Purification process of carboxybenzotriazole

Abstract

The invention discloses a purification process of carboxybenzotriazole, which comprises the following steps: when the content of metal ions in a carboxybenzotriazole raw material is higher than 50ppm, purifying carboxybenzotriazole by adopting a recrystallization method and an electrolytic method in sequence; and when the content of metal ions in the carboxyl benzotriazole raw material is below 50ppm, purifying the carboxyl benzotriazole by adopting an electrolytic method. According to the purity of metal ions in the carboxyl benzotriazole raw material, a proper purification process is selected, the operation is simple and easy to implement, the raw materials are wide and easy to obtain, the treatment capacity is large, the cost is low, the high removal rate of metal impurity ions is effectively ensured and can reach 95% or above, and the content of various impurity metal ions is reduced to 10 ppb or below; the product yield is 90% or above, the product purity is remarkably improved and can reach 99.99% or above, and the standard of electronic-grade products can be met through one-time electrolysis.

Description

Technical Field

[0001] The present invention relates to the technical field of purification of carboxybenzotriazole, and specifically relates to a purification process of carboxybenzotriazole. Background Art

[0002] In recent years, the production capacity of high-tech industries such as integrated circuits, new energy vehicles, and high computing power has shown an accelerating trend of transferring to China. This transfer not only drives the vigorous development of related industrial chains, but also poses new challenges and requirements in many aspects such as raw material supply, product quality control, cost control, and technological innovation. Among many key raw materials, carboxybenzotriazole (CBT), as an organic corrosion inhibitor with excellent performance, shows broad application potential in the field of metal protection due to its excellent anti-corrosion ability. CBT can effectively protect various metals such as copper, iron, and aluminum from deterioration or damage due to environmental factors (such as humidity, temperature, chemical corrosion, etc.). In addition, CBT is also one of the key components in wet electronic chemicals. Especially in the process of chip manufacturing and packaging, it plays an irreplaceable role in key processes such as etching and cleaning.

[0003] However, with the development of the semiconductor industry towards higher precision and higher integration, higher requirements are put forward for the purity and quality of CBT. The carboxylic acid group in the CBT molecule has strong complexing ability and can form stable complexes with various metal ions (such as sodium ions, potassium ions, magnesium ions, iron ions, etc.). The presence of these metal ions not only affects the purity of CBT, but may also have an adverse impact on chemical reactions and physical properties in the chip manufacturing process, thereby reducing the performance and reliability of the chip. Therefore, in the field of high-end chip manufacturing, CBT must undergo strict purification treatment to remove these harmful metal ions. Although traditional purification methods can achieve the purification of CBT to a certain extent, they often have problems such as low efficiency, high cost, and large environmental impact, and are difficult to meet the current semiconductor industry's requirements for high-quality, low-cost, and environmentally friendly CBT.

[0004] Therefore, for the purification technology of CBT, there is an urgent need to develop a new method that is efficient, economical, and environmentally friendly to meet the increasing high-quality requirements of CBT in industries such as integrated circuits, new energy vehicles, and high computing power. Summary of the Invention

[0005] To solve the above technical problems, the purpose of the present invention is to provide a purification process of carboxybenzotriazole, which selects a suitable purification process according to the purity of metal ions in the carboxybenzotriazole raw material to obtain electronic-grade carboxybenzotriazole.

[0006] The above object of the present invention is achieved by the following technical solutions:

[0007] A purification process for carboxybenzotriazole. When the content of metal ions in the carboxybenzotriazole (CBT) raw material is higher than 50 ppm, the recrystallization method and the electrolysis method are successively used for the purification of carboxybenzotriazole; when the content of metal ions in the carboxybenzotriazole raw material is below 50 ppm, the electrolysis method is used for the purification of carboxybenzotriazole;

[0008] The recrystallization method includes the following steps: dispersing the carboxybenzotriazole raw material in water, adding a basic pH regulator to the obtained carboxybenzotriazole dispersion, filtering once, adding an acidic pH regulator to the obtained filtrate, filtering twice, and drying the obtained filter residue to obtain recrystallized carboxybenzotriazole;

[0009] The electrolysis method includes the following steps: dispersing the carboxybenzotriazole raw material or the recrystallized carboxybenzotriazole in water, adding a basic pH regulator to the obtained carboxybenzotriazole dispersion to obtain a basic carboxybenzotriazole solution; electrolyzing using an electrolytic cell, the electrolytic cell consists of a cell body, an anode and a cathode, an anion exchange membrane is used to separate the anode chamber and the cathode chamber, adding the basic carboxybenzotriazole solution to the cathode chamber of the electrolytic cell, adding water to the anode chamber of the electrolytic cell, energizing the anode and the cathode, and performing an electrolysis reaction under a voltage condition of 50 - 100 V. After the electrolysis reaction ends, electronic-grade carboxybenzotriazole is collected in the anode chamber.

