A perfluorinated separation membrane resistant to organic solvents

Abstract

The purpose of the present invention is to provide a perfluorinated separation membrane resistant to organic solvents, which is applied to industrial separation in the petrochemical, fine chemical, biopharmaceutical and other industries. The perfluorinated separation membrane has a high content of fluorine, which can improve the swelling resistance and separation performance of the polymer membrane to organic solvents in the separation of organic-organic azeotropic systems.

Description

Technical Field

[0001] The invention relates to a separation membrane material, in particular to an organic solvent-resistant perfluorinated separation membrane. The prepared organic solvent-resistant perfluorinated separation membrane can be used in the field of organic-organic system separation in industries such as petrochemicals, fine chemicals, and biopharmaceuticals. Background Art

[0002] The separation and purification of organic-organic mixtures is still a major challenge in the current petrochemical, fine chemical, biopharmaceutical and other industries. Common organic-organic azeotropic systems include DMC-methanol, MTBE-methanol, toluene-formic acid, etc. Compared with the gas-liquid equilibrium line of processes such as atmospheric distillation, membrane technology has significant energy consumption advantages. It does not require the addition of a third component and can directly break the organic-organic azeotropic equilibrium. Compared with traditional polydimethylsiloxane membranes (PDMS), fluorinated polydimethylsiloxane membranes obtained by introducing fluorinated silanes have significant resistance to organic solvent swelling and exhibit excellent alcohol-water separation performance [1-2]. Kujawski et al. in Poland introduced fluorinated MOF-808 into polydimethylsiloxane to obtain a self-supporting mixed matrix homogeneous membrane, which was used to separate a variety of ether-alcohol and ester-alcohol binary systems. It was found that due to the hydrophobic properties of fluorinated MOF-808 itself, the affinity between ether molecules and ester molecules in the separation system and fluorinated MOF-808 was greater than the affinity between alcohol molecules and fluorinated MOF-808, which was more conducive to the improvement of membrane separation performance [3]. Professor Qin Peiyong's research group at Beijing University of Chemical Technology polymerized methacrylate-based PDMS and dodecafluoroheptyl methacrylate to obtain a fluorinated PDMS coating liquid, and prepared a composite membrane on a PVDF-based membrane by spin coating [4]. Patent CN 114432893 A discloses a fluorinated pervaporation membrane and its preparation method, which is aimed at the separation of ethanol-water solution systems. The main polysiloxane chain described is still the common hydroxyl PDMS, and the fluorine element in the cross-linked PDMS network is obtained by introducing a cross-linking agent containing fluorinated silane. The fluorinated PDMS membranes reported in the above studies are all prepared by introducing fluorinated silane or adding fluorine-modified nanoparticles, so the fluorine content in the separation membrane layer is limited. By searching the literature and patents, there has been no related research on the use of perfluorinated separation membranes in organic-organic azeotropic systems. Therefore, the present invention is the first to start from the membrane structure design, screen membrane materials with high fluorine content, and construct a new type of perfluorinated separation membrane.

[0003] References:

[0004] [1] P.-Y. Zheng, X.-Q. Li, J.-K. Wu, N.-X. Wang, J. Li, Q.-F. An, Enhanced butanol selectivity of pervaporation membrane with fluorinated monolayer on polydimethylsiloxane surface, J. Membr. Sci., 548 (2018) 215-222.

[0005] [2] H.P. Zhu, X.R. Li, Y. Pan, G.P. Liu, H. Wu, M. Jiang, W.Q. Jin, Fluorinated PDMS membrane with anti-biofouling property for in-situ biobutanol recovery from fermentation-pervaporation coupled process, J. Membr. Sci., 609 (2020) 118225.

[0006] [3] K. Knozowska, R. Thür, J. Kujawa, I. Kolesnyk, I.F.J. Vankelecom, W. Kujawski, Fluorinated MOF-808 with various modulators to fabricate high-performance hybrid membranes with enhanced hydrophobicity for organic-organic pervaporation, Sep. Purif. Technol., 264 (2021) 118315.

