Molded SAPO-5 molecular sieve catalyst, preparation method and application thereof, and method for preparing p-tert-butyltoluene through isomerization of m-tert-butyltoluene

Abstract

The invention particularly relates to a formed SAPO-5 molecular sieve catalyst, a preparation method and application thereof and a method for preparing p-tert-butyltoluene through isomerization of m-tert-butyltoluene. An X-ray diffraction spectrum of the formed SAPO-5 molecular sieve catalyst conforms to a characteristic diffraction peak of a pure SAPO-5 molecular sieve; the 2theta value is that the ratio of the area of the three diffraction peaks at 19-25 degrees to the area sum of the three diffraction peaks corresponding to the pure SAPO-5 molecular sieve is 0.9-1.1. The formed SAPO-5 molecular sieve catalyst has relatively high reaction activity, can effectively improve the reactant conversion rate and the target product yield, has the advantages of simple process operation, low reaction cost and high product yield when being applied to a reaction for preparing p-tert-butyltoluene through isomerization of m-tert-butyltoluene, and is suitable for industrial production. Meanwhile, continuous production of p-tert-butyltoluene can be realized when the catalyst is used in a fixed bed reaction, and the catalyst has a good industrial application prospect.

Description

Technical Field

[0001] This invention relates to a shaped SAPO-5 molecular sieve catalyst, its preparation method and application, and a method for isomerizing m-tert-butyltoluene to prepare p-tert-butyltoluene. Background Technology

[0002] p-tert-butyltoluene (P-TBT) is a colorless and transparent liquid, a derivative of toluene, and can be used to prepare p-tert-butylbenzoic acid, p-tert-butylbenzyl chloride, p-tert-butylbenzaldehyde, methyl p-tert-butylbenzoate, p-tert-butylbenzonitrile, etc. P-tert-butyltoluene and its derivatives are also important raw materials in fine chemical products and electronic chemicals, and are widely used in metalworking fluids, lubricant additives, pharmaceuticals, pesticides, dyes and fragrances. Among them, it is used in large quantities as an important raw material for the production of lily aldehyde in fragrances, and has high economic value.

[0003] p-tert-butyltoluene can be prepared by alkylation of isobutylene or tert-butanol with toluene. Traditional alkylation reactions generally use liquid acids such as sulfuric acid, anhydrous AlCl3, BF3, etc. as catalysts in batch reactors. This traditional process has low production efficiency, short service life of the liquid acid catalysts, difficult post-processing, serious environmental pollution, and high requirements for equipment corrosion resistance.

[0004] To overcome these problems, fixed-bed reaction processes and corresponding heterogeneous catalysts have been developed in recent years, including solid superacid catalysts, molecular sieve catalysts, and heteropolyacid catalysts. These processes have significantly improved environmental friendliness, while also offering high target product yields, easy catalyst separation, low environmental pollution, and long service life. Therefore, in the field of alkylation, heterogeneous catalysts have replaced liquid acid catalysts. However, in actual fixed-bed reaction applications, it has been found that the proportion of para-tert-butyltoluene in the reaction products is still insufficient. While approximately 80% of the alkylation products are para-tert-butyltoluene, about 20% are inevitably meta-tert-butyltoluene. This causes two problems: first, para-tert-butyltoluene has a high value, and the presence of a portion of meta-tert-butyltoluene reduces the overall economics of the process; second, it increases separation costs, as the boiling points of meta-tert-butyltoluene and para-tert-butyltoluene are quite similar, requiring additional distillation or adsorption processes for separation, resulting in additional energy consumption. Therefore, it is necessary to convert this portion of meta-products to further improve its economic value.

[0005] Solid acid catalysts, especially molecular sieve catalysts, can serve as isomerization catalysts, promoting the conversion of meta-products to para-products. The key to this reaction lies in the selection of the molecular sieve pore structure and the matching of acidity. Therefore, adjusting the molecular sieve pore size and modifying the acidity can effectively improve the isomerization reaction performance. SAPO-5 molecular sieves, with their twelve-membered ring through-hole structure, are more practical for larger benzene ring derivatives and have a more rational acidity distribution. This effectively improves isomerization selectivity while reducing side-chain cracking reactions. Furthermore, the introduction of hierarchical pores facilitates the diffusion of reactant and product molecules, promoting the conversion of meta-isomers and significantly improving the reaction's economics. Summary of the Invention

[0006] To address the shortcomings of existing technologies, one of the technical problems this invention aims to solve is to provide a novel molded SAPO-5 molecular sieve catalyst. This novel molecular sieve catalyst has high reactivity and can effectively improve the conversion rate of reactants and the yield of target products. It is particularly suitable for application in the isomerization of aromatic compounds, especially in the isomerization of m-tert-butyltoluene to prepare p-tert-butyltoluene.

[0007] To achieve the above objectives, the first aspect of the present invention provides a shaped SAPO-5 molecular sieve catalyst, wherein the X-ray diffraction pattern of the shaped SAPO-5 molecular sieve catalyst conforms to the characteristic diffraction peaks of pure SAPO-5 molecular sieve; and the ratio of the sum of the areas of the three diffraction peaks at 2theta value of 19-25° to the sum of the areas of the three diffraction peaks corresponding to pure SAPO-5 molecular sieve is 0.9-1.1.

[0008] A second aspect of the present invention provides a method for preparing the shaped SAPO-5 molecular sieve catalyst described herein, the method comprising:

[0009] (1) Forming a solid salt from an acidic phosphorus source and a tertiary amine organic base;

[0010] (2) The solid salt, SAPO-5 molecular sieve seed crystals, aluminum source, silicon source and optional hard template agent are mixed to form a slurry, and the slurry is kneaded, shaped and dried to obtain a precursor;

[0011] (3) The precursor is hydrothermally crystallized in the presence of water as a solvent, and the hydrothermally crystallized solid is dried and calcined.

[0012] The third aspect of the present invention provides a shaped SAPO-5 molecular sieve catalyst prepared by the method of the present invention.

[0013] The fourth aspect of the present invention provides the application of the shaped SAPO-5 molecular sieve catalyst described herein in isomerization, preferably in the isomerization of aromatic compounds, and more preferably in the isomerization of C1-C5 alkyl aromatic compounds.

[0014] The fifth aspect of the present invention provides a method for preparing p-tert-butyltoluene by isomerization of m-tert-butyltoluene, the method comprising: contacting a mixed feedstock containing m-tert-butyltoluene with the catalyst described in the present invention for reaction.

