Furanyl composite nanofiltration membrane, preparation method and application thereof

Abstract

The application discloses a furan-based composite nanofiltration membrane and a preparation method and application thereof, and belongs to the technical field of membrane separation, wherein the furan-based composite nanofiltration membrane comprises a support base film and a polyamide separation layer constructed on the support base film; the polyamide separation layer is obtained by polycondensation of acyl chloride monomers and amine monomers on the support base film; the amine monomers comprise furan amine monomers and benzene ring amine monomers. The furan-based composite nanofiltration membrane provided by the application realizes the synchronous optimization of permeability and high flux by constructing a blending system of the furan amine monomers and the benzene ring amine monomers and utilizing the synergistic effect between the oxygen-containing heterocyclic structure of the furan ring and the hydrophobic rigid skeleton of the benzene ring; the furan-based composite nanofiltration membrane has high membrane flux, excellent permeability and high rejection rate for pollutants.

Description

Technical Field

[0001] This invention relates to the field of membrane separation technology, specifically to a furan-based composite nanofiltration membrane, its preparation method, and its application. Background Technology

[0002] With the continuous updating of raw materials for industrial products, the composition of pollutants in drinking water is becoming increasingly complex. Nanofiltration membranes are an effective method for removing pollutants, thus placing higher demands on existing nanofiltration membrane materials in terms of structure and performance. Polyamide thin-layer composite membranes are currently the mainstream material for preparing nanofiltration membranes due to their advantages such as simple preparation, high selectivity, and high mechanical strength.

[0003] Interfacial polymerization, with its unique reaction site and efficient and robust properties, is a widely used method for synthesizing various functional polymers. Interfacial polymerization typically involves dissolving amine monomers in water and acyl chloride monomers in an organic solvent, allowing the two monomers to polymerize at the organic solvent-water interface to synthesize cross-linked polyamide nanofilms. However, conventional organic solvent-water systems use water-soluble amine monomers, meaning that many non-water-soluble amine monomers with unique molecular structures and physicochemical properties cannot be used in the preparation of polyamide nanofilms, which limits the development of nanofiltration membranes with specific functions.

[0004] As an oxygen-containing five-membered heterocycle, the furan ring's electron-rich structure not only provides a certain degree of rigid support but also enhances the hydrogen bond interaction with water molecules through oxygen atoms, reducing transmembrane resistance. It is an ideal structural unit for constructing nanofiltration membranes with high permeability and solvent resistance.

[0005] In the prior art, patent CN118615880A provides a furan-based bio-based composite nanofiltration membrane, its preparation method, and its application; the furan-based small molecule monomer is selected from at least one of 2,5-diaminofuran, 2,5-diaminomethylfuran, 2,5-dihydroxymethylfuran, and 2,5-dihydroxymethyltetrahydrofuran, which is dissolved in an aqueous phase and reacted with an organic solvent containing acyl chloride monomers to prepare the nanofiltration membrane; the amine monomers used in this patent are all furan-structured amine monomers. Patent CN119034505A provides a method for preparing a composite nanofiltration membrane; the amine monomers include water-soluble monomers such as glutamic acid, iminodiacetic acid, and piperazine, which are reacted with an organic solvent containing acyl chloride monomers to prepare the composite nanofiltration membrane. References Nat Commun 16, 8414 (2025) utilize 4,4'-diaminodiphenyl ether (ODA), a benzene ring monomer, as an amine monomer. This monomer is poorly soluble in water. It is dissolved in a mixed solvent of choline chloride and ethylene glycol for interfacial polymerization to prepare polyamide nanofiltration membranes. Reference Angew. Chem. Int. Ed. 2024, 63, e202405891 utilizes 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (6FAP), a benzene ring monomer, as an amine monomer. This monomer is poorly soluble in water. It is dissolved in an ethanol-water mixed solvent for interfacial polymerization to prepare polyamide nanofiltration membranes.