[0007] [4] Z.H. Si, Y.Q. Wang, C. Liu, T.L. Xue, S. Yang, G.Z. Li, C.W. Zhang, B. Chen, D. Cai, P.Y. Qin, Fluoroalkyl-grafted methacrylate-PDMS membrane using fluoromonomer as diluent for enhancing biobutanol pervaporation, Green Chem., 23 (2021) 7053-7064. Summary of the Invention

[0008] The purpose of the present invention is to provide a new type of perfluorinated separation membrane resistant to organic solvents. This membrane material helps the membrane method to obtain practical industrial separation applications in the petrochemical, fine chemical, biopharmaceutical and other industries. In addition, the perfluorinated separation membrane has a high content of fluorine element. In the separation of organic-organic azeotropic systems, it can improve the swelling resistance and separation performance of the polymer membrane to organic solvents.

[0009] The invention provides a perfluorinated separation membrane resistant to organic solvents, the perfluorinated separation membrane comprising a fluorinated base membrane and a fluorinated separation layer supported on the fluorinated base membrane, the fluorinated separation layer being formed by blending fluorinated silicone oil and fluorinated additives.

[0010] Preferably, the fluorine-containing silicone oil is selected from hydroxyl fluorine-containing silicone oil, vinyl fluorine-containing silicone oil, and terminal hydrogen fluorine-containing silicone oil, and the viscosity of the fluorine-containing silicone oil is 1000-10000 cP; the fluorine-containing additive is one or more of fluorine-containing silane, fluorine-containing thiol, and fluorine-containing organic acid; the fluorine-containing base film is one of fluorine-containing polyimide, fluorine-containing polyamide, polyvinylidene fluoride, and polytetrafluoroethylene.

[0011] Preferably, the fluorine-containing separation layer is formed by blending fluorine-containing silicone oil, fluorine-containing additives and fluorine-containing MOF nanoparticles.

[0012] The present invention also provides a method for preparing a perfluorinated separation membrane resistant to organic solvents, the method comprising the following steps:

[0013] S1: Preparation of coating liquid: fluorine-containing silicone oil and fluorine-containing reagent or fluorine-containing silicone oil, fluorine-containing reagent and fluorine-containing MOF nanoparticles are mixed in a certain proportion, and a blend having a certain viscosity is formed after stirring, standing and degassing;

[0014] S2: Preparation of fluorine-containing base film: dissolving the fluorine-containing polymer in an organic solvent to form a uniform solution, and uniformly coating the solution on a non-woven fabric to form a fluorine-containing base film;

[0015] S3: Preparation of perfluorinated separation membrane: the blend is spread on a fluorinated base membrane, a scraper of a certain thickness is used to scrape the surface of the fluorinated base membrane, and the mixture is dried at a certain temperature to obtain a perfluorinated separation membrane.

[0016] Preferably, the fluorine-containing MOF nanoparticles in step S1 are fluorine-functionalized metal organic framework MOF, preferably one of UiO-66-F4, NbOFFIVE-1-Ni, UiO-66-(CF3)2, 2QMOF-2F, and MAF-2F.

[0017] Preferably, the mass ratio of the fluorine-containing silicone oil and the fluorine-containing reagent or the fluorine-containing silicone oil, the fluorine-containing reagent and the fluorine-containing MOF nanoparticles in step S1 is 2-10:1-4; 2-10:1-4:0.2-2 respectively.

[0018] Preferably, in step S1, the stirring speed is 500-1500 rpm, the stirring time is 10-60 minutes, and the certain viscosity is 2000-5000 centipoise.

[0019] Preferably, the organic solvent in step S2 is one of N,N-dimethylacetamide, dimethyl sulfoxide, and tetrahydrofuran, and the film-forming method is a dry-wet phase conversion method or a hot melt method.

[0020] Preferably, the scraper used for scraping in step S3 is 30-500 microns, the drying temperature is 50-150° C., and the drying time is 2-12 hours.

[0021] Preferably, step S2 and step S3 are completed sequentially on the same production line.

[0022] The organic solvent-resistant perfluorinated separation membrane prepared by the present invention is used in the separation of organic-organic azeotropic systems, wherein one organic substance is alcohol, and is preferably suitable for organic-organic azeotropic systems such as ester / alcohol and ether / alcohol.

[0023] Preferably, the other organic substance is dimethyl carbonate.

