon source is selected from at least one of water glass, sodium silicate crystals, tetraethyl orthosilicate, methyl orthosilicate, silica sol, and silica fume.

[0010] Preferably, in step S2, the molar ratio of the pretreated silicon source (SiO2), the aluminum source (Al2O3), the organic template agent, and the water is 1:(0.005~0.02):(0.1~0.4):(30~50).

[0011] Preferably, in step S2, the aluminum source is selected from at least one of boehmite, aluminum sulfate octahydrate, aluminum nitrate, and sodium aluminate.

[0012] Preferably, in step S2, the organic template agent is selected from at least one of diamine, ethylenediamine, n-butylamine, diethanolamine, octanediamine, pyridine ammonium salts, and imidazole ammonium salts.

[0013] Preferably, in step S2, the reagent used to adjust the pH of the mixture to 11-14 is selected from at least one of ammonia, nitric acid, hydrochloric acid, and carbonic acid.

[0014] Preferably, in step S3, the mixing conditions include: a stirring rate of 300~3000 rpm and a time of 1~24 h.

[0015] Preferably, in step S4, the conditions for the crystallization reaction include: a temperature of 120~180℃ and a time of 30~60h.

[0016] A second aspect of the present invention provides a sheet-like ZSM-22 molecular sieve prepared by the above-described method.

[0017] A third aspect of the present invention provides a method for preparing a molecular sieve catalyst, the method comprising the following steps: (1) Prepare sheet-like ZSM-22 molecular sieve according to the above method, then calcine the sheet-like ZSM-22 molecular sieve to remove the template agent, then mix the calcined product with ammonium chloride aqueous solution to carry out ion exchange, then separate the solid substances in the mixture, and calcine again to obtain H-ZSM-22 molecular sieve. (2) The H-ZSM-22 molecular sieve is mixed with boehmite and nitric acid solution, and then calcined to obtain the H-ZSM-22 molecular sieve support; (3) The H-ZSM-22 molecular sieve support is impregnated with a platinum source so that platinum is loaded in the H-ZSM-22 molecular sieve support, and then the impregnated product is dried and calcined.

[0018] Preferably, in step (2), the mass ratio of the H-ZSM-22 molecular sieve to the aluminum source is 7:3.

[0019] Preferably, in step (3), the platinum in the molecular sieve catalyst accounts for 0.5 wt% by mass.

[0020] The fourth aspect of the present invention provides the application of a molecular sieve catalyst prepared by the above method in the catalytic Fischer-Tropsch wax dewaxing reaction to produce lubricating oil base oil.

[0021] Through the above technical solution, the preparation method provided by this invention first pre-treats the silicon source by hydrolysis, then mixes it with an organic template agent, an aluminum source, and water, and adjusts the pH of the system to 11-14. Then, a potassium source is added and mixed before a crystallization reaction is carried out. By adjusting and improving the preparation process, and selecting a suitable potassium source and its addition ratio, the crystallization process is made more efficient by using K... + The electronic effect influences the bonding rate and crystallization direction of the raw materials, thereby controlling the morphology of the crystals. The ZSM-22 molecular sieve prepared in this way has a significantly different morphology from the needle-rod-shaped ZSM-22 molecular sieve prepared by the traditional hydrothermal method. It has a special plate-like structure with a thickness of less than 10 nm, and the nanosheets are dispersed and do not overlap. The catalyst prepared using this molecular sieve can significantly improve the diffusion performance of reactants and products in the molecular sieve channels, improve the effectiveness of the catalyst active sites, greatly improve its catalytic activity, effectively inhibit the occurrence of carbon deposition, and increase the service life of the catalyst. Attached Figure Description

[0022] Figure 1 This is the XRD pattern of the ZSM-22 molecular sieve prepared in Example 1; Figure 2 The XRD pattern of ZSM-22 molecular sieve prepared in Comparative Example 1 is shown. Figure 3 These are SEM images of the ZSM-22 molecular sieve prepared in Example 1; Figure 4-7 These are SEM images of ZSM-22 molecular sieves prepared in Comparative Examples 1-4. Detailed Implementation

[0023] The specific embodiments of the present invention 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 the present invention.

[0024] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0025] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating relative importance or implying the number of technical features indicated. Therefore, unless otherwise stated, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more. The term "comprising" and any variations thereof mean non-exclusive inclusion, where one or more other features, integers, steps, operations, units, components, and / or combinations thereof may be present or added.

[0026] In a first aspect, the present invention provides a method for preparing sheet-like ZSM-22 molecular sieves, the method comprising the following steps: S1. Mix the silicon source with water, stir and hydrolyze to obtain a pretreated silicon source; S2. The pretreated silicon source is mixed with an organic template agent, an aluminum source and water, and the pH of the mixture is adjusted to 11-14 to obtain a first suspension. S3. Mix the first suspension with a potassium source to obtain a second suspension; S4. The second suspension is heated to carry out a crystallization reaction, and then the solid substances in the reaction product are separated. The potassium source is selected from at least one of potassium chloride, potassium nitrate and potassium sulfate, and the molar ratio of the first suspension to the potassium source, calculated as SiO2, is 1:0.01~0.2.