[0010] The present invention selects a suitable purification process according to the purity of metal ions in the carboxybenzotriazole raw material, overcomes the problems that the purity of the sample obtained by the recrystallization method fails to meet the requirements, the content of impurity metal ions is too high, and the electrolysis method has problems such as low efficiency and high cost due to the loading limit of the ion exchange membrane, and proposes a low-cost, simple, efficient, green and pollution-free purification process for carboxybenzotriazole. When the content of metal ions in the carboxybenzotriazole raw material is higher than 50 ppm, the recrystallization method and the electrolysis method are successively used for the purification of carboxybenzotriazole, and the recrystallization method can first reduce the content of various impurity metal ions; when the content of metal ions in the carboxybenzotriazole raw material is below 50 ppm, the electrolysis method is used for the purification of carboxybenzotriazole, and the content of various impurity metal ions can be reduced to below 10 ppb.

[0011] Further, in the recrystallization method, the concentration of the carboxybenzotriazole raw material in the carboxybenzotriazole dispersion is 1 - 95 wt%.

[0012] Further, in the recrystallization method, the basic pH regulator can be an organic base and / or an inorganic base, and the basic pH regulator is selected from one or more of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, cesium hydroxide, monoethanolamine, diethanolamine, triethanolamine, methylamine, ethylamine, propylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, triethylamine, diethylenetriamine, sodium ethoxide, and potassium tert-butoxide.

[0013] Further, in the recrystallization method, the mass ratio of the basic pH regulator to the carboxybenzotriazole dispersion is (0.1 - 20):100.

[0014] Further, in the recrystallization method, the pore size of the filter membrane used for the primary filtration is 1 - 10 μm.

[0015] Further, in the recrystallization method, the acidic pH regulator can be an organic acid and / or an inorganic acid, and the acidic pH regulator is selected from one or more of hydroxy sulfonic acid compounds, hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, hydrobromic acid, hydroiodic acid, hypochlorous acid, perchloric acid, phosphoric acid, formic acid, acetic acid, propionic acid, benzenesulfonic acid, aminosulfonic acid, methanesulfonic acid, citric acid, tartaric acid, and lactic acid, preferably hydroxy sulfonic acid compounds.

[0016] Sulfonic acid compounds are strong acid compounds, which can effectively reduce the pH and promote the precipitation of CBT. At the same time, hydroxy sulfonic acid compounds have good water solubility, and during the precipitation of CBT, hydroxy sulfonic acid compounds will not precipitate and affect the purity of the target product.

[0017] Further, the hydroxy sulfonic acid compounds are selected from one or more of 3-hydroxy-1-propanesulfonic acid, 3-hydroxybenzenesulfonic acid, 2-hydroxybenzenesulfonic acid, and 2,5-dihydroxybenzenesulfonic acid.

[0018] Further, in the recrystallization method, the mass ratio of the acidic pH regulator to the filtrate is (0.1 - 20):100.

[0019] Further, in the recrystallization method, the pore size of the filter membrane used for the secondary filtration is 1 - 10 μm.

[0020] Further, in the recrystallization method, the drying treatment is vacuum drying treatment.

[0021] Further, in the recrystallization method, the temperature of the drying treatment is 30 - 100 °C, and the time is 8 - 24 h.

[0022] In a specific embodiment, the recrystallization method includes the following steps: dispersing the CBT raw material in water, where the CBT raw material has poor solubility in water, adding a basic pH regulator to the obtained CBT dispersion to completely dissolve the CBT, filtering once to remove insoluble particulate impurities, adding an acidic pH regulator to the obtained filtrate, filtering twice, and drying the obtained filter residue to obtain recrystallized carboxybenzotriazole.

[0023] Further, in the electrolysis method, the concentration of the carboxybenzotriazole raw material or the recrystallized carboxybenzotriazole in the carboxybenzotriazole dispersion is 1-95 wt%.

