Amino acid functionalized MOF-based mixed matrix membranes and methods of making the same

Abstract

This invention belongs to the field of membrane preparation and application technology, and discloses an amino acid-functionalized MOF-based hybrid matrix membrane and its preparation method. The preparation steps are as follows: using amino acid-functionalized MOF material as inorganic filler and polymer as matrix material, amino acids are introduced into the MOF backbone through ligand modification to achieve functionalization modification. Then, the amino acid-functionalized MOF filler and polymer matrix are blended to obtain an amino acid-functionalized MOF-based hybrid matrix membrane. This invention introduces active sites such as amino and carboxyl groups into the MOF backbone through amino acid functionalization, while optimizing the interfacial compatibility between MOF and polymer matrix and reducing the formation of non-selective voids. It can achieve size recognition of propylene and propane by utilizing the microporous sieving effect of MOF material, and enhance separation selectivity through the specific interaction between amino acid active sites and propylene molecules, significantly improving the propylene / propane separation performance of the membrane, especially propylene permeability.

Description

Technical Field

[0001] This invention belongs to the field of membrane preparation and application technology, and discloses an amino acid functionalized MOF-based hybrid matrix membrane and its preparation method. Background Technology

[0002] Propylene is one of the most important intermediate products in the petrochemical industry, mainly used in the production of polypropylene, acrylonitrile, isopropanol, propylene oxide, and propylene derivatives. Propylene is primarily derived from processes such as catalytic cracking, steam cracking, propane dehydrogenation, and methanol-to-olefins. These processes typically only yield a mixture of propylene and propane. Therefore, efficient separation of propylene and propane is crucial for obtaining high-purity polymer-grade propylene. However, due to the very similar physical properties (boiling point, polarizability, molecular size) of propylene and propane, their separation is a highly energy-intensive process. Membrane separation offers significant advantages in propylene / propane separation, including low energy consumption, small footprint, and sustainable operation. Traditional polymer membranes suffer from the trade-off effect, failing to simultaneously achieve high permeability and high selectivity. Hybrid matrix membranes, prepared using polymers as the matrix and MOFs as the filler, combine the easy processability of polymers with the excellent separation performance of MOFs, thus overcoming the trade-off effect and becoming a potentially superior membrane material for propylene / propane separation.

[0003] ZIF-8-based hybrid matrix membranes have recently become representative materials for separating propylene / propane. Theoretically, ZIF-8 has a six-membered pore window diameter of 0.34 nm. However, Li et al. investigated the adsorption isotherms and kinetics of propylene and propane in ZIF-8 crystals. They found that propylene and propane molecules with molecular sizes larger than 3.4 Å can enter the pores of ZIF-8, and the effective pore size of ZIF-8 is between 4.0 and 4.2 Å, falling between the molecular diameters of propylene and propane. Furthermore, the diffusion rate coefficient of propylene can reach more than 100 times that of propane (D...). 丙烯 / D 丙烷 = 125), which indicates that the ZIF-8 membrane has good application prospects in the separation of propylene and propane.

[0004] To improve the separation performance of ZIF-8-based hybrid matrix membranes, functional modification of ZIF-8 can be performed by introducing functional groups (-NH2, -COOH, -SH, -OH) into the ZIF-8 framework through ligand exchange, thereby regulating the surface chemical properties and pore structure. (e.g., Zhang X, Hai G, Yao Y, et al. Enhanced Propylene / Propane Separation via Aniline-Decorated ZIF-8 Membrane: Lattice Rigidity Adjustment and Adsorption Site Introduction [J]. Angewandte Chemie International Edition, 2024, 63(49): e202411440) and adjusting the separation performance by changing the ratio of functionalized ligands (e.g., Song EY, Wei KF, Lian HQ, et al. Improved propylene / propane separation performance under high temperature and pressures on in-situ ligand-doped ZIF-8 membranes [J]. Journal of Membrane Science, 2021, 617: 10.). Amino acids are typical amphiphilic molecules, and their molecular structure contains hydrophilic -NH2 and -COOH functional groups, which can react with unsaturated Zn on the ZIF-8 surface. 2+ Coordination repair of surface ligand deficiency defects occurs, while hydrophilic groups can coat the ZIF-8 surface, effectively inhibiting water molecule erosion of defect sites and significantly improving chemical stability. Furthermore, amino acids can utilize the C=C double bond of propylene to generate π-π interactions, achieving selective and preferential adsorption of propylene molecules, thereby improving the propylene / propane separation performance of the mixed matrix membrane. Simultaneously, the hydrophobic alkyl side chains of amino acids can induce a regular and orderly arrangement of polymer segments, alleviating the aggregation of ZIF-8 filler in the polymer matrix and optimizing the interfacial compatibility between the filler and the polymer. Moreover, the hydrophilic-hydrophobic balance of the ZIF-8 surface can be precisely controlled, further improving the hydrothermal stability of ZIF-8.