[0027] In the preparation method provided by this invention, the silicon source is first pretreated by hydrolysis, then mixed with an organic template agent, an aluminum source, and water, and the pH of the system is adjusted to 11-14. A potassium source is then added and mixed before a crystallization reaction is carried out. Through adjustments and improvements to the preparation process, and by selecting a suitable potassium source and its addition ratio, the crystallization process is optimized using K... + The electronic effect of this invention influences the bonding rate and crystallization direction of the raw materials, thereby controlling the grain morphology. The ZSM-22 molecular sieve prepared in this way exhibits a significantly different morphology from the needle-like ZSM-22 molecular sieve prepared by the traditional hydrothermal method. It possesses a unique lamellar structure, with nanosheets less than 10 nm thick, dispersed, and without superposition. Catalysts prepared using this molecular sieve can significantly improve the diffusion performance of reactants and products within the molecular sieve channels, enhance the effectiveness of active sites, greatly improve catalytic activity, effectively inhibit carbon deposition, and increase catalyst lifespan. It can be used in the production of lubricating oil base oil from Fischer-Tropsch wax, improving the liquid yield and viscosity index of the base oil, and significantly reducing the pour point of the lubricating oil base oil. Furthermore, the preparation method provided by this invention is simple, reproducible, and easy to implement, suitable for industrial-scale production. The raw materials used are readily available and inexpensive.

[0028] In this invention, the potassium source is selected from at least one of potassium chloride, potassium nitrate, and potassium sulfate, and can be any one of the above substances, or any combination of two or three of them. Preferably, the potassium source is potassium chloride. Further, the molar ratio of the first suspension to the potassium source, calculated as SiO2, is 1:0.01~0.2, for example, it can be 1:0.01, 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.1, 1:0.11, 1:0.12, 1:0.13, 1:0.14, 1:0.15, 1:0.16, 1:0.17, 1:0.18, 1:0.19, or 1:0.2. In a preferred embodiment, the molar ratio of the first suspension to the potassium source, calculated as SiO2, is 1:0.06~0.14.

[0029] In this invention, the pH value of the mixing system is adjusted to 11-14 in step S2. For example, the pH value of the mixing system can be adjusted to 11, 11.5, 12, 12.5, 13, 13.5, or 14. In a preferred embodiment, the pH value of the mixing system is adjusted to 13.5-14 in step S2.

[0030] In some embodiments of the present invention, the conditions for the stirring hydrolysis in step S1 include: a rotation speed of 300~3000 rpm, for example, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm, 1000 rpm, 1500 rpm, 2000 rpm, 2500 rpm, or 3000 rpm; and a time of 1~24 h, for example, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 11 h, 12 h, 13 h, 14 h, 15 h, 16 h, 17 h, 18 h, 19 h, 20 h, 21 h, 22 h, 23 h, or 24 h. Furthermore, the stirring hydrolysis in step S1 can be carried out at room temperature, specifically at a room temperature of 10~35°C, more preferably at a room temperature of 25°C.

[0031] In some embodiments of the present invention, in step S1, the mass ratio of the silicon source to the water is 1 to 10:1, for example, it can be 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 or 10:1. Preferably, the mass ratio of the silicon source to the water is 1:1.

[0032] In some embodiments of the present invention, in step S1, the silicon source is selected from at least one of water glass, sodium silicate crystals, tetraethyl orthosilicate, methyl orthosilicate, silica sol, and silica fume. It can be any one of these substances, or any combination of two or more of them. Preferably, the silicon source is silica sol.

[0033] In some embodiments of the present invention, in step S2, the molar ratio of the pretreated silicon source (based on SiO2), the aluminum source (based on Al2O3), the organic template agent, and the water is 1:(0.005~0.02):(0.1~0.4):(30~50). The molar ratio of the pretreated silicon source (based on SiO2) to the aluminum source (based on Al2O3) can be, for example, 1:0.005, 1:0.006, 1:0.007, 1:0.008, 1:0.009, 1:0.01, 1:0.011, 1:0.012, 1:0.013, 1:0.014, 1:0.015, 1:0.016, 1:0.017, 1:0.018, 1:0.019, or 1:0.02, preferably. The molar ratio of the pretreated silicon source (SiO2) to the organic template agent can be, for example, 1:0.1, 1:0.15, 1:0.2, 1:0.25, 1:0.3, 1:0.35 or 1:0.4, preferably 1:0.2 to 0.25; the molar ratio of the pretreated silicon source (SiO2) to the water can be, for example, 1:30, 1:35, 1:40, 1:45 or 1:50, preferably 1:35 to 40.

[0034] In some embodiments of the present invention, in step S2, the aluminum source is selected from at least one of boehmite, aluminum sulfate octahydrate, aluminum nitrate, and sodium aluminate. It can be any one of these substances, or any combination of two or more of them. Preferably, the aluminum source is aluminum sulfate octahydrate or sodium aluminate.

[0035] In some embodiments of the present invention, in step S2, the organic template agent is selected from at least one of hexamethylenediamine, ethylenediamine, n-butylamine, diethanolamine, octanediamine, pyridine ammonium salts, and imidazole ammonium salts. It can be any one of the above substances, or any combination of two or more of them. Preferably, the organic template agent is hexamethylenediamine.