[0024] Beneficial effects:

[0025] The perfluorinated separation membrane prepared by the present invention utilizes the double-repellent (hydrophobic and oleophobic) properties of the fluorine elements of trifluoropropyl and fluoroalkane chains in the polymer network structure formed by curing the fluorinated polymer and the fluorinated additive to reduce the solubility coefficient and diffusion coefficient of methanol molecules in the perfluorinated polymer cortex. At the same time, the fluorine-containing element in the base film material plays a key role in the separation of the DMC / methanol azeotropic system. Therefore, in the membrane separation process of the DMC / methanol azeotropic system, the fluorinated interface has the characteristics of low surface energy, which improves its affinity for DMC, but reduces its affinity for methanol. The perfluorinated separation membrane prepared by the present invention is all prepared from fluorinated raw materials, because of its high fluorine content, it shows high separation performance, and has excellent resistance to organic solvents, and has commercial and industrial application value in the organic-organic azeotropic system. In addition, the film-making process provided by the present invention can realize the coordinated completion of base film preparation and separation layer coating, which is conducive to simplifying the film-making process. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Process flow chart for large-scale production of perfluorinated separation membranes

[0027] 1- non-woven fabric; 2- scraper head; 3- stainless steel 316 drum; 4- linkage shaft; 5- coagulation bath; 6- oven.

[0028] Figure 2These are cross-sectional and surface SEM images of the (ab) hydroxyl fluorinated silicone oil / PTFE composite membrane cross-linked with perfluorooctyltrimethoxysilane in Example 5 and the (cd) hydroxyl fluorinated silicone oil / PTFE composite membrane cross-linked with UiO-66-F4 / perfluorooctyltrimethoxysilane in Example 6.

[0029] Figure 3 The 5-month long-term stability of the hydroxyl fluorinated silicone oil / PTFE composite membrane cross-linked with perfluorooctyltrimethoxysilane (Example 5) for separating the DMC / methanol azeotropic system. DETAILED DESCRIPTION

[0030] Figure 1 For the present invention Figure 1 The process flow chart for large-scale production of perfluorinated separation membranes is shown in the figure. The fluorinated base membrane material is dissolved in an organic solvent, stirred evenly, and then directly coated on a non-woven fabric 1. The preparation of the fluorinated base membrane is completed with the cooperation of a stainless steel drum 3 and a scraper 1. The base membrane is driven by multiple linkage shafts 4, and the phase transformation of the fluorinated polymer is completed in a coagulation bath 5. Then, the mixed blend is continuously coated on the fluorinated base membrane, and a wet perfluorinated separation membrane of a certain thickness is obtained with the cooperation of a stainless steel drum 3 and a scraper 1. The solvent is removed and rolled up by rapid drying in an oven 6.

[0031] Example 1

[0032] Hydroxy silicone oil and tetraethyl orthosilicate were blended at a mass ratio of 5:1, stirred at a speed of 100 rpm for 1 hour, allowed to stand for 4 hours, and degassed to obtain a coating liquid with a viscosity of 30 ripoles.

[0033] A commercial alumina ceramic tube with a pore size of 200 nm was selected as the support.

[0034] The alumina ceramic tube was moved up and down at a speed of 0.2 m / min, immersed in a coating liquid with a viscosity of 30 ripoles for 1 minute, and dried at 100°C for 1 hour to obtain a tetraethyl orthosilicate cross-linked hydroxy silicone oil / alumina ceramic composite film.

[0035] The tetraethyl orthosilicate cross-linked hydroxy silicone oil / alumina ceramic composite membrane prepared in this example was measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average DMC concentration on the permeate side were 5.2g / m2h and 40.9wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average toluene concentration on the permeate side were 7.8g / m2h and 39.5wt%, respectively.

[0036] Example 2

[0037] Hydroxy silicone oil and tetraethyl orthosilicate were blended at a mass ratio of 5:1, stirred at a speed of 100 rpm for 1 hour, allowed to stand for 4 hours, and degassed to obtain a coating liquid with a viscosity of 30 ripoles.

[0038] 30 wt% polyacrylonitrile PAN powder was dissolved in DMF, stirred for 5 h and degassed. The nonwoven fabric was moved at a speed of 1.5 m / min, the PAN base film was coated on its surface, and the phase inversion was completed in a water bath.

[0039] A coating liquid with a viscosity of 30 ripoles was coated on the surface of the PAN base film at a moving speed of 0.5 m / min by a 60-μm wire rod and dried at 130° C. for 1 hour to obtain a tetraethyl orthosilicate cross-linked hydroxy silicone oil / PAN composite film.

