Composite reverse osmosis membrane based on diazonaphthone-containing polyarylethersulfone-based membrane and its preparation method

Abstract

This invention pertains to membrane preparation technology and discloses a composite reverse osmosis membrane based on a diazanaphthone-structured polyarylether sulfone base membrane and its preparation method. The method involves using a diazanaphthone-structured polyarylether sulfone and a chloromethylated polyarylether sulfone blended ultrafiltration membrane as the base membrane. An ultrathin polyamide separation layer is then laminated onto the surface of the ultrafiltration base membrane using interfacial polymerization. This separation layer is prepared by interfacial polymerization of a polyamine and an acyl chloride monomer. The polyamine in the aqueous phase reacts with the chloromethyl group on the base membrane surface, achieving chemical bonding between the base membrane and the active layer, significantly improving the stability of the reverse osmosis membrane. Furthermore, because the diazanaphthone-structured polyarylether sulfone molecular chain in the base membrane contains a twisted, non-coplanar diazanaphthone structure with a fully aromatic ring, it exhibits a high glass transition temperature and excellent chemical stability. The prepared composite reverse osmosis membrane possesses high-temperature resistance, providing a valuable reference for addressing the problem of insufficient stability in reverse osmosis membranes.

Description

Technical Field

[0001] This invention pertains to separation membrane preparation technology, specifically to a composite reverse osmosis membrane based on a polyarylene ether sulfone membrane containing a diazanaphthone structure and its preparation method. Background Technology

[0002] Reverse osmosis membranes, as an important branch of membrane separation technology, have a history dating back to the 1950s. In 1953, American scientists Reid and Bretron first proposed the concept of reverse osmosis. Utilizing the selective separation effect of a semi-permeable membrane, under conditions higher than the osmotic pressure of the solution, and driven by external pressure, the solvent (usually water) flows through the membrane from the side with a high concentration of solute to the side with a low concentration, thus achieving efficient separation of solute and solvent. In 1960, Loeb and Sourirajan prepared the first generation of reverse osmosis membranes (asymmetric cellulose acetate membranes) using a phase inversion method. This membrane had an asymmetric structure with a dense surface layer and a porous support layer, significantly improving membrane separation performance and laying an important foundation for modern reverse osmosis technology. In the 1970s, Cadotte et al. developed polyamide composite reverse osmosis membranes by forming an ultrathin separation layer on the surface of the base membrane through interfacial polymerization. This novel composite structure combines high desalination rate and high flux, gradually replacing cellulose acetate membranes as the mainstream technology. With advancements in materials science and manufacturing processes, composite reverse osmosis membranes are increasingly being used in seawater desalination, wastewater treatment, food and pharmaceutical fields, driving continuous innovation and development in membrane separation technology.

[0003] In special fields such as chemical wastewater treatment, the requirements for high temperature resistance and acid and alkali resistance of composite reverse osmosis membranes are high. At present, most commercial composite reverse osmosis membranes face the problem of insufficient stability. First, the base membrane material of commercial composite reverse osmosis membranes will undergo polymer chain breakage when exposed to oxidants or extreme pH solutions for a long time; second, under high pressure and temperature fluctuations, the active layer of the composite reverse osmosis membrane may peel off from the base membrane. These stability problems not only shorten the membrane life, but also limit the application of commercial composite reverse osmosis membranes in various harsh environments. In recent years, researchers have begun to use polymer blending methods to combine the advantages of different materials to prepare high-performance composite reverse osmosis membrane base membranes, pointing out a new direction for the development of composite reverse osmosis membranes. Wei Ju et al. (Acta Polymerica Sinica, 2006, (2): 298-302) prepared a naphthalene-biphenyl polyethersulfone ketone / sulfonated naphthalene-biphenyl polyethersulfone ketone blended ultrafiltration base membrane by solution blending method, and used it to prepare a composite reverse osmosis membrane. Both polymers contain a fully aromatic ring-twisted, non-coplanar diazanaphthone structure, exhibiting good heat resistance and improving the heat resistance of the base membrane. The sulfonated naphthalene-biphenyl polyethersulfone ketone contains hydrophilic sulfonic acid groups, enhancing the hydrophilicity of the ultrafiltration base membrane and thus increasing the water flux of the composite reverse osmosis membrane. However, currently, there is no strong interaction between the base membrane and the active separation layer of the composite reverse osmosis membrane, and the bonding strength still needs to be improved to enhance its stability.