[0005] Amino acids are naturally low in toxicity, exhibit excellent biocompatibility, and are completely biodegradable. Their modification reactions are mild, requiring no high-temperature heating or high-boiling-point organic solvents, offering advantages such as low toxicity, low cost, and environmental friendliness. In terms of applications, amino acid-functionalized MOFs can be used for targeted drug delivery in the biopharmaceutical field; in environmental engineering, they can be used to prepare highly efficient adsorbents to remove heavy metal ions and organic pollutants, achieving water purification; and they also have significant application value in cutting-edge fields such as chiral chromatographic separation and asymmetric catalysis. However, current research and applications of amino acid-functionalized modified MOFs are mainly concentrated in biopharmaceuticals, environmental remediation, and chiral separation, while research and practical applications in gas separation remain very limited.

[0006] Therefore, this invention aims to prepare amino acid-functionalized MOFs for propylene / propane separation via de novo synthesis. This modification reaction only requires room temperature conditions, does not require high-boiling-point organic solvents, and is environmentally friendly and low in toxicity. It enables the control of the chemical environment within the pores and the hydrophilicity / hydrophobicity of the surface. Utilizing the hydrogen bonding and dipole interactions between amino acid functional groups and specific gases, the selective adsorption and sieving effect of propylene is enhanced. Furthermore, a mixed matrix membrane is prepared using polyimide as the polymer matrix, which significantly inhibits filler aggregation, improves interfacial interactions, and enhances the separation performance of the mixed matrix membrane. The amino acid-functionalized MOF-based mixed matrix membrane prepared by this invention exhibits excellent separation performance for propylene / propane. Summary of the Invention

[0007] This invention proposes an amino acid-functionalized MOF-based hybrid matrix membrane and its preparation method.

[0008] The technical solution of this invention: An amino acid-functionalized MOF-based hybrid matrix membrane is disclosed. Using polyimide as a precursor polymer, MOFs with different amino acid functionalization ratios are prepared via de novo synthesis. The polyimide and MOFs are then physically blended to form the membrane. The resulting hybrid matrix membrane exhibits excellent propylene / propane separation performance. The structures of the amino acids, MOFs, and polyimide are as follows: .

[0009] A method for preparing an amino acid-functionalized MOF-based hybrid matrix membrane includes the following steps: (1) Synthesis of polyimide precursor; Where m and n are the degrees of polymerization of polyimide, m and n = 100-500, and are positive integers; Polyimide precursors are formed by the condensation polymerization of dianhydride monomers and diamine monomers; The dianhydride monomer A is any one of hexafluorodianhydride (6FDA), 4,4'-oxydiphthalic anhydride (OPDA), and 2,3,3',4'-biphenyltetracarboxylic dianhydride (BPDA): ; The diamine monomer B is any one of 2,3,5,6-tetramethyl-1,4-phenylenediamine (Durene), 2,4,6-trimethyl-1,3-phenylenediamine (DAM), and 1,3-phenylenediamine (mPDA): ; The diamine monomer C is any one of the following diamine structures: 3,5-diaminobenzoic acid (DABA), 2,2-bis(4-aminophenyl)hexafluoropropane (6FpDA), and 4,4'-diaminodiphenyl ether (ODA). .

[0010] Under nitrogen protection and an ice-water bath, a mixture of diamine monomers B and C, or any one of diamine monomers B and C, is added to solvent D and stirred continuously until completely dissolved. Then, dianhydride monomer A is added to obtain a solution with a mass fraction of 10–25 wt.%. After reacting for 3 h, the ice-water bath is removed, and the reaction continues at room temperature for 24 h. Catalyst E and dehydrating agent F are then added to the reaction system, and the reaction continues at room temperature for another 24 h. The product is poured into methanol to obtain a filamentous precipitate, which is washed several times with methanol and then vacuum dried at 60–150 °C to finally obtain the polyimide precursor.

