Ultrahigh-water-permeability polyester reverse osmosis membrane based on artificial water channel and preparation method of ultrahigh-water-permeability polyester reverse osmosis membrane
By using OH-ExR4, a polyhydroxyl-containing artificial water channel, as an aqueous phase monomer in the reverse osmosis membrane, an ultra-high water permeability polyester reverse osmosis membrane was prepared, which solved the problem of low water permeability of existing reverse osmosis membranes and achieved efficient water production and water reuse.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-04
- Publication Date
- 2026-04-07
AI Technical Summary
The existing reverse osmosis membranes have low water permeability, resulting in high water production efficiency and energy consumption. Existing technologies have failed to fully utilize their excellent water permeability after embedding artificial water channels.
Polyester reverse osmosis membranes were prepared by using OH-ExR4, an artificial water channel with multiple hydroxyl groups, as an aqueous monomer for interfacial polymerization. The OH-ExR4 pores were used as the main water passage, and an ultra-high water permeability membrane was formed through an acylation reaction.
It significantly improves the water permeability and water production efficiency of the membrane, reduces operating costs and energy consumption, and is easy to scale up for production.
Smart Images
Figure CN121797121A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of membrane separation technology, specifically to an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels and its preparation method. Background Technology
[0002] Reverse osmosis membrane separation, as a highly efficient membrane separation technology, plays a leading role in water pollution control, alleviating water shortages, and reclaimed water recycling, and is widely used in fields such as advanced wastewater treatment and seawater desalination. However, existing reverse osmosis membranes primarily use polyamide as the retaining layer. Due to the high resistance of polyamide to water molecule transport, commercial reverse osmosis membranes have low water permeability, severely limiting water production efficiency and increasing energy consumption for water reuse. Therefore, how to further improve the water permeability of reverse osmosis membranes to ensure their water production and reuse efficiency, thereby reducing operating costs and energy consumption, is a research hotspot and challenge in the field of membrane-based wastewater treatment and reuse.
[0003] The research team previously discovered that embedding artificial water channels in polyamide reverse osmosis membranes can improve membrane water permeability by acting as the dominant mass transfer channels. However, embedding artificial water channels in the polyamide layer failed to fully utilize their excellent water permeability characteristics, resulting in a limited increase in membrane water permeability. Theoretically, artificial water channels can achieve a water permeability of 10⁶ to 10¹⁰ per second. Therefore, if artificial water channels could be used as reactive monomers and their packing density in the filtration layer significantly increased, it would help in the preparation of ultra-high water permeability reverse osmosis membranes that break through the current upper limit. Therefore, the present invention proposes to use artificial water channels as aqueous monomers for interfacial polymerization, resulting in reverse osmosis membrane pores dominated by artificial water channel channels. This induces chain transport of water molecules, fully utilizing the excellent water permeability characteristics of the water channels and endowing the membrane with ultra-high water permeability.
[0004] This invention synthesizes a polyhydroxy artificial water channel OH-ExR4 and uses it as an aqueous monomer in the interfacial polymerization process. Based on the acylation reaction, a polyester reverse osmosis membrane with OH-ExR4 channels as the main membrane pores is prepared, which significantly improves water permeability. Summary of the Invention
[0005] To address the aforementioned technical problems, this invention provides an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels and its preparation method. This invention utilizes the pores of OH-ExR4 in the polyester reverse osmosis membrane as the main water passage pathway, inducing chain transport of water molecules and endowing the membrane with ultra-high water permeability.
[0006] The first objective of this invention is to provide a method for preparing an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels, comprising the following steps: A precursor, fully methoxylated phenyl extended calix [4] resorcinol aromatic hydrocarbon Me-ExR4, is provided; The fully hydroxylated phenyl extended calix [4] resorcinol OH-ExR4 was prepared by demethylation reaction; Using OH-ExR4 as an aqueous monomer for interfacial polymerization, an aqueous solution containing OH-ExR4 was prepared. The aqueous solution containing OH-ExR4 was used to wet the surface of the base membrane, and then a hexane solution of trimesoyl chloride was applied to the surface of the base membrane to induce an OH-ExR4-mediated acylation reaction, thereby obtaining the ultra-high water permeability polyester reverse osmosis membrane.