[0004] This invention uses chloromethylated polyarylene ether sulfone and diazanaphthone-containing polyarylene ether sulfone as base membrane materials, and prepares a polyamide composite reverse osmosis membrane based on the diazanaphthone-containing polyarylene ether sulfone base membrane using an interfacial polymerization method. The diazanaphthone-containing polyarylene ether sulfone has a high glass transition temperature, which is beneficial for maintaining the heat resistance of the base membrane. The introduction of chloromethyl groups into the base membrane allows for chemical bonding between the base membrane support layer and the active layer of the composite membrane through reaction with aqueous amine monomers, potentially improving the stability of the reverse osmosis membrane. Summary of the Invention

[0005] This invention pertains to membrane preparation technology and provides a method for preparing a polyamide composite reverse osmosis membrane based on a polyarylene ether sulfone-based membrane containing a diazanaphthone structure.

[0006] The technical solution of the present invention:

[0007] A composite reverse osmosis membrane based on a polyarylene ether sulfone membrane containing a diazanaphthone structure, using a blend of chloromethylated polyarylene ether sulfone and a polyarylene ether sulfone membrane containing a diazanaphthone structure as the base membrane;

[0008] 1) The structural formula of chloromethylated polyarylether sulfone is:

[0009]

[0010] Where X is The structural formula of polyarylether sulfone containing a diazanaphthone structure is:

[0011]

[0012] Where Y is R1, R2, R3, and R4 are hydrogen atoms, halogen atoms, methyl groups, or aryl groups, and may be the same or different.

[0013] A method for preparing a composite reverse osmosis membrane based on a diazanaphthone-structured polyarylene ether sulfone membrane, comprising the following steps:

[0014] A blended ultrafiltration membrane of chloromethylated polyarylene ether sulfone and diazanaphthone-containing polyarylene ether sulfone was selected as the base membrane. A polyamine was dissolved in deionized water, and after complete dissolution, an aqueous phase additive was added to prepare an aqueous solution. The polyamine accounted for 0.1–5% of the mass of the aqueous solution, and the aqueous phase additive accounted for 0–5% of the mass of the aqueous solution. An acyl chloride monomer was dissolved in an alkane-based organic solvent to prepare an oil phase solution, wherein the acyl chloride monomer accounted for 0.01–5% of the mass of the oil phase solution.

[0015] Under ambient temperatures of 10–50°C and humidity of 20–80%, the dried base membrane is immersed in an aqueous solution for 0.5–20 min to allow the base membrane to fully adsorb the aqueous solution, and for the polyamine in the aqueous solution to react with the chloromethyl groups on the surface of the base membrane. The base membrane is then removed and air-dried until excess aqueous solution is removed from the membrane surface. It is then placed in an organic solution for interfacial polymerization at 10–80°C for 5–200 s. After polymerization, the membrane is removed and air-dried to obtain a nascent composite membrane. The nascent composite membrane is then post-treated at 20–120°C for 0–60 min to obtain a composite reverse osmosis membrane based on a polyarylene ether sulfone base membrane containing a diazanaphthone structure.

[0016] The ultrafiltration membrane blended with chloromethylated polyarylene ether sulfone and diazanaphthone-containing polyarylene ether sulfone is prepared by solution blending of chloromethylated polyarylene ether sulfone and diazanaphthone-containing polyarylene ether sulfone using a phase inversion method, wherein the mass ratio of chloromethylated polyarylene ether sulfone to diazanaphthone-containing polyarylene ether sulfone is 1:1 to 1:50; the specific preparation process is as follows:

[0017] 1) Add additives and solvents to chloromethylated polyarylene ether sulfone and polyarylene ether sulfone containing diazanaphthone structure, mix and stir until completely dissolved to obtain a homogeneous and stable casting solution; wherein, the total mass of chloromethylated polyarylene ether sulfone and polyarylene ether sulfone containing diazanaphthone structure accounts for 5-30% of the mass fraction of the casting solution, the additives account for 0-30% of the mass fraction of the casting solution, and the solvent accounts for 40-95% of the mass fraction of the casting solution;

[0018] 2) The membrane is scraped under the conditions of ambient temperature of 10-50℃ and humidity of 20-80%; after the solvent in the casting solution evaporates for 0-5 minutes, it is placed in a gel bath at a temperature of 0-50℃, with the additives in the gel bath accounting for 0-10wt%, and gelled into an ultrafiltration membrane. The solvent and additives are washed away by soaking in water to obtain a blended ultrafiltration membrane of chloromethylated polyarylene ether sulfone and polyarylene ether sulfone containing diazanaphthone structure.

