Method for synthesizing electronic-grade ethyl acetate through catalytic esterification of acidic ion exchange resin

Abstract

The invention discloses a method for synthesizing electronic-grade ethyl acetate through catalytic esterification of acidic ion exchange resin, and belongs to the technical field of ethyl acetate preparation. The method comprises the following steps: mixing crosslinked polystyrene white balls and a swelling agent, and dropwise adding concentrated sulfuric acid for reaction to obtain S-PS resin; mixing an EDTA disodium salt saturated solution and a polyacrylic acid solution, adding a cross-linking agent and an emulsifier, and carrying out a cross-linking curing reaction to obtain EDTA microcapsules; the preparation method comprises the following steps: dispersing S-PS resin in a solvent, adding EDTA microcapsules, a dehydration condensation agent and a catalyst, reacting under the protection of inert gas, and filtering and recovering after the reaction is finished to obtain S-PS-EDTA resin; mixing glacial acetic acid, absolute ethyl alcohol and S-PS (at) EDTA resin for reaction, and filtering and collecting liquid after the reaction is finished; and rectifying the collected liquid to obtain the product. According to the method provided by the invention, metal impurities can be chelated in the synthesis process, and the electronic-grade ethyl acetate with high purity and low impurity content is produced.

Description

Technical Field

[0001] This invention belongs to the field of ethyl acetate preparation technology, specifically relating to a method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin. Background Technology

[0002] Electronic-grade ethyl acetate is a crucial high-end solvent widely used in photolithography, cleaning, and etching processes in semiconductor chip manufacturing. Its purity requirements are extremely high, especially regarding the strict limits on trace metal impurities (such as Fe, Na, K, and Ca). There are various methods for synthesizing ethyl acetate, the most common being the direct esterification of acetic acid and ethanol under acid catalysis. Acidic ion exchange resins, as solid acid catalysts, can significantly accelerate the esterification reaction rate, thereby improving reaction efficiency and product quality.

[0003] Although acidic resin catalysis technology is mature, some shortcomings still exist in producing qualified electronic-grade ultra-high purity products. Traditional acidic resins only possess catalytic function and lack purification capabilities. Trace metal ions in the reaction system may originate from the dissolution of raw materials, equipment, or reactor materials. These metal impurities can act as Lewis acids, initiating side reactions and leading to substandard product purity. Furthermore, metal impurities in the raw materials not only contaminate the product but also poison the acidic sites of the catalyst or deposit within the resin pores, resulting in decreased catalyst activity and shortened lifespan. Therefore, it is essential to develop a novel method for the esterification synthesis of electronic-grade ethyl acetate using acidic ion exchange resin catalysis. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method for synthesizing electronic grade ethyl acetate by catalysis of acidic ion exchange resin.

[0005] The present invention provides a method for synthesizing electronic-grade ethyl acetate by catalytic esterification using acidic ion exchange resin, comprising the following steps: S1: Cross-linked polystyrene white spheres and swelling agent are mixed, concentrated sulfuric acid is added dropwise to carry out sulfonation reaction, after the reaction is completed, the mixture is cooled to room temperature, washed until neutral, and then dried to obtain S-PS resin; S2: Mix a saturated solution of disodium EDTA salt and a polyacrylic acid solution, add a crosslinking agent and an emulsifier to carry out a crosslinking and curing reaction, and after the reaction is completed, separate the microcapsules, wash and dry them to obtain EDTA microcapsules; S3: S-PS resin is dispersed in a solvent, EDTA microcapsules, dehydrating condensing agent and catalyst one are added, and the reaction takes place under inert gas protection. After the reaction is completed, the resin is recovered by filtration. The resin is washed and dried to obtain S-PS@EDTA resin. S4: Using S-PS@EDTA resin as catalyst 2, glacial acetic acid and anhydrous ethanol are subjected to esterification reaction. After the reaction is completed, the liquid is collected by cooling and filtration. S5: The liquid collected in step S4 is subjected to distillation to separate electronic grade ethyl acetate.