[0006] In summary, most nanofiltration membranes prepared using interfacial polymerization in existing technologies are organic solvent-water systems, requiring highly water-soluble amine monomers. This limits the use of many non-water-soluble or poorly soluble amine monomers with unique molecular structures and physicochemical properties in the preparation of polyamide nanofilms. Furthermore, existing amine monomers used to construct the rigid framework of nanofiltration membranes are mainly limited to single-component systems, i.e., all using benzene-cyclic amine monomers or all using furan-cyclic amine monomers for interfacial polymerization, making it difficult to simultaneously optimize permeability and selectivity. Summary of the Invention

[0007] The purpose of this invention is to provide a furan-based composite nanofiltration membrane, its preparation method, and its application, in order to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A furan-based composite nanofiltration membrane includes a supporting base membrane and a polyamide separation layer constructed on the supporting base membrane; the polyamide separation layer is obtained by polycondensation of acyl chloride monomers and amine monomers on the supporting base membrane; the amine monomers include furan amine monomers and benzene ring amine monomers.

[0010] Furthermore, the furanamine monomer is selected from furanamine compound-1 and / or furanamine compound-2;

[0011] The structural formula of furanamine compound-1 is:

[0012] ;

[0013] The structural formula of furanamine compound-2 is:

[0014] .

[0015] Furthermore, the benzene ring amine monomer is selected from at least one of 4,4'-diaminodiphenyl ether, 2,2-bis(4-aminophenyl)propane, 9,9-bis(4-amino-3-tolyl)fluorene, tetra(4-aminophenyl)methane, and 2,2-bis(4-aminophenyl)hexafluoropropane.

[0016] Furthermore, the supporting substrate film is any one of polysulfone, polyethersulfone, polyvinylidene fluoride, and polyvinyl chloride.

[0017] Furthermore, the acyl chloride monomer is selected from at least one of pyromellitic methyl methacrylate (PMMA), terephthaloyl chloride (TBM), isophthaloyl chloride (IMMA), and adipoyl chloride (ADH).

[0018] Furthermore, the mass ratio of the furanamine monomer to the benzene ring amine monomer is (1-7):(7-1).

[0019] Another object of the present invention is to provide a method for preparing the above-mentioned furan-based composite nanofiltration membrane, which includes the following steps:

[0020] Furan amine monomers and benzene ring amine monomers are dissolved in a mixed solvent to obtain an aqueous solution;

[0021] The acyl chloride monomer is dissolved in a hydrocarbon solvent to obtain an organic phase solution;

[0022] An aqueous solution is applied to a supporting membrane, which is then drained. An organic solution is then applied to the supporting membrane to carry out an interfacial polymerization reaction, forming a polyamide separation layer. Finally, a thermal crosslinking treatment is performed to obtain a furan-based composite nanofiltration membrane.

[0023] Furthermore, the mixed solvent is a mixture of water and an ionic liquid; the ionic liquid is selected from at least one of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, and 1-decyl-3-methylimidazolium chloride; the hydrocarbon solvent is selected from at least one of n-hexane, cyclohexane, and heptane.

[0024] Another object of the present invention is to provide an application of the above-mentioned furan-based composite nanofiltration membrane in the removal of micro-pollutants.

[0025] Furthermore, the micro-contaminant is an antibiotic; the antibiotic includes tetracycline hydrochloride.

[0026] The present invention provides a furan-based composite nanofiltration membrane, which achieves simultaneous optimization of permeability and high flux by constructing a blend system of furan amine monomers and benzene ring amine monomers and utilizing the synergistic effect between the oxygen-containing heterocyclic structure of furan rings and the hydrophobic rigid framework of benzene rings. The furan-based composite nanofiltration membrane has high membrane flux, excellent permeability, and a high rejection rate for pollutants. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] In one embodiment of the present invention, a furan-based composite nanofiltration membrane is provided, which is composed of a supporting base membrane and a polyamide separation layer constructed on the supporting base membrane; wherein, the polyamide separation layer is obtained by polycondensation of acyl chloride monomer and amine monomer on the supporting base membrane; the amine monomer is a mixed system of furan amine monomer and benzene ring amine monomer.

[0029] Specifically, the preparation method of the furan-based composite nanofiltration membrane includes the following steps:

[0030] S1. Dissolve furanamine monomers and benzene ring amine monomers in a mixed solvent to obtain an aqueous solution; dissolve acyl chloride monomers in a hydrocarbon solvent to obtain an organic solution; the mass ratio of furanamine monomers to benzene ring amine monomers is (1-7):(7-1), preferably (3-5):1.

