Production method of electronic grade catechol

Abstract

The invention relates to a production method of electronic-grade catechol, which comprises the following steps: stirring, heating and mixing industrial-grade catechol from outside of a boundary and a solvent to prepare a catechol solution, and then sequentially carrying out microfiltration, ion removal, nanofiltration, crystallization and drying to obtain a high-purity catechol product meeting the SEMI C12 standard and above. Compared with the prior art, the method provided by the invention has the advantages of short flow, low energy consumption, good separation effect, strong process continuity, high purity and low impurity content, and can meet the production of high-purity catechol above G4 requirements.

Description

Technical Field

[0001] This invention belongs to the field of electronic-grade catechol production technology, and relates to a method for producing electronic-grade catechol. Background Technology

[0002] With the rapid development of technologies in the semiconductor, battery, and pharmaceutical fields, the requirements for high-purity chemical reagents are becoming increasingly stringent. Their purity and cleanliness have a significant impact on yield, electrical performance, and reliability. High-purity catechol, as an important electronic chemical, is widely used in power batteries, pharmaceuticals, and semiconductors. As integrated circuit processing dimensions enter the nanometer era, even higher requirements are placed on the catechol used in conjunction with it, necessitating compliance with the SEMI C12 standard set by the Semiconductor Equipment and Materials International (SEMI), which specifies a metal cation content of less than 100 ppt.

[0003] There are few research reports on high-quality, high-purity reagents in China; the available information mostly focuses on basic technologies and patents. Internationally, high-purity reagent process routes are considered industry secrets, and many basic technologies are protected by patents.

[0004] Chinese patent application CN202310337953.6 discloses a method for producing the electronic chemical catechol, including a dissolution step, a microfiltration step, an anion and cation removal step, a flash evaporation separation step or a distillation separation step, a nanofiltration step, a crystallization step, and a drying step. Although this patent can obtain catechol that meets the requirements of electronic chemicals G4 and above, the overall process is complex, and steps such as flash evaporation or distillation separation are energy-intensive and involve side reactions. Summary of the Invention

[0005] The purpose of this invention is to provide a method for producing electronic-grade catechol, which has a short process, low energy consumption, good separation effect, strong process continuity, high purity, and low impurity content.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] In one aspect, the present invention provides a method for producing electronic-grade catechol, which involves mixing industrial-grade catechol from outside the boundary with a solvent by stirring and heating to prepare a catechol solution, and then sequentially performing microfiltration, ion removal, nanofiltration, crystallization and drying processes to obtain a high-purity catechol product that meets or exceeds the SEMIC12(G4) standard.

[0008] Furthermore, the solvent is one or a combination of several of the following: water, methanol, ethanol, n-propanol, isopropanol, acetone, methyl acetate, and ethyl acetate, and the molar ratio of the solvent to catechol in the feed is 0.32 to 0.62:1.

[0009] Furthermore, the microfiltration process is carried out in a microfilter to remove particles with a diameter of 0.2 μm or larger.

[0010] Furthermore, the ion removal process involves removing the anions and cations from catechol using ion exchange resin or ion exchange fibers in an anion and cation remover.

[0011] Furthermore, the ion exchange resin is one or more of sulfonated styrene resin, carboxylated styrene resin, quaternary ammonium styrene resin, perfluorosulfonic acid resin, and sulfonated polyethersulfone resin.

[0012] The ion exchange fiber is one or more of the following: sulfonated styrene fiber, carboxylated styrene fiber, quaternary ammonium styrene fiber, perfluorosulfonic acid fiber, and sulfonated polyethersulfone fiber.

[0013] Furthermore, the nanofiltration process is carried out in a nanofilter, where particles larger than 10 nm are filtered out through a nanofiltration membrane.

[0014] Furthermore, the nanofiltration membrane is a polytetrafluoroethylene membrane, polyethersulfone membrane, polyvinylidene fluoride membrane, polyimide membrane, or polyamide membrane with a pore size of 10-50 nm.

[0015] Furthermore, the crystallization process is carried out in a crystallizer at a temperature of 10–100°C. The crystallizer is at least a single-stage crystallizer, preferably a two-stage or higher crystallizer.

