Multi-metal composite heteropolyacid catalyst, preparation method thereof and method for catalytically preparing resin

Abstract

The invention relates to the technical field of preparation of alicyclic epoxy resin, in particular to a multi-metal composite heteropolyacid catalyst, a preparation method of the multi-metal composite heteropolyacid catalyst and a method for catalytically preparing resin. The preparation method of the multi-metal composite heteropolyacid catalyst comprises the following steps: by adopting a chemical precipitation method, taking an aluminum source, ammonia water and isopropanol as raw materials, aging and filtering to obtain a catalyst precursor, and drying and roasting the catalyst precursor to obtain a catalyst carrier; and preparing an aqueous solution of the active component, performing equivalent-volume impregnation on the catalyst carrier and the aqueous solution of the active component, and then drying and roasting to obtain the multi-metal composite heteropolyacid catalyst. The prepared catalyst is adopted to catalytically prepare 3, 4-epoxy cyclohexyl methyl-3, 4-epoxy cyclohexyl formate, by-products can be reduced, the yield can be improved, expensive raw materials do not need to be used, the cost is low, the process is simple, the processing cost of epoxy resin can be reduced, and the processing fluidity can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of preparation of alicyclic epoxy resins, and in particular to a multi-metal composite heteropoly acid catalyst and a preparation method thereof, and a method for catalytically preparing resins. Background Art

[0002] 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate currently used in the market is a high-end resin main body with advantages such as high strength and strong anti-yellowing ability. At present, the production process of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate is mainly based on the acetic acid hydrogen peroxide oxidation method, that is, 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester is epoxidized to 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate using acetic acid and hydrogen peroxide. However, the existing process has the disadvantage of a large amount of acetic acid or sodium acetate by-products in the continuous production process, low yield and high cost. Summary of the invention

[0003] In order to solve the above-mentioned technical problems existing in the prior art, the present invention provides a multi-metal composite heteropoly acid catalyst and a preparation method thereof, and a method for catalytically preparing a resin. The present invention prepares 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate resin by utilizing a novel catalyst, a catalyst preparation process and a preparation method, thereby reducing by-products and improving yield. At the same time, no expensive raw materials are required, the cost is low, the process is simple, the processing cost of the epoxy resin can be reduced, and the processing fluidity can be improved.

[0004] The technical solution of the present invention to solve the above technical problems is:

[0005] The first aspect of the present invention is to provide a method for preparing a multi-metal composite heteropoly acid catalyst, comprising the following steps:

[0006] (1) Preparation of catalyst carrier: using chemical precipitation method, aluminum source, ammonia water and isopropanol as raw materials, aging and filtering to obtain catalyst precursor, and drying and calcining the catalyst precursor to obtain γ-Al2O3 catalyst carrier;

[0007] (2) Loading catalyst: weighing a certain mass of γ-Al2O3 catalyst carrier, calculating the mass of the required active component according to the water absorption rate and loading amount of the γ-Al2O3 catalyst carrier, preparing an aqueous solution of the active component, impregnating the γ-Al2O3 catalyst carrier with the aqueous solution of the active component in equal volumes, and then drying and calcining to obtain the multi-metal composite heteropoly acid catalyst;

[0008] Wherein, the active component is any one or more of silicotungstic acid, phosphomolybdic acid, nickel-doped silicotungstic acid, nickel-doped phosphomolybdic acid, cobalt-doped silicotungstic acid, and cobalt-doped phosphomolybdic acid.

[0009] The water absorption rate of the γ-Al2O3 catalyst carrier is 90%.

[0010] Here, equal volume impregnation, that is, equal volume solution impregnation, means that the volume or mass of the aqueous solution of the active component is equal to the volume or mass of the solution required for complete wetting of the γ-Al2O3 catalyst carrier.

[0011] The water absorption rate of the γ-Al2O3 catalyst carrier is calculated by the following method: a certain mass t0 of the γ-Al2O3 catalyst carrier (for example, 10 g) is weighed and completely immersed in deionized water for 30 minutes, then the γ-Al2O3 catalyst carrier is taken out and the surface moisture is absorbed, and the mass t is weighed again. The increased mass (t-t0) divided by the mass t0 before immersion is the water absorption rate, that is, the water absorption rate = (t-t0) / t0.