[0036] In some embodiments of the present invention, in step S2, the reagent used to adjust the pH of the mixture to 11-14 is selected from at least one of ammonia, nitric acid, hydrochloric acid, and carbonic acid. It can be any one of these substances, or any combination of two or more of them. Preferably, the reagent used to adjust the pH of the mixture in step S2 is ammonia.

[0037] In some embodiments of the present invention, the mixing conditions in step S3 include: a stirring rate of 300-3000 rpm, for example, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm, 1000 rpm, 1500 rpm, 2000 rpm, 2500 rpm, or 3000 rpm; and a time of 1-24 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, or 24 hours. Furthermore, the mixing in step S3 can be carried out at room temperature, specifically at a room temperature of 10-35°C, more preferably at a room temperature of 25°C.

[0038] In some embodiments of the present invention, the conditions for the crystallization reaction in step S4 include: a temperature of 120~180℃, for example, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, or 180℃; and a time of 30~60h, for example, 30h, 32h, 36h, 40h, 44h, 48h, 50h, 52h, 56h, or 60h. Furthermore, the crystallization reaction in step S4 can be carried out, for example, in a hydrothermal reactor. After the crystallization reaction is complete, solid-liquid separation can be achieved by filtration, vacuum filtration, or centrifugation to separate the solid substances in the reaction product. Then, the product is washed and dried to obtain the sheet-like ZSM-22 molecular sieve product.

[0039] In some specific embodiments of the present invention, the method for preparing sheet-like ZSM-22 molecular sieves specifically includes the following steps: S1. Mix silicon source with water at a mass ratio of 1 to 10:1, and hydrolyze at room temperature of 10 to 35°C with a stirring speed of 300 to 3000 rpm for 1 to 24 hours to obtain a pretreated silicon source, wherein the silicon source is selected from at least one of water glass, sodium silicate crystals, tetraethyl orthosilicate, methyl orthosilicate, silica sol and silica. S2. The pretreated silicon source is mixed with an organic template agent, an aluminum source, and water. The pretreated silicon source is calculated as SiO2, the aluminum source is calculated as Al2O3, and the molar ratio of the organic template agent and the water is 1:(0.005~0.02):(0.1~0.4):(30~50). At least one of ammonia, nitric acid, hydrochloric acid, and carbonic acid is used as an adjusting agent to adjust the pH of the mixed system to 11~14 to obtain a first suspension. The aluminum source is selected from at least one of boehmite, aluminum sulfate octahydrate, aluminum nitrate, and sodium aluminate. The organic template agent is selected from at least one of diamine, ethylenediamine, n-butylamine, diethanolamine, octyldiamine, pyridine ammonium salts, and imidazole ammonium salts. S3. The first suspension is mixed with a potassium source and stirred at 300-3000 rpm for 1-24 hours at room temperature of 10-35°C to obtain a second suspension. The potassium source is selected from at least one of potassium chloride, potassium nitrate and potassium sulfate. The molar ratio of the first suspension to the potassium source, calculated as SiO2, is 1:0.01-0.2. S4. The second suspension is transferred into a hydrothermal reactor and subjected to dynamic crystallization reaction at 120~180℃ for 30~60h. After the reaction is completed, the solid substances in the reaction product are separated, washed, and dried to obtain the sheet-like ZSM-22 molecular sieve raw powder.

[0040] Secondly, the present invention provides a sheet-like ZSM-22 molecular sieve prepared by the above-described method.

[0041] The ZSM-22 molecular sieve prepared by the method provided above in this invention has a significantly different morphology from the needle-rod-shaped ZSM-22 molecular sieve prepared by the traditional hydrothermal method. It has a special plate-like structure with nanosheets less than 10 nm thick, and they are dispersed and non-overlapping. The catalyst prepared using this molecular sieve can significantly improve the diffusion performance of reactants and products in the molecular sieve channels, improve the effectiveness of catalyst active sites, greatly enhance its catalytic activity, effectively inhibit the occurrence of carbon deposition, and increase the service life of the catalyst.

[0042] Thirdly, the present invention provides a method for preparing molecular sieve catalysts, the method comprising the following steps: (1) Prepare sheet-like ZSM-22 molecular sieve according to the method provided above, then calcine the sheet-like ZSM-22 molecular sieve to remove the template agent therein, then mix the calcined product with an ammonium chloride aqueous solution to carry out ion exchange, then separate the solid substances in the mixture, and calcine again to obtain H-ZSM-22 molecular sieve; (2) The H-ZSM-22 molecular sieve is mixed with boehmite and nitric acid solution, and then calcined to obtain the H-ZSM-22 molecular sieve support; (3) The H-ZSM-22 molecular sieve support is impregnated with a platinum source so that platinum is loaded in the H-ZSM-22 molecular sieve support, and then the impregnated product is dried and calcined.

[0043] The ZSM-22 molecular sieve is the ZSM-22 molecular sieve described above.