[0006] It should be noted that this invention involves swelling cross-linked polystyrene (PS) spheres to allow organic solvent molecules to penetrate the resin interior, expanding its polymer network. Then, sulfonic acid groups are introduced at the para-position of the benzene ring to generate sulfonated cross-linked polystyrene resin (S-PS resin). EDTA microcapsules, under the action of catalyst one and a dehydrating condensing agent, are covalently modified onto the surface of the sulfonated polystyrene resin (S-PS), resulting in a firm bond between the EDTA microcapsules and the PS resin surface, forming S-PS@EDTA resin.

[0007] In some embodiments, the swelling agent is selected from at least one of dichloromethane and tetrahydrofuran; the amount of swelling agent used is 1.5-2.5 times the mass of the cross-linked polystyrene white balls; and the mass ratio of concentrated sulfuric acid to swelling agent is 1:2-3.

[0008] In some embodiments, the polyacrylic acid solution is prepared by mixing polyacrylic acid and deionized water at a mass ratio of 0.5-1:5; the mass ratio of saturated EDTA disodium salt solution, polyacrylic acid solution, crosslinking agent and emulsifier is 6-7:5.5-6.5:0.1-0.3:0.05-0.25.

[0009] In some embodiments, the crosslinking agent is selected from at least one of N,N'-methylenebisacrylamide and glutaraldehyde; the emulsifier is selected from at least one of Tween-80 and poloxamer.

[0010] In some embodiments, the solvent is selected from at least one of DMF and DMSO; the dehydrating condensing agent is selected from at least one of N,N-dicyclohexylcarbodiimide and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride; and the catalyst is selected from at least one of 4-dimethylaminopyridine and p-toluenesulfonic acid.

[0011] In some embodiments, the amount of EDTA microcapsules is 25-35% of the mass of S-PS resin; the mass ratio of EDTA microcapsules, dehydrating condensing agent and catalyst is 14-16:7-9:1.

[0012] In some embodiments, the mass ratio of glacial acetic acid, anhydrous ethanol, and S-PS@EDTA resin is 46-50:42-45:4-7.

[0013] In some embodiments, in S1, the mixing time is 1.5-2.5 h, the sulfonation reaction temperature is 40-50 °C, the sulfonation reaction time is 6-8 h, and the drying is carried out at 95-105 °C to constant weight.

[0014] In some embodiments, in S2, the crosslinking curing reaction is carried out by stirring in a water bath at 60-70°C for 2-3 hours; in S3, the reaction temperature is 75-85°C, the reaction time is 20-22 hours, and the drying temperature is 55-65°C.

[0015] In some embodiments, in S4, the esterification reaction temperature is 110-120°C and the esterification reaction time is 4-6 hours; in S5, the fraction at 76-78°C is collected by distillation.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention creatively constructs a protective layer with ethylenediaminetetraacetic acid (EDTA) as the key substance on the surface of sulfonated crosslinked polystyrene resin. Since sulfonated crosslinked polystyrene resin itself has catalytic function for esterification reactions, this allows the S-PS@EDTA resin to simultaneously possess the functions of catalyzing esterification and chelating and removing metal ions. The protective layer slowly hydrolyzes under the acidic hydrothermal environment of the esterification reaction, releasing highly efficient chelating agent EDTA molecules on demand and continuously. EDTA molecules can capture metal impurities as they dissolve from equipment or raw materials, forming stable complexes that reduce impurities in the product, directly producing electronic-grade ethyl acetate with low metal impurity content and high purity. Furthermore, by capturing metal ions, the protective layer also provides effective protection for the sulfonate resin, reducing deactivation caused by metal poisoning and thus extending the catalyst's lifespan.

[0017] This invention encapsulates EDTA in microcapsules, the shell of which is composed of a pH-responsive polymer, polyacrylic acid, which allows it to slowly dissolve in the acidic environment of the esterification reaction. As the pH decreases during the esterification reaction (acidic environment), it slowly dissolves and releases EDTA, achieving purification in sync with the reaction progress. This avoids efficiency loss due to premature release and also makes the release of EDTA more uniform, thereby improving the metal chelation efficiency of EDTA.

[0018] The electronic-grade ethyl acetate preparation method provided by this invention achieves in-situ and targeted removal of metal impurities during the preparation process, simplifying the subsequent purification process and eliminating the need for complex purification steps such as multi-stage distillation, adsorption columns, or ion exchange resins. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to specific embodiments.