[0016] Furthermore, the drying temperature is 70–110°C.

[0017] On the other hand, the present invention provides an apparatus for producing electronic-grade catechol, which is used to implement the production method described above, the apparatus comprising: connected in sequence:

[0018] A stirring and heating mixer is used to prepare the catechol solution;

[0019] Microfilters are used to perform microfiltration processes;

[0020] Anion and cation remover, used to perform ion removal process;

[0021] Nanofilters are used to perform nanofiltration processes;

[0022] A crystallizer is used to perform the crystallization process;

[0023] A dryer is used to perform the drying process.

[0024] While existing technologies such as CN202310337953.6 can also produce catechol products that meet the G4 and above requirements for electronic chemicals, the overall process is complex and cumbersome. Furthermore, current mainstream improvement approaches primarily involve adding processing steps to increase the purity of electronic chemicals. In contrast, this invention optimizes and improves the parameters of each process, eliminating cumbersome and energy-intensive distillation and separation steps. By directly using crystallization and subsequent drying processes in conjunction with pre-processing, it effectively removes impurities such as water and organic impurities. This results in a product with high purity, high process yield, and low impurity content. Moreover, due to the removal of impurities through flash evaporation (distillation) separation, the entire production method exhibits strong process continuity and has significant industrialization potential. In addition, the produced electronic-grade methanol product meets SEMI C12 and above standards. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the production process of electronic-grade high-purity catechol according to the present invention;

[0026] Explanation of markings in the diagram:

[0027] 1-Industrial grade catechol raw material; 2-Solvent; 3-Stirring and heating mixer; 4-Catechol solution; 5-Microfilter; 6-Microfiltered catechol; 7-Anion and cation remover; 8-Deionized catechol; 9-Nanofilter; 10-Nanofiltered catechol; 11-Crystallizer; 12-Crystallization mother liquor; 13-Crystallized catechol product; 14-Dryer; 15-Electronic grade catechol product. Detailed Implementation

[0028] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0029] Unless otherwise specified, the raw materials or processing techniques used in the following embodiments or examples are conventional commercially available raw materials or conventional processing techniques in the art.

[0030] In some embodiments, the present invention provides a method for producing electronic-grade catechol, such as... Figure 1As shown, industrial-grade catechol raw material 1 from outside the boundary area is heated and mixed with solvent 2 in a stirring and heating mixer 3 to prepare catechol solution 4. Then, it enters a microfilter 5 for microfiltration to remove particles larger than 0.2 μm. Next, the microfiltered catechol 6 continues to enter an anion and cation remover 7 for full reaction to remove most of the anions and cations in the catechol, resulting in deionized catechol 8, which enters a nanofilter 9 to filter out particles larger than 10 nm. The obtained nanofiltered catechol 10 is then sent to a crystallizer 11 for full crystallization. The resulting crystallization mother liquor 12 is discharged, and the crystallized catechol product 13 is sent to a dryer 14 for drying to obtain electronic-grade catechol product 15 for output.

[0031] The catechol raw material of this invention is industrial grade catechol with a purity of 99% or higher by mass, a water content of 500 ppm or higher, a metal ion content of 500 ppt or higher, an anion content of 500 ppb or higher, and more than 1000 particles larger than 0.2 μm (micrometers) per ml (milliliters).

[0032] In some specific embodiments, the solvent is one or a combination of several of the following: water, methanol, ethanol, n-propanol, isopropanol, acetone, methyl acetate, and ethyl acetate, and the molar ratio of the solvent to catechol in the feed is 0.32 to 0.62:1.

[0033] In some specific embodiments, the microfiltration process is carried out in a microfilter, where particles with a diameter of 0.2 μm or larger are removed by passing them through a microfiltration membrane. Specifically, the microfiltration membrane can be a polytetrafluoroethylene membrane, a polyethersulfone membrane, a polyvinylidene fluoride (PVDF) membrane, a polyimide membrane, a polyamide membrane, or other membranes with equivalent properties and a pore size of 0.1-0.5 μm (micrometers).

[0034] In some specific embodiments, the ion removal process involves removing the anions and cations from catechol using ion exchange resin or ion exchange fiber in an anion and cation remover.

