Preparation method and application of a supported cerium hydroxyl chloride catalyst

Abstract

This invention relates to a method for preparing and applying a supported cerium hydroxide catalyst. The method employs a "mid-stage intervention" approach: after Ce(OH)₂Cl crystal nuclei have formed but before they have grown into micron-sized crystals (after heating and reflux for 30-120 min in step (1)), a silicon-based support is added. The surface confinement effect of the support prevents further crystal growth, thereby obtaining a highly dispersed, small-sized supported Ce(OH)₂Cl catalyst, significantly increasing the number of catalytic sites. This invention eliminates the need for toxic organic reagents. The prepared supported cerium hydroxide catalyst exhibits excellent catalytic activity in the carbon dioxide cycloaddition reaction and demonstrates catalytic universality for various epoxy substrates, with corresponding cyclic carbonate yields not less than 94% and selectivity not less than 99%.

Description

Technical Field

[0001] This invention belongs to the field of catalytic materials and carbon dioxide resource utilization technology, specifically relating to a supported cerium hydroxychloride catalyst and its preparation method, as well as the application of the catalyst in the preparation of cyclic carbonates by carbon dioxide cycloaddition reaction. Background Technology

[0002] The cycloaddition reaction of carbon dioxide (CO2) with epoxides is an important pathway for the resource utilization of CO2. The resulting cyclic carbonates are widely used as polar solvents, lithium-ion battery electrolytes, and polycarbonate precursors. Currently, homogeneous catalysts such as quaternary ammonium salts and ionic liquids are mainly used in industry. Although they have high activity, they suffer from difficulties in product separation and catalyst recovery. Heterogeneous metal oxide catalysts are easier to separate, but generally have low catalytic efficiency. They usually require the addition of homogeneous halogen-containing co-catalysts (such as tetrabutylammonium bromide) to exhibit higher activity, which increases the difficulty of product separation and purification.

[0003] Our research group previously disclosed a Zr-doped CeO2 nanorod catalyst in patent CN114957192A, which achieved halogen-free catalytic CO2 cycloaddition reaction, but under harsh conditions (150℃, 6 MPa, 24 h). To address this issue, some studies have proposed strategies to immobilize halide ions in metal oxides, designing highly efficient heterogeneous catalyst metal halide oxides to avoid halogen leaching and the use of homogeneous halogen-containing promoters. Currently, various halide-containing metal oxide catalysts for CO2 cycloaddition reactions have been reported, such as FeOCl (Chemical Science, 2023, 14, 1397-1402.) and BiOBr (Journal of Materials Science & Technology, 2024, 202: 39-49.). Cerium hydroxychloride (Ce(OH)2Cl) is a catalyst whose surface simultaneously contains Ce-OH and Cl-. - The compound (Journal of Materials Chemistry C, 2017, 5(2): 444-451.) has good application potential. However, existing studies mainly focus on its crystal structure characterization and luminescence performance regulation, and there are no reports of its direct use in catalyzing the CO2 cycloaddition reaction. At the same time, the pure phase Ce(OH)2Cl crystal has a large size and low specific surface area, resulting in insufficient exposure of active sites, which limits its catalytic efficiency.

[0004] CN120361925A discloses a bromide-intercalated magnesium-aluminum layered hydroxide catalyst. 0.2 g of the catalyst (5 mmol propylene oxide) reacted at 80 °C under 2 MPa CO2 for 12 h to obtain propylene carbonate with a yield of 93.1% and a selectivity of 98.6%. Compared to halogen-free metal oxide systems, this catalyst exhibits better catalytic activity, but the catalyst dosage is relatively high, resulting in a lower number of active sites per unit mass of catalyst.

[0005] Given the current state of research, it is of great significance to develop a heterogeneous catalyst that is easy to synthesize, has high utilization of active sites, and does not require additional halogenated co-catalysts, in order to achieve efficient preparation of cyclic carbonates from the cycloaddition reaction of carbon dioxide and epoxides. Summary of the Invention

[0006] The purpose of this invention is to address the problems of low activity of metal oxides in current carbon dioxide cycloaddition reactions, the need for co-catalysts to enhance activity which is detrimental to product separation, and the inefficient utilization of catalytic active sites. This invention provides a supported cerium hydroxide catalyst, its preparation method, and its application. The method employs a "mid-stage intervention" approach: after Ce(OH)₂Cl crystal nuclei have formed but before they have grown into micron-sized crystals (after heating and reflux for 30-120 min in step (1)), a silicon-based support is added. The surface confinement effect of the support prevents further crystal growth, thereby obtaining a highly dispersed, small-sized supported Ce(OH)₂Cl catalyst.

