A method for purifying a basic resin, a basic resin, an anion exchange membrane, and applications thereof

Abstract

This application provides a method for purifying an alkaline resin, the alkaline resin, anion exchange membrane, and their applications. The purification method includes: mixing crude alkaline resin with a first alcohol ether solvent to obtain a first mixture, wherein the flash point of the first alcohol ether solvent is greater than 60°C; and performing a first separation on the first mixture to obtain purified alkaline resin. This purification method uses a highly safe processing solution, is not subject to law enforcement regulations, and can deeply remove impurities from the crude alkaline resin. The resulting purified alkaline resin has a significantly reduced amount of residual impurities. When used in electrochemical systems such as electrolyzers, fuel cells, and flow batteries, it can significantly improve ion exchange rate, reduce internal resistance, and enhance the operational stability of electrochemical devices.

Description

Technical Field

[0001] This application relates to the field of basic resins, and more particularly to a method for purifying basic resins, basic resins, anion exchange membranes, and their applications. Background Technology

[0002] Alkaline resins are key functional materials in water treatment, electrochemical energy, and other fields. The treatment of impurities after synthesis significantly affects the resin's purity and application performance. Currently, the industry commonly uses a precipitation-washing combined process to purify crude alkaline resins. For example, resin is precipitated with solvents such as diethyl ether and acetone, followed by centrifugal washing with ethyl acetate, and finally washing with water and drying to obtain the finished product. However, this process has significant drawbacks: First, diethyl ether and acetone are precursor chemicals for toxic substances, subject to strict regulations, high compliance costs, and significant legal risks. Second, these solvents are all low-flash-point flammable materials, posing extremely high flammability and explosion risks, requiring high-level explosion-proof equipment or inert protection, resulting in high production costs. Furthermore, the solvents are highly volatile, leading to significant losses, heavy pollution, and jeopardizing operational safety. Third, traditional solvents have weak penetration, making it difficult to deeply remove residual impurities within the resin micropores, resulting in low resin purity, poor membrane interface performance, and significantly reduced ion conduction efficiency and operational stability. Therefore, there is an urgent need to develop a compliant, safe, and efficient alkaline resin post-treatment technology. Summary of the Invention

[0003] In view of this, the present application provides a purification method for alkaline resin, alkaline resin, anion exchange membrane and its application. This method overcomes the compliance risks and safety hazards of traditional solvents, optimizes the intrinsic properties of alkaline resin through deep impurity removal, and provides a material basis for the stable operation of high-performance electrochemical devices such as electrolyzers, fuel cells and flow batteries.

[0004] In a first aspect, embodiments of this application provide a method for purifying an alkaline resin, comprising the following steps: mixing crude alkaline resin with a first alcohol ether solvent to obtain a first mixture, wherein the flash point of the first alcohol ether solvent is greater than 60°C; and performing a first separation on the first mixture to obtain purified alkaline resin.

[0005] In this embodiment of the application, at 25°C, the surface tension of the first alcohol ether solvent is less than or equal to 35 mN / m.

[0006] In the embodiments of this application, the first alcohol ether solvent includes one or more of diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethylene glycol monobutyl ether, and dipropylene glycol methyl ether.

[0007] In the embodiments of this application, the volume ratio of diethylene glycol monobutyl ether to diethylene glycol dimethyl ether in the first alcohol ether solvent is (1~2):1.

[0008] In the embodiments of this application, the volume ratio of diethylene glycol monobutyl ether to ethylene glycol monobutyl ether in the first alcohol ether solvent is (1~3):1.

[0009] In the embodiments of this application, the volume ratio of diethylene glycol monobutyl ether, ethylene glycol monobutyl ether and diethylene glycol dimethyl ether in the first alcohol ether solvent is (1~3): (0.5~3):1.

[0010] In this embodiment of the application, after the first separation, the product is further washed with a second alcohol ether solvent to obtain the purified alkaline resin through a second separation.

[0011] In this embodiment of the application, the second separation includes centrifuging or vacuum drying of the alkaline resin; the centrifugation speed is 45 rpm to 50 rpm and the time is 30 min to 45 min; the vacuum drying temperature is 60 ℃ to 85 ℃ and the time is 8 h to 24 h, and the vacuum degree is -0.09 MPa to -0.08 MPa.

[0012] In the embodiments of this application, the impurity removal rate of the purification method is greater than or equal to 90%.

[0013] Secondly, embodiments of this application provide an alkaline resin, which is obtained by purification using the purification method provided in the first aspect of this application.

[0014] Thirdly, embodiments of this application provide an anion exchange membrane, which includes the alkaline resin provided in the second aspect of this application.

[0015] In this embodiment, the swelling degree of the anion exchange membrane is 15%~25%.

[0016] Fourthly, embodiments of this application provide an application of the alkaline resin provided in the second aspect of this application or the anion exchange membrane provided in the third aspect of this application in the fields of electrolyzers, fuel cells, and flow batteries.

[0017] The purification method for alkaline resin provided in this application uses a treatment solution with high flash point, high boiling point, and low surface tension. This treatment solution has high safety, is not subject to law enforcement regulations, and can deeply remove impurities from crude alkaline resin. As a result, the amount of residual impurities in the purified alkaline resin is greatly reduced. When used in an electrochemical system, it can significantly improve the ion exchange rate, reduce the internal resistance, and enhance the operational stability of electrochemical devices. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. The specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0019] Figure 1 OH prepared in Example 4 of this application - Atomic force microscopy (AFM) images of a type anion exchange membrane; Figure 2 OH prepared as Comparative Example 1 of this application - AFM images of a type of anion exchange membrane; Figure 3 This is a comparison chart of the single-cell polarization performance of Examples 1 to 4, Example 9 and Comparative Example 1 of this application; Figure 4 This is a comparison chart of the single-cell stability of Examples 1, 9 and Comparative Example 1 of this application. Detailed Implementation

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0021] As an important functional polymer material, alkaline resins are widely used in water treatment, electrochemical energy, catalytic separation and other fields. After their synthesis, the resin micropores often contain a large number of impurities such as residual monomers, pore-forming agents and linear polymers, which seriously affect the purity of the resin and its application performance.