[0044] The method for preparing molecular sieve catalysts provided by this invention uses the plate-like ZSM-22 molecular sieve prepared by the above method. The prepared molecular sieve catalyst can significantly improve the diffusion performance of reactants and products in the molecular sieve channels, improve the effectiveness of catalyst active sites, greatly enhance its catalytic activity, effectively inhibit the occurrence of carbon deposition, and increase the service life of the catalyst.

[0045] In some embodiments of the present invention, the calcination conditions in step (1) include: a temperature of 400~500℃ and a time of 1~6h. In a preferred embodiment, the calcination conditions in step (1) are: a temperature of 450℃ and a time of 4h.

[0046] Further, in some embodiments of the present invention, step (1), the process of mixing the calcined product with an ammonium chloride aqueous solution for ion exchange and then separating the solid matter from the mixture specifically includes: mixing the calcined product with an ammonium chloride aqueous solution with a concentration of 0.5~2 mol / L (the mass ratio of the calcined product to the ammonium chloride aqueous solution is 1:8~12), performing ion exchange at a temperature of 75~85°C for 2~4 hours, then performing solid-liquid separation, and mixing the solid matter with the ammonium chloride solution again for ion exchange, repeating the aforementioned ion exchange process 3 times (a total of 4 times), and finally performing solid-liquid separation to obtain the solid matter. In a preferred embodiment, the ion exchange conditions include: a temperature of 80°C and a time of 3 hours.

[0047] Furthermore, in some embodiments of the present invention, the conditions for re-calcination in step (1) include: a temperature of 500~600℃ and a time of 8~12h. In a preferred embodiment, the conditions for re-calcination in step (1) are: a temperature of 550℃ and a time of 10h.

[0048] In some embodiments of the present invention, in step (2), the mass ratio of the H-ZSM-22 molecular sieve to the pseudoboehmite is 1 to 10:1, for example, it can be 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 or 10:1. In a preferred case, the mass ratio of the H-ZSM-22 molecular sieve to the pseudoboehmite is 7:3. Further, in some embodiments of the present invention, in step (2), the pseudoboehmite is preferably SB powder, that is, high-purity pseudoboehmite powder.

[0049] In some embodiments of the present invention, in step (2), the total mass ratio of the H-ZSM-22 molecular sieve and the pseudoboehmite to the nitric acid solution is 1:0.1~0.6, for example, it can be 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5 or 1:0.6. Further, in some embodiments of the present invention, in step (2), the concentration of the nitric acid solution is 2~5 wt%.

[0050] Furthermore, in some embodiments of the present invention, the calcination conditions in step (2) include: a temperature of 500~600℃ and a time of 3~5h. In a preferred embodiment, the conditions for the second calcination in step (2) are: a temperature of 550℃ and a time of 4h.

[0051] In some embodiments of the present invention, in step (3), the platinum in the molecular sieve catalyst has a mass ratio of 0.1% to 1%, for example, it can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%. Preferably, the platinum in the molecular sieve catalyst has a mass ratio of 0.5%. Further, in some embodiments of the present invention, in step (3), the platinum source is an aqueous solution of chloroplatinic acid. Even further, in some embodiments of the present invention, in step (3), the impregnation conditions include: a temperature of 20-30°C and a time of 20-30 hours. Preferably, the impregnation conditions in step (3) include: a temperature of 25°C and a time of 24 hours.

[0052] In some embodiments of the present invention, the drying conditions in step (3) include: a temperature of 120~180°C and a time of 2~4 hours. In a preferred embodiment, the drying conditions in step (3) include: a temperature of 140°C and a time of 3 hours.

[0053] Furthermore, in some embodiments of the present invention, the calcination conditions in step (3) include: a temperature of 350~450℃ and a time of 3~5h. In a preferred embodiment, the calcination conditions in step (3) include: a temperature of 400℃ and a time of 4h.

[0054] In some embodiments of the present invention, the method for preparing the molecular sieve catalyst specifically includes the following steps: (1) Prepare sheet-like ZSM-22 molecular sieves using the method provided above in this invention, and then calcine the sheet-like ZSM-22 molecular sieves at 300~400℃ for 4~6h to remove the organic template agent therein. Then mix the calcined product with an ammonium chloride aqueous solution with a concentration of 0.5~2mol / L (the mass ratio of the calcined product to the ammonium chloride aqueous solution is 1:8~12), and perform ion exchange at 75~85℃ for 2~4h. Then separate the solid and liquid, and mix the solid material with the ammonium chloride solution again for ion exchange. Repeat the above ion exchange process 3 times (4 times in total). Finally, separate the solid and liquid and dry the obtained solid material. Then, calcine it again at 500~600℃ for 8~12h in an air atmosphere to obtain H-ZSM-22 molecular sieves. (2) The H-ZSM-22 molecular sieve and pseudoboehmite are mixed at a mass ratio of 1 to 10:1, and then a nitric acid solution (the concentration of the nitric acid solution is 2 to 5 wt%, and the mass ratio of the total mass of H-ZSM-22 molecular sieve and pseudoboehmite to the mass of the nitric acid solution is 1:0.1 to 0.6) is added to mix and bind them together. The mixture is then extruded into strips, and the resulting product is calcined in air at a temperature of 500 to 600°C for 3 to 5 hours to obtain the H-ZSM-22 molecular sieve carrier. (3) Mix the aqueous solution of chloroplatinic acid with the H-ZSM-22 molecular sieve support (the mass ratio of the aqueous solution of chloroplatinic acid to the H-ZSM-22 molecular sieve support, calculated as platinum, is 0.1~1:100), stir and impregnate at 20~30℃ for 20~30h, then dry the impregnated product at 100~120℃ for 2~4h, and then calcine at 350~450℃ for 3~5h to obtain the H-ZSM-22 molecular sieve catalyst with a platinum loading of 0.1~1wt%.

