CN113457465A - Polyvinylidene fluoride hollow fiber ultrafiltration membrane and preparation method thereof - Google Patents
Polyvinylidene fluoride hollow fiber ultrafiltration membrane and preparation method thereof Download PDFInfo
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- CN113457465A CN113457465A CN202110805244.7A CN202110805244A CN113457465A CN 113457465 A CN113457465 A CN 113457465A CN 202110805244 A CN202110805244 A CN 202110805244A CN 113457465 A CN113457465 A CN 113457465A
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- 239000012528 membrane Substances 0.000 title claims abstract description 125
- 239000002033 PVDF binder Substances 0.000 title claims abstract description 43
- 229920002981 polyvinylidene fluoride Polymers 0.000 title claims abstract description 43
- 238000000108 ultra-filtration Methods 0.000 title claims abstract description 43
- 239000012510 hollow fiber Substances 0.000 title claims abstract description 38
- 238000002360 preparation method Methods 0.000 title claims abstract description 17
- 239000010410 layer Substances 0.000 claims abstract description 26
- 238000000926 separation method Methods 0.000 claims abstract description 26
- 239000002344 surface layer Substances 0.000 claims abstract description 22
- 239000011148 porous material Substances 0.000 claims abstract description 19
- 238000009987 spinning Methods 0.000 claims abstract description 13
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 30
- 238000003756 stirring Methods 0.000 claims description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 16
- 238000005266 casting Methods 0.000 claims description 14
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 claims description 9
- 239000003960 organic solvent Substances 0.000 claims description 9
- 239000002202 Polyethylene glycol Substances 0.000 claims description 8
- 238000001914 filtration Methods 0.000 claims description 8
- 229920001223 polyethylene glycol Polymers 0.000 claims description 8
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 claims description 6
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 6
- 238000007654 immersion Methods 0.000 claims description 6
- 239000003607 modifier Substances 0.000 claims description 6
- 238000001556 precipitation Methods 0.000 claims description 6
- 239000008237 rinsing water Substances 0.000 claims description 6
- 239000002562 thickening agent Substances 0.000 claims description 6
- 238000007605 air drying Methods 0.000 claims description 5
- 230000014759 maintenance of location Effects 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- 229920002503 polyoxyethylene-polyoxypropylene Polymers 0.000 claims description 5
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 4
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 claims description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 4
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 4
- 229920001400 block copolymer Polymers 0.000 claims description 4
- 239000012467 final product Substances 0.000 claims description 4
- -1 polyoxyethylene Polymers 0.000 claims description 4
- 229920000036 polyvinylpyrrolidone Polymers 0.000 claims description 3
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 3
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims description 3
- 238000002791 soaking Methods 0.000 claims description 3
- 229920001747 Cellulose diacetate Polymers 0.000 claims description 2
- 229920001661 Chitosan Polymers 0.000 claims description 2
- 239000004354 Hydroxyethyl cellulose Substances 0.000 claims description 2
- 229920000663 Hydroxyethyl cellulose Polymers 0.000 claims description 2
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 claims description 2
- 229920003171 Poly (ethylene oxide) Polymers 0.000 claims description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 2
- 239000004088 foaming agent Substances 0.000 claims description 2
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 2
- 235000019447 hydroxyethyl cellulose Nutrition 0.000 claims description 2
- 239000007788 liquid Substances 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
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- 239000004814 polyurethane Substances 0.000 claims description 2
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 2
- 239000002994 raw material Substances 0.000 claims description 2
- DQWPFSLDHJDLRL-UHFFFAOYSA-N triethyl phosphate Chemical compound CCOP(=O)(OCC)OCC DQWPFSLDHJDLRL-UHFFFAOYSA-N 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 4
- 239000000463 material Substances 0.000 abstract description 3
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- 238000011056 performance test Methods 0.000 description 4
- 229920001155 polypropylene Polymers 0.000 description 4
- 239000012298 atmosphere Substances 0.000 description 3
- 239000003651 drinking water Substances 0.000 description 3
- 235000020188 drinking water Nutrition 0.000 description 3
- 229920006316 polyvinylpyrrolidine Polymers 0.000 description 3
- 238000000746 purification Methods 0.000 description 3
- 239000010865 sewage Substances 0.000 description 3
- 239000008235 industrial water Substances 0.000 description 2
- 238000005191 phase separation Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
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- BQCIDUSAKPWEOX-UHFFFAOYSA-N 1,1-Difluoroethene Chemical compound FC(F)=C BQCIDUSAKPWEOX-UHFFFAOYSA-N 0.000 description 1