[0022] Currently, the industry commonly uses a precipitation-washing combined process to purify crude alkaline resins: for example, the resin is first precipitated using organic solvents such as diethyl ether and acetone, then centrifuged and washed with solvents such as ethyl acetate, and finally washed with water and dried to obtain the finished product. This traditional process has significant drawbacks: First, organic solvents such as diethyl ether and acetone are precursor chemicals for toxic substances, and their purchase, use, and storage require strict registration and supervision, which significantly increases the compliance costs and legal risks for enterprises; Second, diethyl ether, acetone, and ethyl acetate have extremely low flash points and are highly volatile, classified as Class A flammable hazardous materials. They can easily form explosive gas mixtures during centrifugation, spraying, and other processes, seriously endangering the health of operators and posing extremely high fire and explosion safety risks. Production must use high-level explosion-proof equipment and inert gas protection, resulting in high equipment investment and operating costs; In addition, these traditional solvents have high surface tension and weak penetration, making it difficult to deeply remove residual monomers, pore-forming agents, and linear polymers from the resin micropores, leading to insufficient resin purity, high membrane surface roughness, poor interfacial contact, and directly reducing ion conduction efficiency and long-term operational stability. Therefore, developing a safe, environmentally friendly, efficient, and low-consumption alkaline resin post-treatment technology has become a key issue that urgently needs to be addressed in this field.

[0023] Therefore, embodiments of this application provide a method for purifying alkaline resin, comprising the following steps: S1: The crude alkaline resin is mixed with a first alcohol ether solvent to obtain a first mixture, wherein the flash point of the first alcohol ether solvent is greater than 60°C; S2: Perform a first separation on the first mixture to obtain purified alkaline resin.

[0024] In this embodiment, a first alcohol ether solvent is used to purify the crude alkaline resin. The first alcohol ether solvent not only has a high flash point, which ensures that the purification process is free from flammability, explosion and toxicity risks, but also has low surface tension and compatibility. It can deeply remove residual impurities inside the alkaline resin, making the resin channels unobstructed and the film surface smooth, effectively improving the ion conduction efficiency and long-term stability of the resin material.

[0025] Step S1 is essentially a solvent displacement process and an impurity dissolution process. The crude alkaline resin is mixed with a first alcohol ether solvent. The first alcohol ether solvent precipitates the alkaline resin and dissolves the impurities in the alkaline resin, causing the alkaline resin to precipitate from a solution state into a solid state. At the same time, the impurities inside the alkaline resin (such as unreacted quaternizing reagents, oligomers, or by-products) are dissolved and retained in the solvent of the first mixture, thereby achieving the initial separation of impurities from the alkaline resin.

[0026] In some embodiments of this application, the crude alkaline resin can be a solid crude alkaline resin or a crude alkaline resin liquid. The crude alkaline resin liquid includes the crude alkaline resin and a solvent. The solvent may be, but is not limited to, one or more of dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), acetonitrile (ACN), and nitrobenzene. The aforementioned solvents have good miscibility with first alcohol ether solvents, which helps to induce the resin to precipitate from the crude resin liquid, rapidly transforming the uniformly dispersed solution state into solid resin precipitation, forming a solid-liquid mixed suspension system with the solvent.

[0027] In some embodiments of this application, the crude alkaline resin includes a quaternized alkaline resin, which can be obtained by quaternizing an alkaline resin polymer. The main chain structure of the alkaline resin polymer can include one or more of the following: a fluorocarbon backbone, an ether-containing backbone, a benzene ring backbone, a polyaryl ring backbone, and a chain-like backbone. In some specific embodiments of this application, the alkaline resin polymer can be, for example, but is not limited to, one or more of the following: perfluorosulfonic acid polymers, perfluoroquaternary ammonium polymers, polyphenylene ether, polyetheretherketone, polyethersulfone, polyarylpiperidine, polyarylpyridine, polystyrene, polyphenylene sulfide, polyethylene, polypropylene, and polyvinyl chloride.

[0028] In some embodiments of this application, the quaternizing agent used in the quaternization modification process may be, but is not limited to, one or more of iodomethane, bromomethane, bromoethane, bromopropane, bromobutane, bromododecane, chloromethane, chloroethane, chloropropane, benzyl chloride, benzyl bromide, dimethyl sulfate, and diethyl sulfate.

[0029] In this application, the first alcohol ether solvent refers to a class of organic compounds containing an oxyether group (-O-) and a methyl group (-CH3). The oxyether group is hydrophilic, and the methyl group is hydrophobic, which gives the first alcohol ether solvent a unique amphiphilic characteristic. This structure endows it with low surface tension. In some embodiments of this application, the molecular structure of the first alcohol ether solvent also contains a hydroxyl group. The coexistence of the hydroxyl group and the oxyether group further enhances the hydrophilicity of the first alcohol ether solvent.

[0030] In some embodiments of this application, the first alcohol ether solvent includes one or more of diethylene glycol monobutyl ether (DEGBE), diethylene glycol dimethyl ether (DEGDME), ethylene glycol monobutyl ether (EGBE), and dipropylene glycol methyl ether (DPM). The chemical structure of diethylene glycol monobutyl ether is as follows: The chemical structure of diethylene glycol dimethyl ether is: The chemical structure of ethylene glycol monobutyl ether is: The chemical structure of dipropylene glycol methyl ether is: .

[0031] In the embodiments of this application, at 25°C, the surface tension of the first alcohol ether solvent is less than or equal to 35 mN / m, for example, but not limited to, 10 mN / m, 15 mN / m, 20 mN / m, 25 mN / m, 25.1 mN / m, 26 mN / m, 27.4 mN / m, 27.8 mN / m, 28.8 mN / m, 29 mN / m, 30 mN / m, 31 mN / m, 32 mN / m, 33 mN / m, 34 mN / m, and 35 mN / m. In some embodiments of this application, the surface tension of the first alcohol ether solvent is 25 mN / m to 35 mN / m. For example, at 25°C, the surface tension of diethylene glycol monobutyl ether is 33.6 mN / m, that of diethylene glycol dimethyl ether is 29.5 mN / m, that of ethylene glycol monobutyl ether is 27.4 mN / m, and that of dipropylene glycol methyl ether is 28.8 mN / m. This low surface tension characteristic reduces the interfacial tension with the alkaline resin surface, allowing the first alcohol ether solvent to rapidly penetrate deep into the micropores along the resin channels under the action of a centrifugal force field. This dissolves and displaces impurities in "dead zones" that are difficult for traditional solvents to reach, effectively improving the impurity removal rate. Furthermore, the aforementioned reagents are miscible with water in any proportion, have a high boiling point and low volatility, and can form a homogeneous system with water in the subsequent water washing stage, carrying away dissolved impurities. This effectively avoids the solvent entrapment phenomenon commonly seen with non-water-soluble solvents. This synergistic washing mechanism of "deep penetration - full dissolution - liquid phase carry-out" significantly improves the impurity removal rate. The surface tension of the first alcohol ether solvent can be detected using a contact angle meter.