[0007] In a specific embodiment of the present invention, the fully methoxylated phenyl extended calix [4] resorcinol aromatic hydrocarbon Me-ExR4 is prepared by the following method: S1. Add 1,3-dimethoxybenzene and AlCl3 to a 1,4-bis(chloromethyl)benzene solution to obtain a first mixed solution; stir the reaction under an inert atmosphere; after the reaction is completed, add a quencher to quench the reaction to obtain 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene; S2. Dissolve the obtained 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene in an organic solvent to obtain a second mixed solution. Add paraformaldehyde to obtain a third mixed solution. Stir and mix under an inert atmosphere, add trifluoroacetic acid to obtain a fourth mixed solution, and continue the reaction for 30-60 min. After the reaction is completed, add a quencher to quench the reaction to obtain Me-ExR4.
[0008] In a specific embodiment of the present invention, in step S1, the inert gas in the inert atmosphere includes nitrogen and / or argon, the stirring reaction time is 5 to 30 minutes, and the temperature is room temperature; the quenching agent is water.
[0009] In this invention, 1,3-dimethoxybenzene is used as an electron-rich aromatic nucleophile and a protecting equivalent of the phenolic hydroxyl group, providing high reactivity and good regioselectivity. AlCl3 is used as a strong Lewis acid to activate benzyl chloride to generate an electrophilic center, thus promoting the efficient conduction of the Friedel-Crafts alkylation reaction.
[0010] In a specific embodiment of the present invention, in step S1, the concentration of 1,3-dimethoxybenzene in the first mixed solution is 30~60 g / L, and the concentration of AlCl3 is 30~50 g / L; The concentration of the 1,4-bis(chloromethyl)benzene solution is 5~20 g / L.
[0011] In a specific embodiment of the present invention, in step S2, the concentration of 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene in the second mixed solution is 1~5 g / L; The concentration of paraformaldehyde in the third mixed solution is 0.2~0.8 g / L; the present invention utilizes paraformaldehyde as a slow-release source of formaldehyde under acidic conditions to provide methylene (–CH2–) linkage units, and promotes the macrocyclization construction of aromatic units through Friedel-Crafts type condensation reaction. The concentration of trifluoroacetic acid in the fourth mixed solution is 1~4 g / L. This invention utilizes trifluoroacetic acid as a strong and mild Brønsted acid to catalyze the depolymerization of paraformaldehyde and generate an active methylene electrophilic intermediate, thereby driving the aromatic unit to undergo Friedel-Crafts-type condensation, achieving efficient construction of the ExR4 macrocyclic skeleton, while effectively suppressing disordered polymerization side reactions.
[0012] The organic solvent includes one or more of dichloromethane, 1,2-dichloroethane, and chloroform; The mixing time is 5-30 minutes, and the temperature is room temperature. The quenching agent is a sodium hydroxide solution with a concentration of 0.5~2 M.
[0013] In a specific embodiment of the present invention, the conditions for the demethylation reaction are as follows: the Me-ExR4 solution is cooled in an ice bath for 5-20 min, and BBr3 is added; the reaction is carried out under an inert atmosphere at 25-40°C with stirring for 8-24 h. The present invention utilizes BBr3 as a strong Lewis acid to selectively catalyze the demethylation (deprotection) reaction of aromatic methyl ethers, quantitatively converting -OCH3 to phenolic hydroxyl groups -OH.
[0014] In a specific embodiment of the present invention, the concentration of the Me-ExR4 solution is 5~10 g / L, and the concentration of BBr3 is 15~30 g / L.
[0015] In a specific embodiment of the present invention, the concentration of OH-ExR4 in the aqueous solution containing OH-ExR4 is 5~30 g / L; The aqueous solution containing OH-ExR4 also includes NaOH at a concentration of 1.25–7.5 g / L. This invention utilizes NaOH to promote the reaction between the OH-ExR4 solvent and the interfacial polymerization.
[0016] In a specific embodiment of the present invention, the base film is selected from polysulfone film, polyethersulfone film or polyvinylidene fluoride film; The acylation reaction takes 1-20 min at a temperature of 20-30℃. The concentration of the hexane solution of pyromellitic methyl chloride is 0.1~0.5 wt / v.