[0015] The molded SAPO-5 molecular sieve catalyst described in this invention exhibits high reactivity, effectively improving reactant conversion and target product yield. Applying this molded SAPO-5 molecular sieve catalyst to the isomerization of m-tert-butyltoluene to prepare p-tert-butyltoluene offers advantages such as simple process operation, low reaction cost, and high product yield. The reason for this is presumably the use of SAPO-5 molecular sieve as a seed crystal, pre-molded with various raw materials and optionally a hard template agent, followed by crystallization of the molten catalyst precursor to prepare a highly crystalline SAPO-5 molecular sieve catalyst with hierarchical pores. This catalyst can promote the conversion of m-tert-butyltoluene to p-tert-butyltoluene, effectively improving isomerization reaction performance, reducing side-chain cracking reactions, and further increasing the yield of p-tert-butyltoluene. Furthermore, its use in fixed-bed reactions enables continuous production of p-tert-butyltoluene, demonstrating promising industrial application prospects. Attached Figure Description

[0016] Figure 1 The XRD diffraction patterns are those of the catalyst sample from Example 1 and the pure SAPO-5 molecular sieve standard sample.

[0017] Figure 2 This is a scanning electron microscope image of the catalyst sample from Example 1. Detailed Implementation

[0018] 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.

[0019] The specific embodiments of the present invention will be described in detail below. However, it should be noted that the scope of protection of the present invention is not limited to these specific embodiments, but is determined by the claims in the appendix.

[0020] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0021] When this specification uses the prefixes "known to those skilled in the art," "prior art," or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those conventionally used in the art at the time the invention was proposed, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0022] It should be noted that the two or more aspects (or embodiments) disclosed in the context of this specification can be arbitrarily combined with each other, and the resulting technical solutions (such as methods or systems) are part of the original disclosure of this specification and also fall within the protection scope of this invention.

[0023] Unless otherwise specified, all percentages, parts, ratios, etc. mentioned in this specification are based on weight, unless being based on weight would not be in accordance with the common understanding of those skilled in the art.

[0024] This invention provides a molded SAPO-5 molecular sieve catalyst. The X-ray diffraction pattern of this molded SAPO-5 molecular sieve catalyst conforms to the characteristic diffraction peaks of pure SAPO-5 molecular sieve; and the ratio of the sum of the areas of the three diffraction peaks at 2theta values ​​of 19-25° to the sum of the areas of the three diffraction peaks corresponding to pure SAPO-5 molecular sieve is 0.9-1.1. The aforementioned molded SAPO-5 molecular sieve catalyst exhibits high reactivity, effectively improving reactant conversion and target product yield. Applying this molded SAPO-5 molecular sieve catalyst to the isomerization of m-tert-butyltoluene to prepare p-tert-butyltoluene offers advantages such as simple process operation, low reaction cost, and high product yield. Furthermore, it enables continuous production of p-tert-butyltoluene, demonstrating promising industrial application prospects.

[0025] In this invention, the specific surface area of ​​the shaped SAPO-5 molecular sieve catalyst can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the specific surface area of ​​the shaped SAPO-5 molecular sieve catalyst is 280-350 m². 2 ·g -1 Preferably 310-330m 2 ·g -1 The catalyst with the aforementioned preferred specific surface area exhibits high reactivity and can effectively improve reactant conversion and target product yield.

[0026] In this invention, the mesoporous specific surface area of ​​the molded SAPO-5 molecular sieve catalyst can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the mesoporous specific surface area of ​​the molded SAPO-5 molecular sieve catalyst is 25-75 m². 2 ·g -1 30-60m is preferred 2 ·g -1 The aforementioned catalyst with the preferred mesoporous specific surface area facilitates the diffusion of reactant and product molecules and promotes the transformation of meta-isomers, making it particularly suitable for application in the isomerization of m-tert-butyltoluene to prepare p-tert-butyltoluene.

[0027] In this invention, the strength of the molded SAPO-5 molecular sieve catalyst can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the strength of the molded SAPO-5 molecular sieve catalyst is 60-90 N / cm.

[0028] In this invention, the crystallite size of the shaped SAPO-5 molecular sieve catalyst can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the crystallite size of the shaped SAPO-5 molecular sieve catalyst is 300-1000 nm, preferably 400-750 nm. The catalyst using the aforementioned preferred crystallite size exhibits high reactivity and can effectively improve reactant conversion and target product yield.

[0029] This invention is applicable to catalysts with various molding morphologies, for example, the molded SAPO-5 molecular sieve catalyst has a circular and / or clover-shaped cross-section with a diameter of 1-2 mm. The above is illustrative but does not limit the scope of the invention.

[0030] Catalysts possessing the aforementioned characteristics of this invention can achieve the objectives of this invention, and there are no special requirements for their preparation methods. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, this invention provides a method for preparing the shaped SAPO-5 molecular sieve catalyst of this invention, the method comprising:

[0031] (1) Forming a solid salt from an acidic phosphorus source and a tertiary amine organic base;

[0032] (2) The solid salt, SAPO-5 molecular sieve seed crystals, aluminum source, silicon source and optional hard template agent are mixed to form a slurry, and the slurry is kneaded, shaped and dried to obtain a precursor;

[0033] (3) The precursor is hydrothermally crystallized in the presence of water as a solvent, and the hydrothermally crystallized solid is dried and calcined.

[0034] In this invention, the range of types of acidic phosphorus sources is relatively wide. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the acidic phosphorus source is selected from one or more of phosphoric acid, ammonium dihydrogen phosphate, and pyrophosphoric acid, preferably phosphoric acid and / or pyrophosphoric acid, and more preferably a mixture of phosphoric acid and pyrophosphoric acid. The preparation process using the aforementioned preferred phosphorus source is simple to operate, has low reaction cost, and the prepared catalyst has high reactivity, effectively improving the reactant conversion rate and the yield of the target product.

[0035] In this invention, the amount of the mixture of phosphoric acid and pyrophosphate can be selected from a wide range. The following is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the content of each of the mixture of phosphoric acid and pyrophosphate is not less than 10 wt%. In the embodiments of the invention, the amount of the mixture of phosphoric acid and pyrophosphate is 50 wt% phosphoric acid, 50 wt% pyrophosphate, and 30 wt% phosphoric acid and 70 wt% pyrophosphate, as examples, to illustrate the advantages of the invention, but do not limit the scope of the invention.