[0031] S2. At 20-30℃, apply the aqueous solution to the supporting substrate membrane, soak for 5-15 minutes and drain. Then apply the organic solution to the supporting substrate membrane and carry out interfacial polymerization reaction for 30-200 seconds to form a polyamide separation layer.

[0032] S3. Heat the polyamide separation layer and the supporting base membrane obtained above to 60-90℃ (preferably 60-75℃) for thermal crosslinking treatment for 5-60 minutes to obtain furan-based composite nanofiltration membrane.

[0033] In this embodiment of the invention, by employing a mixed solvent system, non-water-soluble amine monomers can also be used to prepare nanofiltration membranes via interfacial polymerization, thus overcoming the limitation of traditional nanofiltration membranes being only applicable to aqueous phases or single solvents.

[0034] In practical applications, the mixed solvent is a mixture of water and an ionic liquid; the volume percentage of the ionic liquid in the mixed solvent is 30%-85%; the ionic liquid is selected from at least one of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6), 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4), and 1-decyl-3-methylimidazolium chloride; the total concentration of amine monomers in the organic phase solution is 0.03wt%-0.5wt%, preferably 0.15-0.25%.

[0035] The hydrocarbon solvent is selected from at least one of n-hexane, cyclohexane, and heptane; the concentration of the acyl chloride monomer in the organic phase solution is 0.02wt%-0.4wt%; the acyl chloride monomer is selected from at least one of trimesoyl chloride, terephthaloyl chloride, isophthaloyl chloride, and adipyl chloride.

[0036] The benzene ring amine monomers are selected from at least one of 4,4'-diaminodiphenyl ether (ODA), 2,2-bis(4-aminophenyl)propane (BAP), 9,9-bis(4-amino-3-tolyl)fluorene, tetra(4-aminophenyl)methane (TAM), and 2,2-bis(4-aminophenyl)hexafluoropropane.

[0037] The supporting base film is any one of polysulfone, polyethersulfone, polyvinylidene fluoride, and polyvinyl chloride.

[0038] The acyl chloride monomer is selected from at least one of pyromellitic methyl methacrylate, terephthaloyl chloride, isophthaloyl chloride and adipyl chloride.

[0039] The furanamine monomers are selected from furanamine compound-1 and / or furanamine compound-2;

[0040] The structural formula of furanamine compound-1 is:

[0041] ;

[0042] Specifically, the synthesis method of furanamine compound-1 is as follows: Under a nitrogen atmosphere, 2,8-dibromodibenzofuran (1 eq) and (5-(hydroxymethyl)furan-2-yl)boronic acid (2.3 eq) were cross-coupled via a palladium catalyst (Pd(PPh3)2Cl2, 0.0025 eq) and a base (potassium carbonate, 2.5 eq) to construct a hydroxymethyl intermediate. Then, under alkaline conditions of triethylamine in an ice bath (3 eq), the hydroxymethyl intermediate (1 eq) underwent a substitution reaction with methanesulfonyl chloride (2.4 eq) for 2 h to convert the hydroxyl group to a methanesulfonate intermediate. The methanesulfonate intermediate was further azidated with sodium azide (3.0 eq) at 60 °C for 8 h to obtain an azide product. Finally, under the catalysis of palladium on carbon (10% Pd / C, 10 wt%), a catalytic hydrogenation reduction reaction was carried out using hydrogen to obtain furanamine compound-1.

[0043] The structural formula of furanamine compound-2 is:

[0044] ;

[0045] Specifically, the synthesis method of furanamine compound-2 is as follows: under a nitrogen atmosphere, p-phenylenediamine (1 eq), 2,5-furandiethanol (2.2 eq), and potassium tert-butoxide (2.4 eq) are dissolved in diethylene glycol dimethyl ether and reacted at 70°C for 48 h in the presence of an iridium catalyst ([IrOMe(cod)]2, 0.03 eq) to obtain an intermediate containing a furanethanol structure; referring to the synthesis method of furanamine compound-1 above, the intermediate containing a furanethanol structure is converted into a methanesulfonate ester by methanesulfonyl chloride substitution, and then reacted with sodium azide to obtain an azide product, which is finally reduced by hydrogenation under palladium on carbon catalysis to obtain furanamine compound-2.

