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CN-121988170-A - Hollow fiber microfiltration membrane with high pollution resistance and preparation method and application thereof

CN121988170ACN 121988170 ACN121988170 ACN 121988170ACN-121988170-A

Abstract

The invention belongs to the field of preparation of special microfiltration membranes, and particularly relates to a hollow fiber microfiltration membrane with high pollution resistance, and a preparation method and application thereof. The preparation method comprises the steps of preparing spinning solution and core solution, spinning and forming, immobilizing a surface initiator, and in-situ polymerizing and grafting the amphoteric ion monomer under inert atmosphere and post-treating. The invention forms a stable hydration layer through covalent bond grafting, has lasting anti-pollution performance, basically does not lose membrane permeation flux, is suitable for separating and filtering complex solution rich in protein, polysaccharide, thalli and/or cell fragments, can be connected with the existing spinning technology, and is easy for scale.

Inventors

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Assignees

  • 成器智造(北京)科技有限公司

Dates

Publication Date
20260508
Application Date
20260318

Claims (10)

  1. 1. The preparation method of the hollow fiber microfiltration membrane with high pollution resistance is characterized by comprising the following steps of: (1) Adding a film-forming polymer into an organic solvent, preparing to obtain a film-forming solution, adding a pore-forming agent into the film-forming solution, and fully dissolving to obtain a spinning solution; (2) Preparing core liquid by mixing organic solvent with water to obtain core liquid, or independently using water as core liquid; (3) Extruding the spinning solution and the core solution through an outer side channel and an inner side channel of a spinneret respectively, and then entering a coagulating bath for phase separation, and solidifying and forming to obtain a nascent hollow fiber membrane; (4) Surface initiator immobilization, namely immersing the primary hollow fiber membrane into an initiator solution for reaction so as to enable the initiator to be immobilized on the surface of the primary hollow fiber membrane, and sequentially cleaning and drying after the reaction is completed to obtain an immobilized fiber membrane; (5) Surface in-situ polymerization grafting, namely placing the immobilized fiber membrane in an inert atmosphere reaction system, adding a polar solvent, a zwitterionic monomer, a catalyst and a ligand, and initiating atom transfer radical polymerization on the surface to obtain a grafted fiber membrane; (6) And (3) post-treatment, namely cleaning the grafted fiber membrane to remove unreacted substances, and then drying to obtain the hollow fiber microfiltration membrane with high pollution resistance.
  2. 2. The method for preparing a hollow fiber microfiltration membrane with high pollution resistance according to claim 1, wherein in step (1): the film-forming polymer is one or the combination of more than two of polysulfone, polyether sulfone, polyvinylidene fluoride and polyvinyl chloride; And/or the organic solvent is one or the combination of more than two of N-methyl pyrrolidone, N-dimethylformamide, N-dimethylacetamide and dimethyl sulfoxide; and/or, the mass fraction of the film-forming polymer in the film-forming solution is 17-25%.
  3. 3. The method for preparing a hollow fiber microfiltration membrane with high pollution resistance according to claim 1, wherein in step (1): The pore-forming agent is polyvinylpyrrolidone and/or polyethylene glycol; And/or, the addition amount of the pore-forming agent is 6-14% based on 100% of the total mass of the spinning solution.
  4. 4. The method for preparing a hollow fiber microfiltration membrane with high pollution resistance according to claim 1, wherein in the step (2): the organic solvent is one or the combination of more than two of N-methyl pyrrolidone, N-dimethylformamide, N-dimethylacetamide and dimethyl sulfoxide; And/or when the core liquid is a mixed liquid of the organic solvent and water, the proportion of the organic solvent is 1-85%.
  5. 5. The method for preparing the high-pollution-resistance hollow fiber microfiltration membrane according to claim 1, wherein in the step (3), the coagulating bath is water or a mixed solution of an organic solvent and water, and when the coagulating bath is a mixed solution of the organic solvent and water, the proportion of the organic solvent is 1-70%, and the organic solvent is one or a combination of more than two of N-methylpyrrolidone, N-dimethylformamide, N-dimethylacetamide and dimethyl sulfoxide.
  6. 6. The method for preparing a hollow fiber microfiltration membrane with high pollution resistance according to claim 1, wherein in the step (4): The initiator solution is toluene or normal hexane solution of an ATRP initiator, and the ATRP initiator is 2-bromoisobutyryl bromide or 2-bromoisobutyric acid-hydroxyethyl ester; and/or the temperature of the reaction is 20-40 ℃ and the reaction time is 2-12h; and/or the cleaning mode is to use water, ethanol, methanol or N, N-dimethylformamide for cleaning.
  7. 7. The method for preparing a hollow fiber microfiltration membrane with high pollution resistance according to claim 1, wherein in step (5): the inert atmosphere is nitrogen atmosphere or argon atmosphere; And/or the polar solvent is one or more than two of water, ethanol, methanol and N, N-dimethylformamide; And/or the zwitterionic monomer is one or the combination of more than two of sulfobetaine, carboxyl betaine and phosphorylcholine methacrylate; and/or the catalyst is cuprous bromide; and/or the ligand is pentamethyldiethylenetriamine or tris (2-bipyridylmethyl) amine; and/or the mol ratio of the zwitterionic monomer to the catalyst to the ligand is 100:1:1-3; and/or the temperature of the atom transfer radical polymerization is 20-80 ℃ and the time is 0.5-12h.
  8. 8. The method for preparing a hollow fiber microfiltration membrane with high pollution resistance according to claim 1, wherein in step (6): the cleaning mode is that water, ethanol, methanol or N, N-dimethylformamide is adopted for cleaning; and/or drying the mixture for 12-24 hours at 40-60 ℃ under vacuum.
  9. 9. A highly anti-fouling hollow fiber microfiltration membrane obtained by the production process of any one of claims 1 to 8.
  10. 10. Use of a highly anti-fouling hollow fiber microfiltration membrane according to claim 9 for separating and/or filtering a solution containing proteins, polysaccharides, thalli and/or cell debris.