[0036] In this invention, the range of tertiary amine organic bases is relatively wide. The following examples illustrate this, but do not limit the scope of the invention. According to a preferred embodiment of the invention, the tertiary amine organic base is selected from one or more of triethylamine, tri-n-propylamine, tributylamine, and tetraethylammonium hydroxide, preferably triethylamine. In this embodiment, triethylamine is used as an example to illustrate the advantages of the invention, but this does not limit the scope of the invention. The catalyst prepared using the aforementioned preferred tertiary amine organic base has high reactivity and can effectively improve the reactant conversion rate and the yield of the target product.

[0037] In this invention, the amount of acidic phosphorus source and tertiary amine organic base can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the molar ratio of acidic phosphorus source to tertiary amine organic base is 1:0.9-1.1.

[0038] In this invention, in step (1), there are no special requirements for the specific method of forming a solid salt from an acidic phosphorus source and a tertiary amine organic base. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the step of forming a solid salt from an acidic phosphorus source and a tertiary amine organic base includes: contacting and reacting the acidic phosphorus source and the tertiary amine organic base in the presence of a dispersant, followed by separation, washing, and drying to obtain a solid salt.

[0039] In this invention, the range of types of dispersants is relatively wide. The following examples are illustrative but do not limit the scope of the invention. According to a preferred embodiment of the invention, the dispersant is selected from one or more C1-C4 alcohols, preferably from one or more of methanol, ethanol, isopropanol, and tert-butanol. In this embodiment, ethanol is used as an example to illustrate the advantages of the invention, but this does not limit the scope of the invention.

[0040] In this invention, the amount of dispersant can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the mass ratio of the phosphorus source to the dispersant is 1:1-2. The catalyst prepared using the aforementioned preferred amount of dispersant has high reactivity and can effectively improve the reactant conversion rate and the yield of the target product.

[0041] In this invention, there are no special requirements for the contact method of the phosphorus source, the tertiary amine organic base and the dispersant. Conventional contact methods in the art can achieve the purpose of this invention. For example, stirring contact is generally used. In the embodiments of this invention, the contact method of the phosphorus source, the tertiary amine organic base and the dispersant is to add the phosphorus source and the tertiary amine organic base dropwise to the dispersant while stirring. This is an example to illustrate the advantages of this invention, but it does not limit the scope of this invention.

[0042] In this invention, there are no special requirements for the contact temperature. The conventional contact temperature in the art is applicable to this invention, generally 20-60°C. The contact temperature in the embodiments of this invention is based on room temperature as an example to illustrate the advantages of this invention, but does not limit the scope of this invention.

[0043] In this invention, there are no special requirements for the contact time, which is adjusted according to the contact temperature. It can generally be 1-5 hours. In this embodiment of the invention, the contact time is 2 hours as an example to illustrate the advantages of the invention, but this does not limit the scope of the invention.

[0044] In this invention, there are no special requirements for the solid-liquid separation method after the contact reaction. Commonly used separation methods can be used in this invention. In the embodiments of this invention, the solid-liquid separation method after the contact reaction is illustrated by vacuum filtration as an example to illustrate the advantages of this invention, but this does not limit the scope of this invention.

[0045] In this invention, there are no special requirements for the washing solvent. Commonly used washing solvents can be used in this invention. In the embodiments of this invention, anhydrous ethanol is used as an example to illustrate the advantages of this invention, but this does not limit the scope of this invention.

[0046] In this invention, there are no special requirements for the drying temperature of the solid salt. Commonly used drying conditions are applicable to this invention, generally 30-100℃. In the embodiments of this invention, the drying temperature of the solid salt is 80℃ as an example to illustrate the advantages of this invention, but it does not limit the scope of this invention.

[0047] In this invention, there are no special requirements for the drying time of the solid salt. The drying time is adjusted according to the drying temperature. Commonly used drying times are applicable to this invention, such as 4-12 hours.

[0048] In this invention, the range of types of aluminum sources that can be selected is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the aluminum source is selected from one or more of boehmite, aluminum isopropoxide, aluminum hydroxide, and aluminum nitrate, preferably aluminum isopropoxide and / or boehmite.

[0049] In this invention, the range of silicon sources that can be selected is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the silicon source is selected from one or more of silica, silica sol, and tetraethyl orthosilicate, preferably silica sol.

[0050] In this invention, the hard template agent added in step (2) is for preparing a catalyst containing mesoporous structures. The range of types of hard template agents is relatively wide. The following is an illustrative example, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the hard template agent is selected from one or more of stearic acid, glucose, cyclodextrin (molecular weight 975-1297), polyethylene glycol (molecular weight 200-1000), starch, and cellulose, preferably one or more of stearic acid, polyethylene glycol, and amylopectin. In this embodiment, stearic acid, polyethylene glycol (molecular weight 400), and amylopectin are used as examples to illustrate the advantages of this invention, but this does not limit the scope of this invention. The catalyst prepared using the aforementioned preferred hard template agent facilitates the diffusion of reactant and product molecules and promotes the conversion of meta-isomers. Applying this catalyst to the isomerization of m-tert-butyltoluene to prepare p-tert-butyltoluene can effectively improve the reactant conversion rate and the yield of the target product.

[0051] In this invention, the amounts of the solid salt, aluminum source, and silicon source can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the solid salt is calculated as P2O5, the aluminum source as Al2O3, and the silicon source as SiO2, with a molar ratio of P2O5:Al2O3:SiO2 of 1:0.9-1:0.25-0.35. The catalyst prepared using the aforementioned preferred amounts of solid salt, aluminum source, and silicon source exhibits high reactivity and can effectively improve the reactant conversion rate and the yield of the target product.

[0052] In this invention, the amount of SAPO-5 molecular sieve seed crystals can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the content of SAPO-5 molecular sieve seed crystals in the slurry is 1-15 wt%, preferably 5-13 wt%, based on the total mass of the solid mixture. The total mass of the solid mixture refers to the total mass of solid salt (calculated as oxide), SAPO-5 molecular sieve seed crystals, aluminum source (calculated as oxide), silicon source (calculated as oxide), and hard template agent.

[0053] In this invention, the amount of the hard template agent can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the content of the hard template agent is 2-10 wt% of the dry basis content of the catalyst, preferably 5-7 wt%.

[0054] In this invention, the catalyst dry base refers to the total solid mass in oxide form after calcination in step (3). For example, in this invention, the catalyst dry base is calculated based on the total mass of oxides such as P2O5, Al2O3 and SiO2.

[0055] In this invention, there are no special requirements for the type of solvent used in the slurry. Conventional solvents in the art are all applicable to this invention. In the embodiments of this invention, water is used as an example to illustrate the advantages of this invention, but this does not limit the scope of this invention.