[0007] The specific technical solution of this invention is as follows: A method for preparing a supported cerium hydroxychloride catalyst includes the following steps: (1) Dissolve chloride salt, alkali and cerium salt in deionized water and reflux at 45-95℃ for 30-120 min with stirring; The molar ratio of chloride salt, alkali, and cerium salt is (10-30):(1-5):1; (2) Add a silicon-based support to the reaction solution of step (1) and continue to stir and reflux at 45-95℃ for 3-12 h; Each 10 mmol of cerium salt corresponds to 0.5-6.0 g of silicon-based support; (3) Filter the reaction mixture obtained in step (2), collect the solid powder, wash it several times with water and ethanol, and then dry it under vacuum; (4) The dried product obtained in step (3) is heated to 200-300℃ and calcined for 1-5 h under an inert atmosphere to obtain a supported cerium hydroxychloride catalyst.

[0008] The chloride salt mentioned in step (1) is sodium chloride or potassium chloride; The alkali is hexamethylenetetramine, ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate, ammonium bicarbonate, sodium bicarbonate, potassium carbonate, or potassium bicarbonate. The cerium salt is one of hydrated cerium chloride, hydrated cerium nitrate, or hydrated cerium sulfate.

[0009] In step (1), 5-20 mmol of cerium salt is added to every 100 mL of deionized water; In step (1), the stirring speed is 300-600 rpm.

[0010] The silicon-based support mentioned in step (2) is one of fumed silica, molecular sieve or porous silica gel.

[0011] In step (3), the vacuum drying temperature is 60-80℃ and the time is 12-24 h.

[0012] The inert atmosphere mentioned in step (4) is argon, nitrogen or helium.

[0013] In step (4), the heating rate is 2-10 ℃ / min.

[0014] The catalyst has a specific surface area of ​​70-300 m². 2 / g.

[0015] The application of the supported cerium hydroxychloride catalyst prepared by the above method in the catalytic cycloaddition reaction of CO2 to prepare cyclic carbonates.

[0016] The specific steps are as follows: add the epoxide and the catalyst of this invention into a high-pressure reactor, introduce CO2, react at 0.5-3 MPa and 80-160℃ for 1-6 h, and after the reaction is completed, cool to below 10℃ and depressurize to obtain cyclic carbonate.

[0017] The epoxides include, but are not limited to, ethylene oxide, propylene oxide, butane oxide, epichlorohydrin, styrene oxide, or allyl glycidyl ether.

[0018] Add 50-150 mg of supported cerium hydroxychloride catalyst per milliliter of epoxide.

[0019] The reaction is carried out in the presence of a polar aprotic solvent with a volume ratio of solvent to epoxide of (1-10):1. The polar aprotic solvents include N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), dimethyl sulfoxide (DMSO), or N-methylpyrrolidone (NMP).

[0020] The present invention has the following beneficial effects: (1) This invention proposes a “mid-term intervention” loading strategy, which adds a support after Ce(OH)2Cl crystal nuclei are formed and grown to a certain stage. This not only preserves the ordered layered structure of Ce(OH)2Cl, but also achieves high dispersion and exposure of active sites, thus solving the problems of large crystal size and insufficient exposure of active sites in pure phase Ce(OH)2Cl. Figure 1 This indicates that the ordered layered structure of Ce(OH)₂Cl is retained. Figure 3 This demonstrates that the load limits the crystal size and achieves the dispersion effect.

[0021] (2) The supported cerium hydroxychloride catalyst prepared in this invention can efficiently catalyze the cycloaddition reaction of CO2 with various epoxides without the need for an external homogeneous halogen-containing co-catalyst. Experimental results show that under the conditions of 150℃, 1.5 MPa CO2, and 4 hours of reaction, the yield of butenyl carbonate with 0.4Ce(OH)2Cl / SiO2 can reach 94% and the selectivity is 99%, which is significantly higher than the activity (53%) of unsupported Ce(OH)2Cl. The loading process improves both the number of active sites and the catalytic effect. Under the same conditions, after 1 hour of reaction, compared with the activity of a physical mixture of Ce(OH)2Cl and SiO2 (only 9%), the yield of Ce(OH)2Cl / SiO2 is as high as 69%, indicating that the catalytic effect of the "mid-process intervention" loading strategy is significantly better than that of the conventional loading method.

