A resin catalyst for the synthesis of CPME, its preparation method and application

Abstract

This invention discloses a resin catalyst for the synthesis of CPME, its preparation method, and its application, belonging to the field of fine chemical catalysis technology. The method includes the following steps: using styrene, divinylbenzene, and 4-vinylcyclohexene as monomers, suspension copolymerization is carried out in the presence of a porogen, dispersant, initiator, and aqueous phase inhibitor to obtain copolymer white spheres. These spheres are then extracted, dried, sieved, sulfonated with sulfur trioxide, and washed to obtain the product. This invention introduces a third monomer, 4-vinylcyclohexene, into the traditional styrene-divinylbenzene copolymer system. This rigid cyclic structure significantly enhances the thermal stability of the resin skeleton. Simultaneously, the use of a special dispersant, in which perfluorinated segments can oriented to the surface of the resin particles during polymerization to form a hydrophobic protective layer, significantly improves the stability of the catalyst and the selectivity for cyclopentene at higher temperatures.

Description

Technical Field

[0001] This invention belongs to the field of fine chemical catalysis technology, and relates to a resin catalyst for the synthesis of CPME, its preparation method and application. Background Technology

[0002] Amid the global trend of green and refined transformation in the chemical industry, the development of environmentally friendly solvents and efficient synthesis processes has become a focus of attention for both academia and industry. Cyclopentyl methyl ether (CPME), as an emerging green solvent, has shown broad application prospects in pharmaceuticals, electronic chemicals, and high-end coatings due to its unique physicochemical properties and safety and environmental advantages. However, its industrial production still faces bottlenecks such as low efficiency, heavy pollution, and high cost of traditional synthesis processes, which restricts further expansion of the market.

[0003] The current CPME synthesis process mainly employs the liquid-phase etherification reaction of cyclopentene and methanol under strong acid catalysis. While this technical route has been industrialized, it suffers from several drawbacks. First, traditional homogeneous catalysts such as concentrated sulfuric acid and p-toluenesulfonic acid, although achieving high conversion rates (>90%), suffer from severe equipment wear due to their strong corrosiveness and generate large amounts of acidic wastewater, with treatment costs accounting for over 30% of total production costs. Second, solid acid catalysts such as molecular sieves and heteropoly acids, while recyclable, are easily deactivated by water molecules generated during the reaction, leading to high energy consumption during regeneration. Furthermore, the azeotropic system formed by CPME, unreacted methanol, and water in the reaction system necessitates multi-stage distillation for product separation, accounting for up to 40% of energy consumption and severely weakening the process's economic viability. More importantly, the cyclopentene dimer generated by the side reaction not only reduces product purity but also wastes raw materials. These technical shortcomings collectively contribute to the high production costs of existing CPME, limiting its market penetration.

[0004] Based on this, this invention focuses on the etherification reaction system of cyclopentene and methanol, with the development of high-performance resin catalysts as the core, to construct a new efficient and clean CPME synthesis process. It aims to break through existing technical barriers, promote the localization of this high value-added chemical, and provide innovative solutions for the sustainable development of my country's fine chemical industry.

[0005] Therefore, how to develop a resin catalyst for the synthesis of CPME, its preparation method, and its application are problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides a resin catalyst for the synthesis of CPME, its preparation method and application.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A method for preparing a resin catalyst for the synthesis of CPME includes the following steps:

[0009] Styrene, divinylbenzene and 4-vinylcyclohexene were used as monomers, and copolymerized in suspension in the presence of porogen, dispersant, initiator and aqueous phase inhibitor to obtain copolymer white spheres. The copolymer white spheres were then extracted, dried and sieved, sulfonated in a sulfur trioxide chloroethane solution or a sulfur trioxide dichloropropylene solution and washed to obtain the resin catalyst for synthesizing CPME.

