Method for refining acetone and electronic grade acetone product thereof

Abstract

The present application relates to the technical field of electronic grade reagent, and particularly relates to a refining method of acetone and an electronic grade acetone product thereof. The purity of the acetone product is not less than 99.99%, the water content in the acetone product is not higher than 100 ppm, the content of aldehyde compounds is not higher than 3 ppm, and the evaporation residue content is not higher than 1 ppm. The refining method of acetone comprises the following steps: the crude acetone is contacted with a mixed solution containing an oxidizing agent and a strong base, and then the electronic grade acetone product is obtained through rectification, dehydration, deionization and microparticle removal. The refining method of acetone in the present application can obtain the electronic grade acetone product suitable for higher requirement semiconductor application scenarios. The electronic grade acetone product in the present application has good quality and high purity, and the content of aldehyde compounds and the evaporation residue content in the acetone product are both very low, so that the electronic grade acetone product can be suitable for higher requirement semiconductor application scenarios.

Description

Technical Field

[0001] This invention relates to the field of electronic-grade reagent technology, specifically to a method for purifying acetone and its electronic-grade acetone product. Background Technology

[0002] Acetone, also known as dimethyl ketone, is the simplest ketone in the saturated fatty ketone series. It has a melting point of -95°C and a boiling point of 56°C at normal pressure. It is highly volatile, easily ignited, and soluble in water, ethanol, and ether. Chemically active, it can undergo halogenation, addition, and condensation reactions, and can be used as a solvent for synthetic fibers, explosives, oils, and acetylene.

[0003] In the semiconductor field, acetone also plays an important role, serving as a cleaner and drier in processes such as large-scale integrated circuit manufacturing. Electronic-grade acetone has extremely stringent requirements regarding purity, water content, and the presence of residual metal cations, anions, and particulates. Therefore, the purification and refining processes for acetone place high demands on them.

[0004] Existing patent literature is limited, and the purification methods and effects described are generally limited. For example, CN201317750Y, CN104030903A, and CN114344932A do not consider the removal of aldehyde impurities from acetone raw materials, which will affect the purity of acetone. Therefore, developing a high-purity electronic-grade acetone suitable for more demanding semiconductor applications is an important technical problem that needs to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide a method for refining acetone and an electronic-grade acetone product thereof, which is suitable for more demanding semiconductor applications.

[0006] The first aspect of the present invention provides an electronic grade acetone product, wherein the acetone product has a purity of not less than 99.99%, and wherein the acetone product contains: water content not more than 100 ppm, aldehyde compound content not more than 3 ppm, and evaporation residue content not more than 1 ppm.

[0007] The second aspect of the present invention provides a method for refining acetone, the method comprising: contacting crude acetone with a mixed solution containing an oxidant and a strong alkali, followed by distillation, dehydration, deionization, and demicronization to obtain electronic-grade acetone; wherein the purity of the electronic-grade acetone is not less than 99.99%, and the acetone contains: a water content not exceeding 100 ppm, an aldehyde compound content not exceeding 3 ppm, and an evaporation residue content not exceeding 1 ppm.

[0008] Compared with the prior art, the present invention has at least the following advantages:

[0009] 1. The electronic-grade acetone product of this invention has good quality and high purity, and the content of aldehyde compounds and evaporation residue in the acetone product is very low, which can be used in semiconductor application scenarios with higher requirements.

[0010] 2. The acetone purification method of the present invention can obtain electronic-grade acetone products suitable for semiconductor application scenarios with higher requirements. Attached Figure Description

[0011] Figure 1 This is a schematic flowchart of a method for purifying acetone in one embodiment of the present invention.

[0012] Explanation of reference numerals in the attached figures

[0013] 1. Crude acetone 2. Mixed solution 3. Reaction materials

[0014] 4. Bottom layer products; 5. Coarse filtration products; 6. Top layer products.

[0015] 7. Concentrate 8. Deionized liquid 9. Acetone product

[0016] ① Stirred vessel ② Distillation column for removing light pollutants ③ Centrifugal filtration equipment

[0017] ④ Distillation deweight removal column ⑤ Pervaporation membrane equipment ⑥ Deionization column

[0018] ⑦ Filtration equipment Detailed Implementation

[0019] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0020] The first aspect of the present invention provides an electronic grade acetone product, wherein the acetone product has a purity of not less than 99.99%, and wherein the acetone product contains: water content not more than 100 ppm, aldehyde compound content not more than 3 ppm, and evaporation residue content not more than 1 ppm.