[0046] In another embodiment of the present invention, the application of the above-described furanyl composite nanofiltration membrane in the removal of micro-pollutants is also provided. Specifically, the micro-pollutants are antibiotics; antibiotics include, but are not limited to, tetracycline hydrochloride.

[0047] It should be noted that all raw materials used above are commercially available products and are used directly without further purification. The following examples are cases of the present invention in practical application and are only illustrative and not limited thereto.

[0048] Example 1: This example provides a method for preparing a furan-based composite nanofiltration membrane, comprising the following steps:

[0049] S1. Furanamine-type compounds -2 and 4,4'-diaminodiphenyl ether monomers were dissolved in a mixed solvent of 1-butyl-3-methylimidazolium tetrafluoroborate and water at a mass ratio of 3:1 (1-butyl-3-methylimidazolium tetrafluoroborate was 65% by volume) to obtain an aqueous solution with a total monomer concentration of 0.4 wt%. Tristyrene chloride was dissolved in n-hexane to prepare an organic phase solution with a tristyrene chloride concentration of 0.2 wt%.

[0050] S2. At room temperature, the above aqueous solution is applied to the polyethersulfone support film, soaked for 8 minutes and drained, and then the above organic solution is applied to the polyethersulfone support film to carry out interfacial polymerization reaction for 60 seconds to form a polyamide separation layer.

[0051] S3. Heat the polyamide separation layer and polyethersulfone support base membrane obtained above to 60°C for thermal crosslinking treatment for 10 minutes to obtain furan-based composite nanofiltration membrane.

[0052] Example 2: This example provides a method for preparing a furan-based composite nanofiltration membrane, comprising the following steps:

[0053] S1. Furanamine-type compounds -2 and 4,4'-diaminodiphenyl ether monomers were dissolved in a mixed solvent of 1-butyl-3-methylimidazolium tetrafluoroborate and water at a mass ratio of 5:1 (1-butyl-3-methylimidazolium tetrafluoroborate was 65% by volume) to obtain an aqueous solution with a total monomer concentration of 0.4 wt%. Tristyrene chloride was dissolved in n-hexane to prepare an organic phase solution with a tristyrene chloride concentration of 0.2 wt%.

[0054] S2. At room temperature, the above aqueous solution is applied to the polyethersulfone support film, soaked for 8 minutes and drained, and then the above organic solution is applied to the polyethersulfone support film to carry out interfacial polymerization reaction for 60 seconds to form a polyamide separation layer.

[0055] S3. Heat the polyamide separation layer and polyethersulfone support base membrane obtained above to 60°C for thermal crosslinking treatment for 10 minutes to obtain furan-based composite nanofiltration membrane.

[0056] Example 3: This example provides a method for preparing a furan-based composite nanofiltration membrane, comprising the following steps:

[0057] S1. Furanamine-type compounds -2 and 4,4'-diaminodiphenyl ether monomers were dissolved in a mixed solvent of 1-butyl-3-methylimidazolium tetrafluoroborate and water at a mass ratio of 1:5 (the volume percentage of 1-butyl-3-methylimidazolium tetrafluoroborate was 65%) to obtain an aqueous solution with a total monomer concentration of 0.4 wt%. Tristyrene chloride was dissolved in n-hexane to prepare an organic phase solution with a concentration of 0.2 wt%.

[0058] S2. At room temperature, the above aqueous solution is applied to the polyethersulfone support film, soaked for 8 minutes and drained, and then the above organic solution is applied to the polyethersulfone support film to carry out interfacial polymerization reaction for 60 seconds to form a polyamide separation layer.

[0059] S3. Heat the polyamide separation layer and polyethersulfone support base membrane obtained above to 60°C for thermal crosslinking treatment for 10 minutes to obtain furan-based composite nanofiltration membrane.

[0060] Example 4: This example provides a method for preparing a furan-based composite nanofiltration membrane, comprising the following steps:

[0061] S1. Furanamine compound-1 and 9,9-bis(4-amino-3-tolyl)fluorene monomers were dissolved in a mixed solvent of 1-ethyl-3-methylimidazolium tetrafluoroborate and water at a mass ratio of 4:1 (1-ethyl-3-methylimidazolium tetrafluoroborate was 75% by volume) to obtain an aqueous solution with a total monomer concentration of 0.25 wt%. Terephthaloyl chloride was dissolved in n-hexane to prepare an organic phase solution with a pyromellitic acid trimethylol chloride concentration of 0.15 wt%.