[0010] The pore-forming agent is a mixture of n-heptane and perfluorohexane;

[0011] The dispersant is poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate) (PSMA-b-PFOEA);

[0012] The synthesis process of the poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate) is as follows: Under nitrogen protection, styrene, maleic anhydride, 2-cyano-2-propyldodecyl trithiocarbonate and azobisisobutyronitrile are dissolved in anhydrous tetrahydrofuran and reacted at 70°C for 12 hours to generate macromolecular chain transfer agent P(St-alt-MA). Then, 2-(perfluorooctyl)ethyl acrylate and azobisisobutyronitrile are added, and the temperature is raised to 80°C and the reaction is continued for 24 hours to obtain the poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate).

[0013] The initiator is benzoyl peroxide;

[0014] The aqueous polymerization inhibitor is methylene blue.

[0015] Further, the preparation method of the copolymer white spheres includes the following steps: styrene, divinylbenzene, 4-vinylcyclohexene, pore-forming agent, dispersant, and initiator are added to a mixing tank and stirred for 1-4 hours to ensure uniform mixing and obtain an oil phase. Water and an aqueous phase polymerization inhibitor are added to a polymerization reactor, and the mixture is stirred and heated to 40-50°C to completely dissolve the aqueous phase polymerization inhibitor. The obtained oil phase is then added, and the stirring speed is adjusted to 120-150 rpm. The temperature is slowly increased to 80°C for polymerization. After reacting for 10-20 hours, the mixture is cooled and discharged. The polymer is washed three times with hot water and cold water respectively to separate the copolymer white spheres. The weight parts of each raw material are:

[0016] 80-100 parts of styrene

[0017] 10-20 parts of divinylbenzene

[0018] 5-10 parts of 4-vinylcyclohexene

[0019] 5-10 parts of n-heptane,

[0020] 5-10 parts of perfluorohexane

[0021] 3-6 parts dispersant

[0022] Initiator 0.5-1 part,

[0023] 0.5-1 part of aqueous polymerization inhibitor,

[0024] 400-500 parts water.

[0025] Furthermore, the addition of styrene, divinylbenzene, 4-vinylcyclohexene, porogen, dispersant, and initiator to the mixing tank is carried out at a stirring speed of 100-150 rpm;

[0026] The stirring speed for adding water and aqueous phase polymerization inhibitor into the polymerization reactor is 100-150 rpm, and the stirring time is 2-4 hours.

[0027] The slow heating rate is 20°C / h.

[0028] Furthermore, the extraction method includes the following steps:

[0029] Add the copolymer white spheres to the extraction vessel, add excess solvent to the distillation vessel and heat it to evaporate the solvent in the distillation vessel. The solvent then condenses and flows into the extraction vessel, where it partially dissolves the porogen in the extraction vessel. The resulting mixed solution remains in the extraction vessel. When the liquid level in the extraction vessel reaches a certain height, return the mixed solution to the distillation vessel and heat the distillation vessel again to evaporate the solvent. Repeat this process 10-15 times to completely extract the porogen from the white spheres.

[0030] Furthermore, the solvent is toluene, the mass ratio of copolymer white spheres to solvent is 1:(5-10), and the heating temperature is 110℃.

[0031] Furthermore, the drying and sieving method includes the following steps:

[0032] The extracted copolymer white spheres were placed in a ventilated area for 24 hours to allow most of the residual solvent to evaporate. The copolymer white spheres were then dried to a moisture content of 5-10%, sieved, and the copolymer white spheres with a particle size of 0.6-0.9 mm were taken as the sulfonation matrix.

[0033] Furthermore, the sulfonation and washing method includes the following steps:

[0034] The copolymer white spheres were immersed in a sulfur trioxide solution in chloroethane or a sulfur trioxide solution in dichloropropylene and stirred for 1-4 hours to ensure thorough mixing of the white spheres and sulfur trioxide. The mass ratio of the copolymer white spheres to sulfur trioxide was 1:(5-10). The reaction temperature was then controlled at 100-120℃ for 10-20 hours. After the reaction was stopped and cooled, the resin product was transferred to a water washing column and washed with a large amount of deionized water until neutral. The resin with a water content of 50% was separated to obtain the resin catalyst for the synthesis of CPME.