- 229920012266 Poly(ether sulfone) PES Polymers 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
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- 238000011118 depth filtration Methods 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/08—Hollow fibre membranes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/14—Ultrafiltration; Microfiltration
- B01D61/145—Ultrafiltration
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/08—Hollow fibre membranes
- B01D69/087—Details relating to the spinning process
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/30—Polyalkenyl halides
- B01D71/32—Polyalkenyl halides containing fluorine atoms
- B01D71/34—Polyvinylidene fluoride
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/12—Specific ratios of components used
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/02—Details relating to pores or porosity of the membranes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/02—Details relating to pores or porosity of the membranes
- B01D2325/022—Asymmetric membranes
- B01D2325/023—Dense layer within the membrane
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/36—Hydrophilic membranes
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Water Supply & Treatment (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
A polyvinylidene fluoride hollow fiber ultrafiltration membrane and a preparation method thereof belong to the technical field of ultrafiltration separation membrane materials. Micropores are distributed on the inner surface layer and the outer surface layer of the membrane; the middle part of the membrane is a compact separation layer, and the average pore diameter is 0.01-0.03 mu m; the pore diameter of the micropores gradually increases from the middle part to the two ends of the membrane layer, and the average pore diameter of the micropores on the two sides of the compact separation layer is 0.03-0.2 μm. The polyvinylidene fluoride hollow fiber ultrafiltration membrane and the preparation method thereof have the advantages that micropores on the section of the membrane are completely asymmetric sponge-shaped without large cavities, the micropores are uniformly distributed on the inner surface and the outer surface, the middle part of the membrane is a separation layer, the pore diameters of the micropores from the middle part to the two ends of the membrane layer are gradually increased, the separation effect is not easily influenced by scratching or scraping in use, and the strength of the membrane is effectively improved by the sponge pore structure of the section; the spinning process is easy to control, good in film performance repeatability and convenient for large-scale production.
Description
Technical Field
The invention belongs to the technical field of ultrafiltration separation membrane materials, and particularly relates to a polyvinylidene fluoride hollow fiber ultrafiltration membrane and a preparation method thereof.
Background
In recent years, China pays high attention to sewage treatment and drinking water health, and ultrafiltration separation membrane materials are more and more favored in sewage treatment and drinking water purification, and the requirements on the performance of the ultrafiltration membrane are higher and higher.
Currently, commercially available ultrafiltration membranes in China and widely applied varieties mainly comprise cellulose acetate ultrafiltration membranes (CA), which have good hydrophilicity but poor strength and cannot meet the application of industrial water treatment; polysulfone ultrafiltration membranes, such as Polyethersulfone (PES) membranes, have good chemical stability and thermal stability, and are widely applied to industries such as household water purification, food and beverage, biomedical treatment and the like, because the mechanical strength of the membranes is not high, the membranes are rarely applied to industrial water treatment; polyolefins such as polypropylene (PP) drawn ultrafiltration membranes and polypropylene (PP) fiber depth filtration membranes. The current commercial membrane has a plurality of configurations such as a flat plate type and a hollow type; polyfluoro, such as polyvinylidene fluoride (PVDF) ultrafiltration membranes. The ultrafiltration membrane has excellent chemical stability, acid resistance, alkali resistance, various organic solvents and high mechanical strength, and is very suitable for industrial sewage treatment and drinking water purification.
Patent CN103111189A discloses a high-flux polyvinylidene fluoride hollow fiber membrane, which is prepared into a membrane section with a double-row finger-shaped hole structure by adopting a dry-wet spinning process, but does not disclose a microstructure scanning electron microscope picture. US6074718 discloses a vinylidene fluoride hollow fiber membrane having a finger-like pore structure extending through the entire cross-section and a method for preparing the same. The above-disclosed membrane sections all have finger-shaped pore structures, so that the mechanical properties of the membrane are greatly reduced; in addition, the separation layers are all on the surface of the membrane, and the separation effect of the membrane is easily affected by scratch or scratch of foreign objects in the manufacturing or using process of the membrane device.