[0019] in,

[0020] The additive is one or a mixture of two or more of ethylene glycol methyl ether, ethanol, ethylene glycol, glycerin, polyethylene glycol, and polyvinylpyrrolidone;

[0021] The solvent is one or a mixture of two or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and dimethyl sulfoxide;

[0022] The additives in the gel bath are one or more of the following: inorganic salts, organic solvents, acids, and bases.

[0023] The inorganic salt is NaCl, LiCl, or CaCl2; the organic solvent is ethanol or isopropanol; the acid is HCl; and the base is NaOH.

[0024] The polyamine is one or a mixture of two or more of the following: m-phenylenediamine, p-phenylenediamine, benzidine (such as 4,4'-diaminobiphenyl), and pyromellitic triamine.

[0025] The aqueous phase additive is one or a mixture of two or more of the following: triethylamine, sodium carbonate, sodium dodecyl sulfate, Tween-80, and camphor sulfonic acid.

[0026] The acyl chloride monomer is one or a mixture of two or more of isophthaloyl chloride, terephthaloyl chloride, pyromellitic trichloromethyl chloride, and pyromellitic tetrachloromethyl chloride.

[0027] The alkane organic solvent is one or a mixture of two or more of n-hexane, cyclohexane, n-heptane, n-decane, and isoalkanes.

[0028] The beneficial effects of this invention are:

[0029] (1) The present invention uses a blend of chloromethylated polyarylene ether sulfone and polyarylene ether sulfone containing diazanaphthone structure as the base membrane. The base membrane surface contains chloromethyl groups. When immersed in a polyamine aqueous solution, the chloromethyl groups react with the amine groups. After interfacial polymerization, chemical bonding between the base membrane support layer and the active layer of the composite membrane can be achieved, thereby improving the stability of the reverse osmosis membrane.

[0030] (2) This invention prepares a composite reverse osmosis membrane based on a polyarylether sulfone base membrane containing a diazanaphthone structure. The polyarylether sulfone containing a diazanaphthone structure has a high glass transition temperature, which is beneficial for improving the heat resistance of the base membrane. By blending chloromethylated polyarylether sulfone and the polyarylether sulfone containing a diazanaphthone structure, chloromethyl groups are introduced onto the surface of the base membrane. These chloromethyl groups react with the polyamines in the aqueous phase, achieving chemical bonding between the base membrane and the active layer. This improves the bonding stability between the reverse osmosis membrane support layer and the separation layer, thereby enhancing the heat resistance of the composite reverse osmosis membrane. Attached Figure Description

[0031] Figure 1 These are the proton NMR spectra before and after CMPES amination treatment.

[0032] Figure 2 These are the infrared spectra of the CMPES / PPBES base film before and after amination treatment. Detailed Implementation

[0033] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and technical solutions.

[0034] Example 1

[0035] Ultrafiltration membranes were prepared by blending biphenyl-type naphthalene-biphenyl copolymer aryl ether sulfone (PPBES) and chloromethylated polyether sulfone (CMPES). Their structural formulas are as follows:

[0036]

[0037] Weigh out 3.0 g of dried biphenyl-type naphthalene-biphenyl copolymer aryl ether sulfone (PPBES) and 0.2 g of chloromethylated polyether sulfone (CMPES). Use N,N-dimethylacetamide (13.6 g) as solvent and add 3.2 g of ethylene glycol methyl ether as additive. Stir until the polymer is completely dissolved to obtain a homogeneous and stable casting solution. At an ambient temperature of 25°C and a humidity of 30%, coat a certain thickness of the casting solution onto a glass plate or nonwoven fabric support. Expose it to air, allowing the solvent to evaporate for 10 seconds. Then immerse it in a 25°C deionized hydrogel bath to undergo phase inversion and membrane formation. After washing away the solvent and additive, a blended ultrafiltration membrane of chloromethylated polyether sulfone and biphenyl-type naphthalene-biphenyl copolymer aryl ether sulfone is obtained.