[0035] Furthermore, the copolymer white balls are immersed in a sulfur trioxide-chloroethane solution or a sulfur trioxide-dichloropropylene solution and stirred at a speed of 100-150 rpm.

[0036] The present invention also provides a resin catalyst for the synthesis of CPME prepared by the method described above.

[0037] The present invention also provides the application of the resin catalyst for synthesizing CPME in the synthesis of CPME.

[0038] The beneficial effects of this invention are as follows: The purpose of this invention is to innovate a technological path centered on functionalized resin catalysts. Compared with traditional catalysts, sulfonic acid-type cation exchange resins have unique advantages such as uniform distribution of acidic sites, high mechanical strength, and adjustable surface hydrophobicity. Through hydrophobic modification, the adsorption of water molecules on the catalyst surface can be effectively suppressed, alleviating the problem of active site poisoning. The catalyst of this invention is mainly applied to the liquid-phase etherification reaction system of cyclopentene and methanol. This invention provides a high-performance resin catalyst for the synthesis of cyclopentyl methyl ether and its preparation method. An innovative monomer combination and dispersant system are used to achieve precise control of the catalyst's high-temperature resistance and acid-hydrophobicity. This invention introduces a third monomer, 4-vinylcyclohexene (5-8% of the total monomer content), into the traditional styrene-divinylbenzene copolymer system. This rigid cyclic structure significantly enhances the thermal stability of the resin skeleton. Simultaneously, a special dispersant, poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate) (PSMA-b-PFOEA), is used. The perfluorinated segments in this dispersant can oriented to the surface of the resin particles during polymerization, forming a hydrophobic protective layer. This significantly improves the stability of the catalyst and the selectivity for cyclopentene at higher temperatures. Detailed Implementation

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] The dispersant of this invention is poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate). The synthesis process is as follows: Under nitrogen protection, styrene (10.4 g, 100 mmol), maleic anhydride (9.8 g, 100 mmol), 2-cyano-2-propyldodecyl trithiocarbonate (CPDT, 0.28 g, 0.8 mmol), and azobisisobutyronitrile (13.1 mg, 0.08 mmol) are dissolved in 40 mL of anhydrous tetrahydrofuran, and reacted at 70 °C for 12 hours to generate the macromolecular chain transfer agent P(St-alt-MA) (M = 12,500 Da). Then, 2-(perfluorooctyl)ethyl acrylate (25.6 g, 40 mmol) and additional azobisisobutyronitrile (6.6 mg, 0.04 mmol) were added, and the mixture was heated to 80 °C and reacted for another 24 hours to obtain poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate).

[0041] Example 1

[0042] A method for preparing a resin catalyst for the synthesis of CPME includes the following steps:

[0043] (1) Weigh out 80 grams of styrene.

[0044] 10 grams of divinylbenzene

[0045] 5 grams of 4-vinylcyclohexene

[0046] 5 grams of n-heptane as a pore-forming agent

[0047] 5 grams of perfluorohexane as a pore-forming agent

[0048] 3 grams of dispersant, the dispersant being poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate),

[0049] 0.5 g of initiator, the initiator being benzoyl peroxide.

[0050] 0.5 g of aqueous polymerization inhibitor, which is methylene blue.