[0040] The tetraethyl orthosilicate cross-linked hydroxy silicone oil / PAN composite membrane prepared in this example was measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average DMC concentration on the permeate side were 29.3g / m2h and 33.5wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average toluene concentration on the permeate side were 15.2g / m2h and 36.3wt%, respectively.

[0041] Example 3

[0042] Hydroxy silicone oil and perfluorooctyltrimethoxysilane were blended at a mass ratio of 5:1, stirred at a speed of 100 rpm for 1 hour, allowed to stand for 4 hours, and degassed to obtain a coating solution with a viscosity of 30 ripoles.

[0043] 30 wt% polyvinylidene fluoride PVDF powder was dissolved in DMF, stirred for 5 hours and degassed. The non-woven fabric was moved at a speed of 1.5 m / min, the PVDF base film was coated on its surface, and the phase inversion was completed in a water bath.

[0044] A coating liquid with a viscosity of 30 ripoles was coated on the surface of the PVDF base film at a moving speed of 0.5 m / min using a 60-μm wire rod and dried at 130° C. for 1 hour to obtain a hydroxy silicone oil / PVDF composite film cross-linked with perfluorooctyltrimethoxysilane.

[0045] The perfluorooctyltrimethoxysilane cross-linked hydroxy silicone oil / PVDF composite membrane prepared in this example was measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average DMC concentration on the permeate side were 9.2g / m2h and 50.7wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average toluene concentration on the permeate side were 4.9g / m2h and 58.8wt%, respectively.

[0046] Example 4

[0047] Hydroxy fluorinated silicone oil and perfluorooctyltrimethoxysilane were blended at a mass ratio of 5:1, stirred at a speed of 100 rpm for 1 hour, allowed to stand for 4 hours, and degassed to obtain a coating solution with a viscosity of 30 ripoles.

[0048] 30 wt% polyvinylidene fluoride PVDF powder was dissolved in DMF, stirred for 5 hours and degassed. The non-woven fabric was moved at a speed of 1.5 m / min, the PVDF base film was coated on its surface, and the phase inversion was completed in a water bath.

[0049] A coating liquid with a viscosity of 30 ripoles was coated on the surface of the PVDF base film at a moving speed of 0.5 m / min using a 60 μm wire rod and dried at 130° C. for 1 hour to obtain a perfluorooctyltrimethoxysilane cross-linked hydroxyl fluorinated silicone oil / PVDF composite membrane.

[0050] The perfluorooctyltrimethoxysilane cross-linked hydroxyl fluorinated silicone oil / PVDF composite membrane prepared in this example was measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average DMC concentration on the permeate side were 10.6g / m2h and 54.1wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average toluene concentration on the permeate side were 4.7g / m2h and 60.9wt%, respectively.

[0051] Example 5

[0052] Hydroxy fluorinated silicone oil and perfluorooctyltrimethoxysilane were blended at a mass ratio of 5:1, stirred at a speed of 100 rpm for 1 hour, allowed to stand for 4 hours, and degassed to obtain a coating solution with a viscosity of 30 ripoles.

[0053] The nonwoven fabric moves at a speed of 1.5 m / min, and a PTFE resin film is formed on its surface by a hot melt method.

[0054] A coating liquid with a viscosity of 30 ripoles was coated on the surface of the PTFE base membrane at a moving speed of 0.5 m / min through a 60-μm wire rod and dried at 130° C. for 1 hour to obtain a perfluorooctyltrimethoxysilane cross-linked hydroxyl fluorinated silicone oil / PTFE composite membrane.

[0055] The perfluorooctyltrimethoxysilane cross-linked hydroxyl fluorinated silicone oil / PTFE composite membrane prepared in this example was measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average permeate side DMC concentration were 13.9g / m2h and 60.5wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average permeate side toluene concentration were 6.7g / m2h and 69.9wt%, respectively. The cross-sectional and surface SEM images of the membrane are shown in FIG. Figure 2 The 5-month long-term stability of the DMC / methanol azeotropic system is shown in ab. Figure 3 shown.

[0056] Example 6

[0057] Hydroxy fluorinated silicone oil, perfluorooctyltrimethoxysilane and UiO-66-F4 were mixed in a mass ratio of 5:1:0.5, stirred at a speed of 100 rpm for 1 hour, allowed to stand for 4 hours, and a coating liquid with a viscosity of 30 ripoles was obtained after degassing.