[0011] Solvent D is one of anhydrous NMP, m-cresol, and DAMC; Catalyst E is triethylamine or pyridine; Dehydrating agent F is acetic anhydride; The molar ratio of diamine monomer to dianhydride monomer A is 1:1; The molar ratio of diamine monomer, catalyst E and dehydrating agent F is 1:1:4.

[0012] (2) Synthesizing amino acid-functionalized MOFs; Metal salt A was added to solvent B to obtain a metal salt A solution. The amino acid ligand, 2-methylimidazole, and basicity regulator C were added to solvents B and E and dissolved by stirring at room temperature to obtain an imidazole solution. The metal salt A solution was quickly poured into the imidazole solution to allow for complete ligand exchange. After the reaction was complete, the white suspension was centrifuged and washed repeatedly with methanol. The washed product was dried in a vacuum oven to obtain a white powder. The amino acid ligand is L-proline (L-Pro), L-histidine (L-His), L-tyrosine (L-Tyr), L-phenylalanine (L-Phe), or L-tryptophan (L-Trp).

[0013] .

[0014] Metal salt A is one of zinc nitrate hexahydrate, zinc sulfate heptahydrate, and zinc acetate dihydrate; Alkalinity regulator C is one of sodium formate, 1-methylimidazole, or triethylamine; Solvent E is deionized water; Solvent B is methanol or ethanol; The volume ratio of solvent B to solvent E is 1-3:2; The molar ratio of metal salt A to 2-methylimidazole is 1:2-16; The molar ratio of alkaline regulator C to metal salt A is 1-8:1; The molar ratio of the amino acid ligand to 2-methylimidazole is 1:7-19; The exchange reaction takes 24-60 hours and is carried out at a temperature of 25°C. The centrifugation speed was 10,000 rpm, and the centrifugation time was 10 min; The drying temperature was 80℃, and the drying time was 24 hours. (3) Preparation of amino acid-functionalized MOF-based hybrid matrix membranes: The amino acid-functionalized MOF synthesized in step (3) was activated in a vacuum drying oven and ultrasonically dispersed in solvent A to obtain a MOF dispersion. The polyimide precursor synthesized in step (1) was then dispersed in solvent A to obtain a polyimide precursor solution. The MOF dispersion was added to the polyimide precursor solution in multiple batches through a 0.45 μm microporous membrane filter and ultrasonically stirred to mix evenly. Then, air bubbles in the casting solution were removed by ultrasonication. After standing for a period of time, the mixture was poured into a culture dish and placed in a vacuum oven to dry and form a film, thus obtaining an amino acid-functionalized MOF-based mixed matrix membrane.

[0015] Solvent A is N,N-dimethylformamide or N,N-dimethylacetamide; The polymer mass fraction in the casting solution is 1-20 wt%; The ultrasonic stirring time is 12-24 h, and the ultrasonication time is 20 min. The settling time is 2 hours; The evaporation temperature of the casting solution is 50℃, and the time is 12-24 h.

[0016] The beneficial effects of this invention are as follows: Compared with other mixed matrix membranes, this invention prepares a mixed matrix membrane by functionalizing MOFs with amino acids. Natural amino acids have no toxic side effects, possess good biocompatibility, and can be completely degraded in the natural environment. Amino acid functionalization modification is simple to operate and operates in a mild environment, avoiding the limitations of high-temperature heating and the use of high-boiling-point solvents, while also considering multiple advantages such as environmental safety, economic cost, and green environmental protection. The amphiphilic amino acid-functionalized MOFs possess both hydrophilic -NH2 and -COOH groups and hydrophobic alkyl side chains, enhancing the selective adsorption and sieving effect of propylene, while effectively improving the water stability and chemical stability of the MOF. The prepared mixed matrix membrane exhibits excellent propylene / propane separation performance. It has the advantages of simple preparation method and significant effects. Attached Figure Description

[0017] Figure 1 The amino acid functionalized in Example 3 was 30 wt.% L-His 12.5% SEM cross-sectional view of ZIF-8 MMM. Detailed Implementation

[0018] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and technical solutions. Gas separation performance test: The gas separation performance test method used in this invention is the constant volume pressure variation method, the test temperature is 35℃, and the test pressure is 65 psi.