[0012] According to the loading amount and the calculated water absorption rate results, an aqueous solution of the active component of a certain concentration is prepared to impregnate the γ-Al2O3 catalyst carrier with equal volume, so that the active component is completely absorbed by the catalyst carrier.

[0013] Furthermore, in step (1), crystalline aluminum chloride (AlCl3·6H2O) is used as an aluminum source, and aqueous ammonia is added dropwise to an aqueous solution of crystalline aluminum chloride and isopropanol under stirring at 35°C, aged at 65°C for 12h, and then filtered to obtain a catalyst precursor, and the catalyst precursor is dried at 120°C for 12h, and then calcined at 450°C for 4h to obtain a γ-Al2O3 catalyst carrier.

[0014] The stirring speed is 300RPM.

[0015] Furthermore, in step (2), the loading amount of the silicotungstic acid and phosphomolybdic acid is 5-15%, and the loading amount of the nickel and cobalt is 0.1-2%.

[0016] The loading amount of the silicotungstic acid and phosphomolybdic acid is preferably 10%, and the loading amount of the doped nickel and doped cobalt is preferably 0.5%, so as to ensure the best catalytic performance of the multi-metal composite heteropoly acid catalyst.

[0017] The second aspect of the present invention is to provide a multi-metal composite heteropoly acid catalyst, which is prepared by the preparation method of the multi-metal composite heteropoly acid catalyst.

[0018] Another aspect of the present invention is to provide a method for preparing a resin using the multi-metal composite heteropoly acid catalyst, comprising the following steps:

[0019] (1) dissolving a reaction raw material in a solvent to obtain a solution, wherein the reaction raw material is 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester;

[0020] (2) catalyzing the solution obtained in step (1) with a multi-metal composite heteropoly acid catalyst to obtain an inorganic phase and an organic phase;

[0021] (3) The organic phase obtained in step (2) is distilled to obtain the resin 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate.

[0022] Wherein, the 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate has the structural formula of formula (I), and the 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-ylmethyl ester has the structural formula of formula (II):

[0023]

[0024] Furthermore, a packed fixed bed reactor is used for catalytic preparation of the resin.

[0025] Furthermore, in step (2), the multi-metal composite heteropoly acid catalyst is filled into a fixed bed, and the solution and 30% hydrogen peroxide are heated, mixed evenly and pressurized through the fixed bed at a temperature of 60±2° C. and a bed pressure of 0.5 MPa-1.0 MPa.

[0026] Furthermore, in step (1), the mass ratio of the reaction raw materials to the solvent is 1:10, and the solvent is any one or two of methanol, ethanol, acetonitrile, tert-butanol, and ethyl acetate; in step (2), the mass ratio of the reaction raw materials to the catalyst is 1:5 to ensure that the reaction is fully carried out.

[0027] The resin was prepared by catalysis using a packed fixed bed reactor, and the mass space velocity of the solution of the reaction raw materials passing through the fixed bed reactor was 2h -1 , where mass space velocity = raw material mass flow rate (kg·h -1 ) / catalyst mass (kg).

[0028] Furthermore, the multi-metal composite heteropolyacid catalyst is any one or more of a supported silicotungstic acid catalyst, a supported phosphomolybdic acid catalyst, a nickel-doped supported phosphomolybdic heteropolyacid catalyst, a nickel-doped supported phosphotungstic heteropolyacid catalyst, a cobalt-doped supported silicotungstic acid catalyst, and a cobalt-doped supported phosphomolybdic heteropolyacid catalyst.

[0029] Compared with the prior art, the present invention has the following technical effects:

[0030] The catalyst prepared by the catalyst preparation method provided by the present invention has excellent catalytic performance. The catalyst is applied to the preparation method of catalytically preparing 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate resin, which can greatly improve the yield of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate. The preparation process is simple, the by-products are small, and expensive raw materials do not need to be used during the reaction, thereby saving costs. The catalyst can realize efficient and continuous preparation of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic diagram of a fixed bed reactor system used in the present invention;

[0032] Figure 2 The XRD pattern of the γ-Al2O3 catalyst support prepared in Example 1;

[0033] Figure 3 The pore size distribution diagram of the γ-Al2O3 catalyst carrier prepared in Example 1;

[0034] Figure 4 is a gas chromatogram of 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester of Example 1;

[0035] Figure 5 This is a gas chromatogram of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate of Example 1.