[0020] Example 1 A method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin includes the following steps: S1: Cross-linked polystyrene white spheres and dichloromethane were mixed for 2 hours, and concentrated sulfuric acid was added dropwise to sulfonate the mixture at 45°C for 7 hours. After the reaction was completed, the mixture was cooled to room temperature, washed until neutral, and dried at 100°C to constant weight to obtain S-PS resin. The amount of dichloromethane used was 1.5-2.5 times the mass of the cross-linked polystyrene white spheres, and the mass ratio of concentrated sulfuric acid to dichloromethane was 1:2-3. S2: A saturated solution of disodium EDTA and a polyacrylic acid solution were mixed, and N,N'-methylenebisacrylamide and Tween-80 were added. The mixture was stirred in a water bath at 65°C for 2 hours. After the reaction was completed, the microcapsules were separated, washed, and dried to obtain EDTA microcapsules. The polyacrylic acid solution was prepared by mixing polyacrylic acid and deionized water at a mass ratio of 0.8:5. The mass ratio of the saturated solution of disodium EDTA, the polyacrylic acid solution, N,N'-methylenebisacrylamide, and Tween-80 was 6.5:6:0.2:0.2. S3: S-PS resin was dispersed in DMF, and EDTA microcapsules, N,N-dicyclohexylcarbodiimide, and 4-dimethylaminopyridine were added in a mass ratio of 15:8:1. The mixture was reacted at 80°C for 21 h under inert gas protection. After the reaction was completed, the resin was recovered by filtration. The resin was washed and dried at 60°C to obtain S-PS@EDTA resin. The amount of EDTA microcapsules used was 30% of the mass of S-PS resin. S4: Glacial acetic acid, anhydrous ethanol and S-PS@EDTA resin in a mass ratio of 48:43:6 were mixed and esterified at 115℃ for 5 hours. After the reaction was completed, the mixture was cooled, filtered and the liquid was collected. S5: Distill the liquid collected in step S4 and collect the fraction at 76-78℃ to obtain electronic grade ethyl acetate.

[0021] Example 2 A method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin includes the following steps: S1: Cross-linked polystyrene white spheres and tetrahydrofuran were mixed for 2.5 h, concentrated sulfuric acid was added dropwise and sulfonated at 50 °C for 6 h. After the reaction was completed, the mixture was cooled to room temperature, washed until neutral, and dried at 105 °C to constant weight to obtain S-PS resin. The amount of tetrahydrofuran was 2.5 times the mass of the cross-linked polystyrene white spheres, and the mass ratio of concentrated sulfuric acid to tetrahydrofuran was 1:3. S2: A saturated solution of disodium EDTA and a polyacrylic acid solution were mixed, and glutaraldehyde and poloxamer were added. The mixture was stirred in a water bath at 70°C for 2 hours. After the reaction was completed, the microcapsules were separated, washed, and dried to obtain EDTA microcapsules. The polyacrylic acid solution was prepared by mixing polyacrylic acid and deionized water at a mass ratio of 1:5. The mass ratio of the saturated solution of disodium EDTA, the polyacrylic acid solution, glutaraldehyde, and poloxamer was 7:6.5:0.3:0.25. S3: S-PS resin was dispersed in DMSO, and EDTA microcapsules, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and p-toluenesulfonic acid were added in a mass ratio of 16:9:1. The reaction was carried out under inert gas protection at 85°C for 22 h. After the reaction was completed, the resin was recovered by filtration. The resin was washed and dried at 65°C to obtain S-PS@EDTA resin. The amount of EDTA microcapsules used was 35% of the mass of S-PS resin. S4: Glacial acetic acid, anhydrous ethanol and S-PS@EDTA resin in a mass ratio of 50:45:7 were mixed and esterified at 120°C for 6 hours. After the reaction was completed, the mixture was cooled, filtered and the liquid was collected. S5: Distill the liquid collected in step S4 and collect the fraction at 76-78℃ to obtain electronic grade ethyl acetate.