[0017] A second objective of this invention is to provide an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels, prepared by the aforementioned method. The pores of OH-ExR4 in the polyester reverse osmosis membrane serve as the primary water passage pathway, inducing chain transport of water molecules and imparting ultra-high water permeability to the membrane.
[0018] The beneficial effects of this invention are: (1) The polyester reverse osmosis membrane based on OH-ExR4 significantly increases the loading of artificial water channels in the membrane. With OH-ExR4 channels as the main water passage, it fully leverages the rapid water transport advantage of artificial water channels, induces water molecule chain transport, and endows the membrane with ultra-high water permeability, which helps to improve the efficiency of water production and water reuse.
[0019] (2) In the process of scaling up the application of ultra-high water permeability polyester reverse osmosis membrane formulation based on artificial water channels, only the traditional aqueous monomer m-phenylenediamine needs to be replaced with OH-ExR4 without changing the overall membrane manufacturing process, which is easy to scale up production. Attached Figure Description
[0020] Figure 1 These are scanning electron microscope images of the surfaces of four polyester reverse osmosis membranes prepared in Comparative Example 1 and Examples 1-3.
[0021] Figure 2 The comparison is between the water permeability and NaCl retention of Comparative Example 1, Examples 1-3 and the commercial reverse osmosis membrane BW30. Detailed Implementation
[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.
[0023] Example 1 This embodiment provides an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels and its preparation method, as detailed below: (1) Preparation of precursor Me-ExR4: S1. A certain amount of 1,4-bis(chloromethyl)benzene was dissolved in dichloromethane to obtain a solution with a concentration of 17.5 g / L. Then, 1,3-dimethoxybenzene and AlCl3 were added sequentially to make their concentrations 55 g / L and 40 g / L, respectively. The reaction was carried out under nitrogen atmosphere and stirred at room temperature for 45 min. After the reaction was completed, water was added to the solution to quench the reaction, and the solution was extracted with dichloromethane. Then, the solution was washed with saturated brine, dried over anhydrous sodium sulfate, and purified by chromatographic column separation to obtain 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene.
[0024] S2. The obtained 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene was dissolved in dichloromethane to obtain a solution with a concentration of 2 g / L. Paraformaldehyde (300~3000 Da) was then added to bring the concentration to 0.64 g / L. The mixture was stirred at room temperature under nitrogen atmosphere for 10 min, followed by the dropwise addition of a certain amount of trifluoroacetic acid to bring the concentration to 3.4 g / L, and the reaction was continued for another 30 min. After the reaction was completed, 1 M NaOH solution was added to quench the reaction. The solution was then washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain the crude product. The crude product was recrystallized / ground with acetonitrile to obtain Me-ExR4.
[0025] (2) Preparation of artificial water channel OH-ExR4: Me-ExR4 was dissolved in dichloromethane to obtain a solution with a concentration of 8.8 g / L. After cooling in an ice-water bath for 10 min, BBr3 was added to the solution to make its concentration 28 g / L. The reaction was carried out under nitrogen atmosphere at 25°C with stirring for 16 h. After the reaction was completed, water was slowly added to the reaction system to quench it, and stirring was continued for 3 h. The solid was then collected by filtration and purified by recrystallization with acetone and water to obtain OH-ExR4.
[0026] (3) Preparation of OH-ExR4 aqueous solution: Mix a certain amount of OH-ExR4 with water to obtain a solution with a concentration of 10 g / L; then add a certain amount of NaOH to the solution to make the NaOH concentration 2.5 g / L, and sonicate for 30 min to obtain OH-ExR4 aqueous solution.
[0027] (4) Base film wetting: The polyethersulfone base film was treated in 10 g / L OH-ExR4 aqueous solution for 5 min, and then the excess solution on the film surface was removed.
[0028] (5) Interfacial polymerization: The surface of the base film after step (4) is treated with a 0.2 wt / v% hexane solution of trimesoyl chloride for 15 min. The excess solution on the film surface is poured off. Then, the film is washed multiple times with hexane solution and deionized water, and the film is treated in a vacuum drying oven at 40℃ for 2 min.