[0032] In some embodiments of this application, the flash point of the first alcohol ether solvent is greater than 60°C. The flash point is defined as the lowest temperature at which a substance and ambient air form a mixture and come into contact with a flame, resulting in a flash and immediate combustion. It reflects the evaporation tendency and thermal stability of the substance. Specifically, the flash points of diethylene glycol monobutyl ether are approximately 90°C, diethylene glycol dimethyl ether is approximately 70°C, ethylene glycol monobutyl ether is approximately 62°C, and dipropylene glycol methyl ether is approximately 75°C. Compared to traditional processing agents such as diethyl ether (flash point -45°C), acetone (flash point -20°C), and ethyl acetate (flash point -4°C), the first alcohol ether solvents provided in this application significantly reduce the risk of fire and explosion. Furthermore, they are low-toxicity or practically non-toxic reagents, posing a far lower health hazard to operators than traditional solvents such as diethyl ether and acetone. They possess the triple characteristics of being non-flammable and non-explosive, having low volatility, and low toxicity, making the production environment safer and more environmentally friendly, in line with the development concept of green chemistry.

[0033] In some embodiments of this application, the first alcohol ether solvent includes at least two of diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethylene glycol monobutyl ether, and dipropylene glycol methyl ether. The dipole moments of diethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol monobutyl ether, and dipropylene glycol methyl ether are all between 1.5 Debye and 3 Debye. The dipole moment is a physical quantity that measures the degree of separation between positive and negative charge centers in a molecule, and its unit is Debye (abbreviated as D). It is used to represent the polarity of the molecule; the larger the dipole moment, the stronger the polarity of the molecule. Specifically, the dipole moment of diethylene glycol monobutyl ether is 2D to 2.5D, the dipole moment of diethylene glycol dimethyl ether is 1.5D to 1.8D, the dipole moment of ethylene glycol monobutyl ether is approximately 2.08D, and the dipole moment of dipropylene glycol methyl ether is approximately 2D to 2.5D. When the first alcohol ether solvent contains at least two of the above-mentioned reagents of different polarities, it can simultaneously and specifically dissolve impurities of different polarities in the basic resin, thereby improving the overall solubility of impurities.

[0034] In some embodiments of this application, the boiling point of the first alcohol ether solvent is 150°C to 250°C under normal pressure, for example, but not limited to, 150°C, 160°C, 170°C, 171°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, and 250°C. This application uses first alcohol ether solvents with higher boiling points, which have lower vapor pressure and slower evaporation rates under conventional and ambient temperature operation. This is suitable for the stirring, filtration, and separation processes in purification, significantly reducing the health hazards of solvent evaporation, such as respiratory irritation to operators, and the risk of fire. Specifically, the boiling point of diethylene glycol monobutyl ether is 230°C, the boiling point of diethylene glycol dimethyl ether is 160°C, the boiling point of ethylene glycol monobutyl ether is 171°C, and the boiling point of dipropylene glycol methyl ether is 190°C.

[0035] In some embodiments of this application, at 25°C, the dielectric constant of the first alcohol ether solvent is 7~30, for example, but not limited to 7, 7.2, 7.5, 9.7, 10, 12, 13, 15, 20, 25, 30. The dielectric constant is an important parameter for measuring solvent polarity. If the dielectric constant is below 7, the solvent polarity is too weak, making it difficult to effectively dissolve impurities such as polar monomers and pore-forming agents remaining during resin synthesis. If the dielectric constant is above 30, the solvent polarity is too strong; although it can dissolve impurities, it will cause excessive swelling of the resin, damaging its pore structure and mechanical strength. Specifically, at 25°C, the dielectric constant of diethylene glycol monobutyl ether is 9.7, the dielectric constant of diethylene glycol dimethyl ether is 7.2, the dielectric constant of ethylene glycol monobutyl ether is 13, and the dielectric constant of dipropylene glycol methyl ether is 7.5.

[0036] In some embodiments of this application, the first alcohol ether solvent includes diethylene glycol monobutyl ether and diethylene glycol dimethyl ether. In this case, the volume ratio of diethylene glycol monobutyl ether to diethylene glycol dimethyl ether is (1~2):1, for example, but not limited to, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, and 2:1. The surface tension is further reduced after the diethylene glycol monobutyl ether and diethylene glycol dimethyl ether are combined, making it easier to penetrate deep into the resin micropores and displace impurities. It also controls the swelling degree of the alkaline resin within a suitable range, ensuring that the resin pores are fully opened for impurity diffusion and dissolution, without reducing the mechanical strength of the resin or causing a loose film structure due to excessive swelling.

[0037] In some embodiments of this application, the first alcohol ether solvent includes diethylene glycol monobutyl ether and ethylene glycol monobutyl ether. In this case, the volume ratio of diethylene glycol monobutyl ether to ethylene glycol monobutyl ether is (1~3):1, for example, but not limited to, 1:1, 1.2:1, 1.5:1, 1.8:1, 2:1, 2.3:1, 2.5:1, 2.7:1, and 3:1. Diethylene glycol monobutyl ether has relatively longer flexible segments and stronger resin penetration ability. Ethylene glycol monobutyl ether has a smaller molecular weight, lower surface tension, and stronger volatility, resulting in stronger dissolution and carrying capacity for small molecule impurities. Combining the two in a volume ratio of (1~3):1 has the effect of size complementarity and enhanced penetration.