[0038] A blended ultrafiltration membrane of chloromethylated polyarylene ether sulfone (CMPES) and diazanaphthone-containing polyarylene ether sulfone (PPBES) in a mass ratio of 1:15 (CMPES / PPBES-1) was prepared. The ultrafiltration membrane achieved a bovine serum albumin (BSA) rejection rate of 99.0% and a water flux of 290.5 L·m⁻¹. -2· h -1 .

[0039] Weigh out m-phenylenediamine (MPD, 2.0 g) and dissolve it in 95.9 g of deionized water. After complete dissolution, add sodium dodecyl sulfate (SDS, 0.1 g) and triethylamine (TEA, 2.0 g). Stir at room temperature until completely dissolved to prepare an aqueous phase solution, wherein the mass fraction of MPD in the aqueous phase solution is 2.0%, the mass fraction of SDS in the aqueous phase solution is 0.1%, and the mass fraction of TEA in the aqueous phase solution is 2.0%. Weigh out trimesoyl chloride (TMC, 0.15 g) and dissolve it in 99.85 g of n-hexane organic solvent. Stir at room temperature until completely dissolved to prepare an organic phase solution, wherein the acyl chloride accounts for 0.15% of the mass fraction of the oil phase solution.

[0040] Under ambient temperatures of 25℃ and humidity of 30%, a CMPES / PPBES-1 blended ultrafiltration membrane was used as the base membrane. The base membrane was immersed in an aqueous solution for 1 minute to allow for full adsorption of the aqueous solution, and the polyamines in the aqueous phase reacted with the chloromethyl groups on the base membrane surface. The base membrane was then removed and air-dried to remove excess aqueous solution from the membrane surface. The membrane was then placed in an organic phase solution for interfacial polymerization. After polymerization for 60 seconds, it was removed and air-dried to obtain a nascent composite membrane. The nascent composite membrane was then treated at 60℃ for 10 minutes to obtain a polyamide composite reverse osmosis membrane based on a diazanaphthone-structured polyarylene ether sulfone base membrane. At 25℃ and an operating pressure of 1.6 MPa, the water flux of the reverse osmosis membrane was 26.3 L·m⁻¹. -2 ·h -1 The desalination rate of NaCl is 99.2%.

[0041] The structures of CMPES and CMPES / PPBES ultrafiltration membranes before and after immersion in an aqueous solution were characterized by NMR (nuclear magnetic resonance) analysis. Figure 1 ) and infrared spectrum ( Figure 2 It can be seen that the chloromethyl group on the surface of the CMPES / PPBES base membrane reacted with the amino group of m-phenylenediamine. After treating the composite reverse osmosis membrane in boiling water for 30 minutes, the water flux of the reverse osmosis membrane increased from 26.3 L·m⁻¹. -2 ·h -1 Rising to 34.1 L·m -2 ·h -1 The desalination rate only decreased from 99.2% to 99.0%, remaining essentially stable. This indicates that the composite reverse osmosis membrane possesses good heat resistance and stability.

[0042] Comparative Example 1

[0043] Using the PPBES ultrafiltration membrane prepared in Example 1 as the base membrane, the ultrafiltration membrane achieved a BSA rejection rate of 99.4% and a water flux of 285.2 L·m⁻¹. -2 ·h -1 Weigh out m-phenylenediamine (MPD, 2.0 g) and dissolve it in 95.9 g of deionized water. After complete dissolution, add sodium dodecyl sulfate (SDS, 0.1 g) and triethylamine (TEA, 2.0 g), and stir at room temperature until completely dissolved to prepare an aqueous phase solution. The mass fraction of MPD in the aqueous phase solution is 2.0%, the mass fraction of SDS in the aqueous phase solution is 0.1%, and the mass fraction of TEA in the aqueous phase solution is 2.0%. Weigh out trimesoyl chloride (TMC, 0.15 g) and dissolve it in 99.85 g of n-hexane organic solvent. Stir at room temperature until completely dissolved to prepare an organic phase solution. The mass fraction of the acyl chloride in the oil phase solution is 0.15%.