[0024] Further, in the electrolysis method, the basic pH regulator can be an organic base and / or an inorganic base, and the basic pH regulator is selected from one or more of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, cesium hydroxide, monoethanolamine, diethanolamine, triethanolamine, methylamine, ethylamine, propylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, triethylamine, diethylenetriamine, sodium ethoxide, and potassium tert-butoxide.

[0025] Further, in the electrolysis method, the mass ratio of the basic pH regulator to the carboxybenzotriazole dispersion is (0.1-20):100.

[0026] Further, in the electrolysis method, an H-type electrolytic cell can be used.

[0027] Further, in the electrolysis method, the material of the cell body of the electrolytic cell is selected from one or more of PFA (soluble polytetrafluoroethylene), PTFE (Teflon), PP (polypropylene), PPN, PVDF (polyvinylidene fluoride), and HDPE (high-density polyethylene).

[0028] Further, in the electrolysis method, the cell body of the electrolytic cell is divided into a cathode chamber and an anode chamber, and an anion exchange membrane is used to separate the anode chamber and the cathode chamber. An anode is placed in the anode chamber, and a cathode is placed in the cathode chamber.

[0029] Further, in the electrolysis method, the anode of the electrolytic cell is selected from inert material electrodes such as carbon electrodes, gold electrodes, silver electrodes, and platinum electrodes.

[0030] Further, in the electrolysis method, the cathode of the electrolytic cell is selected from inert material electrodes such as carbon electrodes, gold electrodes, silver electrodes, and platinum electrodes.

[0031] Further, in the electrolysis method, both the anode chamber and the cathode chamber are connected to a pneumatic diaphragm pump, and the pneumatic diaphragm pump is used to accelerate the liquid flow.

[0032] Further, in the electrolysis method, after the electrolysis reaction ends, the mixture in the anode chamber is filtered, and the obtained filter residue is dried to obtain electronic-grade carboxybenzotriazole.

[0033] Further, the pore size of the filter membrane used for the filtration is 1-10 μm.

[0034] Further, in the electrolysis method, before the electrolysis, it also includes the step of cleaning the electrolytic cell with water to remove possible residual metal ion contamination in the electrolytic cell.

[0035] In the specific embodiment, when the content of metal ions in the CBT raw material is higher than 50 ppm, the recrystallization method and the electrolysis method are successively used for the purification of CBT, which specifically includes the steps of the first alkali dissolution, the first filtration, adding acid, the second filtration, the first drying, the second alkali dissolution, electrolysis, the third filtration and the second drying.

[0036] In the specific embodiment, when the content of metal ions in the CBT raw material is below 50 ppm, the electrolysis method is used for the purification of CBT, which specifically includes the steps of alkali dissolution, electrolysis, filtration and drying.

[0037] Advantages of the present invention:

[0038] The purification process of carboxybenzotriazole provided by the present invention is simple and easy to operate, the raw materials are widely available, the processing capacity is large, the cost is low, effectively ensuring a high removal rate of metal impurity ions, up to more than 95%, and the content of various impurity metal ions is reduced to below 10 ppb; the product yield is above 90%, and the product purity is significantly improved, up to more than 99.99%, and the standard of electronic-grade products can be achieved by one electrolysis. At the same time, the waste water and waste gas generated in the process can be treated in a green and environmental protection manner, effectively reducing the negative impact on the environment. Description of the drawings

[0039] Figure 1 It is a schematic diagram of the electrolysis principle in the purification process of carboxybenzotriazole provided by the present invention. Specific embodiments

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0041] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it. However, the exemplified embodiments are not intended to limit the present invention.

[0042] Unless otherwise specified, the experimental methods used in the following embodiments are all conventional methods. The materials, reagents, etc. used, unless otherwise specified, can all be obtained from commercial channels.

[0043] The water used in the following embodiments is ultrapure water with an impurity ion content of less than 1 ppb.

[0044] When testing the content in the following embodiments, ICP-OES (Inductively Coupled Plasma Optical Emission Spectrometer) is selected for the ppm level, and ICP-MS (Inductively Coupled Plasma Mass Spectrometer) is selected for the ppb level. The test instrument used is Agilent.

[0045] The present invention provides a purification process for carboxybenzotriazole. When the metal ion content in the carboxybenzotriazole raw material is higher than 50 ppm, the recrystallization method and the electrolysis method are successively used for the purification of carboxybenzotriazole; when the metal ion content in the carboxybenzotriazole raw material is below 50 ppm, the electrolysis method is used for the purification of carboxybenzotriazole.