[0035] Furthermore, the ion exchange resin is one or more of sulfonated styrene resin, carboxylated styrene resin, quaternary ammonium styrene resin, perfluorosulfonic acid resin, and sulfonated polyethersulfone resin.

[0036] The ion exchange fiber is one or more of the following: sulfonated styrene fiber, carboxylated styrene fiber, quaternary ammonium styrene fiber, perfluorosulfonic acid fiber, and sulfonated polyethersulfone fiber.

[0037] In some specific implementations, the nanofiltration process is carried out in a nanofilter, where particles larger than 10 nm are filtered out through a nanofiltration membrane.

[0038] Furthermore, the nanofiltration membrane is a polytetrafluoroethylene membrane, polyethersulfone membrane, polyvinylidene fluoride membrane, polyimide membrane, or polyamide membrane with a pore size of 10-50 nm.

[0039] In some specific implementations, the crystallization process is carried out in a crystallizer at a temperature of 10–100°C.

[0040] In some specific implementations, the drying temperature is 70–110°C.

[0041] Each of the above implementation methods can be implemented individually, or in any combination of two or more.

[0042] The above implementation methods will be described in more detail below with reference to specific embodiments.

[0043] Example 1:

[0044] In such Figure 1 Based on the existing process flow, the specific process parameters in this embodiment are set as follows:

[0045] Catechol and methanol were fed into a stirred mixer at a molar ratio of 0.42:1 and heated to 55°C until homogeneous. The mixture was then fed into a microfilter using a 0.2 μm pore size and a uniformity coefficient of 1.30 PTFE membrane. The ion exchange resin in the anion and cation exchangers was a mixture of sulfonated styrene resin and quaternary ammonium styrene resin with a particle size of 0.6 mm and a uniformity coefficient of 1.05, mixed at a volume ratio of 3:2. The nanofilter used a 20 nm PTFE membrane with a uniformity coefficient of 1.15. Crystallizer 11 employed a two-stage crystallization process, with crystallization temperatures of 25°C and 97°C, respectively. The dryer operated at 75°C, 75 kPa, for 2 hours. A high-purity catechol product exceeding the SEMI C12 (G4) standard was obtained. Product specifications are shown in Table 2.

[0046] Example 2

[0047] In such Figure 1 Based on the existing process flow, the specific process parameters in this embodiment are set as follows:

[0048] The catechol and solvent water were fed at a molar ratio of 0.32 into a stirred mixer and heated to 92°C until homogeneous. The mixture was then fed into a microfilter using a polyimide membrane with a pore size of 0.5 μm and a uniformity coefficient of 1.1. The ion exchange resin was a mixture of perfluorosulfonic acid resin and quaternary ammonium styrene resin prepared at a volume ratio of 2:1, with a particle size of 0.3 mm and a uniformity coefficient of 1.25. A nanofiltration unit used a polyimide membrane with a pore size of 10 nm and a uniformity coefficient of 1.25. A three-stage crystallizer was used, with crystallization temperatures of 30°C, 70°C, and 96°C, respectively. The dryer operated at 90°C, 100 kPa, for 1.5 h. A high-purity catechol product exceeding the SEMI C12 (G4) standard was obtained. Product specifications are shown in Table 2.

[0049] Example 3

[0050] In such Figure 1 Based on the existing process flow, the specific process parameters in this embodiment are set as follows:

[0051] The catechol and isopropanol feed molar ratio of 0.48 were fed into a stirred mixing heater and heated to 55°C until homogeneous. The mixture then entered a microfilter using a polyamide membrane with a pore size of 0.2 μm and a uniformity coefficient of 1.3. The ion exchange resin was a mixture of sulfonated styrene resin and quaternary ammonium styrene resin with a particle size of 0.5 mm and a uniformity coefficient of 1.1, mixed at a volume ratio of 2:3. A nanofiltration unit used a polyvinylidene fluoride (PVDF) membrane with a pore size of 30 nm and a uniformity coefficient of 1.05. A two-stage crystallizer was used, with crystallization temperatures of 30°C and 95°C. The dryer operated at 110°C and 110 kPa for 25 min. High-purity catechol products exceeding the SEMI C12 (G4) standard were obtained. Product specifications are shown in Table 2.