[0051] 400 grams of water;

[0052] (2) Styrene, divinylbenzene, 4-vinylcyclohexene, pore-forming agent, dispersant and initiator were added to a mixing tank and stirred for 1 hour at a stirring speed of 100 rpm to make the liquid mixture uniform and obtain an oil phase. Water and aqueous phase polymerization inhibitor were added to the polymerization reactor and stirred and heated to 40°C to completely dissolve the aqueous phase polymerization inhibitor. The stirring speed was 100 rpm and the stirring time was 2 hours. Then the obtained oil phase was added, the stirring speed was adjusted to 120 rpm, and the temperature was slowly raised to 80°C for polymerization at a heating rate of 20°C / h. After reacting for 10 hours, the mixture was cooled and discharged. The polymer was washed three times with hot water and cold water respectively to separate the copolymer white balls.

[0053] (3) Add the copolymer white balls to the extraction vessel, add toluene to the distillation vessel, and heat to 110°C with a mass ratio of white balls to toluene of 1:5. The solvent in the distillation vessel will evaporate and flow into the extraction vessel after condensation. The solvent will partially dissolve the porogen in the extraction vessel, and the resulting mixed solution will remain in the extraction vessel. When the liquid level in the extraction vessel reaches 2 / 3 of the liquid level, the mixed solution will be returned to the distillation vessel, and the distillation vessel will be heated again to evaporate the solvent. Repeat this process 10 times to completely extract the porogen in the white balls.

[0054] (4) Place the extracted copolymer white balls in a ventilated place for 24 hours to allow most of the residual solvent to evaporate. Dry the copolymer white balls to a moisture content of 5-10%, sieve them, and take copolymer white balls with a particle size of 0.6-0.9 mm as sulfonation matrix.

[0055] (5) The copolymer white balls were immersed in a chloroethane solution with a sulfur trioxide mass concentration of 30% and stirred for 1.0 h at a stirring speed of 100 rpm to ensure that the white balls and sulfur trioxide were fully mixed. The mass ratio of the copolymer white balls to sulfur trioxide was 1:5. Then the reaction temperature was controlled at 100℃ and the reaction was carried out for 10 h. The reaction was then stopped, cooled, and the resin product was transferred to a water washing column and washed with a large amount of deionized water until neutral. The resin with a water content of 50% was separated to obtain the resin catalyst for synthesizing CPME.

[0056] The resin catalyst used in this embodiment for the synthesis of cyclopentyl methyl ether was applied under the following conditions: reaction temperature 120°C, pressure 1.5 MPa, and space velocity 0.5 h⁻¹. -1 Under operating conditions of an alcohol-to-olefin molar ratio of 1.2:1, the conversion of cyclopentene was 49.3%, and the selectivity for cyclopentyl methyl ether was 96.8%.

[0057] Example 2

[0058] A method for preparing a resin catalyst for the synthesis of CPME includes the following steps:

[0059] (1) Weigh out 100 grams of styrene.

[0060] 20 grams of divinylbenzene

[0061] 10 grams of 4-vinylcyclohexene

[0062] 10 grams of n-heptane as a pore-forming agent

[0063] 10 grams of perfluorohexane as a pore-forming agent

[0064] 6 grams of dispersant, the dispersant being poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate),

[0065] 1 gram of initiator, the initiator being benzoyl peroxide.

[0066] 1 gram of aqueous polymerization inhibitor, which is methylene blue.

[0067] 500 grams of water;

[0068] (2) Styrene, divinylbenzene, 4-vinylcyclohexene, pore-forming agent, dispersant and initiator were added to a mixing tank and stirred for 4 hours at a stirring speed of 150 rpm to make the liquid mixture uniform and obtain an oil phase. Water and aqueous phase polymerization inhibitor were added to the polymerization reactor and stirred and heated to 50°C to completely dissolve the aqueous phase polymerization inhibitor. The stirring speed was 150 rpm and the stirring time was 4 hours. Then the obtained oil phase was added, the stirring speed was adjusted to 150 rpm, and the temperature was slowly raised to 80°C for polymerization at a heating rate of 20°C / h. After reacting for 20 hours, the mixture was cooled and discharged. The polymer was washed three times with hot water and cold water respectively to separate the copolymer white balls.