[0056] In this invention, the addition of solvent in step (2) is to make the slurry better kneaded and shaped. The amount of solvent used in the slurry can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the solvent content in the slurry is 15-30 wt%.

[0057] In this invention, there are no special requirements for the kneading time of the slurry, as long as pre-forming is achieved, for example, generally 1-2 hours. In this embodiment of the invention, the kneading time of 1 hour is used as an example to illustrate the advantages of the invention, but it does not limit the scope of the invention.

[0058] In this invention, there are no special requirements for the kneading and forming method. Conventional forming methods in the art can be applied to this invention. In this embodiment of the invention, the kneading and forming method adopts extrusion molding. Specifically, the kneaded preform is added to an extruder with a perforated plate for forming, and the target shape is obtained, for example, a circular or clover-shaped strip with a cross-section of 1-2 mm in diameter.

[0059] In this invention, the drying temperature of the slurry after molding can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the drying temperature of the slurry after molding is 50-150°C. In this embodiment of the invention, the drying temperature of the slurry after molding is 110°C, which is used as an example to illustrate the advantages of the invention, but it does not limit the scope of the invention.

[0060] In this invention, there are no special requirements for the drying time of the slurry after molding; the time is adjusted according to the drying temperature, typically 4-12 hours. The above is illustrative but does not limit the scope of the invention.

[0061] In this invention, the amount of water used in the hydrothermal crystallization of the precursor can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the mass ratio of the precursor to water is 1:1-10, preferably 1:2-7.

[0062] In this invention, the conditions for the hydrothermal crystallization of the precursor can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the temperature of the hydrothermal crystallization is 170-200°C, preferably 180-190°C.

[0063] In this invention, the hydrothermal crystallization time of the precursor is not specifically required, but is adjusted according to the hydrothermal crystallization temperature, for example, generally 15-32 hours, preferably 16-20 hours. The hydrothermal crystallization times of 16 hours, 18 hours, and 20 hours in the embodiments of this invention are used as examples to illustrate the advantages of this invention, but do not limit the scope of this invention.

[0064] In this invention, the temperature range for drying the solid after hydrothermal crystallization is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the temperature for drying the solid after hydrothermal crystallization is 50-150°C.

[0065] In this invention, there are no special requirements for the drying time of the solid after hydrothermal crystallization; the time is adjusted according to the drying temperature, typically 4-12 hours. The above is illustrative but does not limit the scope of the invention.

[0066] In this invention, the roasting conditions can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the roasting temperature is 450-600℃, preferably 500-600℃. In this embodiment of the invention, the roasting temperature of 550℃ is used as an example to illustrate the advantages of the invention, but it does not limit the scope of the invention.

[0067] In this invention, the roasting time is not specifically required and is adjusted according to the roasting temperature, for example, generally 2-8 hours, preferably 3-4 hours. The roasting time of 4 hours in this embodiment is used as an example to illustrate the advantages of the invention, but does not limit the scope of the invention.

[0068] This invention provides a shaped SAPO-5 molecular sieve catalyst prepared by the method described herein. The shaped SAPO-5 molecular sieve catalyst of this invention exhibits high reactivity, effectively improving reactant conversion and target product yield. Applying this shaped SAPO-5 molecular sieve catalyst to the isomerization of m-tert-butyltoluene to prepare p-tert-butyltoluene offers advantages such as simple process operation, low reaction cost, and high product yield. Furthermore, it enables continuous production of p-tert-butyltoluene, demonstrating promising industrial application prospects.

[0069] According to a preferred embodiment of the present invention, the X-ray diffraction pattern of the shaped SAPO-5 molecular sieve catalyst conforms to the characteristic diffraction peaks of pure SAPO-5 molecular sieve; and the ratio of the sum of the areas of the three diffraction peaks at 2theta value of 19-25° to the sum of the areas of the three diffraction peaks corresponding to pure SAPO-5 molecular sieve is 0.9-1.1.

[0070] According to a preferred embodiment of the present invention, the specific surface area of ​​the shaped SAPO-5 molecular sieve catalyst is 280-350 m². 2 ·g -1 Preferably 310-330m 2 ·g -1 .

[0071] According to a preferred embodiment of the present invention, the mesoporous specific surface area of ​​the shaped SAPO-5 molecular sieve catalyst is 25-75 m². 2 ·g -1 30-60m is preferred 2 ·g -1 .

[0072] According to a preferred embodiment of the present invention, the strength index of the molded SAPO-5 molecular sieve catalyst is 60-90 N / cm.

[0073] According to a preferred embodiment of the present invention, the crystal size of the shaped SAPO-5 molecular sieve catalyst is 300-1000 nm, preferably 400-750 nm.

[0074] According to a preferred embodiment of the present invention, the cross-section of the shaped SAPO-5 molecular sieve catalyst is circular and / or clover-shaped with a diameter of 1-2 mm.

[0075] Accordingly, the present invention provides the application of the shaped SAPO-5 molecular sieve catalyst described herein in isomerization, preferably in the isomerization of aromatic compounds, and more preferably in the isomerization of C1-C5 alkyl aromatic compounds.

[0076] This invention provides a method for isomerizing m-tert-butyltoluene to prepare p-tert-butyltoluene, the method comprising: contacting a mixed feedstock containing m-tert-butyltoluene with the catalyst described in this invention for reaction.

[0077] In this invention, the range of selectable mixed raw materials containing m-tert-butyltoluene is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the m-tert-butyltoluene content in the mixed raw material is 15-35 wt%, preferably 20-30 wt%; more preferably, the mixed raw material containing m-tert-butyltoluene contains both m-tert-butyltoluene and p-tert-butyltoluene, and the total content of m-tert-butyltoluene and p-tert-butyltoluene is above 98%.

[0078] In this invention, there are no special requirements for the source of the mixed raw material containing m-tert-butyltoluene; for example, it can generally be derived from alkylation products.

[0079] In this invention, the conditions for contacting the mixed feedstock containing m-tert-butyltoluene with the catalyst described herein can be selected over a wide range. The following is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the contact reaction temperature is 200-350°C, preferably 260-280°C. In the embodiments of this invention, contact reaction temperatures of 260°C, 270°C, and 280°C are used as examples to illustrate the advantages of the invention, but they do not limit the scope of the invention.

[0080] In this invention, the liquid hourly space velocity (LISH) for contacting the mixed feedstock containing m-tert-butyltoluene with the catalyst described herein can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the LISH of the contact reaction is 0.5-2 h⁻¹. -1 In this embodiment of the invention, the liquid hourly space velocity (LHSV) of the contact reaction is 1 h⁻¹. -1 The advantages of the present invention are illustrated by way of example, but are not limited thereto.