[0029] Example 2 This embodiment provides an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels and its preparation method, as detailed below: (1) Preparation of precursor Me-ExR4: S1. A certain amount of 1,4-bis(chloromethyl)benzene was dissolved in dichloromethane to obtain a solution with a concentration of 17.5 g / L. Then, 1,3-dimethoxybenzene and AlCl3 were added sequentially to make their concentrations 55 g / L and 40 g / L, respectively. The reaction was carried out under nitrogen atmosphere and stirred at room temperature for 45 min. After the reaction was completed, water was added to the solution to quench the reaction, and the solution was extracted with dichloromethane. Then, the solution was washed with saturated brine, dried over anhydrous sodium sulfate, and purified by chromatographic column separation to obtain 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene.
[0030] S2. The obtained 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene was dissolved in dichloromethane to obtain a solution with a concentration of 2 g / L. Paraformaldehyde (300~3000 Da) was then added to bring the concentration to 0.64 g / L. The mixture was stirred at room temperature under nitrogen atmosphere for 10 min, followed by the dropwise addition of a certain amount of trifluoroacetic acid to bring the concentration to 3.4 g / L, and the reaction was continued for another 30 min. After the reaction was completed, 1 M NaOH solution was added to quench the reaction. The solution was then washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain the crude product. The crude product was recrystallized / ground with acetonitrile to obtain Me-ExR4.
[0031] (2) Preparation of artificial water channel OH-ExR4: Me-ExR4 was dissolved in dichloromethane to obtain a solution with a concentration of 8.8 g / L. After cooling in an ice-water bath for 10 min, BBr3 was added to the solution to make its concentration 28 g / L. The reaction was carried out under nitrogen atmosphere at 25°C with stirring for 16 h. After the reaction was completed, water was slowly added to the reaction system to quench it, and stirring was continued for 3 h. The solid was then collected by filtration and purified by recrystallization with acetone and water to obtain OH-ExR4.
[0032] (3) Preparation of OH-ExR4 aqueous solution: A certain amount of OH-ExR4 was mixed with water to obtain a solution with a concentration of 20 g / L; then a certain amount of NaOH was added to the solution to make the NaOH concentration 5 g / L, and the solution was sonicated for 30 min to obtain OH-ExR4 aqueous solution.
[0033] (4) Base film wetting: The polyethersulfone membrane was treated in 20 g / L OH-ExR4 aqueous solution for 5 min, and then the excess solution on the membrane surface was removed.
[0034] (5) Interfacial polymerization: The surface of the base film after step (4) is treated with a 0.2 wt / v% hexane solution of trimesoyl chloride for 15 min. The excess solution on the film surface is poured off. Then, the film is washed multiple times with hexane solution and deionized water, and the film is treated in a vacuum drying oven at 40℃ for 2 min.
[0035] Example 3 This embodiment provides an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels and its preparation method, as detailed below: (1) Preparation of precursor Me-ExR4: S1. A certain amount of 1,4-bis(chloromethyl)benzene was dissolved in dichloromethane to obtain a solution with a concentration of 17.5 g / L. Then, 1,3-dimethoxybenzene and AlCl3 were added sequentially to make their concentrations 55 g / L and 40 g / L, respectively. The reaction was carried out under nitrogen atmosphere and stirred at room temperature for 45 min. After the reaction was completed, water was added to the solution to quench the reaction, and the solution was extracted with dichloromethane. Then, the solution was washed with saturated brine, dried over anhydrous sodium sulfate, and purified by chromatographic column separation to obtain 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene.
[0036] S2. The obtained 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene was dissolved in dichloromethane to obtain a solution with a concentration of 2 g / L. Paraformaldehyde (300~3000 Da) was then added to bring the concentration to 0.64 g / L. The mixture was stirred at room temperature under nitrogen atmosphere for 10 min, followed by the dropwise addition of a certain amount of trifluoroacetic acid to bring the concentration to 3.4 g / L, and the reaction was continued for another 30 min. After the reaction was completed, 1 M NaOH solution was added to quench the reaction. The solution was then washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain the crude product. The crude product was recrystallized / ground with acetonitrile to obtain Me-ExR4.
[0037] (2) Preparation of artificial water channel OH-ExR4: Me-ExR4 was dissolved in dichloromethane to obtain a solution with a concentration of 8.8 g / L. After cooling in an ice-water bath for 10 min, BBr3 was added to the solution to make its concentration 28 g / L. The reaction was carried out under nitrogen atmosphere at 25°C with stirring for 16 h. After the reaction was completed, water was slowly added to the reaction system to quench it, and stirring was continued for 3 h. The solid was then collected by filtration and purified by recrystallization with acetone and water to obtain OH-ExR4.