[0022] Example 3 A method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin includes the following steps: S1: Cross-linked polystyrene white spheres and dichloromethane were mixed for 1.5 h, concentrated sulfuric acid was added dropwise, and sulfonation reaction was carried out at 40 °C for 8 h. After the reaction was completed, the mixture was cooled to room temperature, washed until neutral, and dried at 95 °C to constant weight to obtain S-PS resin. The amount of dichloromethane used was 1.5 times the mass of cross-linked polystyrene white spheres, and the mass ratio of concentrated sulfuric acid to dichloromethane was 1:2. S2: A saturated solution of disodium EDTA and a polyacrylic acid solution were mixed, and N,N'-methylenebisacrylamide and poloxamer were added. The mixture was stirred in a water bath at 60°C for 3 hours. After the reaction was completed, the microcapsules were separated, washed, and dried to obtain EDTA microcapsules. The polyacrylic acid solution was prepared by mixing polyacrylic acid and deionized water in a mass ratio of 0.5:5. The mass ratio of the saturated solution of disodium EDTA, the polyacrylic acid solution, N,N'-methylenebisacrylamide, and poloxamer was 6:5.5:0.1:0.05. S3: S-PS resin was dispersed in DMF, and EDTA microcapsules, N,N-dicyclohexylcarbodiimide, and 4-dimethylaminopyridine were added in a mass ratio of 14:7:1. The mixture was reacted at 75°C for 20 hours under inert gas protection. After the reaction was completed, the resin was recovered by filtration. The resin was washed and dried at 55°C to obtain S-PS@EDTA resin. The amount of EDTA microcapsules used was 25% of the mass of S-PS resin. S4: Glacial acetic acid, anhydrous ethanol and S-PS@EDTA resin in a mass ratio of 46:42:4 were mixed and esterified at 110℃ for 4 hours. After the reaction was completed, the mixture was cooled, filtered and the liquid was collected. S5: Distill the liquid collected in step S4 and collect the fraction at 76-78℃ to obtain electronic grade ethyl acetate.

[0023] Example 4 A method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin includes the following steps: S1: Cross-linked polystyrene white spheres and tetrahydrofuran were mixed for 2.5 h, concentrated sulfuric acid was added dropwise, and sulfonation reaction was carried out at 50 °C for 8 h. After the reaction was completed, the mixture was cooled to room temperature, washed until neutral, and dried at 95 °C to constant weight to obtain S-PS resin. The amount of tetrahydrofuran was twice the mass of the cross-linked polystyrene white spheres, and the mass ratio of concentrated sulfuric acid to tetrahydrofuran was 1:2.5. S2: A saturated solution of disodium EDTA and a polyacrylic acid solution were mixed, and glutaraldehyde and Tween-80 were added. The mixture was stirred in a water bath at 65°C for 3 hours. After the reaction was completed, the microcapsules were separated, washed, and dried to obtain EDTA microcapsules. The polyacrylic acid solution was prepared by mixing polyacrylic acid and deionized water at a mass ratio of 1:5. The mass ratio of the saturated solution of disodium EDTA, the polyacrylic acid solution, glutaraldehyde, and Tween-80 was 6:5.5:0.3:0.05. S3: S-PS resin was dispersed in DMF, and EDTA microcapsules, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and 4-dimethylaminopyridine were added in a mass ratio of 15:9:1. The mixture was reacted at 78°C for 21 h under inert gas protection. After the reaction was completed, the resin was recovered by filtration. The resin was washed and dried at 60°C to obtain S-PS@EDTA resin. The amount of EDTA microcapsules used was 28% of the mass of S-PS resin. S4: Glacial acetic acid, anhydrous ethanol and S-PS@EDTA resin in a mass ratio of 47:44:6 were mixed and esterified at 115°C for 4 hours. After the reaction was completed, the mixture was cooled, filtered and the liquid was collected. S5: Distill the liquid collected in step S4 and collect the fraction at 76-78℃ to obtain electronic grade ethyl acetate.