[0022] (3) In this invention, the Si-O-Ce interface between the support SiO2 and Ce(OH)2Cl, through electronic regulation, enables the Ce species to be Ce 3+ / Ce 4+ Coexistence (Ce in 0.4Ce(OH)2Cl / SiO2 in X-ray photoelectron spectroscopy) 3+ With a concentration of 61.73%, the Lewis acidity of Ce species was enhanced, further improving catalytic activity. The Si-OH groups on the surface of the SiO2 support participate in the activation of the epoxide through hydrogen bonding, interacting with the Ce-OH and Cl groups of Ce(OH)2Cl. - The formation of multiple sites for synergistic catalysis produces a synergistic effect that cannot be achieved by conventional loading methods.

[0023] (4) The preparation method of the present invention has low raw material cost (sodium chloride and hexamethylenetetramine are bulk chemicals), simple synthesis process (only one step of atmospheric pressure reflux and short-time calcination is required), no need to use toxic organic reagents, and is suitable for large-scale industrial production.

[0024] (5) The supported cerium hydroxychloride catalyst prepared in this invention has catalytic universality for a variety of epoxy substrates. Experimental results show that the catalyst exhibits good catalytic performance for substrates such as propylene oxide, epibutylene oxide, epichlorohydrin, and styrene oxide, with corresponding cyclic carbonate yields of not less than 94% and selectivity of not less than 99%. Attached Figure Description

[0025] Figure 1 The X-ray diffraction patterns of Ce(OH)₂Cl, 2.3Ce(OH)₂Cl / SiO₂, 0.8Ce(OH)₂Cl / SiO₂, 0.4Ce(OH)₂Cl / SiO₂ and 0.2Ce(OH)₂Cl / SiO₂ obtained in Examples 1-5 are shown below. Figure 2 Scanning electron microscope images of 2.3Ce(OH)2Cl / SiO2, 0.8Ce(OH)2Cl / SiO2, 0.4Ce(OH)2Cl / SiO2 and 0.2Ce(OH)2Cl / SiO2 obtained in Examples 2-5; Figure 3 Transmission electron microscope images of Ce(OH)₂Cl and 0.4Ce(OH)₂Cl / SiO₂ obtained in Examples 1 and 4; Figure 4 The X-ray photoelectron spectra of Ce(OH)2Cl and 0.4Ce(OH)2Cl / SiO2 obtained in Examples 1 and 4 are shown. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. It should be noted that the following embodiments are illustrative and not limiting, and should not be construed as limiting the scope of protection of the present invention. All raw materials used in the following embodiments and comparative examples are commercially available.

[0027] The fumed silica used in this invention was purchased from Shanghai Bide Pharmaceutical Technology Co., Ltd., catalog number BD01383133, with a purity of 99.9%. However, it is not limited thereto.

[0028] Example 1: Preparation of Ce(OH)₂Cl (Literature Method) 7.6 g NaCl (130 mmol), 3.7 g CeCl3·7H2O (10 mmol), and 1.4 g hexamethylenetetramine (10 mmol) were weighed and added sequentially to a 250 mL round-bottom flask containing 100 mL deionized water. The mixture was magnetically stirred at room temperature until the sample was completely dissolved. The flask containing the mixed solution was then placed in a 90 °C oil bath, and the magnetic stirring speed was set to 350 rpm. A condenser was inserted, and the mixture was heated under reflux for 12 hours. After the reaction was complete, the sample was allowed to cool naturally to room temperature. The mixed solution was filtered to obtain a solid powder. The sample was repeatedly filtered and washed with deionized water and ethanol, and then vacuum dried at 60 °C. The obtained sample was Ce(OH)2Cl. The specific surface area of ​​the sample was determined to be 21.2 m² / g by nitrogen physical adsorption-desorption experiment. 2 / g.