[0038] (3) Preparation of OH-ExR4 aqueous solution: A certain amount of OH-ExR4 was mixed with water to obtain a solution with a concentration of 30 g / L; then a certain amount of NaOH was added to the solution to make the NaOH concentration 7.5 g / L, and the solution was sonicated for 30 min to obtain OH-ExR4 aqueous solution.
[0039] (4) Wetting of polyethersulfone membrane: The base membrane was treated in 30 g / L OH-ExR4 solution for 5 min, and then the excess solution on the membrane surface was removed.
[0040] (5) Interfacial polymerization: The surface of the base film after step (4) is treated with a 0.2 wt / v% hexane solution of trimesoyl chloride for 15 min. The excess solution on the film surface is poured off. Then, the film is washed multiple times with hexane solution and deionized water, and the film is treated in a vacuum drying oven at 40℃ for 2 min.
[0041] Comparative Example 1 This comparative example provides an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels and its preparation method, as detailed below: The preparation method is similar to that in Example 1, except that: (3) Preparation of OH-ExR4 aqueous solution: Mix a certain amount of OH-ExR4 with water to obtain a solution with a concentration of 5 g / L; then add a certain amount of NaOH to the solution to make the NaOH concentration 1.25 g / L, and sonicate for 30 min to obtain OH-ExR4 aqueous solution.
[0042] (4) Base membrane wetting: The base membrane was treated in 5 g / L OH-ExR4 aqueous solution for 5 min, and then the excess solution on the membrane surface was removed.
[0043] (5) Interfacial polymerization: The surface of the base film after step (4) is treated with a 0.2 wt / v% hexane solution of trimesoyl chloride for 15 min. The excess solution on the film surface is poured off. Then, the film is washed multiple times with hexane solution and deionized water, and the film is treated in a vacuum drying oven at 40℃ for 2 min.
[0044] Comparative Example 2 This comparative example provides a commercial BW30 membrane.
[0045] Test Example 1 Surface morphology: Figure 1 As shown in the scanning electron microscope observation, compared with Comparative Example 1, Example 1 has a wrinkled structure on its surface, and the wrinkled structure becomes more pronounced with the increase of OH-ExR4 concentration. The wrinkled structure helps to increase the water molecule transport area and improve the water permeability of the membrane.
[0046] Test Example 2 Pure water permeability and NaCl retention: The membrane samples obtained from Comparative Examples 1-2 and Examples 1, 2, and 3 were pre-pressurized with pure water at an operating pressure of 16 bar for 2 hours. The test was conducted under cross-flow filtration conditions with an operating pressure of 16 bar, a water temperature of 25°C, and a cross-flow velocity of 22.4 cm / s. The effluent volume of the membrane samples was measured within the same time period, and the pure water permeability was calculated. The test results are as follows: Figure 2 As shown; the membrane samples obtained from Comparative Examples 1-2 and Examples 1, 2, and 3 were pre-pressurized with pure water at an operating pressure of 16 bar for 2 h, and a 2 g / L NaCl aqueous solution was prepared. The test was conducted under cross-flow filtration conditions with an operating pressure of 16 bar, a water temperature of 25°C, and a cross-flow velocity of 22.4 cm / s. The NaCl concentrations of the feed solution and permeate were measured based on conductivity, and the NaCl rejection rate was calculated. The test results are shown below. Figure 2 As shown.
[0047] Depend on Figure 2 As can be seen, Example 2 exhibits the highest NaCl rejection (~94%), consistent with the properties of a reverse osmosis membrane, and shows no significant difference in NaCl rejection compared to the commercial BW30 membrane. Notably, Example 2 achieves a water permeability of 10.2 L·m⁻¹. -2 ·h -1 ·bar -1 The water permeability is far higher than that of existing reverse osmosis membranes. The results show that using artificial water channels as aqueous monomers for interfacial polymerization can significantly increase the artificial water channel loading in the reverse osmosis membrane. At the same time, the inherent pores of the water channels serve as the main pores of the reverse osmosis membrane, thereby fully utilizing the excellent water flow characteristics of the water channels, inducing water molecule chain transport, and endowing the formed reverse osmosis membrane with ultra-high water permeability, which helps to improve the efficiency of water production and water reuse.