[0055] Fourthly, the present invention provides the application of a molecular sieve catalyst prepared by the above method in the catalytic Fischer-Tropsch wax dewaxing reaction to produce lubricating oil base oil.

[0056] When the H-ZSM-22 molecular sieve catalyst prepared by the method provided above in this invention is used in the production of lubricating oil base oil from Fischer-Tropsch synthetic wax, it can improve the liquid yield and viscosity index of the base oil and significantly reduce the pour point of the lubricating oil base oil.

[0057] The following examples further illustrate the sheet-like ZSM-22 molecular sieve, its preparation method, and its applications according to the present invention. The examples are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following examples.

[0058] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following embodiments are commercially available.

[0059] Example 1 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, aluminum sulfate octadecade and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade is calculated as Al2O3, and the molar ratio of 1,6-hexanediamine and water is 1:0.012:0.2:40), and then add ammonia to adjust the pH of the mixture to 13.5 to obtain the first suspension; (3) Add KCl to the first suspension prepared in step (2) (the first suspension is calculated as SiO2 and KCl is calculated as K). + The molar ratio was 1:0.12. The mixture was stirred at 1000 rpm for 2 hours at room temperature of 25°C to obtain the second suspension. (4) The second suspension prepared in step (3) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 48 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare sheet-like ZSM-22 molecular sieve.

[0060] Example 2 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, aluminum sulfate octadecade and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade is calculated as Al2O3, and the molar ratio of 1,6-hexanediamine and water is 1:0.011:0.21:40), and then add ammonia to adjust the pH of the mixture to 13.5 to obtain the first suspension; (3) Add KCl to the first suspension prepared in step (2) (the first suspension is calculated as SiO2 and KCl is calculated as K). + The molar ratio was 1:0.14. The mixture was stirred at 1000 rpm for 2 hours at room temperature of 25°C to obtain the second suspension. (4) The second suspension prepared in step (3) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 48 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare sheet-like ZSM-22 molecular sieve.

[0061] Example 3 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, sodium aluminate and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade is calculated as Al2O3, and the molar ratio of 1,6-hexanediamine and water is 1:0.011:0.2:35), and then add ammonia to adjust the pH of the mixture to 13 to obtain the first suspension; (3) Add KCl to the first suspension prepared in step (2) (the first suspension is calculated as SiO2 and KCl is calculated as K). + The molar ratio was 1:0.1. The mixture was stirred at 1000 rpm for 2 hours at room temperature of 25°C to obtain the second suspension. (4) The second suspension prepared in step (3) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 46 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare sheet-like ZSM-22 molecular sieve.

[0062] Example 4 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, aluminum sulfate octadecade and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade is calculated as Al2O3, and the molar ratio of 1,6-hexanediamine and water is 1:0.0125:0.22:40), and then add ammonia to adjust the pH of the mixture to 14 to obtain the first suspension; (3) Add KCl to the first suspension prepared in step (2) (the first suspension is calculated as SiO2 and KCl is calculated as K). + The molar ratio was 1:0.08. The mixture was stirred at 1000 rpm for 2 hours at room temperature of 25°C to obtain the second suspension. (4) The second suspension prepared in step (3) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 45 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare sheet-like ZSM-22 molecular sieve.

[0063] Example 5 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, aluminum sulfate octadecade and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade is calculated as Al2O3, and the molar ratio of 1,6-hexanediamine and water is 1:0.014:0.2:40), and then add ammonia to adjust the pH of the mixture to 14 to obtain the first suspension; (3) Add KCl to the first suspension prepared in step (2) (the first suspension is calculated as SiO2 and KCl is calculated as K). + The molar ratio was 1:0.06. The mixture was stirred at 1000 rpm for 2 hours at room temperature of 25°C to obtain the second suspension. (4) The second suspension prepared in step (3) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 48 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare sheet-like ZSM-22 molecular sieve.

[0064] Example 6 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, aluminum sulfate octadecade and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade is calculated as Al2O3, and the molar ratio of 1,6-hexanediamine and water is 1:0.01:0.25:40), and then add ammonia to adjust the pH of the mixture to 14 to obtain the first suspension; (3) Add KCl to the first suspension prepared in step (2) (the first suspension is calculated as SiO2 and KCl is calculated as K). + The molar ratio was 1:0.06. The mixture was stirred at 1000 rpm for 2 hours at room temperature of 25°C to obtain the second suspension. (4) The second suspension prepared in step (3) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 48 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare sheet-like ZSM-22 molecular sieve.