[0052] Example 4

[0053] In such Figure 1 Based on the existing process flow, the specific process parameters in this embodiment are set as follows:

[0054] Catechol and acetone were fed into a stirred mixer at a mass ratio of 0.55, heated to 48°C, and mixed thoroughly before entering a microfilter. The microfilter used a polyimide membrane with a pore size of 0.1 μm and a uniformity coefficient of 1.35. The ion exchange resin was a mixture of perfluorosulfonic acid resin and quaternary ammonium styrene resin with a particle size of 0.6 mm and a uniformity coefficient of 1.05, mixed at a volume ratio of 1:3. The nanofilter used a polyvinylidene fluoride (PVDF) membrane with a pore size of 10 nm and a uniformity coefficient of 1.2. The crystallizer used a three-stage crystallization process with crystallization temperatures of 10°C, 70°C, and 94°C, respectively. The dryer operated at 75°C, 70 kPa, for 1 hour. A high-purity catechol product exceeding the SEMI C12 (G4) standard was obtained. Product specifications are shown in Table 2.

[0055] Example 5

[0056] In such Figure 1 Based on the existing process flow, the specific process parameters in this embodiment are set as follows:

[0057] Catechol and methyl acetate were fed at a molar ratio of 0.50 into a stirred mixer and heated to 60°C until homogeneous. The mixture then entered a microfilter using a polyimide membrane with a pore size of 0.1 μm and a uniformity coefficient of 1.35. The ion exchange resin was a mixture of styrene phosphate resin and quaternary ammonium styrene resin with a particle size of 0.5 mm and a uniformity coefficient of 1.15, mixed at a volume ratio of 3:2. A nanofiltration unit used a polyamide membrane with a pore size of 40 nm and a uniformity coefficient of 1.05. A four-stage crystallizer was used, with crystallization temperatures of 20°C, 40°C, 75°C, and 96°C, respectively. The dryer operated at 95°C, 85 kPa, for 45 min. A high-purity catechol product exceeding the SEMI C12 (G4) standard was obtained. Product specifications are shown in Table 3.

[0058] Example 6

[0059] In such Figure 1 Based on the existing process flow, the specific process parameters in this embodiment are set as follows:

[0060] The catechol and ethyl acetate feed molar ratio of 0.62 was fed into a stirred mixer and heated to 62°C until homogeneous. The mixture then entered a microfilter using a polyamide membrane with a pore size of 0.2 μm and a uniformity coefficient of 1.3. The ion exchange resin was a mixture of perfluorosulfonic acid resin and quaternary ammonium styrene resin with a particle size of 0.4 mm and a uniformity coefficient of 1.25, mixed at a volume ratio of 2:3. The nanofilter used a polytetrafluoroethylene membrane with a pore size of 50 nm and a uniformity coefficient of 1.05. A two-stage crystallizer was used, with crystallization temperatures of 35°C and 95°C, respectively. The dryer operated at 70°C, 40 kPa, for 2.5 h. A high-purity catechol product exceeding the SEMI C12 (G4) standard was obtained. Product specifications are shown in Table 3.

[0061] Comparative Example 1

[0062] This comparative example uses the same raw materials and process as Example 1, the difference being that the particle size uniformity coefficient of the ion exchange resin used in the ion exchange remover is changed to 1.4. Product specifications are shown in Table 3. Sodium, potassium, boron, and silicon do not meet the SEMIC12 (G4) requirements; sodium, iron, copper, calcium, potassium, boron, silicon, zinc, lead, arsenic, and cobalt do not meet the SEMI C12 (G5) requirements.

[0063] Comparative Example 2

[0064] This comparative example uses the same raw materials and process as Example 1, the difference being that the ion exchange resin particle size used in the ion exchange remover is changed to 0.7 mm. Product specifications are shown in Table 3. Sodium, potassium, boron, and silicon do not meet the SEMI C12 (G4) requirements; sodium, iron, copper, calcium, lead, potassium, boron, silicon, magnesium, zinc, arsenic, aluminum, cadmium, silver, tin, titanium, and cobalt do not meet the G5 requirements.