[0044] Under ambient temperatures of 25℃ and humidity of 30%, the PPBES base membrane was immersed in an aqueous solution for 1 minute to allow it to fully absorb the aqueous solution. The membrane was then removed, air-dried, and excess aqueous solution was removed from the membrane surface. The membrane was then placed in an organic solution for interfacial polymerization. After polymerization for 60 seconds, it was removed and air-dried to obtain a nascent composite membrane. The nascent composite membrane was post-treated at 60℃ for 10 minutes to obtain a polyamide composite reverse osmosis membrane. At an operating pressure of 1.6 MPa and an operating temperature of 25℃, the water flux of the reverse osmosis membrane was 15.0 L·m³. -2 ·h -1 The membrane achieved a NaCl desalination rate of 97.0%.

[0045] Comparing Example 1 and Comparative Example 1, it is evident that the composite reverse osmosis membrane prepared using a blend of chloromethylated polyethersulfone and biphenyl-type naphthalene-biphenyl copolymer ethersulfone as the base membrane exhibits higher water flux and desalination rate than the reverse osmosis membrane prepared using the same ultrafiltration membrane. This indicates that the composite reverse osmosis membrane prepared using the blend of chloromethylated polyethersulfone and biphenyl-type naphthalene-biphenyl copolymer ethersulfone as the base membrane demonstrates higher permeation selectivity.

[0046] Example 2

[0047] A blended ultrafiltration membrane of chloromethylated polyarylene ether sulfone (CMPES) / diazaphenazone-containing polyarylene ether sulfone (PPBES-2) was prepared according to the preparation method of Example 1, wherein the mass ratio of chloromethylated polyarylene ether sulfone (CMPES) to diazaphenazone-containing polyarylene ether sulfone (PPBES) was 1:30. The ultrafiltration membrane had a BSA rejection rate of 99.6% and a water flux of 301.9 L·m -2· h -1 .

[0048] Weigh out m-phenylenediamine (MPD, 2.0 g) and dissolve it in 95.9 g of deionized water. After complete dissolution, add sodium dodecyl sulfate (SDS, 0.1 g) and triethylamine (TEA, 2.0 g). Stir at room temperature until completely dissolved to prepare an aqueous phase solution, wherein the mass fraction of MPD in the aqueous phase solution is 2.0%, the mass fraction of SDS in the aqueous phase solution is 0.1%, and the mass fraction of TEA in the aqueous phase solution is 2.0%. Weigh out trimesoyl chloride (TMC, 0.15 g) and dissolve it in 99.85 g of n-hexane organic solvent. Stir at room temperature until completely dissolved to prepare an organic phase solution, wherein the acyl chloride accounts for 0.15% of the mass fraction of the oil phase solution.

[0049] Under ambient temperatures of 25℃ and humidity of 30%, a CMPES / PPBES-2 blended ultrafiltration membrane was used as the base membrane. The base membrane was immersed in an aqueous solution for 1 minute to allow for full adsorption of the aqueous solution, and the polyamines in the aqueous phase reacted with the chloromethyl groups on the base membrane surface. The base membrane was then removed and air-dried to remove excess aqueous solution from the membrane surface. The membrane was then placed in an organic phase solution for interfacial polymerization. After polymerization for 60 seconds, it was removed and air-dried to obtain a nascent composite membrane. The nascent composite membrane was post-treated at 60℃ for 10 minutes to obtain a polyamide composite reverse osmosis membrane based on a diazanaphthone-structured polyarylene ether sulfone base membrane. At an operating pressure of 1.6 MPa and an operating temperature of 25℃, the water flux of the reverse osmosis membrane was 24.1 L·m³. -2 ·h -1 The membrane has a NaCl rejection rate of 99.1%.

[0050] Example 3

[0051] The CMPES / PPBES-1 blended ultrafiltration membrane was prepared according to the preparation method of Example 1;

[0052] Weigh out m-phenylenediamine (MPD, 2.0 g) and dissolve it in 95.9 g of deionized water. After complete dissolution, add sodium dodecyl sulfate (SDS, 0.1 g) and triethylamine (TEA, 2.0 g). Stir at room temperature until completely dissolved to prepare an aqueous solution. The mass fraction of MPD in the aqueous solution is 2.0%, the mass fraction of SDS in the aqueous solution is 0.1%, and the mass fraction of TEA in the aqueous solution is 2.0%. Weigh out trimesoyl chloride (TMC, 0.25 g) and dissolve it in 99.75 g of n-hexane organic solvent. Stir at room temperature until completely dissolved to prepare an organic solution. The mass fraction of the acyl chloride in the oil phase solution is 0.25%.

