CN110605032A - Preparation method of finishing type hollow fiber membrane - Google Patents
Preparation method of finishing type hollow fiber membrane Download PDFInfo
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- CN110605032A CN110605032A CN201810624292.4A CN201810624292A CN110605032A CN 110605032 A CN110605032 A CN 110605032A CN 201810624292 A CN201810624292 A CN 201810624292A CN 110605032 A CN110605032 A CN 110605032A
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- fiber membrane
- hollow fiber
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
- B01D67/0009—Organic membrane manufacture by phase separation, sol-gel transition, evaporation or solvent quenching
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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
- B01D69/082—Hollow fibre membranes characterised by the cross-sectional shape of the fibre
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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
- B01D69/087—Details relating to the spinning process
- B01D69/088—Co-extrusion; Co-spinning
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- 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
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- Chemical Kinetics & Catalysis (AREA)
- Dispersion Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Artificial Filaments (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention relates to the technical field of preparation of hollow fiber membranes, in particular to a preparation method of a finish type hollow fiber membrane. The pure water flux of the finished hollow fiber membrane prepared by the method is reduced compared with that of a single-core membrane, but the tensile stress of the finished hollow fiber membrane is doubled compared with that of the single-core membrane. In the practical application process, the finishing hollow fiber membrane is not easy to flatten under high pressure, can keep relatively larger flux, is not easy to break, can greatly improve the application field and the application range, can reduce the maintenance and replacement cost of the product, and prolongs the service life. In addition, the preparation method of the finishing hollow fiber membrane has simple process, improves the mechanical strength of the hollow fiber membrane, reduces the loss of raw materials, improves the production efficiency of the finishing hollow fiber membrane, reduces the cost, has good water permeability, and is suitable for popularization and use.
Description
Technical Field
The invention relates to the technical field of preparation of hollow fiber membranes, in particular to a preparation method of a finish type hollow fiber membrane.
Background
In the actual production process of the hollow fiber membrane, in order to improve the production efficiency of enterprises, almost all enterprises adopt a single-hole spinneret combination or a multi-hole parallel mode. Problems with this spinneret are: (1) the disassembly, the assembly and the cleaning are difficult; (2) the waste of raw materials is large; (3) difficult to repair after damage; (4) the problem of uneven filament output exists. The single-hole hollow fiber membrane has low strength, and the condition of yarn breakage is easy to occur in use. To solve this problem, lining/fascia has begun to appear, inorganic materials are added to the formulation to increase the self-supporting strength of the membrane filaments, membrane solutions are coated on non-woven fabrics or woven tubes to achieve reinforcement, and porous tubular membranes are prepared. Problems with these membrane materials: (1) the lining/reinforced film is easy to fall off and peel off; (2) easily dissolved out to form a cavity; (3) the preparation process of the inorganic tubular membrane is complicated, the operation is difficult, the price is high, the water permeability is poor, and the practicability is not high.
The invention relates to a method for preparing a terminating hollow fiber membrane, which is characterized in that the pure water flux of the terminating hollow fiber membrane prepared by the method is reduced compared with that of a single-core membrane, but the tensile stress of the terminating hollow fiber membrane is doubled compared with that of the single-core membrane. In the practical application process, the finishing hollow fiber membrane is not easy to flatten under high pressure, can keep relatively larger flux, is not easy to break, can greatly improve the application field and the application range, can reduce the maintenance and replacement cost of the product, and prolongs the service life. In addition, the preparation method of the finishing hollow fiber membrane has simple process, improves the mechanical strength of the hollow fiber membrane, reduces the loss of raw materials, improves the production efficiency of the finishing hollow fiber membrane, reduces the cost, has good water permeability, and is suitable for popularization and use.
Disclosure of Invention
In order to overcome the defects in the background art, the technical scheme adopted by the invention for solving the technical problems is as follows: a preparation method of a finishing type hollow fiber membrane is characterized by comprising the following steps: the following components are counted by weight portion,
(1) selecting a high polymer material: 10-20 parts; additive: 1-10 parts; mixing solvent: 60-80 parts; drying the high molecular material and the additive
Heating and drying in a box, and removing water from the mixed solvent by using an activated molecular sieve;
(2) dissolving a high polymer material and an additive in a mixed solvent, heating a mixture consisting of the high polymer material, the additive and the mixed solvent to a molten state, and stirring to form a casting solution;
(3) extruding the casting solution prepared in the step (2) through a quincunx spinneret, then cooling the extruded casting solution in a solidification solution to carry out phase inversion, carrying out post-treatment of hole protection on the phase-inverted fiber membrane, and airing the membrane for 2-5 days at room temperature until the membrane is completely dried, thereby forming the finished hollow fiber membrane;
the high polymer material is polyether sulfone, polyethylene, polypropylene, polytetrafluoroethylene, polyacrylonitrile, polyvinyl chloride, polyimide or polyvinylidene fluoride; the additive is one or more of absolute ethyl alcohol, polyethylene glycol, lithium nitrate and polyvinylpyrrolidone; the mixed solvent comprises two or more than two of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, acetone, tetrahydrofuran and triethyl phosphate.
Preferably, the component in the coagulation solution in the step (3) includes at least one of N-methylpyrrolidone, water, ethanol, glycerol, heptane, and pentane.
Preferably, the temperature of the solidification solution in the step (3) is 10-100 ℃.
Preferably, the temperature of the solidification solution in the step (3) is 30-80 ℃.
Preferably, the finishing type hollow fiber membrane extruded from the quincunx spinneret in the step (3) is soaked in the coagulation solution for 20 to 50 hours.