Disclosure of Invention
Aiming at the problems in the prior art, the invention aims to design and provide a polyvinylidene fluoride hollow fiber ultrafiltration membrane and a technical scheme of a preparation method thereof, micropores on the section of the membrane are in a completely asymmetric sponge shape and have no large cavity, the micropores are uniformly distributed on the inner surface and the outer surface, a separation layer is arranged in the middle of the membrane, the pore diameter of the micropores from the middle to the two ends of the membrane layer is gradually increased, the separation effect is not easily influenced by scratching or scraping in use, and the sponge pore structure of the section effectively improves the strength of the membrane; the spinning process is easy to control, good in film performance repeatability and convenient for large-scale production.
The polyvinylidene fluoride hollow fiber ultrafiltration membrane comprises an inner membrane surface layer and an outer membrane surface layer, and is characterized in that micropores are distributed on the inner membrane surface layer and the outer membrane surface layer; the middle part of the membrane is a compact separation layer, and the average pore diameter is 0.01-0.03 mu m; the aperture of the micropores gradually increases from the middle part to the two ends of the membrane layer, and the average aperture of the micropores on the two sides of the compact separation layer (3) is 0.03-0.2 μm.
The polyvinylidene fluoride hollow fiber ultrafiltration membrane is characterized in that micropores on the section of the ultrafiltration membrane are completely asymmetric sponge-shaped without large cavities, and the porosity of the membrane is more than or equal to 85%.
The polyvinylidene fluoride hollow fiber ultrafiltration membrane is characterized in that the thickness of the inner surface layer and the outer surface layer of the membrane is 50-80 μm.
The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane is characterized by comprising the following steps:
1) adding 16-24% of polyvinylidene fluoride, 5-20% of thickening agent, 10-25% of pore-forming agent, 1-3% of hydrophilic modifier and 40-65% of organic solvent in percentage by mass into a stirring tank, stirring for 11-13 hours at 65-75 ℃, filtering and defoaming in vacuum for 11-13 hours to obtain a membrane casting solution;
the thickening agent is one or two of polyvinylpyrrolidone, polyoxyethylene, polyurethane and hydroxyethyl cellulose;
the pore-forming agent is one or two of ethanol, glycol, polyethylene glycol, polyvinyl alcohol, diethylene glycol and glycerol;
the hydrophilic modifier is one or two of sulfonated polyvinylidene fluoride, cellulose diacetate, polyoxyethylene polyoxypropylene ether block copolymer and modified chitosan;
the organic solvent is one or two of triethyl phosphate, dimethylformamide, dimethylacetamide, dimethyl sulfoxide and N-methyl pyrrolidone;
2) mixing a pore-foaming agent or water with an organic solvent to obtain a spinning core solution;
3) extruding the casting solution and the spinning core solution at the temperature of 55-65 ℃ through a spinning nozzle to prepare a hollow fiber membrane;
4) passing through a water vapor section with humidity of 80-100% and temperature of 50-70 deg.C, staying for 0.5-1s, soaking in rinsing water tank after vapor and immersion precipitation, and air drying to obtain the final product.
The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane is characterized in that the polyvinylidene fluoride hollow fiber ultrafiltration membrane in the step 1) comprises the following raw materials in percentage by mass: 18-22% of polyvinylidene fluoride, 10-15% of thickening agent, 15-20% of pore-forming agent, 1.5-2.5% of hydrophilic modifier and 50-55% of organic solvent.
The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane is characterized in that in the step 1): the stirring temperature is 70-72 ℃, the stirring time is 12 hours, and the vacuum defoaming time is 12 hours.
The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane is characterized in that in the step 3): the temperature of the casting film liquid is 60-62 ℃.
The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane is characterized in that in the step 4): the humidity of the water vapor section is 85-95%, the temperature is 55-65 ℃, and the retention time is 0.6-0.9 s.
The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane is characterized in that in the step 4): the humidity of the water vapor section is 90-92%, the temperature is 60-62 ℃, and the retention time is 0.7-0.8 s.
The section micropores of the polyvinylidene fluoride hollow fiber ultrafiltration membrane are in a complete asymmetric sponge shape without large cavities, the micropores are uniformly distributed on the inner surface and the outer surface, the middle part of the membrane is a separation layer, and the average pore diameter is 0.01-0.03 mu m; the aperture of the micropores gradually increases from the middle part to the two ends of the membrane layer, and the average aperture of the micropores at the two sides of the separation layer is 0.03-0.2 μm; the membrane separation layer is positioned in the middle of the membrane section and is protected by two ends of the membrane, so that the separation effect is not easily influenced by scratching or scraping in use; the sponge pore structure of the cross section effectively improves the strength of the membrane.