[0062] S2. At room temperature, the above aqueous solution is applied to the polysulfone support film, soaked for 10 min and drained, and then the above organic solution is applied to the polysulfone support film to carry out interfacial polymerization reaction for 45 s to form a polyamide separation layer.

[0063] S3. Heat the polyamide separation layer and polysulfone support membrane obtained above to 65°C for thermal crosslinking treatment for 10 minutes to obtain furan-based composite nanofiltration membrane.

[0064] Example 5: This example provides a method for preparing a furan-based composite nanofiltration membrane, comprising the following steps:

[0065] S1. Furanamine compound-1 and 2,2-bis(4-aminophenyl)propane monomer were dissolved in a mixed solvent of 1-ethyl-3-methylimidazolium tetrafluoroborate and water at a mass ratio of 3:1 (1-ethyl-3-methylimidazolium tetrafluoroborate was 35% by volume) to obtain an aqueous solution with a total monomer concentration of 0.25 wt%. Terephthaloyl chloride was dissolved in n-hexane to prepare an organic phase solution with a pyromellitic acid trimethylol chloride concentration of 0.15 wt%.

[0066] S2. At room temperature, the above aqueous solution is applied to the polysulfone support film, soaked for 10 min and drained, and then the above organic solution is applied to the polysulfone support film to carry out interfacial polymerization reaction for 45 s to form a polyamide separation layer.

[0067] S3. Heat the polyamide separation layer and polysulfone support membrane obtained above to 65°C for thermal crosslinking treatment for 10 minutes to obtain furan-based composite nanofiltration membrane.

[0068] Comparative Example 1: This comparative example provides a method for preparing a nanofiltration membrane, comprising the following steps:

[0069] S1. Dissolve 4,4'-diaminodiphenyl ether monomer in a mixed solvent of 1-butyl-3-methylimidazolium tetrafluoroborate and water (1-butyl-3-methylimidazolium tetrafluoroborate is 65% by volume) to obtain an aqueous solution with a total monomer concentration of 0.4 wt%; dissolve trimesoyl chloride in n-hexane to prepare an organic solution with a trimesoyl chloride concentration of 0.2 wt%.

[0070] S2. At room temperature, the above aqueous solution is applied to the polyethersulfone support film, soaked for 8 minutes and drained, and then the above organic solution is applied to the polyethersulfone support film to carry out interfacial polymerization reaction for 60 seconds to form a polyamide separation layer.

[0071] S3. Heat the polyamide separation layer and polyethersulfone support base membrane obtained above to 60°C for thermal crosslinking treatment for 10 minutes to obtain nanofiltration membrane.

[0072] Comparative Example 2: This comparative example provides a method for preparing a nanofiltration membrane, comprising the following steps:

[0073] S1. Dissolve furanamine compound-2 and 4,4'-diaminodiphenyl ether monomer in water at a mass ratio of 3:1 to obtain an aqueous solution with a total monomer concentration of 0.4 wt%; dissolve trimesoyl chloride in n-hexane to prepare an organic solution with a trimesoyl chloride concentration of 0.2 wt%.

[0074] S2. At room temperature, the above aqueous solution is applied to the polyethersulfone support film, soaked for 8 minutes and drained, and then the above organic solution is applied to the polyethersulfone support film to carry out interfacial polymerization reaction for 60 seconds to form a polyamide separation layer.

[0075] S3. Heat the polyamide separation layer and polyethersulfone support base membrane obtained above to 60°C for thermal crosslinking treatment for 10 minutes to obtain the composite nanofiltration membrane.

[0076] Comparative Example 3: This comparative example provides a method for preparing a nanofiltration membrane, comprising the following steps:

[0077] S1. Dissolve furanamine compound-1 in a mixed solvent of 1-ethyl-3-methylimidazolium tetrafluoroborate and water (1-ethyl-3-methylimidazolium tetrafluoroborate is 75% by volume) to obtain an aqueous solution with a total monomer concentration of 0.25 wt%; dissolve terephthaloyl chloride in n-hexane to prepare an organic solution with a pyromellitic acid trimethylol chloride concentration of 0.15 wt%.