[0036] Reference numerals:

[0037] 1. Raw material tank; 2. Fixed bed reactor; 3. Distillation tower; 4. Pressure pump. DETAILED DESCRIPTION

[0038] The following is an explanation of the embodiments of the present invention by specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this embodiment. On the contrary, the purpose of introducing the invention in conjunction with the embodiment is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0039] The specific synthesis process of the present invention is as follows, that is, the process route for synthesizing 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate from 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester is:

[0040]

[0041] The above-mentioned synthesis process of the present invention adopts Figure 1 The fixed bed reactor system shown is carried out, and the fixed bed reactor system includes a raw material tank 1, a fixed bed reactor 2 and a distillation tower 3 which are connected in sequence through pipelines, and a pressure pump 4 is arranged on the pipeline between the raw material tank 1 and the fixed bed reactor 2.

[0042] Example 1

[0043] The process route for synthesizing 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate from 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester is as follows:

[0044]

[0045] Preparation of nickel-doped supported phosphomolybdic heteropolyacid catalyst: using crystalline aluminum chloride (AlCl3·6H2O), ammonia water and isopropanol as raw materials, adding ammonia water dropwise to the aqueous solution of aluminum chloride and isopropanol at 35°C and 300RPM under strong stirring conditions, aging at 65°C for 12h and filtering to obtain a catalyst precursor, drying the precursor at 120°C in a muffle furnace for 12h, and calcining at 450°C for 4h to obtain a γ-Al2O3 carrier; weighing 10g of the carrier, and experimentally verifying that the water absorption rate of the catalyst carrier is 90%, according to its water absorption rate (9 0%) calculate and weigh the mass of phosphotungstic acid required for 10% loading, and then weigh 0.5% loading of nickel acetate, and respectively prepare them into aqueous solutions, wherein the concentration of the phosphotungstic acid solution is 225 g / L, and the concentration of the nickel acetate solution is 50 g / L, and then the phosphotungstic acid solution and the nickel acetate solution are mixed in equal volumes to form a mixed solution, and then 9 mL of the mixed solution is taken to impregnate 10 g of the carrier in equal volumes for 30 min, the impregnated catalyst is dried at room temperature for 24 h, and then the muffle furnace is heated to 450° C. and roasted for 8 h to obtain a nickel-modified supported phosphotungstic heteropoly acid catalyst.

[0046] Preparation of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate: 1 kg of raw material 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester is added to a preparation kettle, and 10 kg of solvent tert-butyl alcohol is added to the kettle, and stirring is started to mix; nickel-doped supported phosphomolybdic heteropolyacid catalyst is filled into the fixed bed layer, and heating is started to control the temperature of the fixed bed reactor to 60° C. After the temperature stabilizes, 30% hydrogen peroxide and the mixed raw materials are mixed through a mixer and then pumped into the fixed bed reactor through a pressure pump, and the fixed bed reactor is maintained at 40° C. The temperature of the reactor is 60°C and the bed pressure is 0.5MPa; after passing through the fixed bed, a product solution is obtained, and the separator is used to separate the organic phase and the inorganic phase. The inorganic phase is reduced with hydrogen peroxide and then discharged as a waste liquid, and the organic phase is sent to a distillation tower for distillation to separate the solvent tert-butyl alcohol, the unreacted raw material 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester and the product 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate, to obtain a 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate product with a purity of >98%.

[0047] Example 2

[0048] The process route for synthesizing 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate from 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester is as follows:

[0049]

[0050] Preparation of cobalt-doped supported silicotungstic acid catalyst: using crystalline aluminum chloride (AlCl3·6H2O), ammonia water and isopropanol as raw materials, ammonia water was added dropwise to the aqueous solution of aluminum chloride and isopropanol at 35°C and 300RPM under strong stirring conditions, aged at 65°C for 12h and filtered to obtain a catalyst precursor, the precursor was placed in a muffle furnace and dried at 120°C for 12h, and then calcined at 450°C for 4h to obtain a γ-Al2O3 carrier; 10g of the carrier was weighed, and 10g of the carrier was calculated according to its water absorption rate (90%) and weighed. The mass of phosphotungstic acid required for 0% loading amount, and then weigh 0.5% loading amount of cobalt nitrate, respectively configured into aqueous solutions, wherein the concentration of phosphomolybdic acid solution is 225g / L, and the concentration of nickel acetate solution is 55g / L, and then the phosphotungstic acid solution and the nickel acetate solution are mixed in equal volumes to form a mixed solution, and then 9mL of the mixed solution is taken to impregnate 10g of the carrier in equal volumes for 30min, the impregnated catalyst is dried at room temperature for 24h, and then the muffle furnace is heated to 450℃ and roasted for 8h to obtain a supported phosphotungstic heteropoly acid catalyst.