[0029] Example 2: 2.3 Preparation of Ce(OH)2Cl / SiO2 7.6 g NaCl (130 mmol), 3.7 g CeCl3·7H2O (10 mmol), and 1.4 g hexamethylenetetramine (10 mmol) were weighed and added sequentially to a 250 mL round-bottom flask containing 100 mL deionized water. The mixture was magnetically stirred at room temperature until the sample was completely dissolved. The flask containing the mixed solution was then placed in a 90 °C oil bath, and the magnetic stirring speed was set to 600 rpm. After inserting a condenser, the mixture was heated under reflux for 90 min. 0.5 g of fumed silica was added, and the mixture was heated under reflux for another 4.5 h. After the reaction was complete, the sample was allowed to cool naturally to room temperature. The mixed solution was filtered to obtain a solid powder. The sample was repeatedly filtered and washed with deionized water and ethanol, then vacuum dried at 60 °C, and finally calcined at 280 °C under an argon atmosphere for 3 h (heating rate 2 °C / min). The resulting sample was 2,3Ce(OH)2Cl / SiO2. X-ray fluorescence spectroscopy revealed a Ce / SiO2 mass ratio of 2.3 in the sample. Nitrogen physical adsorption-desorption experiments determined the sample's specific surface area to be 78.3 m². 2 / g.

[0030] Example 3: Preparation of 0.8Ce(OH)2Cl / SiO2 The preparation method of Example 2 was followed, except that the mass of fumed silica added was changed from 0.5 g to 1.0 g. X-ray fluorescence spectroscopy revealed that the Ce / SiO2 mass ratio in the sample was 0.8. Nitrogen physical adsorption-desorption experiments determined the specific surface area of ​​the sample to be 105.6 m². 2 / g.

[0031] Example 4: Preparation of 0.4Ce(OH)2Cl / SiO2 The preparation method of Example 2 was followed, except that the mass of fumed silica added was changed from 0.5 g to 1.5 g. X-ray fluorescence spectroscopy revealed that the Ce / SiO2 mass ratio in the sample was 0.4. Nitrogen physical adsorption-desorption experiments determined the specific surface area of ​​the sample to be 120.1 m². 2 / g.

[0032] Example 5: Preparation of 0.2Ce(OH)2Cl / SiO2 The preparation method of Example 2 was followed, except that the mass of fumed silica added was changed from 0.5 g to 2.0 g. X-ray fluorescence spectroscopy revealed that the Ce / SiO2 mass ratio in the sample was 0.2. Nitrogen physical adsorption-desorption experiments determined the specific surface area of ​​the sample to be 139.7 m². 2 / g.

[0033] Example 6: Performance evaluation of Ce(OH)₂Cl catalytic carbon dioxide cycloaddition reaction over 1 h (taking epoxide as an example) In a high-pressure reactor, 100 mg of the Ce(OH)₂Cl catalyst obtained in Example 1, 1 mL of epoxide, and 3 mL of DMF were added sequentially. CO₂ was introduced to bring the pressure to 1.5 MPa, and the temperature was raised to 150 °C for 1 h. After the reaction, the reactor was cooled to below 10 °C in an ice-water bath and the pressure was released. A sample was taken, and biphenyl was added as an internal standard. Quantitative analysis was performed by gas chromatography, and the yield of butenyl carbonate was 17%.

[0034] Example 7: 2.3 Performance evaluation of the catalytic carbon dioxide cycloaddition reaction of Ce(OH)₂Cl / SiO₂ for 1 h The other steps are the same as in Example 6, except that the catalyst used is changed from Ce(OH)₂Cl to the 2,3Ce(OH)₂Cl / SiO₂ obtained in Example 2. The yield of butene carbonate is 60%.

[0035] Example 8: Performance evaluation of the catalytic carbon dioxide cycloaddition reaction of 0.8Ce(OH)2Cl / SiO2 for 1 h The other steps are the same as in Example 6, except that the catalyst used is changed from Ce(OH)₂Cl to 0.8Ce(OH)₂Cl / SiO₂. The yield of butene carbonate is 66%.

[0036] Example 9: Performance evaluation of the catalytic carbon dioxide cycloaddition reaction of 0.4Ce(OH)2Cl / SiO2 for 1 h The other steps are the same as in Example 6, except that the catalyst used is changed from Ce(OH)₂Cl to 0.4Ce(OH)₂Cl / SiO₂. The yield of butene carbonate is 69%.