[0058] The nonwoven fabric moves at a speed of 1.5 m / min, and a PTFE resin film is formed on its surface by a hot melt method.

[0059] A coating liquid with a viscosity of 30 ripoles was coated on the surface of the PTFE base membrane at a moving speed of 0.5 m / min using a 60-μm wire rod and dried at 130° C. for 1 hour to obtain a UiO-66-F4 / perfluorooctyltrimethoxysilane cross-linked hydroxyl fluorinated silicone oil / PTFE composite membrane.

[0060] The UiO-66-F4 / perfluorooctyltrimethoxysilane cross-linked hydroxyl fluorinated silicone oil / PTFE composite membrane prepared in this example was measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average permeate side DMC concentration were 12.7g / m2h and 65.9wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average permeate side toluene concentration were 5.8g / m2h and 70.7wt%, respectively. The cross-sectional and surface SEM images of the membrane are shown in FIG. Figure 2 cd shown

[0061] Example 7

[0062] Vinyl fluorosilicone oil and perfluorodecyltriethoxysilane were blended in a mass ratio of 3:1, stirred at a speed of 80 rpm for 2 hours, allowed to stand for 6 hours, and degassed to obtain a coating solution with a viscosity of 25 ripoles.

[0063] 50 wt% of fluorinated polyimide powder was dissolved in THF, stirred for 12 h and degassed. The nonwoven fabric was moved at a speed of 1.2 m / min, the fluorinated polyimide base film was coated on its surface, and phase inversion was completed in a water bath.

[0064] A coating liquid with a viscosity of 25 ripoles was coated on the surface of the fluorinated polyimide base film at a moving speed of 0.3 m / min using a 100 μm wire rod and dried at 100° C. for 2.5 hours to obtain a vinyl fluorosilicone oil / fluorinated polyimide composite film cross-linked with perfluorodecyltriethoxysilane.

[0065] The perfluorodecyltriethoxysilane cross-linked vinyl fluorosilicone oil / fluorinated polyimide composite membrane prepared in this example was measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average DMC concentration on the permeate side were 16.0g / m2h and 52.5wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average toluene concentration on the permeate side were 4.7g / m2h and 60.4wt%, respectively.

[0066] Example 8

[0067] Vinyl fluorosilicone oil, perfluorodecyl triethoxysilane and MAF-2F were blended in a mass ratio of 3:1:0.3, stirred at a speed of 80 rpm for 2 hours, allowed to stand for 6 hours, and degassed to obtain a coating solution with a viscosity of 25 ripoles.

[0068] 50 wt% of fluorinated polyimide powder was dissolved in THF, stirred for 12 h and degassed. The nonwoven fabric was moved at a speed of 1.2 m / min, the fluorinated polyimide base film was coated on its surface, and phase inversion was completed in a water bath.

[0069] A coating liquid with a viscosity of 25 ripoles was coated on the surface of the fluorinated polyimide base film at a moving speed of 0.3 m / min using a 100 μm wire rod and dried at 100° C. for 2.5 hours to obtain a MAF-2F / perfluorodecyltriethoxysilane cross-linked vinyl fluorosilicone oil / fluorinated polyimide composite film.

[0070] The MAF-2F / perfluorodecyltriethoxysilane cross-linked vinyl fluorosilicone oil / fluorinated polyimide composite membrane prepared in this example was measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average DMC concentration on the permeate side were 15.8g / m2h and 54.5wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average toluene concentration on the permeate side were 4.4g / m2h and 62.3wt%, respectively.

[0071] Example 9

[0072] Vinyl fluorosilicone oil, terminal hydrogen fluorosilicone oil and perfluorodecyltrimethoxysilane were blended in a mass ratio of 4:1:2.5, stirred at a speed of 150 rpm for 3 hours, allowed to stand for 3 hours, and degassed to obtain a coating liquid with a viscosity of 40 ripoles.

[0073] 40 wt% fluorinated polyamide powder was dissolved in DMSO, stirred for 8 h and degassed. The nonwoven fabric was moved at a speed of 1.8 m / min, the fluorinated polyamide base film was coated on its surface, and the phase inversion was completed in a water bath.