[0081] In this invention, the pressure range for contacting the mixed feedstock containing m-tert-butyltoluene with the catalyst described herein is relatively wide. The following is an illustrative example, but does not limit the scope of the invention. According to a preferred embodiment of the invention, the contact reaction pressure is 0.02-2 MPa. In this embodiment, the contact reaction pressure is 0.1 MPa as an example to illustrate the advantages of the invention, but does not limit the scope of the invention.

[0082] The molded SAPO-5 molecular sieve catalyst described in this invention exhibits high reactivity, effectively improving reactant conversion and target product yield. Applying this molded SAPO-5 molecular sieve catalyst to the isomerization of m-tert-butyltoluene to prepare p-tert-butyltoluene offers advantages such as simple process operation, low reaction cost, and high product yield. The reason for this is presumably the use of SAPO-5 molecular sieve as a seed crystal, pre-molded with various raw materials and optionally a hard template agent, followed by crystallization of the molten catalyst precursor to prepare a highly crystalline SAPO-5 molecular sieve catalyst with hierarchical pores. This catalyst can promote the conversion of m-tert-butyltoluene to p-tert-butyltoluene, effectively improving isomerization reaction performance, reducing side-chain cracking reactions, and further increasing the yield of p-tert-butyltoluene. Furthermore, its use in fixed-bed reactions enables continuous production of p-tert-butyltoluene, demonstrating promising industrial application prospects.

[0083] The present invention will be described in detail below through examples. The area and parameters of the catalyst diffraction peaks were measured by powder X-ray diffraction; the specific surface area and mesoporous specific surface area of ​​the catalyst were measured by N2 physical adsorption (BET); the strength of the catalyst was measured by an intensity meter; and the crystallite size of the catalyst was measured by scanning electron microscopy (SEM).

[0084] In the following examples, the conversion rate of m-tert-butyltoluene and the yield of p-tert-butyltoluene were calculated according to the following formulas:

[0085]

[0086] In this embodiment of the invention, the inner diameter is used A fixed-bed reactor with a length of 800 mm.

[0087] In this invention, SAPO-5 molecular sieve seed crystals (P2O5:Al2O3:SiO2 = 1:0.9:025) were used as the pure SAPO-5 molecular sieve described in this invention, and also as the standard sample for XRD testing. XRD results are shown in [Figure number missing]. Figure 1 Spectrum of the Chinese standard sample.

[0088]

Example 1

[0089] (1) The phosphoric acid and anhydrous ethanol were fed in a mass ratio of 1:1.5 and a molar ratio of 1:1.1. Phosphoric acid and triethylamine were added dropwise to anhydrous ethanol under stirring at room temperature. After stirring for 2 hours, the mixture was filtered, washed with anhydrous ethanol, and dried at 80°C for 4 hours to obtain a solid salt.

[0090] (2) Solid salt, SAPO-5 molecular sieve seed crystals, boehmite powder, silica sol, and amylopectin were mixed evenly, wherein the molar ratio of solid salt, boehmite powder, and silica sol was P2O5:Al2O3:SiO2 = 1:0.9:025; based on the total mass of the solid mixture, the content of SAPO-5 molecular sieve seed crystals was 10wt%, and the content of amylopectin was 5wt%; deionized water was added dropwise according to the target slurry content of 15wt% water (including water brought in by other raw materials), and the resulting slurry was kneaded for 1 hour. The kneaded preform was added to an extruder equipped with a perforated plate for molding, and a circular strip with a cross-sectional diameter of 1 mm was obtained. The molding pressure was 2 MPa, and the strip was dried at 110°C for 4 hours to obtain the precursor.

[0091] (3) The precursor with a mass ratio of 1:2 was mixed with water and fed into a crystallization kettle for hydrothermal crystallization, wherein the crystallization was carried out at 180°C for 16 hours; the solid after hydrothermal crystallization was dried at 100°C for 4 hours and then calcined at 550°C for 4 hours to obtain catalyst S1.

[0092] The diffraction pattern obtained through XRD testing is shown below. Figure 1 The 2theta value of catalyst S1 is 0.92, which is the ratio of the sum of the areas of the three diffraction peaks at 19-25° to the sum of the areas of the three diffraction peaks corresponding to the pure SAPO-5 molecular sieve standard. BET analysis shows that the specific surface area of ​​catalyst S1 is 298 m². 2 ·g -1 The mesoporous specific surface area is 44m³. 2 ·g -1 The strength of catalyst S1 was measured to be 73 N / cm using a strength tester. The SEM image is shown below. Figure 2 The crystallite size of catalyst S1 is 500-700 nm.

[0093] The reaction of the above catalysts was evaluated:

[0094] 1 g of catalyst S1 prepared according to the above method was loaded into a fixed-bed reactor, and a mixed feedstock containing m-tert-butyltoluene was introduced, wherein the m-tert-butyltoluene content was 28.5 wt% (the remainder being p-tert-butyltoluene). The reaction temperature was 280 °C, and the liquid hourly space velocity was 1.0 h⁻¹. -1 The reaction pressure was 0.1 MPa, the conversion rate of m-tert-butyltoluene was 74.0%, and the yield of p-tert-butyltoluene was 66.4%.

[0095]

Example 2

[0096] (1) The phosphoric acid and anhydrous ethanol were fed in a mass ratio of 1:1.5 and a molar ratio of 1:1.1. Phosphoric acid and triethylamine were added dropwise to anhydrous ethanol under stirring at room temperature. After stirring for 2 hours, the mixture was filtered, washed with anhydrous ethanol, and dried at 80°C for 4 hours to obtain a solid salt.

[0097] (2) Solid salt, SAPO-5 molecular sieve seed crystals, boehmite powder, silica sol, and stearic acid were mixed evenly. The molar ratio of solid salt, boehmite powder, and silica sol was P2O5:Al2O3:SiO2 = 1:0.9:025. Based on the total mass of the solid mixture, the content of SAPO-5 molecular sieve seed crystals was 12.5 wt%, and the content of stearic acid was 5 wt%. Deionized water was added dropwise according to the target slurry content of 15 wt% (including water brought in by other raw materials). The resulting slurry was then kneaded for 1 hour. The kneaded preform was added to an extruder equipped with a perforated plate for molding. A circular strip with a cross-sectional diameter of 2 mm was obtained. The molding pressure was 4 MPa, and the strip was dried at 110°C for 4 hours to obtain the precursor.