Description

Hollow fiber microfiltration membrane with high pollution resistance and preparation method and application thereof Technical Field The invention belongs to the field of preparation of special microfiltration membranes, and particularly relates to a hollow fiber microfiltration membrane with high pollution resistance, and a preparation method and application thereof. Background In the fields of biological manufacturing and research and development, ensuring the sterile state of solutions is a basic stone for ensuring the safety and effectiveness of products. Wherein, the hollow fiber micro-filtration membrane with the aperture of 0.2 μm has been widely used in the sterilization process of biological medicine because of the advantages of high filling density, large specific surface area and the like. The membrane separation technology can effectively remove microorganisms such as bacteria and the like through a physical screening mechanism, thereby achieving strict pharmacopoeia sterile requirements. However, when dealing with complex solutions rich in proteins, polysaccharides, thalli or cell debris, the membrane fouling problem is extremely severe, leading to rapid decay of filtration flux, increased operating pressure, shortened membrane lifetime, greatly increasing operating costs and process instability. At present, methods for improving the pollution resistance of the microfiltration membrane mainly comprise physical blending modification, surface coating modification and the like. Wherein the physical blending modification is to blend inorganic nano particles (such as TiO 2、SiO2) into the feed liquid. CN118341271a discloses a high anti-pollution microfiltration membrane wire and a preparation method thereof, which successfully prepares the anti-pollution microfiltration membrane wire by adding nano-particles such as nano-zirconium dioxide or nano-cerium dioxide in feed liquid, however, the nano-particles added by the method are easy to agglomerate in the membrane, cause defect points, and accelerate pollution instead. In addition, small molecules or nanoparticles leach out of the membrane matrix during long-term operation or chemical cleaning, resulting in rapid decay of anti-fouling properties and possible contamination of the product. Surface coating modification means coating a hydrophilic or zwitterionic polymer coating on the surface of the formed film. CN110813103a discloses a preparation method of various antibacterial and anti-pollution hollow fiber membranes, which greatly improves the hydrophilicity of hollow fiber membrane filaments by preparing nano silver particles/graphene composite materials and then adding the nano silver particles/graphene composite materials into spinning solution, thereby improving the anti-pollution performance of the membrane filaments. However, the nano silver particles and graphene used in the method have a tendency to aggregate easily, and once the nano silver particles and graphene are unevenly dispersed, the nano silver particles and the graphene can cause defects of a film structure to influence the performance. In addition, nano silver particles may have a problem of easy oxidative discoloration. During long-term operation, particularly during frequent chemical cleaning, the nano silver particles risk falling off, leaching, which may lead to a decrease in antibacterial properties, and leached silver may have a potential impact on the environment. Therefore, aiming at the technical problems, the invention develops a novel 0.2 mu m microfiltration membrane. The microfiltration membrane not only has the traditional sterilization capability, but also breaks through in the aspects of pollution resistance, chemical stability, low protein adsorptivity, high flux maintenance and the like, thereby comprehensively improving the filtration efficiency, economy and reliability so as to meet the higher pursuit of the modern biomedical industry on production and quality. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a preparation method of a hollow fiber microfiltration membrane with high pollution resistance, which comprises the following steps: (1) Adding a film-forming polymer into an organic solvent, preparing to obtain a film-forming solution, adding a pore-forming agent into the film-forming solution, and fully dissolving to obtain a spinning solution; (2) Preparing core liquid by mixing organic solvent with water to obtain core liquid, or independently using water as core liquid; (3) Extruding the spinning solution and the core solution through an outer side channel and an inner side channel of a spinneret respectively, and then entering a coagulating bath for phase separation, and solidifying and forming to obtain a nascent hollow fiber membrane; (4) Surface initiator immobilization, namely immersing the primary hollow fiber membrane into an initiator solution for reaction so as to enable the initiator to be immobi