[0038] In some embodiments of this application, the first alcohol ether solvent includes diethylene glycol monobutyl ether, ethylene glycol monobutyl ether, and diethylene glycol dimethyl ether. In this case, the volume ratio of diethylene glycol monobutyl ether, ethylene glycol monobutyl ether, and diethylene glycol dimethyl ether is (1~3):(0.5~3):1, for example, but not limited to 1:0.5:1, 1:2:1, 2:1:1, 3:1.5:1, and 3:3:1. This ternary complex system forms a gradient match in four dimensions: polarity, molecular size, swelling capacity, and penetration depth, achieving deep penetration and broad-spectrum impurity removal, thus greatly improving impurity removal efficiency and maintaining structural strength.

[0039] Step S2 is essentially an impurity removal and solid-liquid separation process. The first separation of the first mixture can be, but is not limited to, centrifugation, including putting the first mixture into a centrifuge. Under the action of centrifugal force, impurities are thrown out with the solvent, while alkaline resin is retained, thereby achieving impurity removal and solid-liquid separation.

[0040] In some embodiments of this application, the centrifugation process used for the first separation involves a centrifuge speed of 45 rpm to 50 rpm and a centrifugation time of 30 min to 45 min.

[0041] In other embodiments of this application, the purification method for alkaline resin includes the following steps: S1: The crude alkaline resin is mixed with a first alcohol ether solvent to obtain a first mixture, wherein the flash point of the first alcohol ether solvent is greater than 60°C; S2: The first mixture is subjected to a first separation, and the first separation product is washed with a second alcohol ether solvent. After a second separation, a purified alkaline resin is obtained.

[0042] Step S1 is the same as the aforementioned step S1, and will not be repeated here. The first separation in step S2 is the same as the first separation in the aforementioned step S2. After the first separation, the product of the first separation is washed with a second alcohol ether solvent to achieve deep purification. Finally, the solvent is removed by the second separation to obtain purified alkaline resin.

[0043] In this application, second alcohol ether solvents refer to a class of organic compounds containing an oxyether group (-O-) and a methyl group (-CH3). The oxyether group is hydrophilic, and the methyl group is hydrophobic. These two groups give second alcohol ether solvents a unique amphiphilic characteristic, and this structure endows them with low surface tension. In some embodiments of this application, the molecular structure of the second alcohol ether solvent also contains a hydroxyl group. The coexistence of the hydroxyl group and the oxyether group further enhances the hydrophilicity of the second alcohol ether solvent.

[0044] In some embodiments of this application, the second alcohol ether solvent includes one or more of diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethylene glycol monobutyl ether, and dipropylene glycol methyl ether. In some specific embodiments of this application, the second alcohol ether solvent and the first alcohol ether solvent may be the same or different. Here, "same" means that the types and proportions of components in the second alcohol ether solvent and the first alcohol ether solvent are the same, and "different" means that the types or proportions of components in the second alcohol ether solvent and the first alcohol ether solvent are different.

[0045] In some embodiments of this application, the second alcohol ether solvent differs from the first alcohol ether solvent. When they differ, the differences in properties between the different solvents can achieve complementary washing effects. In some specific embodiments of this application, the first alcohol ether solvent includes diethylene glycol monobutyl ether, which utilizes its moderate swelling properties to achieve initial impurity dissolution. The second alcohol ether solvent includes ethylene glycol monobutyl ether, which utilizes its lower surface tension to enhance the displacement ability of impurities deep in micropores. In other specific embodiments of this application, the first alcohol ether solvent includes diethylene glycol monobutyl ether, and the second alcohol ether solvent includes diethylene glycol dimethyl ether, which utilizes its lower polarity to dissolve non-polar impurities remaining in the resin. In still other specific embodiments of this application, the first alcohol ether solvent includes diethylene glycol monobutyl ether, and the second alcohol ether solvent includes both ethylene glycol monobutyl ether and diethylene glycol dimethyl ether, simultaneously utilizing the aforementioned properties of both to synergistically improve washing efficiency.

[0046] In some embodiments of this application, the washing method may be, but is not limited to, spray washing, soaking washing, stirring washing, and shaking washing, and the number of washing cycles may be 1 to 3.

[0047] In some embodiments of this application, the second separation includes centrifuging or vacuum drying the washed alkaline resin. In some specific embodiments, the centrifugation speed is 45 rpm to 50 rpm, for example, but not limited to 50 rpm; the centrifugation time is 30 min to 45 min, for example, but not limited to 40 min. In some embodiments of this application, the vacuum drying temperature is 60℃ to 80℃, for example, but not limited to 60℃, 65℃, 70℃, 75℃, or 80℃; the vacuum drying time is 8 h to 24 h, for example, but not limited to 8 h, 10 h, 15 h, 20 h, or 24 h; the vacuum degree of vacuum drying is -0.09 MPa to -0.08 MPa. The above-mentioned second separation process aims to effectively remove the residual treatment liquid from the surface and interior of the alkaline resin, ultimately obtaining high-purity alkaline resin free of impurities and solvent residue, i.e., purified alkaline resin.

[0048] In some embodiments of this application, the impurity removal rate of the aforementioned purification method is greater than or equal to 90%, for example, but not limited to 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, and 100%. The impurity removal rate in this application is calculated using the formula [(M1-M2) / M1] × 100%, where M1 is the impurity content in the crude alkaline resin after purification with pure water, and M2 refers to the impurity content in the purified alkaline resin. This application can use high-performance liquid chromatography-mass spectrometry (HPLC-MS) to detect the impurity content in the alkaline resin.

[0049] The purification method provided in this application completely eliminates the reliance on easily toxic, flammable, and explosive solvents such as diethyl ether and acetone in traditional processes. It develops a compliant, safe, and efficient alkaline resin purification technology. The purified alkaline resin obtained in this way can effectively reduce tank pressure and improve long-term operational stability when applied to electrochemical devices.

[0050] This application provides an alkaline resin, which is purified by the purification method provided in any of the foregoing embodiments of this application. The alkaline resin has low impurity content, unobstructed pore structure, and good film-forming properties.

[0051] This application provides an anion exchange membrane comprising purified basic resin obtained by the purification method provided in any of the foregoing embodiments of this application. The anion exchange membrane has low surface roughness and unobstructed ion transport pathway.