[0065] Example 7 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, aluminum sulfate octadecade and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade is calculated as Al2O3, and the molar ratio of 1,6-hexanediamine and water is 1:0.009:0.2:38), and then add ammonia to adjust the pH of the mixture to 13.5 to obtain the first suspension; (3) Add KCl to the first suspension prepared in step (2) (the first suspension is calculated as SiO2 and KCl is calculated as K). + The molar ratio was 1:0.06. The mixture was stirred at 1000 rpm for 2 hours at room temperature of 25°C to obtain the second suspension. (4) The second suspension prepared in step (3) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 48 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare sheet-like ZSM-22 molecular sieve.

[0066] Example 8 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, aluminum sulfate octadecade and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade is calculated as Al2O3, and the molar ratio of 1,6-hexanediamine and water is 1:0.008:0.22:40), and then add ammonia to adjust the pH of the mixture to 13.8 to obtain the first suspension; (3) Add KCl to the first suspension prepared in step (2) (the first suspension is calculated as SiO2 and KCl is calculated as K). + The molar ratio was 1:0.1. The mixture was stirred at 1000 rpm for 2 hours at room temperature of 25°C to obtain the second suspension. (4) The second suspension prepared in step (3) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 48 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare sheet-like ZSM-22 molecular sieve.

[0067] Example 9 ZSM-22 molecular sieves were prepared according to the method in Example 4, except that KCl in step (3) was replaced with KNO3, and the first suspension was prepared as SiO2 and KNO3 as K + The molar ratio is calculated to be 1:0.1.

[0068] Example 10 ZSM-22 molecular sieves were prepared according to the method in Example 4, except that KCl in step (3) was replaced with K2SO4, and the first suspension was prepared as SiO2 and K2SO4 as K + The molar ratio is calculated to be 1:0.1.

[0069] Comparative Example 1 (1) Mix silica sol and water at a mass ratio of 1:1, and stir at 1000 rpm for 2 hours at room temperature of 25°C to obtain silica sol aqueous solution. (2) Mix the silica sol aqueous solution prepared in step (1) with 1,6-hexanediamine, aluminum sulfate octadecade, KOH and water evenly (the silica sol aqueous solution is calculated as SiO2, aluminum sulfate octadecade as Al2O3, and 1,6-hexanediamine and KOH as K... + The molar ratio of water to water was 1:0.008:0.22:0.01:40, resulting in a suspension. (3) The suspension prepared in step (2) is transferred into a hydrothermal reactor and dynamically crystallized at 160°C for 48 hours. After crystallization, solid-liquid separation is performed, and then the solid material is washed and dried to prepare ZSM-22 molecular sieve.

[0070] Comparative Example 2 ZSM-22 molecular sieves were prepared according to the method of Comparative Example 1, except that KOH in step (2) was replaced with KCl, and the silica sol aqueous solution was calculated as SiO2 and KOH was calculated as KCl. + The molar ratio is calculated to be 1:0.3.

[0071] Comparative Example 3 ZSM-22 molecular sieves were prepared according to the method in Example 8, except that KCl in step (3) was replaced with KOH, and the first suspension was mixed with KOH in the form of SiO2. + The molar ratio was adjusted to 1:0.005.

[0072] Comparative Example 4 ZSM-22 molecular sieves were prepared according to the method in Example 8, except that KCl in step (3) was replaced with KOH, and the first suspension was mixed with KOH in the form of SiO2. + The molar ratio was adjusted to 1:0.3.

[0073] Application Example 1 (1) Take the ZSM-22 molecular sieve prepared in Example 1 and calcine it at 350°C for 5 hours to remove the organic template agent. Then, mix the calcined product with an ammonium chloride aqueous solution with a concentration of 1 mol / L (the mass ratio of the calcined product to the ammonium chloride aqueous solution is 1:10). Perform ion exchange at 80°C for 3 hours. Then, separate the solid and liquid and mix the solid with the ammonium chloride solution again for ion exchange. Repeat the above ion exchange process 3 times (4 times in total). Finally, separate the solid and liquid and dry the obtained solid. Then, calcine it again at 550°C for 10 hours in an air atmosphere to obtain H-ZSM-22 molecular sieve. (2) The H-ZSM-22 molecular sieve prepared in step (1) is mixed with SB powder (pseudoboehmite) at a mass ratio of 7:3, and then nitric acid solution (the concentration of nitric acid solution is 3wt%, and the mass ratio of the total mass of H-ZSM-22 molecular sieve and SB powder to the mass of nitric acid solution is 1:0.3) is added to mix and bind, extruded into strips, and then the resulting molded product is calcined at 550℃ for 4h in air atmosphere to obtain H-ZSM-22 molecular sieve carrier; (3) The aqueous solution of chloroplatinic acid was mixed with the H-ZSM-22 molecular sieve support prepared in step (2) (the mass ratio of the aqueous solution of chloroplatinic acid to the H-ZSM-22 molecular sieve support, calculated as platinum, was 1:0.3). The mixture was stirred and impregnated at 25°C for 24 h. The impregnated product was then dried at 110°C for 3 h and calcined at 400°C for 4 h to prepare an H-ZSM-22 molecular sieve catalyst with a platinum loading of 0.5 wt%.