[0021] The electronic-grade acetone product of this invention has good quality and high purity, and the content of aldehyde compounds and evaporation residue in the acetone product is very low, making it suitable for semiconductor application scenarios with higher requirements.

[0022] According to the present invention, the acetone product provided by the present invention generally has a purity of 99.99-99.997%, preferably 99.993-99.997%, more preferably 99.994-99.997%, and even more preferably 99.996-99.997%. The purity in the present invention refers to the weight percentage.

[0023] According to some embodiments of the present invention, the aldehyde compounds include C1-C6 aldehydes, such as formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, pentanal, etc.

[0024] According to some preferred embodiments of the present invention, the acetone product contains 55-100 ppm of water, preferably 55-75 ppm, more preferably 55-66 ppm, and even more preferably 55-58 ppm.

[0025] According to some preferred embodiments of the present invention, the acetone product contains 0.1-3 ppm of aldehyde compounds, preferably 0.1-0.9 ppm, more preferably 0.1-0.5 ppm, and even more preferably 0.1-0.2 ppm.

[0026] According to some preferred embodiments of the present invention, the acetone product contains 0.4-1 ppm of evaporation residue, preferably 0.4-0.8 ppm, more preferably 0.4-0.6 ppm, and even more preferably 0.4-0.5 ppm.

[0027] According to some preferred embodiments of the present invention, the content of a single metal ion in the acetone product is not higher than 100 ppt, for example, not higher than 80 ppt, not higher than 60 ppt, not higher than 52 ppt, not higher than 50 ppt, not higher than 30 ppt, not higher than 28 ppt, etc.

[0028] According to some preferred embodiments of the present invention, the content of particles with an average particle size greater than 0.1 μm in the acetone product is not higher than 100 particles / ml, for example, 50 particles / ml, 53 particles / ml, 55 particles / ml, 56 particles / ml, 89 particles / ml, 97 particles / ml, preferably 50-56 particles / ml, more preferably 50-55 particles / ml, and even more preferably 50-53 particles / ml.

[0029] The second aspect of the present invention provides a method for refining acetone, the method comprising: contacting crude acetone with a mixed solution containing an oxidant and a strong alkali, followed by distillation, dehydration, deionization, and demicronization to obtain electronic-grade acetone; wherein the purity of the electronic-grade acetone is not less than 99.99%, and wherein the electronic-grade acetone contains: a water content not exceeding 100 ppm, an aldehyde compound content not exceeding 3 ppm, and an evaporation residue content not exceeding 1 ppm.

[0030] Existing technologies do not consider the removal of aldehyde impurities from acetone raw materials. The acetone purification method in this invention can obtain electronic-grade acetone products with a purity of not less than 99.99%, a water content of not more than 100 ppm, an aldehyde compound content of not more than 3 ppm, and an evaporation residue content of not more than 1 ppm, suitable for more demanding semiconductor applications.

[0031] According to the present invention, the acetone content in the crude acetone product is 98.0-99.9% by weight. By using the purification method of the present invention, a higher purity acetone product can be obtained by purifying the aforementioned crude acetone product.

[0032] According to the present invention, the crude acetone contains some other impurities. In some embodiments, the crude acetone also contains at least one of water, C1-C6 alcohols (e.g., methanol, ethanol, isopropanol, butanol, etc.), C1-C6 aldehydes and C2-C6 olefins (e.g., propylene, butene, etc.) and C2-C6 ethers (e.g., diethyl ether, isopropyl ether, etc.).

[0033] According to the present invention, the content of specific impurities in the crude acetone is not particularly limited, for example, the content of C1-C6 alcohols is 0.01-0.50 wt%; the content of C1-C6 aldehydes is 0.002-0.20 wt%; the content of C2-C6 olefins is 0.001-0.10%; and the content of C2-C6 ethers is 0.001-0.20%.

[0034] According to the present invention, as long as the objective of the present invention can be achieved, the amount of the mixed solution used when crude acetone is contacted with a mixed solution containing an oxidant and a strong alkali is not particularly limited. In some preferred embodiments, the mass of the mixed solution is 0.001-0.01 times that of the crude acetone, for example, 0.001 times, 0.002 times, 0.003 times, 0.004 times, 0.005 times, 0.007 times, 0.01 times, or any combination of two of the above values. Using the aforementioned embodiments, crude acetone can be better purified to obtain a high-purity acetone product with low aldehyde content and low water content.