[0098] (3) The precursor with a mass ratio of 1:3 was mixed with water and fed into a crystallization kettle for hydrothermal crystallization, wherein the crystallization was carried out at 180°C for 20 hours; the solid after hydrothermal crystallization was dried at 110°C for 4 hours and then calcined at 550°C for 4 hours to obtain catalyst S2.

[0099] XRD analysis showed that the 2θ value of catalyst S2 was 0.91, which was the ratio of the sum of the areas of the three diffraction peaks at 19-25° to the sum of the areas of the three diffraction peaks corresponding to the pure SAPO-5 molecular sieve standard. BET analysis showed that the specific surface area of ​​catalyst S2 was 302 m². 2 ·g -1 The mesoporous specific surface area is 51m². 2 ·g -1 The strength of catalyst S2 was 78 N / cm as measured by a strength tester, and the crystal size of catalyst S2 was 450-720 nm as measured by SEM.

[0100] The reaction of the above catalysts was evaluated:

[0101] 1 g of catalyst S2 prepared according to the above method was loaded into a fixed-bed reactor, and a mixed feedstock containing m-tert-butyltoluene was introduced, wherein the m-tert-butyltoluene content was 21.3 wt% (the remainder being p-tert-butyltoluene). The reaction temperature was 270 °C, and the liquid hourly space velocity was 1.0 h⁻¹. -1 The reaction pressure was 0.1 MPa, the conversion rate of m-tert-butyltoluene was 72.1%, and the yield of p-tert-butyltoluene was 65.4%.

[0102]

Example 3

[0103] (1) The phosphoric acid and anhydrous ethanol were fed in a mass ratio of 1:1.5 and a molar ratio of 1:1.1. Phosphoric acid and triethylamine were added dropwise to anhydrous ethanol under stirring at room temperature. After stirring for 2 hours, the mixture was filtered, washed with anhydrous ethanol, and dried at 80°C for 4 hours to obtain a solid salt.

[0104] (2) Solid salt, SAPO-5 molecular sieve seed crystals, boehmite powder, silica sol, and polyethylene glycol (molecular weight 400) were mixed evenly. The molar ratio of solid salt, boehmite powder, and silica sol was P2O5:Al2O3:SiO2 = 1:0.9:025. The content of SAPO-5 molecular sieve seed crystals was 5 wt% and the content of polyethylene glycol was 7 wt% based on the total mass of the solid mixture. Deionized water was added dropwise according to the target slurry content of 15 wt% (including water brought in by other raw materials). The resulting slurry was then kneaded for 1 hour. The kneaded preform was added to an extruder equipped with a perforated plate for molding. A clover-shaped strip with a cross-sectional diameter of 1 mm was obtained. The molding pressure was 2 MPa, and the strip was dried at 110°C for 4 hours to obtain the precursor.

[0105] (3) The precursor with a mass ratio of 1:3 was mixed with water and fed into a crystallization kettle for hydrothermal crystallization, wherein the crystallization was carried out at 190°C for 18 hours; the solid after hydrothermal crystallization was dried at 110°C for 4 hours and then calcined at 550°C for 4 hours to obtain catalyst S3.

[0106] XRD analysis showed that the 2θ value of catalyst S3 was 0.90, which was the ratio of the sum of the areas of the three diffraction peaks at 19-25° to the sum of the areas of the three diffraction peaks corresponding to the pure SAPO-5 molecular sieve standard. BET analysis showed that the specific surface area of ​​catalyst S3 was 289 m². 2 ·g -1 The mesoporous specific surface area is 43m². 2 ·g -1 The strength of catalyst S3 was measured to be 68 N / cm using a strength tester, and the crystal size of catalyst S3 was measured to be 480-670 nm using SEM.

[0107] The reaction of the above catalysts was evaluated:

[0108] 1 g of catalyst S3 prepared according to the above method was loaded into a fixed-bed reactor, and a mixed feedstock containing m-tert-butyltoluene was introduced, wherein the m-tert-butyltoluene content was 25.0 wt% (the remainder being p-tert-butyltoluene). The reaction temperature was 260 °C, and the reaction liquid hourly space velocity was 1.0 h⁻¹. -1 The reaction pressure was 0.1 MPa, the conversion rate of m-tert-butyltoluene was 65.1%, and the yield of p-tert-butyltoluene was 59.0%.

[0109]

Example 4

[0110] (1) The phosphoric acid and anhydrous ethanol were fed in a mass ratio of 1:1.5 and a molar ratio of 1:1 to triethylamine. The phosphoric acid and triethylamine were added dropwise to the anhydrous ethanol under stirring at room temperature. After stirring for 2 hours, the mixture was filtered, washed with anhydrous ethanol, and dried at 80°C for 4 hours to obtain a solid salt.

[0111] (2) Solid salt, SAPO-5 molecular sieve seed crystals, boehmite powder, silica sol, and amylopectin were mixed evenly. The molar ratio of solid salt, boehmite powder, and silica sol was P2O5:Al2O3:SiO2 = 1:0.9:025. The content of SAPO-5 molecular sieve seed crystals and amylopectin was 5wt% based on the total mass of the solid mixture. Deionized water was added dropwise according to the target slurry content of 15wt% (including water introduced from other raw materials). The resulting slurry was then kneaded for 1 hour. The kneaded preform was then fed into an extruder equipped with a perforated plate for molding. A circular strip with a cross-sectional diameter of 1 mm was obtained. The molding pressure was 2 MPa, and the strip was dried at 110°C for 4 hours to obtain the precursor.

[0112] (3) The precursor with a mass ratio of 1:7 was mixed with water and fed into a crystallization kettle for hydrothermal crystallization, wherein the crystallization was carried out at 180°C for 16 hours; the solid after hydrothermal crystallization was dried at 110°C for 4 hours and then calcined at 550°C for 4 hours to obtain catalyst S4.

[0113] XRD analysis showed that the 2θ value of catalyst S4 was 0.90, which was the ratio of the sum of the areas of the three diffraction peaks at 19-25° to the sum of the areas of the three diffraction peaks corresponding to the pure SAPO-5 molecular sieve standard. BET analysis showed that the specific surface area of ​​catalyst S4 was 283 m². 2 ·g -1 The mesoporous specific surface area is 32m². 2 ·g -1 The strength of catalyst S4 was measured to be 66 N / cm using a strength tester, and the crystal size of catalyst S4 was measured to be 450-720 nm using SEM.