[0024] Example 5 A method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin includes the following steps: S1: Cross-linked polystyrene white spheres and tetrahydrofuran were mixed for 2.5 h, concentrated sulfuric acid was added dropwise, and sulfonation reaction was carried out at 48 °C for 8 h. After the reaction was completed, the mixture was cooled to room temperature, washed until neutral, and dried at 105 °C to constant weight to obtain S-PS resin. The amount of tetrahydrofuran was 2.3 times the mass of the cross-linked polystyrene white spheres, and the mass ratio of concentrated sulfuric acid to tetrahydrofuran was 1:2.5. S2: A saturated solution of disodium EDTA and a polyacrylic acid solution were mixed, and N,N'-methylenebisacrylamide and Tween-80 were added. The mixture was stirred in a water bath at 70°C for 3 hours. After the reaction was completed, the microcapsules were separated, washed, and dried to obtain EDTA microcapsules. The polyacrylic acid solution was prepared by mixing polyacrylic acid and deionized water at a mass ratio of 1:5. The mass ratio of the saturated solution of disodium EDTA, the polyacrylic acid solution, N,N'-methylenebisacrylamide, and Tween-80 was 7:5.5:0.3:0.15. S3: S-PS resin was dispersed in DMSO, and EDTA microcapsules, N,N-dicyclohexylcarbodiimide, and p-toluenesulfonic acid were added in a mass ratio of 16:8:1. The reaction was carried out under inert gas protection at 83°C for 21.5 h. After the reaction was completed, the resin was filtered and recovered. The resin was washed and dried at 62°C to obtain S-PS@EDTA resin. The amount of EDTA microcapsules used was 32% of the mass of S-PS resin. S4: Glacial acetic acid, anhydrous ethanol and S-PS@EDTA resin in a mass ratio of 49:43:5 were mixed and esterified at 115℃ for 5.5h. After the reaction was completed, the mixture was cooled, filtered and the liquid was collected. S5: Distill the liquid collected in step S4 and collect the fraction at 76-78℃ to obtain electronic grade ethyl acetate.

[0025] Comparative Example 1 It is basically the same as Example 1, except that the S-PS@EDTA resin in S4 is replaced with the same amount of S-PS resin, that is, steps S2 and S3 are omitted.

[0026] Comparative Example 2 This is essentially the same as Example 1, except that the S-PS@EDTA resin in S4 is replaced with the same amount of conventional acidic ion exchange resin (catalyst source: Amberlyst). TM- 15. DuPont, Inc. (USA) Comparative Example 3 It is basically the same as Example 1, except that S-PS@EDTA resin is not added in S4, that is, steps S1, S2 and S3 are omitted.

[0027] Comparative Example 4 It is basically the same as Example 1, except that the EDTA microcapsules in S3 are replaced with the same amount of EDTA disodium salt, that is, step S2 is omitted.

[0028] The performance of ethyl acetate prepared in Examples 1-5 and Comparative Examples 1-4 was determined. Inductively coupled plasma mass spectrometry (ICP-MS) was used to test the content of metal impurities. Ten mL of each component ethyl acetate was filtered through a 0.22 μm PTFE membrane, slightly acidified with 2% ultrapure nitric acid, and then injected for analysis. Gas chromatography (GC) was used to test the purity of ethyl acetate using a DB-624 column and programmed temperature rise. The Karl Fischer coulometric method was used to determine the water content of ethyl acetate. The test results are shown in Table 1.

[0029] Table 1 As shown in Table 1, the ethyl acetate provided in Examples 1-5 of this invention meets electronic grade standards in terms of purity, moisture content, and total metal content, indicating that the S-PS@EDTA resin can efficiently chelate and remove trace metal ions, achieving targeted purification. Comparing with the comparative examples, it can be seen that Comparative Example 1, due to the use of S-PS resin without an EDTA layer, has a significantly higher content of metal impurities in the product, indicating that sulfonic acid resin does not have the ability to purify metal impurities; Comparative Example 2 uses a commercial resin catalyst, and its total metal content is also high, indicating that a single-function catalyst cannot purify impurities; Comparative Example 3 lacks a catalyst, resulting in incomplete reaction and extremely high impurity content in the product; Comparative Example 4 did not use EDTA microcapsules, resulting in the inability to release EDTA as needed, leading to a decrease in purification efficiency and product quality.