[0053] Under ambient temperatures of 25℃ and humidity of 30%, a CMPES / PPBES-1 blended ultrafiltration membrane was used as the base membrane. It was immersed in an aqueous solution for 1 minute to allow the base membrane to fully adsorb the aqueous solution, and for the polyamines in the aqueous phase to react with the chloromethyl groups on the base membrane surface. The base membrane was then removed, air-dried, and excess aqueous solution was removed from the membrane surface. The membrane was then placed in an organic phase solution for interfacial polymerization. After polymerization for 60 seconds, it was removed and air-dried to obtain a nascent composite membrane. The nascent composite membrane was post-treated at 60℃ for 10 minutes to obtain a polyamide composite reverse osmosis membrane based on a diazanaphthone-structured polyarylene ether sulfone base membrane. At an operating pressure of 1.6 MPa and an operating temperature of 25℃, the water flux of the reverse osmosis membrane was 25.9 L·m⁻¹. -2 ·h -1 The membrane achieved a NaCl desalination rate of 99.3%.

[0054] Example 4

[0055] The CMPES / PPBES-1 blended ultrafiltration membrane was prepared according to the preparation method of Example 1;

[0056] Weigh out m-phenylenediamine (MPD, 2.0 g) and dissolve it in 95.9 g of deionized water. After complete dissolution, add sodium dodecyl sulfate (SDS, 0.1 g) and triethylamine (TEA, 2.0 g). Stir at room temperature until completely dissolved to prepare an aqueous phase solution, wherein the mass fraction of MPD in the aqueous phase solution is 2.0%, the mass fraction of SDS in the aqueous phase solution is 0.1%, and the mass fraction of TEA in the aqueous phase solution is 2.0%. Weigh out trimesoyl chloride (TMC, 0.15 g) and dissolve it in 99.85 g of n-hexane organic solvent. Stir at room temperature until completely dissolved to prepare an organic phase solution, wherein the acyl chloride accounts for 0.15% of the mass fraction of the oil phase solution.

[0057] Under ambient temperatures of 25℃ and humidity of 30%, a CMPES / PPBES-1 blended ultrafiltration membrane was used as the base membrane. The base membrane was immersed in an aqueous solution for 1 minute to allow for full adsorption of the aqueous solution, and the polyamines in the aqueous phase reacted with the chloromethyl groups on the surface of the base membrane. The base membrane was then removed, air-dried, and excess aqueous solution was removed from the membrane surface. The membrane was then placed in an organic phase solution for interfacial polymerization. After polymerization for 40 seconds, it was removed and air-dried to obtain a nascent composite membrane. The nascent composite membrane was post-treated at 60℃ for 10 minutes to obtain a polyamide composite reverse osmosis membrane based on a diazanaphthone-structured polyarylene ether sulfone base membrane. At an operating pressure of 1.6 MPa and an operating temperature of 25℃, the water flux of the reverse osmosis membrane was 31.2 L·m⁻¹. -2 ·h -1 The membrane achieved a NaCl desalination rate of 97.1%.