[0037] Example 10: Performance evaluation of the catalytic carbon dioxide cycloaddition reaction of 0.2Ce(OH)2Cl / SiO2 for 1 h The other steps are the same as in Example 6, except that the catalyst used is changed from Ce(OH)₂Cl to 0.2Ce(OH)₂Cl / SiO₂. The yield of butene carbonate is 62%.

[0038] Example 11: Performance evaluation of the catalytic carbon dioxide cycloaddition reaction of 0.4Ce(OH)2Cl / SiO2 for 4 h The other steps are the same as in Example 6, except that the catalyst used is changed from Ce(OH)₂Cl to 0.4Ce(OH)₂Cl / SiO₂, and the reaction time is changed from 1 h to 4 h. The yield of butene carbonate is 94%.

[0039] Example 12: Performance evaluation of Ce(OH)₂Cl catalytic carbon dioxide cycloaddition reaction after 4 h The other steps are the same as in Example 6, except that the reaction time is changed from 1 h to 4 h. The yield of butenyl carbonate is 53%.

[0040] Example 13: Performance evaluation of solvent-free reaction of 0.4Ce(OH)₂Cl / SiO₂ for catalytic carbon dioxide cycloaddition 4 h The other steps are the same as in Example 6, except that DMF is not added, the catalyst is changed from Ce(OH)₂Cl to 0.4Ce(OH)₂Cl / SiO₂, and the reaction time is changed from 1 h to 4 h. The yield of butene carbonate is 45%.

[0041] Example 14: Performance evaluation of the catalytic reaction of 0.4Ce(OH)2Cl / SiO2 with propylene oxide for 4 h The other steps are the same as in Example 6, except that the catalyst used is changed from Ce(OH)₂Cl to 0.4Ce(OH)₂Cl / SiO₂, the epoxide is changed from butane to propylene oxide, and the reaction time is changed from 1 h to 4 h. The yield of propylene carbonate is 96%.

[0042] Example 15: Performance evaluation of the catalytic epichlorohydrin reaction of 0.4Ce(OH)2Cl / SiO2 for 4 h The other steps are the same as in Example 6, except that the catalyst used is changed from Ce(OH)₂Cl to 0.4Ce(OH)₂Cl / SiO₂, the butylene oxide is changed to epichlorohydrin, and the reaction time is changed from 1 h to 4 h. The yield of propylene carbonate is 96%.

[0043] Example 16: Performance evaluation of the catalytic oxidation of styrene with 0.4Ce(OH)2Cl / SiO2 for 4 h The other steps are the same as in Example 6, except that the catalyst is changed from Ce(OH)₂Cl to 0.4Ce(OH)₂Cl / SiO₂, the epoxide is changed to styrene oxide, and the reaction time is changed from 1 h to 4 h. The yield of styrene carbonate is 95%.

[0044] Example 17: Performance evaluation of the catalytic reaction of allyl glycidyl ether with 0.4Ce(OH)2Cl / SiO2 for 4 h The other steps are the same as in Example 6, except that the catalyst used is changed from Ce(OH)₂Cl to 0.4Ce(OH)₂Cl / SiO₂, the epoxide is changed to allyl glycidyl ether, and the reaction time is changed from 1 h to 4 h. The yield of the corresponding cyclic carbonate (4-((allyloxy)methyl)-1,3-dioxocyclopentan-2-one) is 95%.

[0045] Comparative Example 1: Catalyst-free carbon dioxide cycloaddition experiment The other steps were the same as in Example 6, but without the addition of any catalyst. The yield of butenyl carbonate was 2.0%. This result indicates that DMF has only a small amount of catalytic activity for the carbon dioxide cycloaddition reaction, but its activity is enhanced by enriching CO2 when coexisting with the 0.4Ce(OH)2Cl / SiO2 catalyst.

[0046] Comparative Example 2: Catalyst-free and solvent-free carbon dioxide cycloaddition experiment The other steps were the same as in Example 6, but without the addition of any catalyst or solvent, and under the same conditions. The yield of butene carbonate was 0.