[0035] According to the present invention, a mixed solution containing an oxidant and a strong base refers to a mixed solvent formed by an oxidant, a strong base, and water. In some embodiments, the content of the oxidant in the mixed solution is 0.5-20 wt%, for example, 0.5 wt%, 1 wt%, 2 wt%, 2.5 wt%, 3 wt%, 4 wt%, 5 wt%, 7 wt%, 10 wt%, 15 wt%, 20 wt%, or any range of two of the above values. Using the aforementioned embodiments, crude acetone can be better purified to obtain acetone products with high purity, low aldehyde content, and low water content.

[0036] According to some preferred embodiments of the present invention, the content of the oxidant in the mixed solution is 0.5-10 wt%, preferably 0.5-5 wt%. Using the foregoing embodiments, crude acetone can be better purified to obtain acetone products with high purity, low aldehyde content, and low water content.

[0037] According to the present invention, in some embodiments, the content of strong alkali in the mixed solution is 1-4 mol / L, for example, 1 mol / L, 2 mol / L, 3 mol / L, 4 mol / L, or any two of the above values. By adopting the aforementioned embodiments, crude acetone can be better purified to obtain acetone products with high purity, low aldehyde content, low water content, and low evaporation residue.

[0038] According to the present invention, the type of oxidant is not particularly limited as long as the purpose of the present invention can be achieved. In some embodiments, the oxidant is selected from one or more of neutral oxidants, acidic oxidants and basic oxidants.

[0039] According to some preferred embodiments of the present invention, the oxidant is selected from one or more of potassium permanganate, potassium dichromate, potassium perchlorate, potassium chlorite, potassium chlorate, and potassium hypochlorite.

[0040] According to some preferred embodiments of the present invention, the strong alkali is selected from one or more of sodium hydroxide, potassium hydroxide, and ammonium hydroxide, preferably sodium hydroxide and / or potassium hydroxide. Using the foregoing embodiments, crude acetone can be better purified to obtain acetone products with high purity, low aldehyde content, low water content, and low evaporation residue.

[0041] According to the present invention, in some preferred embodiments, the mixed solution further contains a stabilizer. The stabilizer in this invention refers to a reagent capable of promoting the interaction between the oxidant and strong base in the mixed solution and impurities in the crude acetone, especially aldehyde impurities. In some preferred embodiments, the stabilizer is selected from one or more of sodium pyrophosphate, sodium tripolyphosphate, sodium polyacrylate, sodium polymethacrylate, sodium gluconate, and sodium metasilicate. Using the foregoing embodiments, crude acetone can be better purified to obtain an acetone product with high purity, low aldehyde content, low water content, and low evaporation residue.

[0042] According to some preferred embodiments of the present invention, the stabilizer is selected from sodium pyrophosphate and / or sodium polyacrylate. Using the foregoing embodiments, acetone products with higher purity and lower total aldehyde content, single metal ion content, and evaporation residue content can be obtained.

[0043] According to some preferred embodiments of the present invention, the stabilizer is a combination of sodium pyrophosphate and sodium polyacrylate, preferably with a mass ratio of sodium pyrophosphate to sodium polyacrylate of 1:(1-5), for example 1:1, 1:2, 1:2.5, 1:3, 1:4, 1:5, or any range of two of the above ratios. By adopting the aforementioned embodiments, acetone products with higher purity and lower total aldehyde content, single metal ion content, and evaporation residue content can be obtained.

[0044] According to some preferred embodiments of the present invention, the content of the stabilizer in the mixed solution is 0.5-20 wt%, for example, 0.5 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 13 wt%, 15 wt%, 20 wt%, or any range of two of the above values. Using the aforementioned embodiments, acetone products with higher purity and lower total aldehyde content, single metal ion content, and evaporation residue content can be obtained.

[0045] According to some more preferred embodiments of the present invention, the content of stabilizer in the mixed solution is 1-10 wt%, preferably 2-7 wt%.

[0046] According to the present invention, the method of contacting crude acetone with a mixed solution containing an oxidant and a strong alkali is not particularly limited, as long as the objective of the present invention can be achieved. Preferably, the mixed solution containing the oxidant and the strong alkali is sprayed into the reaction equipment containing the crude acetone for contact with the crude acetone. By employing the aforementioned embodiments, the mixed solution can better interact with impurities in the crude acetone, reducing the impurity content and ultimately refining the acetone product to obtain higher purity with lower total aldehyde content, lower single metal ion content, and lower evaporation residue content.