[0051] Preparation of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate: 1 kg of the raw material 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-ylmethyl ester is added to the preparation kettle, and 10 kg of solvent tert-butyl alcohol is added to the kettle, and stirring is started to mix; the cobalt-doped supported silicotungstic acid catalyst is filled into the fixed bed layer, and the heating is turned on, and the temperature of the fixed bed reactor is controlled to be 60°C. After the temperature stabilizes, 30% hydrogen peroxide and the mixed raw materials are mixed evenly through a mixer, and then pumped into the fixed bed reactor through a pressure pump, and the fixed bed is maintained. The temperature of the reactor is 60° C. and the bed pressure is 1.0 MPa. After passing through the fixed bed, a product solution is obtained, and the separator is used to separate the organic phase and the inorganic phase. The inorganic phase is reduced and treated with hydrogen peroxide and then discharged as waste liquid. The organic phase is sent to a distillation tower for distillation to separate the solvent tert-butyl alcohol, the unreacted raw material 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester and the product 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate, and obtain a 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate product with a purity of >98%.

[0052] Comparative Example 1

[0053] Preparation of a supported phosphomolybdic acid catalyst: using crystalline aluminum chloride (AlCl3·6H2O), ammonia water and isopropanol as raw materials, adding ammonia water dropwise to an aqueous solution of aluminum chloride and isopropanol at 35°C and 300RPM under strong stirring conditions, aging at 65°C for 12h and filtering to obtain a catalyst precursor, drying the precursor at 120°C in a muffle furnace for 12h, and calcining at 450°C for 4h to obtain a γ-Al2O3 carrier; weighing 10g of the carrier, calculating and weighing the mass of phosphotungstic acid required for 3% loading according to its water absorption rate, and configuring it into an aqueous solution (the concentration of phosphotungstic acid is 42g / L), then using 9mL of the aqueous solution to impregnate 10g of the carrier with an equal volume for 30min, drying the impregnated catalyst at room temperature for 24h, and then calcining the muffle furnace at 450°C for 8h to obtain a supported phosphotungstic acid catalyst.

[0054] Preparation of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate: 1 kg of raw material 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester is added to a preparation kettle, and 10 kg of solvent tert-butyl alcohol is added to the kettle, and stirring is started to mix; the supported phosphomolybdic heteropoly acid catalyst is filled into the fixed bed layer, and heating is started, and the temperature of the fixed bed reactor is controlled to be 60°C. After the temperature stabilizes, 30% hydrogen peroxide and the mixed raw materials are mixed through a mixer and then pumped into the fixed bed reactor through a pressure pump, and the temperature of the fixed bed reactor is maintained at 60°C. The temperature is 60°C and the bed pressure is 0.5MPa; after passing through the fixed bed, a product solution is obtained, and the liquid separator is used to separate the organic phase and the inorganic phase, the inorganic phase is reduced and treated with hydrogen peroxide and then discharged as a waste liquid, and the organic phase is sent to a distillation tower for distillation to separate the solvent tert-butyl alcohol, the unreacted raw material 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester and the product 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate, and obtain a 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate product with a purity of 89.44%.

[0055] Performance Testing

[0056] X-ray diffraction was used to determine the composition and structure of the γ-Al2O3 carrier. The diffraction pattern is as follows: Figure 2 As shown; low temperature nitrogen desorption (BET) was used to determine the pore size distribution of the γ-Al2O3 carrier, and the results are as follows Figure 3 As shown; gas chromatography (GC) was used to test the conversion rate and product purity of the product, wherein the gas chromatogram of 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester is shown in Figure 4 As shown; the gas chromatogram of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate is as shown Figure 5 shown.