[0052] In some embodiments of this application, the swelling rate of the anion exchange membrane is 15%~25%, for example, but not limited to, 15%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, and 25%. In this application, the swelling rate of the anion exchange membrane is positively correlated with the swelling rate of the basic resin during purification. A swelling rate of 15%~25% reflects that the first alcohol ether solvent used in this application for purifying the crude basic resin can control the swelling rate of the basic resin within a suitable range, ensuring a suitable pore structure for effective impurity removal while avoiding excessive resin swelling that could lead to pore collapse and affect structural stability. In some specific embodiments of this application, the swelling rate of the anion exchange membrane is 17%~22%. This application uses GB / T 20042.3-2022 Proton Exchange Membrane Fuel Cells - Part 3: Proton Exchange Membrane Test Methods - 10 Swelling Rate Test Method to detect the swelling rate of the anion exchange membrane.

[0053] This application provides a membrane electrode, which includes an anion exchange membrane electrode, comprising a cathode, an anode, and the aforementioned anion exchange membrane, wherein the anion exchange membrane is disposed between the cathode and the anode.

[0054] This application provides an electrolyzer including the membrane electrode described above. This electrolyzer can be used for hydrogen production via water electrolysis, exhibiting high hydrogen production efficiency, low energy consumption, and a long service life. In some embodiments of this application, the electrolyzer includes an anion exchange membrane electrolyzer.

[0055] This application provides a fuel cell including the membrane electrode assembly (MEA) described above. This fuel cell exhibits a fast redox reaction rate, low energy consumption, and long service life under alkaline operating conditions. In some embodiments of this application, the fuel cell includes anion exchange membrane fuel cell.

[0056] This application provides a flow battery that includes the anion exchange membrane described above. This flow battery combines low membrane resistance with high voltage efficiency and energy efficiency. In some embodiments of this application, the flow battery includes an alkaline zinc-based flow battery, an aqueous organic flow battery, and an alkaline porous membrane flow battery.

[0057] This application also provides an application of purified alkaline resin obtained by the purification method provided in any of the foregoing embodiments in the fields of electrolyzers, fuel cells, or flow batteries. In some embodiments of this application, the purified alkaline resin can be used in the field of hydrogen production through water electrolysis, specifically in the preparation of anion exchange membrane electrolyzers to generate hydrogen and oxygen through water electrolysis. In some embodiments of this application, the purified alkaline resin can be applied in the field of fuel cells, specifically in the preparation of anion exchange membrane fuel cells, etc. In some embodiments of this application, the purified alkaline resin can be applied in the field of flow batteries, specifically in the preparation of alkaline zinc-based flow batteries, aqueous organic flow batteries, alkaline porous membrane flow batteries, etc. In some embodiments of this application, the purified alkaline resin can be used in the field of water purification, for example, in the fabrication of anion exchange membranes, utilizing the selective permeation characteristics of anion exchange membranes to ions in the electrolyte to achieve separation techniques for solution desalination or concentration.

[0058] The effects of the technical solution of this application will be further illustrated below with several specific examples. The raw materials used in the embodiments of this application are all commercially available products.

[0059] Example 1 1) Treatment with first alcohol ether solvent: Dissolve 150g of polyarylpiperidine resin in 750mL of DMSO, add 100g of iodomethane as a quaternization reagent, stir at 80℃ for 15h to obtain crude quaternized basic resin solution, then add 2L of diethylene glycol monobutyl ether (first alcohol ether solvent DEGBE) to the above crude solution, the resin precipitates out in solid form to obtain the first mixture containing solid basic resin; 2) First separation: The first mixture was put into a centrifuge, the centrifuge speed was set to 50 rpm, the centrifugation time was 30 min, the solvent was removed, and the purified alkaline resin was obtained.

[0060] Example 2 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) is diethylene glycol dimethyl ether (DEGDME), while the other raw material ratios, purification steps and operating parameters are the same as in Example 1.

[0061] Example 3 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) is ethylene glycol monobutyl ether (EGBE), while the other raw material ratios, purification steps and operating parameters are the same as in Example 1.

[0062] Example 4 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) is dipropylene glycol methyl ether (DPM), while the other raw material ratios, purification steps and operating parameters are the same as in Example 1.

[0063] Example 5 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) consists of diethylene glycol monobutyl ether (DEGBE) and diethylene glycol dimethyl ether (DEGDME) in a volume ratio of 1:1. The other raw material ratios, purification steps and operating parameters are the same as in Example 1.

[0064] Example 6 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) consists of diethylene glycol monobutyl ether (DEGBE) and diethylene glycol dimethyl ether (DEGDME) in a volume ratio of 1.5:1. The other raw material ratios, purification steps and operating parameters are the same as in Example 1.

[0065] Example 7 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) is composed of diethylene glycol monobutyl ether (DEGBE) and ethylene glycol monobutyl ether (EGBE) in a volume ratio of 2:1. The other raw material ratios, purification steps and operating parameters are the same as in Example 1.

[0066] Example 8 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) is composed of diethylene glycol monobutyl ether (DEGBE), ethylene glycol monobutyl ether (EGBE), and diethylene glycol dimethyl ether (DEGDME) in a volume ratio of 1:0.5:1. The remaining raw material ratios, purification steps, and operating parameters are the same as in Example 1.

[0067] Example 9 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) is composed of diethylene glycol monobutyl ether (DEGBE), ethylene glycol monobutyl ether (EGBE) and diethylene glycol dimethyl ether (DEGDME) in a volume ratio of 2:1:1. The other raw material ratios, purification steps and operating parameters are the same as in Example 1.

[0068] Example 10 The only difference from Example 1 is that the first alcohol ether solvent used in step 1) is composed of diethylene glycol monobutyl ether (DEGBE), ethylene glycol monobutyl ether (EGBE) and diethylene glycol dimethyl ether (DEGDME) in a volume ratio of 3:3:1. The other raw material ratios, purification steps and operating parameters are the same as in Example 1.

[0069] Example 11 1) Treatment with a first alcohol ether solvent: Same as in Example 1, to obtain a first mixture containing a solid basic resin; 2) First separation: Same as in Example 1, obtaining an alkaline resin filter cake; 3) Washing and secondary separation: The alkaline resin filter cake was washed and separated by spraying three times with ethylene glycol monobutyl ether (EGBE, a second alcohol ether solvent). The filter cake was then put back into a centrifuge at a speed of 50 rpm for 40 min to obtain purified alkaline resin.

[0070] Example 12 The only difference from Example 8 is that the second alcohol ether solvent used in step 3) is diethylene glycol dimethyl ether (DEGDME), while the other raw material ratios, purification steps and operating parameters are the same as in Example 8.