[0019] Example 1: 10 wt.% L-His 12.5% Preparation of ZIF-8 / 6FDA-Durene MMM (L-histidine ligand ratio of 12.5%) (1) Amino acid functionalized L-His 12.5% Preparation of ZIF-8 (L-histidine ligand ratio 12.5%): 0.093 g L-His (L-histidine), 0.345 g 2-methylimidazole, and 50 μL triethylamine (TEA) were dissolved in a mixed solvent of 12 mL methanol and 8 mL deionized water to obtain an imidazole mixed solution. Then, 0.357 g Zn(NO3)2•6H2O was dissolved in 20 mL methanol, and this solution was poured into the imidazole mixed solution at room temperature and stirred continuously for 24 h. The reaction product was collected by centrifugation at 10000 rpm for 10 min to obtain the crude product, which was washed three times with methanol. After washing, the washed product was dried in a forced-air oven and then transferred to a vacuum oven at 80 °C for 12 h to obtain the synthesized white powder.

[0020] (2) Preparation of polymer 6FDA-Durene: Under nitrogen protection and ice bath conditions, 0.657 g of the diamine monomer Durene was dissolved in 12 ml of anhydrous NMP solution. After the system was completely dissolved, 1.777 g of the dianhydride monomer 6FDA was added. After reacting for 3 h, the ice bath was removed, and the reaction was continued at room temperature for 24 h to form polyamic acid. Then, acetic anhydride as a dehydrating agent and triethylamine as a catalyst were added to the polyamic acid solution, and the mixture was stirred for another 24 h to complete the chemical imidization. After the reaction was completed, the product was poured into methanol for multiple washes. After washing, it was placed in a vacuum oven and dried overnight to obtain the polyimide precursor.

[0021] (3) 10 wt.% L-His 12.5% Preparation of -ZIF-8 / 6FDA-Durene MMM: L-His 12.5% -ZIF-8 was activated in a vacuum drying oven. L-His was weighed. 12.5% 0.02 g of ZIF-8 powder was added to a glass bottle, and DMF was added and stirred to prepare a 5 g suspension. 0.18 g of the polymer was weighed and added to a glass bottle, and DMF was added to prepare a 5 g DMF solution. The above L-His... 12.5% - After the ZIF-8 DMF suspension and polymer DMF solution were magnetically stirred at room temperature for 24 h, the polymer DMF bath was filtered through a syringe with a 0.45-micron filter membrane and then slowly added to the stirred L-His solution. 12.5% The mixture was stirred and dispersed in ZIF-8 DMF suspension for 12 h to ensure homogeneity. The casting solution was then ultrasonically dispersed for 20 min to remove air bubbles. The mixture was poured into petri dishes and allowed to stand for a period of time. The petri dishes were then placed in a vacuum oven and dried for 24 h to form a film, yielding 10 wt.% L-His amino acid-functionalized film. 12.5% -ZIF-8 / 6FDA-Durene MMM.

[0022] Example 2: 20 wt.% L-His 12.5% -ZIF-8 / 6FDA-Durene MMM Preparation (1) Preparation of polymer 6FDA-Durene: The method is the same as step (1) in Example 1.

[0023] (2) Amino acid functionalized L-His 12.5% Preparation of ZIF-8: The method is the same as step (2) in Example 1.

[0024] (3) 20 wt.% L-His 12.5%Preparation of -ZIF-8 / 6FDA-Durene MMM: The amount of L-His-ZIF-8 used was 0.04 g, the amount of 6FDA-Durene used was 0.16 g, and the other methods were the same as step (3) in Example 1.

[0025] Example 3: 30wt.% L-His 12.5% -ZIF-8 / 6FDA-Durene MMM Preparation (1) Preparation of polymer 6FDA-Durene: The method is the same as step (1) in Example 1.

[0026] (2) Amino acid functionalized L-His 12.5% Preparation of ZIF-8: The method is the same as step (2) in Example 1.

[0027] (3) 30 wt.% L-His 12.5% Preparation of -ZIF-8 / 6FDA-Durene MMM: The amount of L-His-ZIF-8 used was 0.06 g, the amount of 6FDA-Durene used was 0.14 g, and the other methods were the same as step (3) in Example 1.