[0069] (3) Add the copolymer white balls to the extraction vessel, add toluene to the distillation vessel, the mass ratio of white balls to toluene is 1:10, heat to 110°C, so that the solvent in the distillation vessel evaporates and flows into the extraction vessel after condensation. The solvent dissolves part of the porogen in the extraction vessel, and the resulting mixed solution remains in the extraction vessel. When the liquid level in the extraction vessel reaches 2 / 3 of the liquid level, put the mixed solution back into the distillation vessel, heat the distillation vessel again to evaporate the solvent, and repeat this process 15 times to extract the porogen in the white balls.

[0070] (4) Place the extracted copolymer white balls in a ventilated place for 24 hours to allow most of the residual solvent to evaporate. Dry the copolymer white balls to a moisture content of 5-10%, sieve them, and take copolymer white balls with a particle size of 0.6-0.9 mm as sulfonation matrix.

[0071] (5) The copolymer white balls were immersed in a 20% sulfur trioxide solution of dichloropropylene and stirred for 4 hours at a stirring speed of 150 rpm to ensure that the white balls and sulfur trioxide were fully mixed. The mass ratio of the copolymer white balls to sulfur trioxide was 1:10. The reaction temperature was then controlled at 120℃ and the reaction was carried out for 12 hours. The reaction was then stopped and cooled. The resin product was transferred to a water washing column and washed with a large amount of deionized water until neutral. The resin with a water content of 56% was separated to obtain the resin catalyst for synthesizing CPME.

[0072] The resin catalyst involved in this embodiment was applied to the synthesis of cyclopentyl methyl ether under the following conditions: reaction temperature 130°C, pressure 3.0 MPa, and space velocity 1.0 h⁻¹. -1 Under operating conditions of an alcohol-to-olefin molar ratio of 2.0:1, the conversion of cyclopentene was 48.7%, and the selectivity for cyclopentyl methyl ether was 97.3%.

[0073] Example 3

[0074] A method for preparing a resin catalyst for the synthesis of CPME includes the following steps:

[0075] (1) Weigh out 90 grams of styrene.

[0076] 15 grams of divinylbenzene

[0077] 8 grams of 4-vinylcyclohexene

[0078] 7 grams of n-heptane, a pore-forming agent

[0079] 8 grams of perfluorohexane as a pore-forming agent

[0080] 5 grams of dispersant, the dispersant being poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate),

[0081] 0.7 g of initiator, the initiator being benzoyl peroxide.

[0082] 0.8 g of aqueous polymerization inhibitor, which is methylene blue.

[0083] 450 grams of water;

[0084] (2) Styrene, divinylbenzene, 4-vinylcyclohexene, pore-forming agent, dispersant and initiator were added to a mixing tank and stirred for 3 hours at a stirring speed of 120 rpm to make the liquid mixture uniform and obtain an oil phase. Water and aqueous phase polymerization inhibitor were added to the polymerization reactor and stirred and heated to 45°C to completely dissolve the aqueous phase polymerization inhibitor. The stirring speed was 120 rpm and the stirring time was 3 hours. Then the obtained oil phase was added, the stirring speed was adjusted to 130 rpm, and the temperature was slowly raised to 80°C for polymerization at a heating rate of 20°C / h. After reacting for 15 hours, the mixture was cooled and discharged. The polymer was washed three times with hot water and cold water respectively to separate the copolymer white balls.

[0085] (3) Add the copolymer white balls to the extraction vessel, add toluene to the distillation vessel, the mass ratio of white balls to toluene is 1:8, heat to 110°C, so that the solvent in the distillation vessel evaporates and flows into the extraction vessel after condensation. The solvent dissolves part of the porogen in the extraction vessel, and the resulting mixed solution remains in the extraction vessel. When the liquid level in the extraction vessel reaches 2 / 3 of the liquid level, put the mixed solution back into the distillation vessel, heat the distillation vessel again to evaporate the solvent, and repeat this process 12 times to extract the porogen in the white balls.