[0071] Comparative Example 1 150g of polyarylpiperidine resin was dissolved in 750mL of DMSO. 100g of iodomethane was added as a quaternizing agent, and the mixture was stirred at 80℃ for 15h to obtain a crude quaternized basic resin solution. Then, 2L of ethyl acetate was added to the crude solution, causing the resin to precipitate as a solid, resulting in a first mixture containing solid basic resin. This first mixture was centrifuged at 50rpm for 30min to remove the solvent, yielding a basic resin filter cake. The filter cake was then washed three times with ethyl acetate and subjected to solid-liquid separation. It was then centrifuged again at 50rpm for 40min to obtain purified basic resin.

[0072] Comparative Example 2 150g of polyarylpiperidine resin was dissolved in 750mL of DMSO. 100g of iodomethane was added as a quaternizing agent, and the mixture was stirred at 80℃ for 15h to obtain a crude quaternized basic resin solution. A mixed solvent of 2L of diethyl ether and ethylene glycol (volume ratio 1:1) was added to the crude solution, causing the resin to precipitate as a solid, resulting in a first mixture containing solid basic resin. This first mixture was centrifuged at 50rpm for 30min to remove the solvent, yielding a basic resin filter cake. The filter cake was then washed three times with ethyl acetate for solid-liquid separation, and then centrifuged again at 50rpm for 40min to obtain purified basic resin.

[0073] Comparative Example 3 150g of polyarylpiperidine resin was dissolved in 750mL of DMSO. 100g of iodomethane was added as a quaternizing agent. The mixture was stirred at 80℃ for 15h to obtain a crude quaternized basic resin solution. After the reaction was completed, 2mL of pure water was added to the crude solution. The resin precipitated out as a solid, resulting in a first mixture containing solid basic resin. The first mixture was then placed in a centrifuge. The centrifuge speed was set to 50rpm and the centrifugation time was 30min to remove the solvent and obtain a basic resin filter cake.

[0074] (I) Surface tension test, swelling rate test and impurity removal rate test: (1) Surface tension test: The surface tension of the first alcohol ether solvent used in Examples 1 to 12 and Comparative Examples 1 to 3 was tested using a contact angle tester; (2) Swelling rate test: ① Preparation of anion exchange membrane: Weigh 2g of the final alkaline resin products from Examples 1-12 and Comparative Examples 1-3, respectively, and add them to 10mL of dimethyl sulfoxide. Stir at 80℃ until completely dissolved and homogeneous to obtain a resin slurry. Cut a PET base membrane of appropriate size and fix it on a horizontal platform. Using an SZQ type preparation apparatus, evenly coat 10mL of the resin slurry onto the apparatus and sweep it at a uniform speed of 150mm / s to form a wet film with a thickness of 230μm. Place the coated wet film in a 70℃ drying oven for 10 hours to allow the solvent to evaporate completely, obtaining a solid resin membrane. Finally, peel the dried membrane from the base membrane and soak it in a 1mol / L KOH solution (60℃) for 24 hours to convert it into OH-. - Type A anion exchange membrane, washed until neutral, is ready for use.

[0075] ② The swelling ratio of the anion exchange membrane was tested according to GB / T 20042.3-2022-Proton Exchange Membrane Fuel Cells Part 3-Proton Exchange Membrane Test Methods-10 Swelling Ratio Test Method. The specific steps are as follows: 1) Sample preparation: The above OH... - The anion exchange membrane is cut into rectangular sample membranes of 40mm×20mm. The rectangular sample membranes are required to be flat, without wrinkles, defects and damage. Each group of tests shall have no less than 3 samples.

[0076] 2) Initial Dimension Measurement: The sample film was conditioned for 4 hours in a constant temperature and humidity environment of 23℃±2℃ and 50%±5% relative humidity. After conditioning, the initial length (L) of the sample was measured using calipers with an accuracy of not less than 0.02 mm. dry ) and initial width (W dry ).

[0077] 3) Alkali immersion treatment: After measuring the initial dimensions, completely immerse the sample membrane in a 1M KOH solution at 80℃±1℃ for 30 minutes. Remove the rectangular sample membrane, replace with fresh alkali solution, and repeat the immersion operation 3 times.

[0078] 4) Water washing treatment: After soaking in alkaline solution, the sample is repeatedly rinsed with deionized water until the rinsing solution is neutral to remove the alkaline solution remaining on the surface and inside the sample membrane.

[0079] 5) Water bath immersion: Immerse the washed sample membrane completely in a constant temperature water bath at 80℃±1℃ for 2 hours to allow the sample membrane to fully absorb water and become saturated.

[0080] 6) Dimension measurement after saturation: Remove the sample membrane from the water bath, gently absorb excess water from the surface with filter paper, and quickly measure the length of the sample membrane (L) again. wet ) and width (W) wet ).

[0081] 7) Swelling rate calculation: Calculate the transverse swelling rate and longitudinal swelling rate according to the following formula. The swelling rate is the average of the transverse swelling rate and longitudinal swelling rate. Take the average of the swelling rates of 3 parallel sample films as the final swelling rate data and record it in Table 1.

[0082] Lateral swelling ratio = [(L wet - L dry ) / L dry ]×100% Longitudinal swelling ratio = [(W wet -W dry ) / W dry ]×100% (3) The specific detection method for impurity removal rate is as follows: ① Sample Extraction: Weigh 1.0 g (accurate to 0.1 mg) of the final alkaline resin product from Examples 1-12 and Comparative Examples 1-3, respectively, and place it in a Soxhlet extractor. Add 50 mL of methanol (or dichloromethane) as the extraction solvent. Reflux at 80 °C for 8 h. Transfer the extract to a 100 mL volumetric flask, dilute to the mark with the extraction solvent, and mix well. Filter 1 mL of the extract through a 0.22 μm filter membrane for HPLC-MS analysis. ②HPLC-MS detection parameters: HPLC used a C18 reversed-phase column (4.6×150mm, 5μm), column temperature 30℃, mobile phase 0.1% formic acid aqueous solution (A) and methanol (B), flow rate 0.8mL / min, injection volume 10μL, detection wavelength 254nm, gradient elution program: 0-5min, 10%B→50%B; 5-15min, 50%B→90%B; 15-20min, 90%B; 20-22min, 90%B→10%B; 22-25min, 10%B. MS used an electrospray ionization source (ESI), positive ion mode, scan range m / z 50-1000; ③ Quantitative Calculation: Prepare standard solutions of impurities (styrene, divinylbenzene, toluene, etc.) with a concentration range of 0.1 μg / mL to 100 μg / mL, and plot a standard curve. Substitute the sample peak areas into the standard curve to calculate the concentration of each impurity in the extract. Calculate the content of each impurity in the resin using the formula Ci = ci × V / m, where Ci is the content of a certain impurity in the resin (μg / g), ci is the concentration of that impurity in the extract (μg / mL), and V is the final volume of the extract (mL). m Let M2 be the mass (g) of the resin sample, and M2 be the total impurity content.