Drawings
FIG. 1 is a photograph of the outer surface of a film of the present invention;
FIG. 2 is a photograph of the inner surface of the film of the present invention;
FIG. 3 is a photograph of a cross section of a membrane of the present invention;
in the figure: 1-membrane inner surface layer, 2-membrane outer surface layer and 3-compact separation layer.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention and the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following described embodiments are exemplary and are intended to be illustrative of the invention and are not to be construed as limiting the invention.
The polyvinylidene fluoride hollow fiber ultrafiltration membrane comprises an inner membrane surface layer 1 and an outer membrane surface layer 2, wherein micropores are distributed on the inner membrane surface layer 1 and the outer membrane surface layer 2; the middle part of the membrane is a compact separation layer 3, and the average pore diameter is 0.01-0.03 mu m; the aperture of the micropores gradually increases from the middle part to the two ends of the membrane layer, and the average aperture of the micropores at the two sides of the compact separation layer 3 is 0.03-0.2 μm. The section micropores of the ultrafiltration membrane are completely asymmetric sponge-shaped, have no large cavity, and the porosity of the membrane is more than or equal to 85 percent. The thickness of the inner surface layer 1 and the outer surface layer 2 is 50 to 80 μm, preferably 60 to 70 μm.
The hollow fiber ultrafiltration membrane was prepared by the methods of the following examples.
Example 1: adding 18 mass percent of polyvinylidene fluoride (Suwei 6010), 10 mass percent of polyethylene glycol, 13 mass percent of polyvinylpyrrolidone K-15, 1 mass percent of polyoxyethylene-polyoxypropylene block copolymer F127, 40 mass percent of N, N-dimethylformamide and 18 mass percent of N, N-dimethylacetamide into a stirring tank, stirring for 13 hours at the temperature of 65 ℃, filtering, and defoaming in vacuum for 13 hours to obtain the casting solution. And extruding the casting solution at the temperature of 60 ℃, the mixed core solution of 60 percent of water and 40 percent of dimethylformamide by weight percent through a spinning nozzle to obtain the hollow fiber membrane. Passing through a water vapor section with humidity of 85-90% and temperature of 50-60 deg.C, staying for 0.5-1s, soaking in rinsing water tank after vapor and immersion precipitation, and air drying to obtain the final product. The outer surface of the obtained membrane is uniformly distributed with a large number of micropores with the pore diameter of 0.1-0.2 (figure 1), the pore diameter of the micropores distributed on the inner surface of the obtained membrane is far larger than that of the outer surface, and the filtration resistance of the membrane is reduced (figure 2); the section is a dense separation layer with a cross section of about 50 μm from top to bottom, and the section has no cavity and has an asymmetric full-sponge structure (figure 3). The results of the performance tests are shown in table 1 below:
example 2: adding 20 mass percent of polyvinylidene fluoride (Suwei 6010), 6 mass percent of diethylene glycol, 11 mass percent of polyvinylpyrrolidone K-17, 1 mass percent of polyoxyethylene-polyoxypropylene segmented copolymer F127, 40 mass percent of N, N-dimethylformamide and 22 mass percent of N, N-dimethylacetamide into a stirring tank, stirring for 12 hours at the temperature of 70 ℃, filtering, and defoaming in vacuum for 12 hours to obtain the casting solution. And extruding the casting solution at the temperature of 60 ℃ and the mixed core solution of 95 percent by weight of polyethylene glycol and 5 percent by weight of dimethylformamide through a spinning nozzle to obtain the hollow fiber membrane. Passing through a water vapor section with humidity of 85-90% and temperature of 50-60 deg.C, staying for 1-1.5s, immersing in rinsing water tank after vapor and immersion precipitation, and air drying to obtain the final product. The outer surface of the obtained membrane is uniformly distributed with a large number of micropores with the pore diameter of 0.1-0.2, the section of the membrane is a compact separation layer from the top to the bottom with about 60 mu m, and the section of the membrane has no cavity and has a complete asymmetric sponge structure. The results of the performance tests are shown in table 2 below:
example 3: adding 22 mass percent of polyvinylidene fluoride (Suwei 6010), 10 mass percent of polyethylene glycol, 8 mass percent of polyvinylpyrrolidone K-30, 2 mass percent of sulfonated polyvinylidene fluoride, 40 mass percent of N, N-dimethylformamide and 18 mass percent of N, N-dimethylacetamide into a stirring tank, stirring for 11 hours at the temperature of 75 ℃, filtering, and defoaming in vacuum for 11 hours to obtain the casting solution. And extruding the casting solution at the temperature of 60 ℃ and the mixed core solution of 95 percent by weight of polyethylene glycol and 5 percent by weight of dimethylformamide through a spinning nozzle to obtain the hollow fiber membrane. Passing through a water vapor section with humidity of 85-90% and temperature of 60-70 deg.C, staying for 1-2s, immersing in rinsing water tank after vapor and immersion precipitation, and air drying to obtain polyvinylidene fluoride hollow fiber ultrafiltration membrane. The outer surface of the obtained membrane is uniformly distributed with a large number of micropores with the pore diameter of 0.1-0.2, the section of the membrane is a compact separation layer from top to bottom at about 70 mu m, the section of the membrane has no cavity, and the membrane has a complete asymmetric sponge body structure. The results of the performance tests are shown in table 3 below:
example 4: adding 18 mass percent of polyvinylidene fluoride (Suwei 6010), 16 mass percent of polyethylene glycol, 8 mass percent of polyvinylpyrrolidone K-30, 2 mass percent of polyoxyethylene-polyoxypropylene block copolymer F127, 36 mass percent of N, N-dimethylformamide and 18 mass percent of N, N-dimethylacetamide into a stirring tank, stirring for 12 hours at the temperature of 70 ℃, filtering, and defoaming in vacuum for 12 hours to obtain the casting solution. And extruding the casting solution at the temperature of 60 ℃ and the mixed core solution of 95 percent by weight of polyethylene glycol and 5 percent by weight of dimethylformamide through a spinning nozzle to obtain the hollow fiber membrane. Passing through a water vapor section with the humidity of 90-100% and the temperature of 50-60 ℃ and the retention time of 0.5-1s, immersing into a rinsing water tank after vapor and immersion precipitation, and finally airing to prepare the polyvinylidene fluoride hollow fiber ultrafiltration membrane. The outer surface of the obtained membrane is uniformly distributed with a large number of micropores with the pore diameter of 0.1-0.2, the section of the membrane is a compact separation layer from top to bottom at about 65 mu m, the section of the membrane has no cavity, and the membrane has a complete asymmetric sponge body structure. The results of the performance tests are shown in table 4 below:
the influence of the air atmosphere of the invention on the film performance and structure: by controlling the temperature and humidity to be constant, the stability of the membrane performance can be greatly improved. Controlling the humidity to be 80-100%, so that the outer surface of the membrane can be fully exposed in a hot water vapor atmosphere, and the hot water vapor enters the surface of the membrane to induce phase separation to form a large number of outer surface micropores; and the air atmosphere is stably controlled at 50-70 ℃, so that the spinning solution can generate sufficient liquid-liquid phase separation in an air section, the cross section holes are sufficiently grown, a loose sponge hole structure is formed, and the filtration flux is increased.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical scope of the present invention and the equivalent alternatives or modifications according to the technical solution and the inventive concept of the present invention within the technical scope of the present invention.
Claims (9)
1. A polyvinylidene fluoride hollow fiber ultrafiltration membrane comprises an inner membrane surface layer (1) and an outer membrane surface layer (2), and is characterized in that micropores are distributed on the inner membrane surface layer (1) and the outer membrane surface layer (2); the middle part of the membrane is a compact separation layer (3), and the average pore diameter is 0.01-0.03 mu m; the aperture of the micropores gradually increases from the middle part to the two ends of the membrane layer, and the average aperture of the micropores on the two sides of the compact separation layer (3) is 0.03-0.2 μm.
2. The polyvinylidene fluoride hollow fiber ultrafiltration membrane of claim 1, wherein the section micropores of the ultrafiltration membrane are completely asymmetric sponge-like without large cavities, and the porosity of the membrane is not less than 85%.
3. A polyvinylidene fluoride hollow fiber ultrafiltration membrane according to claim 1, wherein the thickness of the inner membrane inner surface layer (1) and the outer membrane surface layer (2) is 50 to 80 μm.