[0086] (4) Place the extracted copolymer white balls in a ventilated place for 24 hours to allow most of the residual solvent to evaporate. Dry the copolymer white balls to a moisture content of 5-10%, sieve them, and take copolymer white balls with a particle size of 0.6-0.9 mm as sulfonation matrix.

[0087] (5) The copolymer white balls were immersed in a chloroethane solution with a sulfur trioxide mass concentration of 25% and stirred for 2 hours at a stirring speed of 120 rpm to ensure that the white balls and sulfur trioxide were fully mixed. The mass ratio of the copolymer white balls to sulfur trioxide was 1:8. The reaction temperature was then controlled at 110℃ and the reaction was carried out for 15 hours. The reaction was then stopped and cooled. The resin product was transferred to a water washing column and washed with a large amount of deionized water until neutral. The resin with a water content of 54% was separated to obtain the resin catalyst for the synthesis of CPME.

[0088] The resin catalyst used in this embodiment for the synthesis of cyclopentyl methyl ether was applied under the following conditions: reaction temperature 125°C, pressure 2.0 MPa, and space velocity 0.8 h⁻¹. -1 Under operating conditions of an alcohol-to-olefin molar ratio of 1.5:1, the conversion of cyclopentene was 46.6%, and the selectivity for cyclopentyl methyl ether was 95.4%.

[0089] Comparative Example 1

[0090] Using commercially available macroporous strong acid cation exchange resin catalyst A15 under the conditions of Example 1 (reaction temperature 120°C, pressure 1.5 MPa, space velocity 0.5 h⁻¹, alcohol-to-olefin molar ratio 1.2:1), the conversion of cyclopentene was 34.7%, and the selectivity for cyclopentyl methyl ether was 91.4%.

[0091] Comparative Example 2

[0092] Using commercially available macroporous strong acid cation exchange resin catalyst D005 under the conditions of Example 2—reaction temperature 130°C, pressure 3.0 MPa, space velocity 1.0 h⁻¹, and alcohol-to-olefin molar ratio 2.0:1—the conversion of cyclopentene was 29.7%, and the selectivity for cyclopentyl methyl ether was 95.8%.

[0093] The description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a resin catalyst for synthesizing CPME, characterized by, Includes the following steps: Styrene, divinylbenzene and 4-vinylcyclohexene were used as monomers, and copolymerized in suspension in the presence of porogen, dispersant, initiator and aqueous phase inhibitor to obtain copolymer white spheres. The copolymer white spheres were then extracted, dried and sieved, sulfonated in a sulfur trioxide chloroethane solution or a sulfur trioxide dichloropropylene solution and washed to obtain the resin catalyst for synthesizing CPME. The pore-forming agent is a mixture of n-heptane and perfluorohexane; The dispersant is poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate); The synthesis process of the poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate) is as follows: Under nitrogen protection, styrene, maleic anhydride, 2-cyano-2-propyldodecyl trithiocarbonate and azobisisobutyronitrile are dissolved in anhydrous tetrahydrofuran and reacted at 70°C for 12 hours to generate macromolecular chain transfer agent P(St-alt-MA). Then, 2-(perfluorooctyl)ethyl acrylate and azobisisobutyronitrile are added, and the temperature is raised to 80°C and the reaction is continued for 24 hours to obtain the poly(styrene-alt-maleic anhydride)-block-poly(2-(perfluorooctyl)ethyl acrylate). The initiator is benzoyl peroxide; The aqueous polymerization inhibitor is methylene blue; The weight proportions of each raw material are as follows: 80-100 parts of styrene 10-20 parts of divinylbenzene 5-10 parts of 4-vinylcyclohexene 5-10 parts of n-heptane, 5-10 parts of perfluorohexane 3-6 parts dispersant Initiator 0.5-1 part, 0.5-1 part of aqueous polymerization inhibitor, 400-500 portions of water.