[0047] In this invention, the reaction equipment for contacting crude acetone with a mixed solution containing an oxidant and a strong base is not particularly limited and can be a conventional stirred tank in the art. In order to spray the mixed solution containing an oxidant and a strong base into the stirred tank containing crude acetone, a spray nozzle can be installed at the bottom of the stirred tank.

[0048] According to the present invention, the contact conditions are not particularly limited as long as the purpose of the present invention can be achieved. Preferably, the contact conditions include: room temperature (20-30°C); preferably, the contact conditions include: a time of 2-7 hours.

[0049] According to the present invention, the purpose of distillation is to remove light and heavy components from the material obtained after contact. In some embodiments, the distillation method includes: distilling the material obtained after contact to remove light and heavy components.

[0050] According to some preferred embodiments of the present invention, the conditions for distillation to remove light substances include: an operating pressure of 100-200 kPa (absolute pressure).

[0051] According to some preferred embodiments of the present invention, the conditions for distillation to remove light components include a reflux ratio of 2-20, for example, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 17, 20, or any two of the above values, preferably 8-15.

[0052] According to the present invention, in some preferred embodiments, the conditions for the distillation and deweighting include: an operating pressure of 100-200 kPa (absolute pressure).

[0053] According to the present invention, in some preferred embodiments, the conditions for the distillation and deweighting include a reflux ratio of 0.2-5.

[0054] According to the present invention, in some preferred embodiments, the conditions for the distillation deweighting include: a column top temperature of 55.7-77.5°C.

[0055] According to the present invention, contacting crude acetone with a mixed solution containing an oxidant and a strong alkali will remove salt impurities. In some preferred embodiments, a desalination step is further included between the distillation to remove light and heavy components. Using the aforementioned embodiments, a higher purity acetone product with lower total aldehyde content, single metal ion content, particulate matter content, and evaporation residue content can be obtained.

[0056] According to the present invention, the desalination method includes centrifugation and / or filtration using a filtration device with a micrometer size of less than 1 micrometer, as long as the purpose of the present invention can be achieved.

[0057] According to the present invention, in some embodiments, the dehydration method includes: pervaporation membrane separation.

[0058] According to the present invention, the pervaporation membrane separation method refers to separation using a membrane. In some preferred embodiments, the membrane in the pervaporation membrane separation method is a molecular sieve membrane.

[0059] According to some preferred embodiments of the present invention, the operating conditions of the pervaporation membrane separation method include: an operating temperature of 80°C-140°C.

[0060] According to some preferred embodiments of the present invention, the operating conditions of the pervaporation membrane separation method include: the operating pressure of the pervaporation membrane separation method is 2-9 bar.

[0061] According to some preferred embodiments of the present invention, the operating conditions of the pervaporation membrane separation method include: the operating pressure on the permeate side is 0-20 kPa (absolute pressure).

[0062] According to the present invention, the method for removing ions is not particularly limited as long as the purpose of the present invention can be achieved. In some embodiments, the method for removing ions includes: ion exchange adsorption removal.

[0063] According to the present invention, the ion exchange adsorption removal method refers to the treatment of materials in an ion tower filled with adsorption material to remove metal cation and anion impurities from the materials. Preferably, the adsorption material used in the ion exchange adsorption removal method includes a mixed bed resin composed of hydrogen-form strong acid cation exchange resin and hydroxide-form strong base anion exchange resin. The mixed bed resin refers to the uniform mixing and filling of hydrogen-form strong acid cation exchange resin and hydroxide-form strong base anion exchange resin in the adsorption tower. The mixed bed resin can remove metal cations and anions from the materials.

[0064] According to some preferred embodiments of the present invention, the departicle removal method includes: filtration.

[0065] According to some preferred embodiments of the present invention, the filter element in the filtration method is made of at least one of PTFE, PVDF and PE.

[0066] According to some preferred embodiments of the present invention, filter elements with at least four progressively increasing filtration accuracies are used in series. For example, PTFE filter elements with filtration specifications of 500nm, 200nm, 100nm and 50nm are used for particle removal.