Claims

1. A method for preparing a composite reverse osmosis membrane based on a diazanaphthone-structured polyarylene ether sulfone-based membrane, characterized in that, The steps are as follows: A blended ultrafiltration membrane of chloromethylated polyarylene ether sulfone and diazanaphthone-containing polyarylene ether sulfone was selected as the base membrane. A polyamine was dissolved in deionized water, and after complete dissolution, an aqueous phase additive was added to prepare an aqueous solution. The polyamine and the aqueous phase additive each accounted for 0.1–5% of the aqueous solution by mass. An acyl chloride monomer was dissolved in an alkane-based organic solvent to prepare an oil phase solution, with the acyl chloride monomer accounting for 0.01–5% of the oil phase solution by mass. Under ambient temperatures of 10–50 °C and humidity of 20–80%, the dried base membrane is immersed in an aqueous solution for 0.5–20 min to allow the base membrane to fully adsorb the aqueous solution, and for the polyamine in the aqueous solution to react with the chloromethyl groups on the surface of the base membrane. The base membrane is then removed and air-dried until excess aqueous solution is removed from the membrane surface. It is then placed in an organic solution for interfacial polymerization at 10–80 °C for 5–200 s. After polymerization, the membrane is removed and air-dried to obtain a nascent composite membrane. The nascent composite membrane is then post-treated at 20–120 °C for 0–60 min to obtain a composite reverse osmosis membrane based on a polyarylene ether sulfone base membrane containing a diazanaphthone structure. The composite reverse osmosis membrane based on a polyarylene ether sulfone membrane with a diazanaphthone structure uses a blend of chloromethylated polyarylene ether sulfone and polyarylene ether sulfone membrane with a diazanaphthone structure as the base membrane. The structural formula of chloromethylated polyarylether sulfone is: , or ; Where X is , or ; The structural formula of polyarylether sulfone containing a diazanaphthone structure is: ； Where Y is , or ; Among them, R1, R2, R3, and R4 are hydrogen atoms, halogen atoms, methyl groups, or aryl groups, and the four may be the same or different.

2. The preparation method according to claim 1, characterized in that, The ultrafiltration membrane blended with chloromethylated polyarylene ether sulfone and diazanaphthone-containing polyarylene ether sulfone is prepared by solution blending of chloromethylated polyarylene ether sulfone and diazanaphthone-containing polyarylene ether sulfone using a phase inversion method, wherein the mass ratio of chloromethylated polyarylene ether sulfone to diazanaphthone-containing polyarylene ether sulfone is 1:1 to 1:

50.

3. The preparation method according to claim 2, characterized in that, 1) Add additives and solvents to chloromethylated polyarylene ether sulfone and polyarylene ether sulfone containing diazanaphthone structure, mix and stir until completely dissolved to obtain a homogeneous and stable casting solution; wherein, the total mass of chloromethylated polyarylene ether sulfone and polyarylene ether sulfone containing diazanaphthone structure accounts for 5~30% of the mass fraction of the casting solution, the additive accounts for 0~30% of the mass fraction of the casting solution, and the solvent accounts for 40~95% of the mass fraction of the casting solution; 2) The membrane is scraped under the conditions of ambient temperature of 10~50 ℃ and humidity of 20~80%; after the solvent in the casting solution evaporates for 0~5 min, it is placed in a gel bath at a temperature of 0~50 ℃, and the additives in the gel bath account for 0~10 wt%. The membrane is gelled into an ultrafiltration membrane. The solvent and additives are washed away by soaking in water to obtain a blended ultrafiltration membrane of chloromethylated polyarylene ether sulfone and polyarylene ether sulfone containing diazanaphthone structure.

4. The preparation method according to claim 3, characterized in that, The additive is one or a mixture of two or more of ethylene glycol methyl ether, ethanol, ethylene glycol, glycerin, polyethylene glycol, and polyvinylpyrrolidone; The solvent is one or a mixture of two or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and dimethyl sulfoxide; The additives in the gel bath are one or more of the following: inorganic salts, organic solvents, acids, and bases. The inorganic salt is NaCl, LiCl, or CaCl2; the organic solvent is ethanol or isopropanol; the acid is HCl; and the base is NaOH.

5. The preparation method according to any one of claims 1-4, characterized in that, The polyamine is one or a mixture of two or more of the following: m-phenylenediamine, p-phenylenediamine, benzidine, and pyromellitic triamine.

6. The preparation method according to any one of claims 1-4, characterized in that, The aqueous phase additive is one or a mixture of two or more of the following: triethylamine, sodium carbonate, sodium dodecyl sulfate, Tween-80, and camphor sulfonic acid.

7. The preparation method according to any one of claims 1-4, characterized in that, The acyl chloride monomer is one or a mixture of two or more of isophthaloyl chloride, terephthaloyl chloride, trimesoyl chloride, and pyromellitic tetrachloroyl chloride.

8. The preparation method according to any one of claims 1-4, characterized in that, The alkane organic solvent is one or a mixture of two or more of n-hexane, cyclohexane, n-heptane, n-decane, and isoalkanes.

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