[0046] The recrystallization method includes the following steps: dispersing the carboxybenzotriazole raw material in water, adding a basic pH regulator to the obtained carboxybenzotriazole dispersion, filtering once, adding an acidic pH regulator to the obtained filtrate, filtering twice, and drying the obtained filter residue to obtain recrystallized carboxybenzotriazole.

[0047] The electrolysis method includes the following steps: dispersing the carboxybenzotriazole raw material or the recrystallized carboxybenzotriazole in water, adding a basic pH regulator to the obtained carboxybenzotriazole dispersion to obtain a carboxybenzotriazole basic solution; performing electrolysis using an electrolytic cell. The electrolytic cell consists of a cell body, an anode, and a cathode. An anion exchange membrane is used to separate the anode chamber and the cathode chamber. The carboxybenzotriazole basic solution is added to the cathode chamber of the electrolytic cell, water is added to the anode chamber of the electrolytic cell, the anode and the cathode are energized, and an electrolysis reaction is carried out under a voltage condition of 50 - 100 V. After the electrolysis reaction ends, electronic-grade carboxybenzotriazole is collected in the anode chamber.

[0048] In an embodiment of the present invention, the electrolytic cell is cleaned with water before electrolysis to remove possible residual metal ion contamination inside, and after detecting with ICP-MS to ensure that the metal ion content in the waste water after cleaning is less than 1 ppb, the subsequent electrolysis process is carried out.

[0049] In one embodiment of the present invention, in the electrolysis method, the basic pH regulator can be an organic base and / or an inorganic base, and the basic pH regulator is selected from one or more of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, cesium hydroxide, monoethanolamine, diethanolamine, triethanolamine, methylamine, ethylamine, propylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, triethylamine, diethylenetriamine, sodium ethoxide, and potassium tert-butoxide.

[0050] In one embodiment of the present invention, in the electrolysis method, when the basic pH regulator is an amine-based basic pH regulator, a basic pH regulator is added to the obtained carboxybenzotriazole dispersion liquid, and the obtained carboxybenzotriazole basic solution is an aqueous solution of CBT·NH3.

[0051] In one embodiment of the present invention, in the electrolysis method, 3-5 L of an aqueous solution of CBT·NH3 with a concentration of 15-25 wt% is added to the cathode chamber, 3-5 L of water is added to the anode chamber, and then the anode and the cathode are energized, with the voltage between 50-100 V. After energization, the water undergoes an oxidation reaction to generate a large number of electrons. The schematic diagram of the electrolysis principle is as Figure 1 shown, and the specific reaction equations are as follows:

[0052] Anode: 4OH - →2H2O + O2↑ + 4e -

[0053] Cathode: 4H + + 4e - →2H2↑

[0054] A large number of OH - in the anode chamber are electrolyzed to generate oxygen, leaving a large number of H + , and a large number of electrons are generated. In the cathode chamber, CBT·NH3 in the aqueous solution of CBT·NH3 loses NH4 + and becomes CBT - , and combines with a large number of H + in the anode chamber through the anion exchange membrane to form CBT molecules and precipitate. Among them, NH4 + and metal ions such as sodium, potassium, and calcium cannot pass through the anion exchange membrane and remain in the cathode chamber, and NH4 + will form ammonia and water with OH - in the cathode chamber. By heating, the ammonia volatilizes and enters the recovery device. After the deposition of CBT solids in the anode chamber significantly no longer increases, the CBT solid product is collected, and the yield is above 90%.

[0055] In the electrolytic cell used in the following examples, the sizes of the cathode chamber and the anode chamber are both about 30 L, and the anion exchange membrane is selected as DuPont TMAmberLite TM series, the cathode is a platinum electrode, and the anode is a platinum electrode.

[0056] In the following examples, the drying oven is selected from Thermo Fisher Scientific.

[0057] In the following examples, the raw material of carboxybenzotriazole is purchased from manufacturers A and B, and the sample purity is greater than 99.9%. The content of impurity metal ions is shown in Table 1:

[0058] Table 1 Content table of impurity metal ions (unit: ppb)

[0059] raw material Na K Mg Al Fe Ca Ni Mn A 105800 2360 535 302 6430 1560 133 150 B 239400 1580 683 155 2680 982 268 166

[0060] Example 1

[0061] A purification process of carboxybenzotriazole, comprising the following steps:

[0062] (1) Select CBT raw material A, add ultrapure water, and the concentration of CBT raw material A in the obtained CBT dispersion is 20 wt%. Add ammonia water to the CBT dispersion, and the mass ratio of the ammonia water to the CBT dispersion is 10:100. After stirring, dissolve it in an alkaline environment, filter it with a filter membrane with a pore size of 5 μm, then add 3-hydroxy-1-propanesulfonic acid to the filtrate, and the mass ratio of 3-hydroxy-1-propanesulfonic acid to the filtrate is 15:100. After stirring, precipitate it under acidic conditions, then filter it with a filter membrane with a pore size of 5 μm, collect the solid on the filter membrane, put it into a drying oven at 50 °C, and vacuum dry it for 12 hours to obtain the recrystallized CBT solid powder.