[0083] ④ Calculation of impurity removal rate: The impurity removal rate is calculated using the formula [(M1-M2) / M1] ×100%, where M1 is the impurity content in the alkaline resin filter cake in Comparative Example 3 (unit: μg / g resin), and M2 is the total impurity content of the purified alkaline resins obtained in Examples 1-12 and Comparative Examples 1-2 (unit: μg / g resin).

[0084] The above test results are shown in Table 1: Table 1

[0085] As shown in Table 1, compared to Comparative Examples 1-3, the first alcohol ether solvents used in Examples 1-12 not only have lower surface tension but also allow the alkaline resin to have a suitable swelling rate, ultimately resulting in a higher impurity removal rate. In reality, various factors such as the surface tension, solubility, swelling capacity, amphiphilicity, and volatility of the purification solvent all affect the purification and impurity removal effect. Although the purification solvents used in Comparative Examples 1 and 2 have lower surface tensions than the first alcohol ether solvents used in Examples 1-12, their deficiencies in other dimensions, such as swelling capacity and displacement capacity, lead to a lower overall impurity removal rate. Comparative Example 3 serves as a control group in this application. Based on the impurity content (M1) of the alkaline resin filter cake in Comparative Example 3, the removal effect of pure water on impurities in the alkaline resin was calculated to be extremely low.

[0086] Compared to Examples 1-4, which used a single-component first alcohol ether solvent, Examples 5-10 combined multiple first alcohol ether solvents, which significantly improved the purification and impurity removal effect. Examples 11 and 12, based on the examples, used different first alcohol ether solvents for an additional purification wash. Utilizing the differences in the properties of different solvents, a complementary washing effect was achieved, enabling the thorough removal of impurities not captured in Example 1, further improving the impurity removal rate.

[0087] Figure 1 OH prepared in Example 4 of this application - Atomic force microscopy (AFM) images of a type anion exchange membrane. Figure 2 OH prepared as Comparative Example 1 of this application - AFM images of type-3 anion exchange membranes, compared Figure 1 and Figure 2 As can be seen, the membrane material of Example 4, purified by dipropylene glycol methyl ether, has a continuous hydrophilic and hydrophobic phase and a lower surface roughness, while the membrane material of Comparative Example 1, purified by ethyl acetate, has a poorer continuity and a higher roughness. This difference in morphology will result in the anion exchange membrane of Example 4 having a lower membrane resistance and a higher ion selectivity, and its electrochemical performance is significantly better than that of Comparative Example 1.

[0088] (II) Single-pool performance testing The OH prepared in the above embodiments and comparative examples - The anion exchange membrane was cut into 10cm × 10cm pieces. Anode catalyst layer slurry (NiFe-LDH catalyst and ion-conducting resin dispersed in isopropanol) and cathode catalyst layer slurry (Pt / Ru / C catalyst and ion-conducting resin dispersed in isopropanol) were prepared separately and uniformly coated on both sides of the anion exchange membrane using a spraying method. The anode catalyst loading was 1 mg / cm³. 2 Cathode catalyst loading 1 mg / cm 2 After being vacuum dried at 60℃, it is assembled with the anode gas diffusion layer (nickel foam and the cathode gas diffusion layer (carbon paper)) to form a film electrode. Then, it is cut to the required size and placed in an effective area of ​​5cm². 2 In the single-cell fixture, platinum-plated titanium plates are used as electrodes, a serpentine flow field design is employed, and PTFE sealing is implemented. During testing, a 1 mol / L KOH solution was used as the electrolyte, the flow rate was 100 mL / min, and the temperature was 70℃. After equilibration for 30 min, polarization curves were measured using constant current mode. Steady-state voltages at different current densities were recorded, and long-term stability tests (1 A / cm²) were also conducted. 2 (After running for 473 hours) the cell pressure decay rate was calculated to evaluate the single-cell performance of the anion exchange membrane.

[0089] Figure 3 This is a comparison chart of the single-cell polarization performance of Examples 1-4, Example 9, and Comparative Example 1 of this application. Figure 3 As can be seen, the current density (horizontal axis) is 1 A / cm². 2 At that time, the cell pressure (vertical axis) corresponding to Example 1 was 1.651V, Example 2 was 1.663V, Example 3 was 1.653V, Example 4 was 1.677V, Example 9 was 1.647V, and Comparative Example 1 was 1.757V. Compared with Comparative Example 1, Examples 1 to 4 and Example 9 showed lower operating cell pressures, which can achieve lower electrochemical energy consumption. This advantage stems from the following: Firstly, during the purification and impurity removal stage, the ether bonds and hydroxyl groups in the molecular structures of DEGBE, DEGDME, EGBE, and DPM cause them to spontaneously adsorb at the hydrophilic and hydrophobic phase interfaces, guiding the resin molecules to initially arrange in an orderly manner. Furthermore, their low surface tension allows this regulatory effect to penetrate deep into the resin micropores. During the drying stage, the suitable volatility of the first alcohol ether solvent provides sufficient relaxation time for the polymer segments, allowing the hydrophilic and hydrophobic segments to fully self-assemble according to the thermodynamic minimum energy state, ultimately forming continuous, interconnected hydrophilic ion channels and a stable hydrophobic framework. Even after the solvent has been completely removed from the final purified basic resin, this ordered structure "domesticated" by the first alcohol ether solvent is retained, significantly reducing membrane resistance and improving ion conduction efficiency. Secondly, the ether bonds and hydroxyl groups in the alcohol ether reagent molecules endow the membrane surface with amphiphilicity. Combined with the low surface roughness characteristics confirmed by the aforementioned AFM images, this allows for good contact between the membrane and the electrode interface, reducing interfacial contact resistance. Thirdly, based on the synergistic washing mechanism of "deep penetration-full dissolution-liquid phase carry-out," the amount of residual impurities inside the membrane is significantly reduced, eliminating the additional overpotential caused by impurity interference. These synergistic effects collectively contribute to a significant decrease in single-cell voltage (approximately 80 mV lower than Comparative Example 1), resulting in significant energy savings and superior long-term operational stability.