[0067] According to the present invention, such as Figure 1As shown, in some embodiments, the acetone refining method includes: adding a mixed solution containing an oxidant and a strong base to the industrial-grade crude acetone 1 in a stirred tank ① for contact; the reactant 3 after contact is fed into a distillation column ② for distillation to remove light components; the bottom product 4 of the distillation column ② is first fed into a centrifugal filter ③ for coarse filtration; the obtained coarsely filtered product 5 is fed into a distillation column ④ for distillation to remove heavy components; the top product 6 obtained from the distillation to remove heavy components is fed into a pervaporation membrane device ⑤ for pervaporation membrane separation and dehydration; the concentrated liquid 7 from the pervaporation membrane separation and dehydration is fed into a detachment column ⑥ filled with a mixed bed resin of a uniformly mixed hydrogen-form strong acid cation exchange resin and a hydroxide-form strong base anion exchange resin for detachment; the bottom material 8 of the detachment column ⑥ is fed into a filter device ⑦ for filtration to remove microparticles and obtain acetone product 9.

[0068] The present invention will be described in detail below through examples. In the following examples, the purity of the products was detected by HPLC; the moisture content was determined by Karl Fischer titration; the metal ions were determined by ICP-MS; the particle number was determined by an online particle counter; the aldehyde content (total aldehyde content) was determined by HPLC; and the evaporation residue was determined by the general method of national standard GB / T 9740-2008.

[0069] Example 1

[0070] Add 0.01 times the mass of a mixed solution 2 (solvent is water) containing 1 wt% potassium permanganate, 2 mol / L sodium hydroxide and 2 wt% sodium pyrophosphate to industrial grade crude acetone 1 (purity is 99.0%, total aldehyde content is 35 ppm, water content is 3500 ppm) in a stirred tank ①. After stirring and reacting at room temperature for 5 h, the reaction mixture 3 is fed into a distillation column ② for distillation to remove light components. The operating pressure for distillation is 100 kPa, the operating reflux ratio is 10, and the temperature of the column bottom is controlled at 56.6℃.

[0071] The bottom product 4 of the distillation column ② first enters the centrifugal filtration equipment ③ for coarse filtration, and the obtained coarse filtration product 5 enters the distillation column ④ for distillation to remove heavy weights. The operating pressure of the distillation to remove heavy weights is 100 kPa, the operating reflux ratio is 1, and the temperature at the top of the column is controlled at 55.7℃.

[0072] The overhead product 6 obtained from distillation and deweighting enters the pervaporation membrane equipment ⑤ for pervaporation membrane separation and dehydration. The membrane separation operating temperature is 120℃, the operating pressure is 6 bar, and the operating pressure on the permeate side is 0.1 kPa (absolute pressure).

[0073] The concentrated liquid 7 from membrane separation enters a deionization tower 6 filled with a mixed bed of hydrogen-form strong acid cation exchange resin and hydroxide-form strong base anion exchange resin for deionization. The bottom material 8 of the deionization tower 6 enters a filtration device 7 and undergoes a four-stage series filtration process with PTFE filter elements of 500nm, 200nm, 100nm and 50nm in sequence to remove microparticles, resulting in acetone product 9.

[0074] Example 2

[0075] The method of Example 1 was followed, except that the purity of the industrial grade crude acetone was 98.5%, the total aldehyde content was 240 ppm, and the water content was 8200 ppm; the rest was the same as in Example 1, and the final acetone product was obtained.

[0076] Example 3

[0077] The method of Example 1 was followed, except that the amount of mixed solution added was 0.002 times the mass of the amount of crude acetone added; the rest was the same as in Example 1, and the final acetone product was obtained.

[0078] Example 4

[0079] The method is the same as in Example 1, except that the mixed solution also contains 5 wt% sodium polyacrylate; the mixed solution enters the stirred tank through a nozzle at the bottom of the stirred tank and reacts with crude acetone in the stirred tank for 5 hours; the rest is the same as in Example 1, and finally acetone product is obtained.

[0080] Example 5

[0081] The method of Example 1 was followed, except that the mixed solution also contained 5 wt% sodium polyacrylate; the rest was the same as in Example 1, and acetone was finally obtained.

[0082] Example 6

[0083] The method of Example 1 was followed, except that the mixed solution contained 1 wt% potassium permanganate, 2 mol / L sodium hydroxide and 7 wt% sodium polyacrylate; the rest was the same as in Example 1, and acetone was finally obtained.

[0084] Example 7

[0085] The method is the same as in Example 4, except that:

[0086] The bottom product 4 from the distillation column for removing light components is directly fed into the distillation column for removing heavy components for subsequent steps; the rest is the same as in Example 1, and acetone is finally obtained.