[0030] The above descriptions are merely some embodiments of the present invention. Those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin, characterized in that, Includes the following steps: S1: Cross-linked polystyrene white spheres and swelling agent are mixed, concentrated sulfuric acid is added dropwise to carry out sulfonation reaction, after the reaction is completed, the mixture is cooled to room temperature, washed until neutral, and then dried to obtain S-PS resin; S2: Mix a saturated solution of disodium EDTA salt and a polyacrylic acid solution, add a crosslinking agent and an emulsifier to carry out a crosslinking and curing reaction, and after the reaction is completed, separate the microcapsules, wash and dry them to obtain EDTA microcapsules; S3: The S-PS resin is dispersed in a solvent, and the EDTA microcapsules, dehydrating condensing agent and catalyst one are added. The reaction takes place under inert gas protection. After the reaction is completed, the resin is recovered by filtration. The resin is washed and dried to obtain S-PS@EDTA resin. S4: Using the S-PS@EDTA resin as catalyst two, acetic acid and anhydrous ethanol are subjected to esterification reaction. After the reaction is completed, the mixture is cooled, filtered, and the liquid is collected. S5: The liquid collected in step S4 is subjected to distillation to separate electronic grade ethyl acetate.

2. The method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin according to claim 1, characterized in that, The swelling agent is selected from at least one of dichloromethane and tetrahydrofuran; the amount of the swelling agent is 1.5-2.5 times the mass of the cross-linked polystyrene white balls; the mass ratio of the concentrated sulfuric acid to the swelling agent is 1:2-3.

3. The method for synthesizing electronic-grade ethyl acetate by catalytic esterification using acidic ion exchange resin according to claim 1, characterized in that, The polyacrylic acid solution is prepared by mixing polyacrylic acid and deionized water at a mass ratio of 0.5-1:5; the mass ratio of the saturated EDTA disodium salt solution, the polyacrylic acid solution, the crosslinking agent, and the emulsifier is 6-7:5.5-6.5:0.1-0.3:0.05-0.

25.

4. The method for synthesizing electronic-grade ethyl acetate by catalytic esterification using acidic ion exchange resin according to claim 3, characterized in that, The crosslinking agent is selected from at least one of N,N'-methylenebisacrylamide and glutaraldehyde; the emulsifier is selected from at least one of Tween-80 and poloxamer.

5. The method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin according to claim 1, characterized in that, The solvent is selected from at least one of DMF and DMSO; the dehydrating condensing agent is selected from at least one of N,N-dicyclohexylcarbodiimide and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride; and the catalyst is selected from at least one of 4-dimethylaminopyridine and p-toluenesulfonic acid.

6. The method for synthesizing electronic-grade ethyl acetate by catalytic esterification using acidic ion exchange resin according to claim 5, characterized in that, The amount of EDTA microcapsules used is 25-35% of the mass of the S-PS resin; the mass ratio of the EDTA microcapsules, dehydrating condensing agent and catalyst is 14-16:7-9:

1.

7. The method for synthesizing electronic-grade ethyl acetate by catalytic esterification using acidic ion exchange resin according to claim 1, characterized in that, The mass ratio of glacial acetic acid, anhydrous ethanol, and S-PS@EDTA resin is 46-50:42-45:4-7.

8. The method for synthesizing electronic-grade ethyl acetate by catalytic esterification using acidic ion exchange resin according to claim 1, characterized in that, In S1, the mixing time is 1.5-2.5h, the sulfonation reaction temperature is 40-50℃, the sulfonation reaction time is 6-8h, and the drying is carried out at 95-105℃ to constant weight.

9. The method for synthesizing electronic-grade ethyl acetate by esterification catalyzed by acidic ion exchange resin according to claim 1, characterized in that, In step S2, the crosslinking and curing reaction is carried out by stirring in a water bath at 60-70°C for 2-3 hours; in step S3, the reaction temperature is 75-85°C, the reaction time is 20-22 hours, and the drying temperature is 55-65°C.

10. The method for synthesizing electronic-grade ethyl acetate by catalytic esterification using acidic ion exchange resin according to claim 1, characterized in that, In step S4, the esterification reaction temperature is 110-120℃ and the esterification reaction time is 4-6h; in step S5, the fraction at 76-78℃ is collected by distillation.

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