[0057] The high-efficiency multi-metal composite heteropolyacid catalyst prepared by the catalyst preparation method of the present invention has excellent catalytic performance and is applied to the synthesis reaction of catalytic epoxidation of 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester to 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate, which can realize the continuous production of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate, and simplifies the process, has mild reaction conditions, simple post-treatment process, few by-products, high yield, reduces the intermediate steps of product synthesis, reduces costs, is environmentally friendly, and is suitable for industrial production.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a multi-metal composite heteropoly acid catalyst, characterized in that: The following steps are involved: (1) Preparation of catalyst carrier: using chemical precipitation method, aluminum source, ammonia water and isopropanol as raw materials, aging and filtering to obtain catalyst precursor, and drying and calcining the catalyst precursor to obtain γ-Al2O3 catalyst carrier; (2) Loading catalyst: weighing a certain mass of γ-Al2O3 catalyst carrier, calculating the mass of the required active component according to the water absorption rate and loading amount of the γ-Al2O3 catalyst carrier, preparing an aqueous solution of the active component, impregnating the γ-Al2O3 catalyst carrier with the aqueous solution of the active component in equal volumes, and then drying and calcining to obtain the multi-metal composite heteropoly acid catalyst; Wherein, the active component is any one or more of silicotungstic acid, phosphomolybdic acid, nickel-doped silicotungstic acid, nickel-doped phosphomolybdic acid, cobalt-doped silicotungstic acid, and cobalt-doped phosphomolybdic acid.

2. The method for preparing the multi-metal composite heteropoly acid catalyst according to claim 1, characterized in that: In step (1), crystalline aluminum chloride (AlCl3·6H2O) is used as an aluminum source, and ammonia water is added dropwise to an aqueous solution of crystalline aluminum chloride and isopropanol under stirring at 35°C, aged at 65°C for 12h, and then filtered to obtain a catalyst precursor, and the catalyst precursor is dried at 120°C for 12h, and then calcined at 450°C for 4h to obtain a γ-Al2O3 catalyst carrier.

3. The method for preparing the multi-metal composite heteropoly acid catalyst according to claim 1, characterized in that: In step (2), the loading amount of the silicotungstic acid and phosphomolybdic acid is 5-15%, and the loading amount of the nickel and cobalt is 0.3-2%.

4. The method for preparing a multi-metal composite heteropoly acid catalyst according to claim 1, characterized in that: In step (2), the impregnated catalyst is dried at room temperature for 24 h and then calcined at 450° C. for 8 h.

5. A multi-metal composite heteropoly acid catalyst, characterized in that: The catalyst is prepared by the method for preparing the multi-metal composite heteropolyacid catalyst according to any one of claims 1 to 4.

6. A method for preparing resin using the multi-metal composite heteropoly acid catalyst according to claim 5, characterized in that: The following steps are involved: (1) dissolving a reaction raw material in a solvent to obtain a solution, wherein the reaction raw material is 3,3-cyclohexene-1-carboxylic acid-3-cyclohexene-1-yl methyl ester; (2) catalyzing the solution obtained in step (1) with a multi-metal composite heteropoly acid catalyst to obtain an inorganic phase and an organic phase; (3) The organic phase obtained in step (2) is distilled to obtain the resin 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate.

7. The method for preparing resin by catalysis according to claim 6, characterized in that: A packed fixed bed reactor is used for catalytic preparation of the resin.

8. The method for preparing resin by catalysis according to claim 7, characterized in that: In step (2), the multi-metal composite heteropoly acid catalyst is filled into a fixed bed, and the solution and 30% hydrogen peroxide are heated, mixed evenly and pressurized through the fixed bed at a temperature of 60±2° C. and a bed pressure of 0.5 MPa-1.0 MPa.

9. The method for preparing resin by catalysis according to claim 6, characterized in that: In step (1), the mass ratio of the reaction raw materials to the solvent is 1:10, and the solvent is any one or two of methanol, ethanol, acetonitrile, tert-butanol, and ethyl acetate; in step (2), the mass ratio of the reaction raw materials to the catalyst is 1:

5.

10. The method for preparing resin by catalysis according to any one of claims 6 to 9, characterized in that: The multi-metal composite heteropolyacid catalyst is any one or more of a supported silicotungstic acid catalyst, a supported phosphomolybdic acid catalyst, a nickel-doped supported phosphomolybdic heteropolyacid catalyst, a nickel-doped supported phosphotungstic heteropolyacid catalyst, a cobalt-doped supported silicotungstic acid catalyst, and a cobalt-doped supported phosphomolybdic heteropolyacid catalyst.

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