[0114] The reaction of the above catalysts was evaluated:

[0115] 1 g of catalyst S4 prepared according to the above method was loaded into a fixed-bed reactor, and a mixed feedstock containing m-tert-butyltoluene was introduced, wherein the m-tert-butyltoluene content was 28.5 wt% (the remainder being p-tert-butyltoluene). The reaction temperature was 280 °C, and the liquid hourly space velocity was 1.0 h⁻¹. -1 The reaction pressure was 0.1 MPa, the conversion rate of m-tert-butyltoluene was 68.6%, and the yield of p-tert-butyltoluene was 62.3%.

[0116]

Example 5

[0117] Following the method steps of Example 1, except that a mixture of 50 wt% phosphoric acid and 50 wt% pyrophosphoric acid was used instead of phosphoric acid to prepare catalyst S5.

[0118] XRD analysis showed that the 2θ value of catalyst S5 was 0.95, which was the ratio of the sum of the areas of the three diffraction peaks at 19-25° to the sum of the areas of the three diffraction peaks corresponding to the pure SAPO-5 molecular sieve standard. BET analysis showed that the specific surface area of ​​catalyst S5 was 323 m². 2 ·g -1 The mesoporous specific surface area is 57m². 2 ·g -1 The strength of catalyst S5 was measured to be 82 N / cm by a strength tester, and the crystal size of catalyst S5 was measured to be 560-680 nm by SEM.

[0119] The reaction of the catalyst S5 was evaluated according to the method of Example 1:

[0120] The conversion rate of m-tert-butyltoluene was 81.1%, and the yield of p-tert-butyltoluene was 73.8%.

[0121]

Example 6

[0122] Following the method steps of Example 1, except that a mixture of 30 wt% phosphoric acid and 70 wt% pyrophosphoric acid was used instead of phosphoric acid to prepare catalyst S6.

[0123] XRD analysis showed that the 2θ value of catalyst S6 was 0.93, which was the ratio of the sum of the areas of the three diffraction peaks at 19-25° to the sum of the areas of the three diffraction peaks corresponding to the pure SAPO-5 molecular sieve standard. BET analysis showed that the specific surface area of ​​catalyst S5 was 315 m². 2 ·g -1 The mesoporous specific surface area is 54 m². 2 ·g -1 The strength of catalyst S5 was measured to be 80 N / cm by a strength tester, and the crystal size of catalyst S5 was measured to be 530-700 nm by SEM.

[0124] The reaction of the catalyst S6 described above was evaluated according to the method in Example 1:

[0125] The conversion rate of m-tert-butyltoluene was 78.2%, and the yield of p-tert-butyltoluene was 70.5%.

[0126] Comparative Example 1

[0127] 40g of H-SAPO-5 molecular sieve (pure SAPO-5 molecular sieve standard) with a SiO2:Al2O3 molar ratio of 0.25:1 was selected, and 28.6g of pseudoboehmite (70% Al2O3 content) was added as a binder. Then, 20g of water and 3g of nitric acid (65-67wt%) molding aid were added and kneaded for 1h. The kneaded preform was then fed into an extruder equipped with a perforated plate for molding, resulting in circular strips with a cross-sectional diameter of 1mm. The molding pressure was 2MPa, and the strips were dried at 110℃ for 4h, followed by calcination at 550℃ for 4h to obtain catalyst D1.

[0128] XRD analysis showed that the 2theta value of catalyst D1 was 0.78, which was the ratio of the sum of the areas of the three diffraction peaks at 19-25° to the sum of the areas of the three diffraction peaks corresponding to the pure SAPO-5 molecular sieve standard. BET analysis showed that the specific surface area of ​​catalyst D1 was 233 m². 2 ·g -1 The mesoporous specific surface area is 23m². 2 ·g -1 The strength of catalyst D1 was 70 N / cm as measured by a strength tester, and the crystal size of catalyst D1 was 2000-10000 nm as measured by SEM.

[0129] The reaction of the above catalyst D1 was evaluated according to the method of Example 1:

[0130] The conversion rate of m-tert-butyltoluene was 59.7%, and the yield of p-tert-butyltoluene was 52.1%.

[0131] Comparative Example 2

[0132] (1) Phosphoric acid, triethylamine, SAPO-5 molecular sieve seed crystals, boehmite powder, silica sol, and amylopectin were mixed evenly. The molar ratio of phosphoric acid to triethylamine was 1:1.1, and the molar ratio of phosphoric acid, boehmite powder, and silica sol was P2O5:Al2O3:SiO2 = 1:0.9:025. The content of SAPO-5 molecular sieve seed crystals was 10wt% and the content of amylopectin was 5wt% based on the total mass of the solid mixture. Deionized water was added dropwise according to the target slurry content of 15wt% water (including water brought in by other raw materials), and the resulting slurry was kneaded for 1 hour. The kneaded preform was added to an extruder equipped with a perforated plate for molding to obtain a circular strip with a cross-sectional diameter of 1mm. The molding pressure was 2MPa, and the strip was dried at 110℃ for 4 hours to obtain the precursor.

[0133] (2) The precursor with a mass ratio of 1:2 was mixed with water and fed into a crystallization vessel for hydrothermal crystallization, wherein the crystallization was carried out at 180°C for 16 hours; the solid after hydrothermal crystallization was dried at 100°C for 4 hours and then calcined at 550°C for 4 hours to obtain catalyst D2.

[0134] XRD analysis showed that the 2theta value of catalyst D2 was 0.25 times the ratio of the sum of the areas of the three diffraction peaks at 19-25° to the sum of the areas of the three diffraction peaks corresponding to pure SAPO-5 molecular sieve. BET analysis showed that the specific surface area of ​​catalyst 1 was 90 m². 2 ·g -1 The mesoporous specific surface area is 7m². 2 ·g -1 The strength of catalyst 1 was measured to be 20 N / cm by a strength tester, and the crystal size of catalyst D2 was measured to be 5000-20000 nm by SEM.

[0135] The reaction of the above catalyst D2 was evaluated according to the method of Example 1:

[0136] The conversion rate of m-tert-butyltoluene was 32.0%, and the yield of p-tert-butyltoluene was 10.8%.

[0137] 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 shaped SAPO-5 molecular sieve catalyst characterized in that, The X-ray diffraction pattern of the formed SAPO-5 molecular sieve catalyst conforms to the characteristic diffraction peaks of pure SAPO-5 molecular sieve; and the ratio of the sum of the areas of the three diffraction peaks at 2theta value of 19-25° to the sum of the areas of the three diffraction peaks corresponding to pure SAPO-5 molecular sieve is 0.9-1.