[0028] Comparative Example 1: Preparation of 10 wt.% ZIF-8 / 6FDA-Durene MMM without amino acid functionalization (1) Preparation of ZIF-8: 3.284 g of 2-methylimidazole and 2.975 g of zinc nitrate hexahydrate were dissolved in 50 ml of methanol respectively. The dissolved zinc nitrate solution was added to the imidazole solution, and the mixture was stirred at room temperature for 1 h. After the reaction, the corresponding reaction products were collected by centrifugation at 10000 rpm for 10 min and washed several times with methanol. The washed products were dried under vacuum at 80 °C overnight to obtain white ZIF-8 powder.

[0029] (2) Preparation of polymer 6FDA-Durene: The method is the same as step (2) in Example 1.

[0030] (3) Preparation of 10 wt.% ZIF-8 / 6FDA-Durene MMM without amino acid functionalization: The preparation steps of the mixed matrix membrane are exactly the same as those in Example 1. The amount of ZIF-8 is 0.02 g, the amount of 6FDA-Durene is 0.18 g, and the other methods are the same as steps (3) in Example 1.

[0031] Comparative Example 2: 10 wt.% L-His 5% Preparation of ZIF-8 / 6FDA-Durene MMM (L-histidine ligand ratio of 5%) (1) L-His 5% Preparation of -ZIF-8 (L-histidine ligand ratio of 10%): Except for the mixing of 2-methylimidazole (2-mIm) and L-histidine (L-His) at a molar ratio of 19:1 as the ligand, the remaining preparation steps are the same as those in Example 1 for L-His. 12.5% The preparation of -ZIF-8 is exactly the same.

[0032] (2) Preparation of polymer 6FDA-Durene: The method is the same as step (2) in Example 1.

[0033] (3) 10 wt.% L-His 5% -ZIF-8 / 6FDA-Durene MMM Preparation: The preparation steps for the mixed matrix membrane are exactly the same as in Example 1, L-His 5% The dosage of ZIF-8 was 0.02 g, the dosage of 6FDA-Durene was 0.18 g, and the other methods were the same as step (3) in Example 1.

[0034] The propylene-propane permeability and selectivity of the mixed matrix membranes prepared in Comparative Examples 1 and 2 and Examples 1-3 are shown in Table 1. Comparing the Comparative Examples and Examples, it can be found that Examples 1-3 exhibited superior propylene permeability at different filler loadings (10 wt%, 20 wt%, 30 wt%); and with L-His 12.5% -Increasing the loading of ZIF-8 filler in the membrane significantly improved the propylene permeability of the mixed matrix membrane. Comparative Example 1 and Example 1 used the same polyimide precursor and filler loading, only the filler was ZIF-8 and amino acid-functionalized L-His, respectively. 12.5% -ZIF-8. Performance results showed that the permeability and selectivity of the mixed matrix membrane in Comparative Example 1 were inferior to those in Example 1. This is because L-His amino acid functionalization modification can regulate the pore structure and surface polarity of ZIF-8, which improves both the permeability of the membrane material to propylene and the interfacial compatibility between the filler and the polyimide precursor, thereby improving the propylene / propane selectivity. Comparative Example 2 used the same polymer and filler loading as Example 1, only using L-His-ZIF-8 with different L-His doping ratios (5% and 12.5%). The comparison revealed that the separation performance of Comparative Example 2 was also inferior to that of Example 1. This is because when the L-His doping ratio is low, the number of L-His functional groups (–COOH, –NH2) is small, resulting in weaker specific selective adsorption of propylene molecules and limited improvement in the propylene / propane separation performance of the mixed matrix membrane. In summary, amino acid functionalized L-His... 12.5%-ZIF-8 / 6FDA-Durene MMM can effectively improve the permeability of mixed matrix membranes to propylene and the selectivity of propylene / propane separation, while unmodified ZIF-8 or L-His with low amino acid doping ratio can improve the permeability of mixed matrix membranes to propylene and the selectivity of propylene / propane separation. 5% Neither ZIF-8 nor any of them could achieve the optimal separation effect, further verifying the rationality and superiority of the technical solution of the present invention.

[0035] Table 1 shows the propylene / propane permeability and selectivity of the mixed matrix membranes prepared in the control example and the examples.

Claims

1. An amino acid-functionalized MOF-based hybrid matrix membrane, characterized in that, The structure of the amino acid-functionalized MOF-based hybrid matrix membrane is as follows: ； Where m and n are the degrees of polymerization of polyimide, m and n = 100-500, and are positive integers.