[0063] (2) Disperse the recrystallized CBT solid powder in water, and the concentration of CBT in the obtained CBT dispersion is 20 wt%. Add ammonia water to the CBT dispersion, and the mass ratio of the ammonia water to the CBT dispersion is 10:100. After stirring, dissolve it in an alkaline environment, filter it with a filter membrane with a pore size of 5 μm, adopt an H-type electrolytic cell, pour the filtered CBT·NH3 aqueous solution into the cathode chamber, and start electrolysis with a voltage of 60 V at this time. Collect the electrolysis products in the anode chamber, filter them with a filter membrane with a pore size of 5 μm, collect the solid on the filter membrane, put it into a drying oven at 50 °C, and vacuum dry it for 12 hours to finally form an electronic-grade carboxybenzotriazole solid powder with metal impurity ions less than 10 ppb.

[0064] Example 2

[0065] A purification process of carboxybenzotriazole, comprising the following steps:

[0066] (1) Select CBT raw material B, add ultrapure water to obtain a CBT dispersion with a concentration of 20 wt% of CBT raw material B. Add ammonia water to the CBT dispersion, and the mass ratio of the ammonia water to the CBT dispersion is 15:100. After stirring, it is dissolved in an alkaline environment, filtered through a filter membrane with a pore size of 5 μm, and then 3-hydroxy-1-propanesulfonic acid is added to the filtrate. The mass ratio of 3-hydroxy-1-propanesulfonic acid to the filtrate is 10:100. After stirring, it precipitates under acidic conditions, and then is filtered through a filter membrane with a pore size of 5 μm. The solid on the filter membrane is collected, placed in a drying oven at 80 °C, and vacuum dried for 8 hours to obtain the recrystallized CBT solid powder.

[0067] (2) Disperse the recrystallized CBT solid powder in water to obtain a CBT dispersion with a concentration of 20 wt% of CBT. Add ammonia water to the CBT dispersion, and the mass ratio of the ammonia water to the CBT dispersion is 15:100. After stirring, it is dissolved in an alkaline environment, filtered through a filter membrane with a pore size of 5 μm. Then pour the filtered CBT·NH3 aqueous solution into the cathode chamber, and start electrolysis with a voltage of 80 V at this time. Collect the electrolysis products in the anode chamber, filter through a filter membrane with a pore size of 5 μm, collect the solid on the filter membrane, place it in a drying oven at 80 °C, and vacuum dry for 8 hours to finally form an electronic-grade carboxybenzotriazole solid powder with metal impurity ions less than 10 ppb.

[0068] Example 3

[0069] A purification process of carboxybenzotriazole is basically the same as that in Example 1, except that 3-hydroxy-1-propanesulfonic acid is replaced by sulfuric acid.

[0070] Example 4

[0071] A purification process of carboxybenzotriazole is basically the same as that in Example 2, except that 3-hydroxy-1-propanesulfonic acid is replaced by sulfuric acid.

[0072] Test Example

[0073] Test the contents of impurity metal ions and the product yield of the CBT raw materials in Test Examples 1-4 after recrystallization and electrolysis. The test results are shown in Tables 2, 3, 4, 5 and 6:

[0074] Table 2 Content table of impurity metal ions in CBT after recrystallization (unit: ppb)

[0075]

[0076] Table 3 Content table of impurity metal ions in CBT after electrolysis (unit: ppb)

[0077]

[0078]

[0079] Table 4 Content Table of Impurity Metal Ions in CBT after Recrystallization (Unit: ppb)

[0080]

[0081] Table 5 Content Table of Impurity Metal Ions in CBT after Electrolysis (Unit: ppb)

[0082]

[0083]

[0084] Table 6 Data Table of Product Yield

[0085]

[0086] It can be seen from Table 2 to Table 6 that primary recrystallization can remove most of the metal impurity ions, but it cannot meet the requirements of the electronic grade and still needs to be combined with the electrolysis method; the present invention effectively ensures a high removal rate of metal impurity ions, which can reach more than 95%, and the content of various impurity metal ions is reduced to less than 10 ppb, significantly improving the product purity, which can reach more than 99.99%. The standard of electronic grade products can be achieved by one electrolysis.