[0048] The embodiments described above are merely preferred embodiments for fully illustrating the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.
Claims
1. A method for preparing an ultra-high water permeability polyester reverse osmosis membrane based on artificial water channels, characterized in that, Includes the following steps: A precursor, fully methoxylated phenyl extended calix [4] resorcinol aromatic hydrocarbon Me-ExR4, is provided; The fully hydroxylated phenyl extended calix [4] resorcinol OH-ExR4 was prepared by demethylation reaction; Using OH-ExR4 as an aqueous monomer for interfacial polymerization, an aqueous solution containing OH-ExR4 was prepared. The aqueous solution containing OH-ExR4 was used to wet the surface of the base membrane, and then a hexane solution of trimesoyl chloride was applied to the surface of the base membrane to induce an OH-ExR4-mediated acylation reaction, thereby obtaining the ultra-high water permeability polyester reverse osmosis membrane.
2. The preparation method according to claim 1, characterized in that, The fully methoxylated phenyl extended calix [4] resorcinol aromatic hydrocarbon Me-ExR4 was prepared by the following method: S1. Add 1,3-dimethoxybenzene and AlCl3 to a 1,4-bis(chloromethyl)benzene solution to obtain a first mixed solution; stir the reaction under an inert atmosphere; after the reaction is completed, add a quencher to quench the reaction to obtain 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene; S2. Dissolve the obtained 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene in an organic solvent to obtain a second mixed solution. Add paraformaldehyde to obtain a third mixed solution. Stir and mix under an inert atmosphere, add trifluoroacetic acid to obtain a fourth mixed solution, and continue the reaction for 30-60 min. After the reaction is completed, add a quencher to quench the reaction to obtain Me-ExR4.
3. The preparation method according to claim 2, characterized in that, In step S1, the inert gases in the inert atmosphere include nitrogen and / or argon, the stirring reaction time is 5-30 min, and the temperature is room temperature; the quenching agent is water.
4. The preparation method according to claim 2, characterized in that, In step S1, the concentration of 1,3-dimethoxybenzene in the first mixed solution is 30~60 g / L, and the concentration of AlCl3 is 30~50 g / L; The concentration of the 1,4-bis(chloromethyl)benzene solution is 5~20 g / L.
5. The preparation method according to claim 2, characterized in that, In step S2, the concentration of 4-(4-(2,4-dimethoxybenzyl)benzyl)-1,2-dimethoxybenzene in the second mixed solution is 1~5 g / L; The concentration of paraformaldehyde in the third mixed solution is 0.2~0.8 g / L; The concentration of trifluoroacetic acid in the fourth mixed solution is 1~4 g / L; The organic solvent includes one or more of dichloromethane, 1,2-dichloroethane, and chloroform; The mixing time is 5-30 minutes, and the temperature is room temperature. The quenching agent is a sodium hydroxide solution with a concentration of 0.5~2 M.
6. The preparation method according to claim 1, characterized in that, The conditions for the demethylation reaction are as follows: cool the Me-ExR4 solution in an ice bath for 5-20 min, add BBr3, and stir the reaction at 25-40℃ for 8-24 h under an inert atmosphere.
7. The preparation method according to claim 6, characterized in that, The concentration of the Me-ExR4 solution is 5~10 g / L, and the concentration of BBr3 is 15~30 g / L.
8. The preparation method according to claim 1, characterized in that, The concentration of OH-ExR4 in the aqueous solution containing OH-ExR4 is 5~30 g / L; The aqueous solution containing OH-ExR4 also includes NaOH at a concentration of 1.25~7.5 g / L.
9. The preparation method according to claim 1, characterized in that, The base membrane is selected from polysulfone membrane, polyethersulfone membrane, or polyvinylidene fluoride membrane; The acylation reaction takes 1-20 min at a temperature of 20-30℃. The concentration of the hexane solution of pyromellitic methyl chloride is 0.1~0.5 wt / v.
10. A high water permeability polyester reverse osmosis membrane based on artificial water channels, characterized in that, Prepared by the preparation method described in any one of claims 1 to 9.