4. The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane of claim 1, characterized by comprising the following steps:
1) adding 16-24% of polyvinylidene fluoride, 5-20% of thickening agent, 10-25% of pore-forming agent, 1-3% of hydrophilic modifier and 40-65% of organic solvent in percentage by mass into a stirring tank, stirring for 11-13 hours at 65-75 ℃, filtering and defoaming in vacuum for 11-13 hours to obtain a membrane casting solution;
the thickening agent is one or two of polyvinylpyrrolidone, polyoxyethylene, polyurethane and hydroxyethyl cellulose;
the pore-forming agent is one or two of ethanol, glycol, polyethylene glycol, polyvinyl alcohol, diethylene glycol and glycerol;
the hydrophilic modifier is one or two of sulfonated polyvinylidene fluoride, cellulose diacetate, polyoxyethylene polyoxypropylene ether block copolymer and modified chitosan;
the organic solvent is one or two of triethyl phosphate, dimethylformamide, dimethylacetamide, dimethyl sulfoxide and N-methyl pyrrolidone;
2) mixing a pore-foaming agent or water with an organic solvent to obtain a spinning core solution;
3) extruding the casting solution and the spinning core solution at the temperature of 55-65 ℃ through a spinning nozzle to prepare a hollow fiber membrane;
4) passing through a water vapor section with humidity of 80-100% and temperature of 50-70 deg.C, staying for 0.5-1s, soaking in rinsing water tank after vapor and immersion precipitation, and air drying to obtain the final product.
5. The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane of claim 4, wherein the raw materials in the step 1) are respectively as follows by mass percent: 18-22% of polyvinylidene fluoride, 10-15% of thickening agent, 15-20% of pore-forming agent, 1.5-2.5% of hydrophilic modifier and 50-55% of organic solvent.
6. The method for preparing a polyvinylidene fluoride hollow fiber ultrafiltration membrane of claim 4, wherein in step 1): the stirring temperature is 70-72 ℃, the stirring time is 12 hours, and the vacuum defoaming time is 12 hours.
7. The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane of claim 4, characterized in that in step 3): the temperature of the casting film liquid is 60-62 ℃.
8. The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane of claim 4, characterized in that in step 4): the humidity of the water vapor section is 85-95%, the temperature is 55-65 ℃, and the retention time is 0.6-0.9 s.
9. The preparation method of the polyvinylidene fluoride hollow fiber ultrafiltration membrane of claim 4, characterized in that in step 4): the humidity of the water vapor section is 90-92%, the temperature is 60-62 ℃, and the retention time is 0.7-0.8 s.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114130202A (en) * | 2021-12-15 | 2022-03-04 | 中国科学院长春应用化学研究所 | Microporous filter membrane and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010094670A (en) * | 2008-09-19 | 2010-04-30 | Toray Ind Inc | Polyvinylidene fluoride-based multiple membrane and method for producing the same |
| CN106474943A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | Hollow fiber ultrafiltration membrane |
| CN107413205A (en) * | 2017-09-09 | 2017-12-01 | 威海威高血液净化制品有限公司 | Dialysis effluent purifying hollow-fibre membrane and its processing method |
| CN109012194A (en) * | 2018-09-17 | 2018-12-18 | 杭州汉膜新材料科技有限公司 | A kind of Polyethersulfone Hollow Fiber Plasma microporous barrier and preparation method |
| CN111530304A (en) * | 2020-04-28 | 2020-08-14 | 北京赛诺膜技术有限公司 | Large-flux virus-removing polyvinylidene fluoride hollow fiber microporous membrane and preparation method thereof |
-
2021
- 2021-07-16 CN CN202110805244.7A patent/CN113457465A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010094670A (en) * | 2008-09-19 | 2010-04-30 | Toray Ind Inc | Polyvinylidene fluoride-based multiple membrane and method for producing the same |
| CN106474943A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | Hollow fiber ultrafiltration membrane |
| CN107413205A (en) * | 2017-09-09 | 2017-12-01 | 威海威高血液净化制品有限公司 | Dialysis effluent purifying hollow-fibre membrane and its processing method |
| CN109012194A (en) * | 2018-09-17 | 2018-12-18 | 杭州汉膜新材料科技有限公司 | A kind of Polyethersulfone Hollow Fiber Plasma microporous barrier and preparation method |
| CN111530304A (en) * | 2020-04-28 | 2020-08-14 | 北京赛诺膜技术有限公司 | Large-flux virus-removing polyvinylidene fluoride hollow fiber microporous membrane and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 杨铁军: "《产业专利分析报告（第37册）—高性能膜材料》", 30 June 2015, 知识产权出版社 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114130202A (en) * | 2021-12-15 | 2022-03-04 | 中国科学院长春应用化学研究所 | Microporous filter membrane and preparation method thereof |
| CN114130202B (en) * | 2021-12-15 | 2023-03-14 | 中国科学院长春应用化学研究所 | Microporous filter membrane and preparation method thereof |
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