[0090] Figure 4 This is a comparison chart of single-cell stability of Embodiments 1, 9, and Comparative Example 1 of this application, wherein the aforementioned... Figure 3 The horizontal axis is 1A / cm 2 The initial cell pressure is the cell pressure at the specified time. The final cell pressure is the cell pressure after 473 hours of operation in a single cell. The cell pressure decay rate is calculated according to "cell pressure decay rate = (final cell pressure - initial cell pressure) / time". The cell pressure decay rate refers to the rate at which the cell pressure of a single electrolytic cell increases over time under constant operating conditions. A higher cell pressure decay rate indicates a faster aging rate of the single cell. Figure 4It can be seen that: the initial tank pressure of Example 1 was 1.651V, the final tank pressure was 1.8356V, and the tank pressure decay rate was 0.390mV / h; the initial tank pressure of Example 9 was 1.647V, the final tank pressure was 1.8042V, and the tank pressure decay rate was 0.332mV / h; the initial tank pressure of Comparative Example 1 was 1.757V, the final tank pressure was 1.9594V, and the tank pressure decay rate was 0.428mV / h. It is evident that compared to Comparative Example 1, Examples 1 and 9 have lower single-tank tank pressure decay rates and higher stability during long-term operation. This advantage stems from: Firstly, although the purified alkaline resin ultimately contains no residual first alcohol ether solvent, it plays a "process regulation" role on the resin polymer segments during purification. Firstly, the first alcohol ether solvent, acting as a molecular-level lubricant, penetrates between polymer segments, shielding interaction forces, promoting the unwinding of physical entanglements, and providing conditions for segment rearrangement. Secondly, the amphiphilic molecular structure of the first alcohol ether solvent and the solvent itself act as a temporary template, guiding the pre-arrangement of hydrophilic and hydrophobic segments to form an ordered micelle precursor. Finally, suitable volatility ensures uniform volume shrinkage of the basic resin during drying, avoiding the "skin effect" and residual internal stress caused by rapid evaporation. Based on these temporary guiding and regulating effects, the basic resin skeleton after solvent removal retains a dense, uniform, and low-stress segment stacking structure, thus enabling the membrane to exhibit excellent resistance to phase separation and structural degradation during long-term operation. Secondly, based on the synergistic washing mechanism of "deep penetration-full dissolution-liquid phase carry-out," the amount of residual impurities inside the membrane material is extremely low, eliminating "contamination sources" that catalyze membrane degradation and block ion channels, thus slowing down the performance degradation process. Thirdly, low surface roughness and amphiphilic surface characteristics ensure a stable membrane-electrode interface contact state and resist contaminant adsorption. These synergistic effects collectively contribute to a significant reduction in single-cell voltage decay rate, providing reliable material assurance for the long-term stable operation of electrochemical devices.

[0091] In summary, the embodiments of this application, by selecting specific first ether reagents to purify crude alkaline resin, can deeply remove impurities from the crude alkaline resin. As a result, the amount of residual impurities in the purified alkaline resin is greatly reduced. When used in an electrochemical system, it can significantly improve the ion exchange rate, reduce the internal resistance, and enhance the operational stability of the electrochemical device.

[0092] The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that implementing all or part of the processes of the above embodiments and making equivalent changes in accordance with the claims of this application still fall within the scope of this application.

Claims

1. A method for purifying an alkaline resin, characterized in that, Includes the following steps: The crude alkaline resin is mixed with a first alcohol ether solvent to obtain a first mixture, wherein the flash point of the first alcohol ether solvent is greater than 60°C. The first mixture was subjected to a first separation to obtain purified alkaline resin.

2. The purification method for the alkaline resin as described in claim 1, characterized in that, At 25°C, the surface tension of the first alcohol ether solvent is less than or equal to 35 mN / m.

3. The purification method for the alkaline resin as described in claim 1 or 2, characterized in that, The first alcohol ether solvent includes one or more of diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethylene glycol monobutyl ether, and dipropylene glycol methyl ether.

4. The purification method for the alkaline resin according to any one of claims 1 to 3, characterized in that, In the first alcohol ether solvent, the volume ratio of diethylene glycol monobutyl ether to diethylene glycol dimethyl ether is (1~2):1; and / or, the volume ratio of diethylene glycol monobutyl ether to ethylene glycol monobutyl ether is (1~3):1; and / or, the volume ratio of diethylene glycol monobutyl ether, ethylene glycol monobutyl ether and diethylene glycol dimethyl ether is (1~3): (0.5~3):

1.

5. The purification method for the alkaline resin according to any one of claims 1 to 4, characterized in that, The process further includes: washing the first separation product with a second alcohol ether solvent, and obtaining the purified alkaline resin through a second separation.

6. The purification method for the alkaline resin according to any one of claims 1 to 5, characterized in that, The second separation includes centrifuging or vacuum drying the washed alkaline resin; the centrifugation speed is 45 rpm to 50 rpm and the time is 30 min to 45 min; the vacuum drying temperature is 60℃ to 85℃ and the time is 8 h to 24 h, and the vacuum degree is -0.09 MPa to -0.08 MPa.

7. The purification method for the basic resin according to any one of claims 1 to 6, characterized in that, The impurity removal rate of the purification method is greater than or equal to 90%.

8. An alkaline resin, characterized in that, The alkaline resin is obtained by purification using the purification method described in any one of claims 1 to 7.

9. An anion exchange membrane, characterized in that, Includes the alkaline resin as described in claim 8.

10. The anion exchange membrane as described in claim 9, characterized in that, The swelling degree of the anion exchange membrane is 15%~25%.

11. The application of an alkaline resin as described in claim 8 or an anion exchange membrane as described in claim 9 or 10 in the fields of electrolyzers, fuel cells or flow batteries.

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