[0074] Application Examples 2-10 The H-ZSM-22 molecular sieve catalyst was prepared according to the method of Application Example 1, except that the molecular sieve raw material in step (1) was replaced by the ZSM-22 molecular sieve prepared in Example 1 with the ZSM-22 molecular sieve prepared in Examples 2-10.

[0075] Application Comparative Examples 1-4 ZSM-22 molecular sieve catalysts were prepared according to the method of Application Example 1, except that the ZSM-22 molecular sieve prepared in Example 1 was replaced with the ZSM-22 molecular sieves prepared in Comparative Examples 1-4.

[0076] Application Example 11 The H-ZSM-22 molecular sieve catalyst prepared in Application Example 1 was crushed to 20-40 mesh. 100 mL of the molecular sieve catalyst was loaded into the isothermal zone of the reaction tube, and the molecular sieve catalyst in the reaction tube was supported by inert quartz sand. The Fischer-Tropsch synthesis wax was subjected to a catalytic dewaxing and pour point reduction reaction to prepare lubricating oil base oil. The reaction conditions included: hydrogen partial pressure of 3.0 MPa and volume hourly space velocity of 1 h⁻¹. -1The hydrogen-to-oil volume ratio is 500:1, and the reaction temperature is 350℃.

[0077] The chemical properties of the waxy feedstock are shown in Table 1 (in Table 1, IBP represents the initial boiling point and FBP represents the final boiling point). After the reaction, the pour point and viscosity index of the lubricating oil base oil products were determined, and the liquid yield was calculated. The results are shown in Table 2.

[0078] Application Examples 12-20 The lubricating oil base oil was prepared according to the method of Application Example 11, except that the molecular sieve catalyst raw material was replaced by the H-ZSM-22 molecular sieve catalyst prepared in Application Example 1 with the H-ZSM-22 molecular sieve catalyst prepared in Application Examples 2-10.

[0079] Application Comparison 5-8 The lubricating oil base oil was prepared according to the method of Application Example 11, except that the molecular sieve catalyst raw material was replaced by the H-ZSM-22 molecular sieve catalyst prepared in Application Example 1 with the H-ZSM-22 molecular sieve catalyst prepared in Comparative Examples 1-4.

[0080] Test case Performance tests were conducted on the above embodiments, comparative examples, application embodiments, and application comparative examples. The test methods and results are as follows: (1) XRD test XRD analysis was performed using Panaco X'pert3 powder from the Netherlands. The test conditions were: operating voltage 40 kV, tube current 40 mA, copper-palladium, 1D semiconductor PIXcel1D matrix detector, scanning mode: θ / θ, minimum step size: 0.0001. The samples to be tested were dried, ground, and pressed into tablets. The diffraction intensity (peak height) of the characteristic peaks of the standard and the samples to be tested (the sheet-like ZSM-22 molecular sieves prepared in Examples 1-10 and the ZSM-22 molecular sieves prepared in Comparative Examples 1-4) were measured using an X-ray diffractometer. The relative crystallinity RC of the samples to be tested was calculated as RC = (ΣIsample / ΣIstandard) × 100%.

[0081] The XRD test pattern shown here is only an example of Example 1, such as... Figure 1 As shown, the XRD patterns of the samples prepared in Examples 2-10 are similar to those in Example 1. The prepared ZSM-22 molecular sieve conforms to the standard molecular sieve spectrum of TON structure and no impurity phase appears. The relative crystallinity of the samples prepared in Examples 1-10 are 100%, 103%, 95%, 106%, 101%, 103%, 98%, 101%, 102% and 99%, respectively.

[0082] The XRD pattern of the sample prepared in Comparative Example 1 is shown below. Figure 2As shown, the XRD patterns of the samples prepared in Comparative Examples 2-4 are similar to those in Comparative Example 2. The prepared ZSM-22 molecular sieve conforms to the standard molecular sieve spectrum of TON structure and no impurity phase appears. The relative crystallinity of the samples prepared in Comparative Examples 1-4 is 97%, 88%, 91% and 93%, respectively.

[0083] (2) SEM test ZSM-22 molecular sieves prepared in Examples 1-10 and Comparative Examples 1-4 were used as samples by Phenom-Pro scanning electron microscopes from the Netherlands. The samples were thoroughly ground and then sputter-coated with gold. The accelerating voltage was 10 kV.

[0084] SEM images of the sample in Example 1 are shown below. Figure 3 As shown, the XRD patterns of the samples prepared in Examples 2-10 are similar to those in Example 1. The sample morphology is sheet-like, dispersed without superposition, and the thickness of the nanosheets is less than 10 nm.

[0085] SEM image of sample 1 (Comparative Example 1) is shown below. Figure 4 As shown, the sample morphology is rod-shaped; the SEM image of the sample prepared in Comparative Example 2 is shown below. Figure 5 As shown, similar to Comparative Example 1, the sample morphology is rod-shaped with a small amount of aggregation. The SEM image of the sample prepared in Comparative Example 3 is shown below. Figure 6 As shown, the morphology is rod-shaped with a small amount of aggregation; the SEM image of the sample prepared in Comparative Example 4 is shown below. Figure 7 As shown, the morphology is rod-shaped, and the aggregation phenomenon is obvious.