[0047] Comparative Example 3: Performance evaluation of the physical mixed catalysis of Ce(OH)₂Cl and SiO₂ for the carbon dioxide cycloaddition reaction (1 h) The other steps are the same as in Example 6, except that the catalyst used is changed from 100 mg Ce(OH)₂Cl to 37.4 mg Ce(OH)₂Cl and 62.6 mg SiO₂. (The Ce / SiO₂ mass ratio is the same as 0.4 Ce(OH)₂Cl / SiO₂.) The yield of butene carbonate is 9%.

[0048] Comparative Example 4: Performance evaluation of carbon dioxide cycloaddition reaction catalyzed by fumed silica over 1 h The other steps are the same as in Example 6, except that the catalyst used was changed from 100 mg Ce(OH)₂Cl to fumed silica. The yield of butenyl carbonate was 0%. These results indicate that the pure SiO₂ support has almost no catalytic activity for the CO₂ cycloaddition reaction; the catalytic activity originates from the supported Ce(OH)₂Cl species.

[0049] The present invention has been described above by way of example. It should be noted that any simple modifications, alterations or other equivalent substitutions that can be made by those skilled in the art without creative effort without departing from the core of the present invention fall within the protection scope of the present invention.

[0050] Matters not covered in this invention are common knowledge.

Claims

1. A method for preparing a supported cerium hydroxychloride catalyst, characterized in that, Includes the following steps: (1) Dissolve chloride salt, alkali and cerium salt in deionized water and reflux at 45-95℃ for 30-120 min with stirring; The molar ratio of chloride salt, alkali, and cerium salt is (10-30):(1-5):1; (2) Add the silicon-based support to the reaction solution of step (1) and continue to stir and reflux at 45-95℃ for 3-12 h; Each 10 mmol of cerium salt corresponds to 0.5-6.0 g of silicon-based support; (3) Filter the reaction mixture obtained in step (2), collect the solid powder, wash it with water and ethanol, and then dry it under vacuum; (4) The dried product obtained in step (3) is heated to 200-300℃ and calcined for 1-5 h under an inert atmosphere to obtain a supported cerium hydroxychloride catalyst.

2. The method for preparing the supported cerium hydroxychloride catalyst as described in claim 1, characterized in that, The chloride salt mentioned in step (1) is sodium chloride or potassium chloride; The alkali is hexamethylenetetramine, ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate, ammonium bicarbonate, sodium bicarbonate, potassium carbonate, or potassium bicarbonate. The cerium salt is one of hydrated cerium chloride, hydrated cerium nitrate, or hydrated cerium sulfate.

3. The method for preparing the supported cerium hydroxychloride catalyst as described in claim 1, characterized in that, In step (1), 5-20 mmol of cerium salt is added to every 100 mL of deionized water.

4. The method for preparing the supported cerium hydroxychloride catalyst as described in claim 1, characterized in that, The silicon-based support mentioned in step (2) is one of fumed silica, molecular sieve or porous silica gel.

5. The method for preparing the supported cerium hydroxychloride catalyst as described in claim 1, characterized in that, In step (1), the stirring speed is 300-600 rpm; in step (3), the vacuum drying temperature is 60-80℃ and the time is 12-24 h; in step (4), the inert atmosphere is argon, nitrogen or helium; in step (4), the heating rate is 2-10 ℃ / min.

6. The method for preparing the supported cerium hydroxychloride catalyst as described in claim 1, characterized in that, The catalyst has a specific surface area of ​​70-300 m². 2 / g.

7. The application of the supported cerium hydroxychloride catalyst prepared by the method described in claim 1, characterized in that, Used to catalyze the cycloaddition reaction of CO2 to prepare cyclic carbonates.

8. The application as described in claim 7, characterized in that, The epoxide and the supported cerium hydroxychloride catalyst were added to a high-pressure reactor, CO2 was introduced, and the reaction was carried out at 0.5-3 MPa and 80-160℃ for 1-6 h. After the reaction was completed, the reactor was cooled to below 10℃ and the pressure was released to obtain cyclic carbonate. Each milliliter of epoxide contains 50-150 mg of supported cerium hydroxychloride catalyst; The epoxide is ethylene oxide, propylene oxide, butane oxide, epichlorohydrin, styrene oxide, or allyl glycidyl ether.

9. The application as described in claim 7, characterized in that, The reaction is carried out in the presence of a polar aprotic solvent with a volume ratio of solvent to epoxide of (1-10):

1. The polar aprotic solvent is N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, or N-methylpyrrolidone.

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