[0065] Comparative Example 3

[0066] The feed and operating conditions for this comparative example are exactly the same as those for Example 1, except that the crystallizer is changed from a two-stage to a single-stage process, and the drying temperature is 145°C. The product specifications are shown in Table 3. The product purity does not meet the requirements of SEMI C12(G4).

[0067] The content of components in the catechol products of Examples 1-6 and Comparative Examples 1-3 was determined. The instruments used for detection were: PerkinElmer ICP-OES / Avio 550MAX for raw material cations, Agilent ICP-MS / MS 8900 for product cations, Metrohm 940 ion chromatograph for raw materials and products, a Coulomb 851 cassette water analyzer for water content in raw materials and products, Agilent GC-MS for organic impurities in raw materials and products, and RION-KS-42AF for particle size analysis. The results are shown in Tables 1-4. The raw materials in Table 1 refer to industrial-grade catechol.

[0068] Table 1. Indicators of catechol raw materials

[0069]

[0070] Table 2 Product indicators obtained from Examples 1 to 4 of the present invention

[0071]

[0072]

[0073] Table 3 shows the product indicators obtained after processing in Examples 5 and 6.

[0074]

[0075]

[0076] Table 4 shows the product indicators processed by Comparative Examples 1 to 3.

[0077]

[0078]

[0079] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for producing electronic-grade catechol, characterized in that, Industrial-grade catechol from outside the designated area is mixed with a solvent by stirring and heating to prepare a catechol solution. Then, the solution undergoes microfiltration, ion removal, nanofiltration, crystallization, and drying processes to obtain a high-purity catechol product that meets or exceeds the SEMIC 12 standard.

2. The method for producing electronic-grade catechol according to claim 1, characterized in that, The solvent is one or a combination of several of the following: water, methanol, ethanol, n-propanol, isopropanol, acetone, methyl acetate, and ethyl acetate. The molar ratio of the solvent to catechol in the feed is 0.32 to 0.62:

1.

3. The method for producing electronic-grade catechol according to claim 1, characterized in that, The microfiltration process is carried out in a microfilter to remove particles with a diameter of 0.2 μm or larger.

4. The method for producing electronic-grade catechol according to claim 1, characterized in that, The ion removal process involves removing the anions and cations from catechol using ion exchange resin or ion exchange fibers in an anion and cation remover.

5. The method for producing electronic-grade catechol according to claim 4, characterized in that, The ion exchange resin is one or more of sulfonated styrene resin, carboxylated styrene resin, quaternary ammonium styrene resin, perfluorosulfonic acid resin, and sulfonated polyethersulfone resin, and the particle size of the ion exchange resin is 0.3-0.6 mm. The ion exchange fiber is one or more of the following: sulfonated styrene fiber, carboxylated styrene fiber, quaternary ammonium styrene fiber, perfluorosulfonic acid fiber, and sulfonated polyethersulfone fiber.

6. The method for producing electronic-grade catechol according to claim 1, characterized in that, The nanofiltration process is carried out in a nanofilter, where particles larger than 10 nm are filtered out through a nanofiltration membrane.

7. The method for producing electronic-grade catechol according to claim 6, characterized in that, The nanofiltration membrane is a polytetrafluoroethylene membrane, polyethersulfone membrane, polyvinylidene fluoride membrane, polyimide membrane, or polyamide membrane with a pore size of 10-50 nm.

8. The method for producing electronic-grade catechol according to claim 1, characterized in that, The crystallization process is carried out in a crystallizer, which is at least a single stage, and the temperature of each stage of crystallization is 10 to 100°C.

9. The method for producing electronic-grade catechol according to claim 1, characterized in that, The drying temperature is 70–110℃.

10. An apparatus for producing electronic-grade catechol, used to implement the production method as described in any one of claims 1-9, characterized in that, The production apparatus comprises, in sequence, the following: A stirring and heating mixer is used to prepare the catechol solution; Microfilters are used to perform microfiltration processes; Anion and cation remover, used to perform ion removal process; Nanofilters are used to perform nanofiltration processes; A crystallizer is used to perform the crystallization process; A dryer is used to perform the drying process.

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