2. A method for preparing an amino acid-functionalized MOF-based hybrid matrix membrane, characterized in that, Includes the following steps: (1) Synthesis of polyimide precursor; Under nitrogen protection and an ice-water bath, the diamine monomer was added to solvent D and stirred continuously until completely dissolved. Then, dianhydride monomer A was added to obtain a solution with a mass fraction of 10–25 wt.%. After reacting for 3 h, the ice-water bath was removed, and the reaction was continued at room temperature for 24 h. Catalyst E and dehydrating agent F were then added to the reaction system, and the reaction was continued at room temperature for 24 h. The product was poured into methanol to obtain a filamentous precipitate, which was washed several times with methanol and then dried under vacuum at 60–150 °C to finally obtain the polyimide precursor. The diamine monomer was diamine monomer B and / or diamine monomer C. Where m and n are the degrees of polymerization of polyimide, m and n = 100-500, and are positive integers; (2) Synthesizing amino acid-functionalized MOFs; Metal salt A was added to solvent B to obtain a metal salt A solution. The amino acid ligand, 2-methylimidazole, and basicity regulator C were added to solvents B and E and dissolved by stirring at room temperature to obtain an imidazole solution. The metal salt A solution was quickly poured into the imidazole solution to allow for complete ligand exchange. After the reaction was complete, the white suspension was centrifuged and washed repeatedly with methanol. The washed product was dried in a vacuum oven to obtain a white powder. (3) Preparation of amino acid-functionalized MOF-based hybrid matrix membranes: The amino acid-functionalized MOF synthesized in step (3) was activated in a vacuum drying oven and ultrasonically dispersed in solvent A to obtain a MOF dispersion. The polyimide precursor synthesized in step (1) was then dispersed in solvent A to obtain a polyimide precursor solution. The MOF dispersion was added to the polyimide precursor solution in multiple batches through a 0.45 μm microporous membrane filter and ultrasonically stirred to mix evenly. Then, air bubbles in the casting solution were removed by ultrasonication. After standing for a period of time, the mixture was poured into a culture dish and placed in a vacuum oven to dry and form a film, thus obtaining an amino acid-functionalized MOF-based mixed matrix membrane.

3. The method for preparing an amino acid-functionalized MOF-based hybrid matrix membrane according to claim 2, characterized in that, In step (1), the polyimide precursor is formed by the condensation polymerization of dianhydride monomers and diamine monomers; A can be any of the following dianhydride structures: ； B can be any of the following diamine structures: ； C can be any of the following diamine structures: ； Solvent D is one of anhydrous NMP, m-cresol, and DAMC; Catalyst E is triethylamine or pyridine; Dehydrating agent F is acetic anhydride; The molar ratio of diamine monomer to dianhydride monomer A is 1:1; The molar ratio of diamine monomer, catalyst E and dehydrating agent F is 1:1:

4.

4. The method for preparing an amino acid-functionalized MOF-based hybrid matrix membrane according to claim 2, characterized in that, In step (2), Metal salt A is one of zinc nitrate hexahydrate, zinc sulfate heptahydrate, and zinc acetate dihydrate; The amino acid ligands are L-proline, L-histidine, L-tyrosine, L-phenylalanine, or L-tryptophan; Alkalinity regulator C is one of sodium formate, 1-methylimidazole, or triethylamine; Solvent B is methanol or ethanol; Solvent E is deionized water; The volume ratio of solvent B to solvent E is 1-3:2; The molar ratio of metal salt A to 2-methylimidazole is 1:2-16; The molar ratio of alkaline regulator C to metal salt A is 1-8:1; The molar ratio of the amino acid ligand to 2-methylimidazole is 1:7-19; The exchange reaction takes 24-60 hours and is carried out at a temperature of 25°C. The centrifugation speed was 10,000 rpm, and the centrifugation time was 10 min; The drying temperature was 80℃, and the drying time was 24 hours.

5. The method for preparing an amino acid-functionalized MOF-based hybrid matrix membrane according to claim 2, characterized in that, In step (3), Solvent A is N,N-dimethylformamide or N,N-dimethylacetamide; The polymer mass fraction in the casting solution is 1-20 wt%; The ultrasonic stirring time is 12-24 h, and the ultrasonication time is 20 min. The settling time is 2 hours; The evaporation temperature of the casting solution is 50℃, and the time is 12-24 h.

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