[0087] Comparative Example 1

[0088] The method is the same as in Example 1, except that:

[0089] The mixed solution contained only 1 wt% potassium permanganate; the rest was the same as in Example 1, and acetone was finally obtained.

[0090] Comparative Example 2

[0091] The method of Example 1 was followed, except that the mixed solution contained only 2 mol / L sodium hydroxide; the rest was the same as in Example 1, and acetone was finally obtained.

[0092] Table 1

[0093]

[0094]

[0095] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for refining acetone, characterized by, The method comprises: The crude acetone is contacted with a mixed solution containing an oxidizing agent and a strong base, and then subjected to rectification, dehydration, ion removal, and microparticle removal to obtain an electronic-grade acetone product; The electronic-grade acetone product has a purity of not less than 99.99%, and the electronic-grade acetone product contains water in an amount of not higher than 100 ppm, aldehyde compounds in an amount of not higher than 3 ppm, and evaporation residue in an amount of not higher than 1 ppm; The mixed solution further contains a stabilizer; The stabilizer is selected from one or more of sodium pyrophosphate, sodium tripolyphosphate, sodium polyacrylate, sodium polymethacrylate, sodium gluconate, and sodium metasilicate.

2. The method according to claim 1, wherein, the crude acetone contains acetone in an amount of 98.0-99.9% by weight; and / or the crude acetone further contains at least one of water, C1-C6 alcohols, C1-C6 aldehydes, C2-C6 alkenes, and C2-C6 ethers.

3. The method according to claim 1, wherein, the mixed solution has a mass of 0.001-0.01 times that of the crude acetone; and / or the mixed solution contains the oxidizing agent in an amount of 0.5-20 wt%; and / or the mixed solution contains the strong base in an amount of 1-4 mol / L; and / or the oxidizing agent is selected from one or more of neutral oxidizing agents, acidic oxidizing agents, and basic oxidizing agents; and / or the strong base is selected from one or more of sodium hydroxide, potassium hydroxide, and ammonium hydroxide.

4. The method according to claim 3, wherein, the mixed solution contains the oxidizing agent in an amount of 0.5-10 wt%; and / or the oxidizing agent is selected from one or more of potassium permanganate, potassium dichromate, potassium perchlorate, potassium chlorite, potassium chlorate, and potassium hypochlorite; and / or the strong base is sodium hydroxide and / or potassium hydroxide.

5. The method according to claim 1, wherein, the mixed solution contains the stabilizer in an amount of 0.5-20 wt%.

6. The method according to claim 5, wherein, the mixed solution contains the stabilizer in an amount of 1-10 wt%.

7. The method according to claim 1, wherein, the mixed solution containing the oxidizing agent and the strong base is sprayed to contact the crude acetone; and / or the contacting is performed at room temperature and / or for 2-7 hours.

8. The method according to claim 1, wherein, the rectification method comprises rectification to remove light components and rectification to remove heavy components from the contacted product.

9. The method according to claim 8, wherein, the rectification to remove light components is performed at an operating pressure of 100-200 kPa, a reflux ratio of 2-20, and a column bottom temperature of 56.6-78.0 ℃; and / or the rectification to remove heavy components is performed at an operating pressure of 100-200 kPa, a reflux ratio of 0.2-5, and a column top temperature of 55.7-77.5 ℃; and / or the rectification to remove light components and the rectification to remove heavy components further comprise a desalting treatment step.

10. The method according to claim 9, wherein, the desalting treatment method comprises centrifugation and / or filtration using a filter device with a size of less than 1 micron. ​ 11. The method of claim 1, wherein, the method of dehydrating comprises a pervaporation membrane separation method.

12. The method of claim 11, wherein, the membrane in the pervaporation membrane separation method is a molecular sieve membrane; and / or the operating conditions of the pervaporation membrane separation method comprise: an operating temperature of 80-140°C, and / or an operating pressure of the pervaporation membrane separation method of 2-9 bar; and / or an operating pressure on the permeate side of 0-20 kPa.

13. The method of claim 1, wherein, the method of deionizing comprises an ion exchange adsorption removal method; and / or the method of removing particulates comprises a filtration method.

14. The method of claim 13, wherein, the adsorption material used in the ion exchange adsorption removal method comprises a mixed bed resin composed of a hydrogen type strong acid cation exchange resin and a hydrogen-oxygen type strong base anion exchange resin; and / or the material of the filter core in the filtration method is at least one of PTFE, PVDF, and PE; and / or, filter cores with at least 4 levels of filtration accuracy increasing step by step are used in series.

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