[0087] Obviously, the above-mentioned embodiments of the present invention are only examples for clearly explaining the present invention, rather than limiting the implementation manners of the present invention. Those skilled in the art should understand that other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A purification process for carboxybenzotriazole, characterized in that: When the content of metal ions in the carboxybenzotriazole raw material is higher than 50ppm, the carboxybenzotriazole is purified by recrystallization and electrolysis in sequence; when the content of metal ions in the carboxybenzotriazole raw material is lower than 50ppm, the carboxybenzotriazole is purified by electrolysis; The recrystallization method comprises the following steps: dispersing a carboxybenzotriazole raw material in water, adding an alkaline pH regulator to the obtained carboxybenzotriazole dispersion, adding an acidic pH regulator to the obtained filtrate after primary filtration, and drying the obtained filter residue after secondary filtration to obtain recrystallized carboxybenzotriazole; The electrolysis method comprises the following steps: dispersing carboxybenzotriazole raw material or recrystallized carboxybenzotriazole in water, adding an alkaline pH regulator to the obtained carboxybenzotriazole dispersion to obtain a carboxybenzotriazole alkaline solution; performing electrolysis in an electrolytic cell, wherein the electrolytic cell is composed of a cell body, an anode and a cathode, and an anion exchange membrane is used to separate the anode chamber and the cathode chamber, adding the carboxybenzotriazole alkaline solution to the cathode chamber of the electrolytic cell, adding water to the anode chamber of the electrolytic cell, energizing the anode and the cathode, performing an electrolytic reaction under a voltage condition of 50-100V, and collecting electronic-grade carboxybenzotriazole in the anode chamber after the electrolytic reaction is completed.

2. The purification process according to claim 1, characterized in that In the recrystallization method, the concentration of the carboxybenzotriazole raw material in the carboxybenzotriazole dispersion is 1-95 wt %.

3. The purification process according to claim 1, characterized in that In the recrystallization method, the alkaline pH regulator is an organic base and / or an inorganic base, and the alkaline pH regulator is selected from one or more of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, cesium hydroxide, monoethanolamine, diethanolamine, triethanolamine, methylamine, ethylamine, propylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, triethylamine, diethylenetriamine, sodium ethoxide and potassium tert-butoxide.

4. The purification process according to claim 1, characterized in that In the recrystallization method, the mass ratio of the alkaline pH regulator to the carboxybenzotriazole dispersion is (0.1-20):

100.

5. The purification process according to claim 1, characterized in that In the recrystallization method, the pore size of the filter membrane used in the primary filtration is 1-10 μm.

6. The purification process according to claim 1, characterized in that: In the recrystallization method, the acidic pH regulator is an organic acid and / or an inorganic acid, and the acidic pH regulator is selected from one or more of hydroxysulfonic acid compounds, hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, hydrobromic acid, hydroiodic acid, hypochlorous acid, perchloric acid, phosphoric acid, formic acid, acetic acid, propionic acid, benzenesulfonic acid, aminosulfonic acid, methanesulfonic acid, citric acid, tartaric acid and lactic acid.

7. The purification process according to claim 6, characterized in that The hydroxysulfonic acid compound is selected from one or more of 3-hydroxy-1-propanesulfonic acid, 3-hydroxybenzenesulfonic acid, 2-hydroxybenzenesulfonic acid and 2,5-dihydroxybenzenesulfonic acid.

8. The purification process according to claim 1, characterized in that: In the recrystallization method, the mass ratio of the acidic pH regulator to the filtrate is (0.1-20):

100.

9. The purification process according to claim 1, characterized in that: In the electrolysis method, the alkaline pH regulator is an organic base and / or an inorganic base, and the alkaline pH regulator is selected from one or more of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, cesium hydroxide, monoethanolamine, diethanolamine, triethanolamine, methylamine, ethylamine, propylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, triethylamine, diethylenetriamine, sodium ethoxide and potassium tert-butoxide.

10. The purification process according to claim 1, characterized in that: In the electrolysis method, after the electrolysis reaction is completed, the mixture in the anode chamber is filtered, and the obtained filter residue is dried to obtain electronic grade carboxybenzotriazole.

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