2. A process for the preparation of a resin catalyst for the synthesis of CPME according to claim 1, characterized by, The preparation method of the copolymer white spheres includes the following steps: styrene, divinylbenzene, 4-vinylcyclohexene, porogen, dispersant and initiator are added to a mixing tank and stirred for 1-4 hours to make the liquid mixture uniform and obtain an oil phase. Water and an aqueous phase polymerization inhibitor are added to the polymerization reactor, and the mixture is stirred and heated to 40-50°C to completely dissolve the aqueous phase polymerization inhibitor. Then the obtained oil phase is added, the stirring speed is adjusted to 120 rpm-150 rpm, and the temperature is slowly raised to 80°C for polymerization. After reacting for 10-20 hours, the mixture is cooled, discharged, and the polymer is washed three times with hot water and cold water respectively to separate the copolymer white spheres.

3. The process for the preparation of a resin catalyst for the synthesis of CPME according to claim 2, characterized in that, The process involves adding styrene, divinylbenzene, 4-vinylcyclohexene, porogen, dispersant, and initiator into a mixing tank and stirring at a speed of 100-150 rpm. The stirring speed for adding water and aqueous phase polymerization inhibitor into the polymerization reactor is 100-150 rpm, and the stirring time is 2-4 hours. The slow heating rate is 20°C / h.

4. The process for the preparation of a resin catalyst for the synthesis of CPME according to claim 1, characterized in that, The extraction method includes the following steps: Add the copolymer white spheres to the extraction vessel, add excess solvent to the distillation vessel and heat it to evaporate the solvent in the distillation vessel. The solvent then condenses and flows into the extraction vessel, where it partially dissolves the porogen in the extraction vessel. The resulting mixed solution remains in the extraction vessel. When the liquid level in the extraction vessel reaches a certain height, return the mixed solution to the distillation vessel and heat the distillation vessel again to evaporate the solvent. Repeat this process 10-15 times to completely extract the porogen from the white spheres.

5. The process for the preparation of a resin catalyst for the synthesis of CPME according to claim 4, characterized in that, The solvent is toluene, the mass ratio of copolymer white spheres to solvent is 1:(5-10), and the heating temperature is 110℃.

6. The process for the preparation of a resin catalyst for the synthesis of CPME according to claim 1, characterized by the fact that, The drying and sieving method includes the following steps: The extracted copolymer white spheres were placed in a ventilated area for 24 hours to allow most of the residual solvent to evaporate. The copolymer white spheres were then dried to a moisture content of 5-10%, sieved, and the copolymer white spheres with a particle size of 0.6-0.9 mm were taken as the sulfonation matrix.

7. The process for the preparation of a resin catalyst for the synthesis of CPME according to claim 1, characterized by the fact that, The sulfonation and washing method includes the following steps: The copolymer white spheres were immersed in a sulfur trioxide solution in chloroethane or a sulfur trioxide solution in dichloropropylene and stirred for 1-4 hours to ensure thorough mixing of the white spheres and sulfur trioxide. The mass ratio of the copolymer white spheres to sulfur trioxide was 1:(5-10). The reaction temperature was then controlled at 100-120℃ for 10-20 hours. After the reaction was stopped and cooled, the resin product was transferred to a water washing column and washed with a large amount of deionized water until neutral. The resin with a water content of 50%-56% was separated to obtain the resin catalyst for the synthesis of CPME.

8. The process for the preparation of a resin catalyst for the synthesis of CPME according to claim 1, characterized by the fact that, The copolymer white balls were immersed in a sulfur trioxide-chloroethane solution or a sulfur trioxide-dichloropropylene solution and stirred at a speed of 100-150 rpm.

9. A resin catalyst for synthesizing CPME prepared by the method according to any one of claims 1-8.

10. The use of the resin catalyst for synthesizing CPME as described in claim 9 in the synthesis of CPME.