[0086] (3) Catalytic activity test The catalysts obtained in Application Examples 11-20 and Comparative Examples 5-8 were used respectively, with the whole fraction of Fischer-Tropsch synthetic wax (distillation range 360~750℃) as feedstock (performance parameters are shown in Table 1), for hydrodewaxing reaction. The reaction was carried out on a 100mL hydrotreating apparatus under the following conditions: hydrogen-to-oil ratio of 500:1, reaction pressure of 3MPa, and volumetric hourly space velocity of 1h⁻¹. -1 The reaction temperature was 350℃. After the reaction, the pour point and viscosity index of the lubricating oil base oil were measured, and the liquid yield was calculated. The results are shown in Table 2. The viscosity index was measured using an Anton Paar SMV3000 instrument from Austria, according to ASTM D2270 (GB / T 1995-1998); the pour point was measured using an HP850C instrument from Hellmann GmbH from Germany, according to GB / T 3535-2006; the liquid yield was calculated using the following formula: Liquid yield % = (Weight of liquid product at 350℃~FBP) / Weight of feedstock × 100%.

[0087] Table 1

[0088] Table 2

[0089] As can be seen from the results in Table 2, the H-ZSM-22 molecular sieve catalyst prepared by the method of the present invention has higher catalytic activity. When used in the Fischer-Tropsch wax depletion reaction to prepare lubricating oil base oil, it can improve the liquid yield and viscosity index of the lubricating oil base oil and reduce the pour point of the base oil.

[0090] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing sheet-like ZSM-22 molecular sieves, characterized in that, The method includes the following steps: S1. Mix the silicon source with water, stir and hydrolyze to obtain a pretreated silicon source; S2. The pretreated silicon source is mixed with an organic template agent, an aluminum source and water, and the pH of the mixture is adjusted to 11-14 to obtain a first suspension. S3. Mix the first suspension with a potassium source to obtain a second suspension; S4. The second suspension is heated to carry out a crystallization reaction, and then the solid substances in the reaction product are separated. The potassium source is selected from at least one of potassium chloride, potassium nitrate, and potassium sulfate, and the first suspension is expressed as SiO2 and the potassium source is expressed as K. + The calculated molar ratio is 1:0.01~0.

2.

2. The method according to claim 1, characterized in that, In step S1, the conditions for the stirring hydrolysis include: a rotation speed of 300~3000 rpm and a time of 1~24 h; and / or, In step S1, the mass ratio of the silicon source to the water is 1~10:1; and / or, In step S1, the silicon source is selected from at least one of water glass, sodium silicate crystals, tetraethyl orthosilicate, methyl orthosilicate, silica sol, and silica fume.

3. The method according to claim 1 or 2, characterized in that, In step S2, the molar ratio of the pretreated silicon source (based on SiO2), the aluminum source (based on Al2O3), the organic template agent, and the water is 1:(0.005~0.02):(0.1~0.4):(30~50); and / or, In step S2, the aluminum source is selected from at least one of boehmite, aluminum sulfate octahydrate, aluminum nitrate, and sodium aluminate; and / or, In step S2, the organic template agent is selected from at least one of diamine, ethylenediamine, n-butylamine, diethanolamine, octanediamine, pyridine ammonium salts, and imidazole ammonium salts.

4. The method according to any one of claims 1-3, characterized in that, In step S2, the reagent used to adjust the pH of the mixture to 11-14 is selected from at least one of ammonia, nitric acid, hydrochloric acid, and carbonic acid.

5. The method according to any one of claims 1-4, characterized in that, In step S3, the mixing conditions include: a stirring rate of 300~3000 rpm and a time of 1~24 h.

6. The method according to any one of claims 1-5, characterized in that, In step S4, the conditions for the crystallization reaction include: a temperature of 120~180℃ and a time of 30~60h.

7. The sheet-like ZSM-22 molecular sieve prepared by the method according to any one of claims 1-6.

8. A method for preparing molecular sieve catalysts, characterized in that, The method includes the following steps: (1) Prepare sheet-like ZSM-22 molecular sieve according to any one of claims 1-6, then calcine the sheet-like ZSM-22 molecular sieve to remove the template agent therein, then mix the calcined product with an ammonium chloride aqueous solution to perform ion exchange, then separate the solid substances in the mixture, and calcine again to obtain H-ZSM-22 molecular sieve; (2) The H-ZSM-22 molecular sieve is mixed with boehmite and nitric acid solution, and then calcined to obtain the H-ZSM-22 molecular sieve support; (3) The H-ZSM-22 molecular sieve support is impregnated with a platinum source so that platinum is loaded in the H-ZSM-22 molecular sieve support, and then the impregnated product is dried and calcined.

9. The method according to claim 8, characterized in that, In step (2), the mass ratio of the H-ZSM-22 molecular sieve to the aluminum source is 7:3; and / or, In step (3), the platinum in the molecular sieve catalyst accounts for 0.5 wt% by mass.

10. The application of the molecular sieve catalyst prepared by the method of claim 8 or 9 in the catalytic Fischer-Tropsch wax dewaxing reaction to produce lubricating oil base oil.

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