[0074] A coating liquid with a viscosity of 40 ripoles was coated on the surface of the fluorinated polyamide base film at a moving speed of 0.7 m / min using a 30 μm wire rod and dried at 80°C for 3 hours to obtain perfluorodecyltrimethoxysilane cross-linked vinyl fluorosilicone oil and terminal hydrogen fluorosilicone oil / fluorinated polyimide composite films.

[0075] The perfluorodecyltrimethoxysilane cross-linked vinyl fluorosilicone oil and terminal hydrogen fluorosilicone oil / fluorinated polyamide composite membranes prepared in this example were measured. When separating 30wt% DMC-methanol at 40°C, the average membrane flux and the average DMC concentration on the permeate side were 14.7g / m2h and 53.6wt%, respectively; when separating 31wt% toluene-methanol, the average membrane flux and the average toluene concentration on the permeate side were 4.3g / m2h and 61.9wt%, respectively.

Claims

1. A perfluorinated separation membrane resistant to organic solvents, It is characterized in that The perfluorinated separation membrane comprises a fluorine-containing base membrane and a fluorine-containing separation layer supported on the fluorine-containing base membrane, wherein the fluorine-containing separation layer is a mixture of fluorine-containing silicone oil and a fluorine-containing additive; The fluorinated silicone oil is selected from hydroxy fluorinated silicone oil, vinyl fluorinated silicone oil, hydrogen-terminated fluorinated silicone oil, and the viscosity of the fluorinated silicone oil is 1000-10000 cP; the fluorinated additive is one or more of fluorinated silane, fluorinated thiol, and fluorinated organic acid; the fluorinated base film is one of fluorinated polyimide, fluorinated polyamide, polyvinylidene fluoride, and polytetrafluoroethylene; The method for preparing the perfluorinated separation membrane comprises the following steps: S1: Preparation of coating liquid: fluorine-containing silicone oil and fluorine-containing additive are mixed in a certain proportion, and a blend having a certain viscosity is formed after stirring, standing and degassing; S2: Preparation of fluorine-containing base film: dissolving a fluorine-containing polymer in an organic solvent to form a uniform solution, and uniformly coating the solution on a non-woven fabric to form a fluorine-containing base film; S3: Preparation of perfluorinated separation membrane: the blend is spread on a fluorinated base membrane, a scraper with a certain thickness is used to scrape the surface of the fluorinated base membrane, and the mixture is dried at a certain temperature to obtain a perfluorinated separation membrane.

2. The perfluorinated separation membrane according to claim 1, It is characterized in that The fluorine-containing separation layer is formed by mixing fluorine-containing silicone oil, fluorine-containing additives and fluorine-containing MOF nanoparticles.

3. The perfluorinated separation membrane according to claim 2, It is characterized in that The fluorine-containing MOF nanoparticles described in step S1 are fluorine-functionalized metal organic framework MOF, and the fluorine-functionalized metal organic framework MOF is UiO-66-F4, NbOFFIVE-1-Ni, UiO-66-(CF 3 ) 2 , 2QMOF-2F, or one of MAF-2F.

4. The perfluorinated separation membrane according to claim 1, It is characterized in that The mass ratio of the fluorine-containing silicone oil to the fluorine-containing reagent in step S1 is 2-10:1-4 respectively; the stirring speed in step S1 is 500-1500 rpm, the stirring time is 10-60 minutes, and the certain viscosity is 2000-5000 centipoise.

5. The perfluorinated separation membrane according to claim 2, It is characterized in that The mass ratio of the fluorinated silicone oil, the fluorinated reagent and the fluorinated MOF nanoparticles in step S1 is 2-10:1-4:0.2-2; the stirring speed in step S1 is 500-1500 rpm, the stirring time is 10-60 minutes, and the certain viscosity is 2000-5000 centipoise.

6. The perfluorinated separation membrane according to claim 1, It is characterized in that The organic solvent described in step S2 is one of N,N-dimethylacetamide, dimethyl sulfoxide, and tetrahydrofuran, and the film forming method is a dry-wet phase conversion method or a hot melt method.

7. Use of the organic solvent-resistant perfluorinated separation membrane according to claim 1 or 2 in the separation of an organic-organic azeotropic system, wherein one organic substance is alcohol and the other organic substance is specifically dimethyl carbonate.

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