[0078] S2. At room temperature, the above aqueous solution is applied to the polysulfone support film, soaked for 10 min and drained, and then the above organic solution is applied to the polysulfone support film to carry out interfacial polymerization reaction for 45 s to form a polyamide separation layer.

[0079] S3. Heat the polyamide separation layer and polysulfone support base membrane obtained above to 65°C for thermal crosslinking treatment for 10 minutes to obtain nanofiltration membrane.

[0080] Performance testing: The nanofiltration membranes prepared in Examples 1-5 and Comparative Examples 1-3 were fixed in a cross-flow filtration test device for testing. Specifically, pure water was passed through the cross-flow filtration test device in internal pressure mode, and the pressure was set at 0.30 MPa for 20 min. After the membrane was stably pressed, the water obtained within 15 min was collected, and the pure water flux was tested by weighing method. A tetracycline hydrochloride solution with a concentration of 10 mg / L was used as the feed liquid, and the permeation flux and separation performance (removal rate of pollutants) of the nanofiltration membrane were tested at 0.30 MPa. The results are shown in Table 1.

[0081] Table 1

[0082]

[0083] As shown in Table 1, by comparing the examples and comparative examples, the permeation flux of the nanofiltration membrane gradually increases with the increase of the amount of furanylamine monomers added. The synergistic effect of furanylamine monomers and rigid benzene rings not only constructs more suitable microporous channels but also reduces the transport resistance of water molecules, thus improving permeation and achieving good retention of pollutants. Furthermore, by adjusting the feeding ratio of furanylamine monomers to benzene ring amine monomers, the permeation selectivity of the present invention can be controlled on demand to meet the application requirements of different separation scenarios. At the same time, furan-based materials also possess the advantages of green and sustainable development, indicating that the furan-based composite nanofiltration membrane provided by the present invention has broad application prospects.

[0084] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification.

Claims

1. A furan-based composite nanofiltration membrane, characterized in that, It includes a supporting base membrane and a polyamide separation layer constructed on the supporting base membrane; the polyamide separation layer is obtained by polycondensation of acyl chloride monomers and amine monomers on the supporting base membrane; the amine monomers include furan amine monomers and benzene ring amine monomers; The furanamine monomer is selected from furanamine compound-1 and / or furanamine compound-2; The structural formula of furanamine compound-1 is: ； The structural formula of furanamine compound-2 is: ； The benzene ring amine monomer is selected from at least one of 4,4'-diaminodiphenyl ether, 2,2-bis(4-aminophenyl)propane, 9,9-bis(4-amino-3-tolyl)fluorene, tetra(4-aminophenyl)methane and 2,2-bis(4-aminophenyl)hexafluoropropane; The mass ratio of furanamine monomers to benzene ring amine monomers is (1-7):(7-1); The preparation method of the furan-based composite nanofiltration membrane includes the following steps: Furan amine monomers and benzene ring amine monomers are dissolved in a mixed solvent to obtain an aqueous solution; The acyl chloride monomer is dissolved in a hydrocarbon solvent to obtain an organic phase solution; An aqueous solution was applied to the supporting membrane, and after wetting and draining, an organic solution was applied to the supporting membrane to carry out an interfacial polymerization reaction to form a polyamide separation layer. Then, a thermal crosslinking treatment was performed to obtain a furan-based composite nanofiltration membrane. The mixed solvent is a mixture of water and an ionic liquid; the ionic liquid is selected from at least one of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate and 1-decyl-3-methylimidazolium chloride; the hydrocarbon solvent is selected from at least one of n-hexane, cyclohexane and heptane.

2. The furan-based composite nanofiltration membrane according to claim 1, characterized in that, The supporting substrate film is any one of polysulfone, polyethersulfone, polyvinylidene fluoride, and polyvinyl chloride.

3. The furan-based composite nanofiltration membrane according to claim 1, characterized in that, The acyl chloride monomer is selected from at least one of pyromellitic methyl methacrylate, terephthaloyl chloride, isophthaloyl chloride, and adipyl chloride.

4. The application of a furan-based composite nanofiltration membrane as described in any one of claims 1-3 in the removal of micro-pollutants.

5. The application according to claim 4, characterized in that, The micro-contaminant is an antibiotic; the antibiotic includes tetracycline hydrochloride.

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