1.

2. The catalyst according to claim 1, wherein, The specific surface area of ​​the molded SAPO-5 molecular sieve catalyst is 280-350 m². 2 ·g - 1. Preferably, it is 310-330m 2 ·g -1 ; and / or The mesoporous specific surface area of the shaped SAPO-5 molecular sieve catalyst is 25-75 m 2 ·g -1 , preferably 30-60 m 2 ·g -1 ; and / or The strength of the molded SAPO-5 molecular sieve catalyst is 60-90 N / cm; and / or The crystallite size of the shaped SAPO-5 molecular sieve catalyst is 300-1000 nm, preferably 400-750 nm; and / or The cross-section of the molded SAPO-5 molecular sieve catalyst is circular and / or clover-shaped with a diameter of 1-2 mm.

3. A process for the preparation of a shaped SAPO-5 molecular sieve catalyst, characterized in that, The method includes: (1) Forming a solid salt from an acidic phosphorus source and a tertiary amine organic base; (2) The solid salt, SAPO-5 molecular sieve seed crystals, aluminum source, silicon source and optional hard template agent are mixed to form a slurry, and the slurry is kneaded, shaped and dried to obtain a precursor; (3) The precursor is hydrothermally crystallized in the presence of water as a solvent, and the hydrothermally crystallized solid is dried and calcined.

4. The preparation method according to claim 3, wherein, In step (1), The acidic phosphorus source is selected from one or more of phosphoric acid, ammonium dihydrogen phosphate, and pyrophosphate, preferably phosphoric acid and / or pyrophosphate, more preferably a mixture of phosphoric acid and pyrophosphate, each with a content of not less than 10 wt%; and / or The tertiary amine organic base is selected from one or more of triethylamine, tri-n-propylamine, tributylamine, and tetraethylammonium hydroxide, preferably triethylamine; and / or The molar ratio of the acidic phosphorus source to the tertiary amine organic base is 1:0.9-1.1; and / or The step of forming a solid salt from an acidic phosphorus source and a tertiary amine organic base includes: reacting the acidic phosphorus source and the tertiary amine organic base in the presence of a dispersant, followed by separation, washing, and drying to obtain a solid salt; Preferably, the dispersant is selected from one or more C1-C4 alcohols, and more preferably from one or more methanol, ethanol, isopropanol, and tert-butanol; and / or The mass ratio of the acidic phosphorus source to the dispersant is 1:1-2.

5. The preparation method according to claim 3 or 4, wherein, In step (2), The aluminum source is selected from one or more of boehmite, aluminum isopropoxide, aluminum hydroxide, and aluminum nitrate, preferably aluminum isopropoxide and / or boehmite; and / or The silicon source is selected from one or more of silica, silica sol, and tetraethyl orthosilicate, preferably silica sol; and / or The hard template agent is selected from one or more of stearic acid, glucose, cyclodextrin, polyethylene glycol, starch, and cellulose, preferably one or more of stearic acid, polyethylene glycol, and amylopectin; and / or The solid salt is calculated as P2O5, the aluminum source as Al2O3, and the silicon source as SiO2, with a molar ratio of P2O5:Al2O3:SiO2 of 1:0.9-1:0.25-0.35; and / or In the slurry, the content of the SAPO-5 molecular sieve seed crystals is 1-15 wt%, preferably 5-13 wt%, based on the total mass of the solid mixture; and / or The content of the hard template agent is 2-10 wt% of the dry basis content of the catalyst, preferably 5-7 wt%; and / or The solvent content in the slurry is 15-30 wt%.

6. The production method according to any one of claims 3 to 5, wherein In step (2), The kneading time is 1-2 hours; and / or The molding process employs extrusion molding; and / or The molding pressure is 0.5-4 MPa.

7. The method of making according to any one of claims 3-6, wherein, In step (3), The mass ratio of the precursor to water is 1:1-10, preferably 1:2-7; and / or The conditions for hydrothermal crystallization include: a temperature of 170-200℃, preferably 180-190℃; and / or a time of 15-32h, preferably 16-20h. and / or The calcination conditions include: a temperature of 450-600℃, preferably 500-600℃; and / or a time of 2-8h, preferably 3-4h.

8. The shaped SAPO-5 molecular sieve catalyst prepared by the method according to any one of claims 3-7; Preferably, the X-ray diffraction pattern of the molded SAPO-5 molecular sieve catalyst conforms to the characteristic diffraction peaks of pure SAPO-5 molecular sieve; and the ratio of the sum of the areas of the three diffraction peaks at 2theta value of 19-25° to the sum of the areas of the three diffraction peaks corresponding to pure SAPO-5 molecular sieve is 0.9-1.1; and / or The specific surface area of the shaped SAPO-5 molecular sieve catalyst is 280-350 m 2 ·g -1 , preferably 310-330 m 2 ·g -1 ; and / or The mesoporous specific surface area of the shaped SAPO-5 molecular sieve catalyst is 25-75 m 2 ·g -1 , preferably 30-60 m 2 ·g -1 ; and / or The strength of the molded SAPO-5 molecular sieve catalyst is 60-90 N / cm; and / or The crystallite size of the shaped SAPO-5 molecular sieve catalyst is 300-1000 nm, preferably 400-750 nm; and / or The cross-section of the molded SAPO-5 molecular sieve catalyst is circular and / or clover-shaped with a diameter of 1-2 mm.

9. The application of the shaped SAPO-5 molecular sieve catalyst according to any one of claims 1-2 and 8 in isomerization, preferably in the isomerization of aromatic compounds, and more preferably in the isomerization of C1-C5 alkyl aromatic compounds.

10. A method for isomerizing m-tert-butyltoluene to prepare p-tert-butyltoluene, characterized in that, The method includes: reacting a mixed feedstock containing m-tert-butyltoluene with the catalyst described in any one of claims 1-2 and 8; Preferably, the m-tert-butyltoluene content in the mixed raw material containing m-tert-butyltoluene is 15-35 wt%, more preferably 20-30 wt%; more preferably, the mixed raw material containing m-tert-butyltoluene contains m-tert-butyltoluene and p-tert-butyltoluene, and the total content of m-tert-butyltoluene and p-tert-butyltoluene is above 98%. and / or The conditions for a contact reaction include: The temperature is 200-350℃, preferably 260-280℃; and / or Liquid hourly space velocity was 0.5-2 h -1 ; and / or The pressure is 0.02-2 MPa.

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