Preferably, in the step (3), the post-treatment of the fiber membrane after pore protection is completed by soaking in a mixed solution of glycerol and water, wherein the volume ratio of glycerol to water in the mixed solution of glycerol and water is 0.2-2.
Preferably, the fiber membrane is soaked in the mixed solution of glycerol and water for 20 to 40 hours after being subjected to pore preservation.
The invention relates to a method for preparing a terminating hollow fiber membrane, which is characterized in that the pure water flux of the terminating hollow fiber membrane prepared by the method is reduced compared with that of a single-core membrane, but the tensile stress of the terminating hollow fiber membrane is doubled compared with that of the single-core membrane. In the practical application process, the finishing hollow fiber membrane is not easy to flatten under high pressure, can keep relatively larger flux, is not easy to break, can greatly improve the application field and the application range, can reduce the maintenance and replacement cost of the product, and prolongs the service life. In addition, the preparation method of the finishing hollow fiber membrane has simple process, improves the mechanical strength of the hollow fiber membrane, reduces the loss of raw materials, improves the production efficiency of the finishing hollow fiber membrane, reduces the cost, has good water permeability, and is suitable for popularization and use.
Drawings
The invention is further illustrated with reference to the following figures and examples.
FIG. 1 is an SEM image of the outer surface of a finished hollow fiber membrane prepared in accordance with a second embodiment of the present invention;
FIG. 2 is an SEM image of the inner surface of a finished hollow fiber membrane prepared in accordance with a second embodiment of the present invention;
FIG. 3 is an SEM image of a cross section of a finished hollow fiber membrane prepared in accordance with a second embodiment of the present invention;
FIG. 4 is an SEM image of a cross section of a closed hollow fiber membrane prepared in the second embodiment of the present invention, which is partially enlarged.
Detailed Description
In a specific embodiment, a method for preparing a finishing hollow fiber membrane includes the steps of: the following components are counted by weight portion,
(1) selecting a high polymer material: 10 parts of (A); additive: 1 part; mixing solvent: 60 parts; heating and drying the high polymer material and the additive in an oven, and removing water from the mixed solvent by using an activated molecular sieve;
(2) dissolving a high polymer material and an additive in a mixed solvent, heating a mixture consisting of the high polymer material, the additive and the mixed solvent to a molten state, and stirring to form a casting solution;
(3) extruding the casting solution prepared in the step (2) through a quincunx spinneret, cooling the extruded casting solution in a solidification solution to perform phase inversion, carrying out post-treatment of hole protection on the phase-inverted fiber membrane, and airing the membrane for 2 days at room temperature until the membrane is completely dried, thereby forming the finished hollow fiber membrane;
the high polymer material is polyether sulfone; the additive is absolute ethyl alcohol; the mixed solvent is N, N-dimethylformamide and N, N-dimethylacetamide.
The components in the coagulating solution in the step (3) comprise N-methyl pyrrolidone, the temperature of the coagulating solution in the step (3) is 10 ℃, the temperature of the coagulating solution in the step (3) is 30 ℃, the soaking time of the finished hollow fiber membrane extruded from a quincunx spinneret in the coagulating solution in the step (3) is 20 hours, the post-treatment of the fiber membrane subjected to hole retention in the step (3) is completed by soaking in a mixed solution of glycerol and water, wherein the volume ratio of glycerol to water in the mixed solution of glycerol and water is 0.2:1, and the soaking time of the fiber membrane subjected to hole retention in the mixed solution of glycerol and water is 20 hours.
In the second embodiment, referring to fig. 1-4, a method for preparing a finishing hollow fiber membrane includes the steps of: the following components are counted by weight portion,
(1) selecting a high polymer material: 15 parts of (1); additive: 6 parts of (1); mixing solvent: 70 parts of (B); drying the high molecular material and the additive
Heating and drying in a box, and removing water from the mixed solvent by using an activated molecular sieve;
(2) dissolving a high polymer material and an additive in a mixed solvent, heating a mixture consisting of the high polymer material, the additive and the mixed solvent to a molten state, and stirring to form a casting solution;
(3) extruding the casting solution prepared in the step (2) through a quincunx spinneret, cooling the extruded casting solution in a solidification solution to perform phase inversion, carrying out post-treatment of hole protection on the phase-inverted fiber membrane, and airing the membrane for 4 days at room temperature until the membrane is completely dried, thereby forming the finished hollow fiber membrane;
the high polymer material is polypropylene; the additive is absolute ethyl alcohol and polyethylene glycol; the mixed solvent is N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide and acetone.
The components in the coagulating solution in the step (3) comprise water and ethanol, the temperature of the coagulating solution in the step (3) is 60 ℃, the temperature of the coagulating solution in the step (3) is 50 ℃, the soaking time of the finished hollow fiber membrane extruded from a quincunx spinneret in the coagulating solution in the step (3) is 40 hours, the post-treatment of the fiber membrane subjected to hole retention in the step (3) is completed by soaking in a mixed solution of glycerol and water, wherein the volume ratio of glycerol to water in the mixed solution of glycerol and water is 1, and the soaking time of the fiber membrane subjected to hole retention in the mixed solution of glycerol and water is 30 hours.
As can be seen from FIGS. 1 and 2, the outer surface of the finished hollow fiber membrane forms uniformly distributed and uniform pores with the pore diameter of about 0.06 μm, the surface is smooth and basically free of impurities, and the smooth surface can increase the anti-pollution performance of the membrane to a certain extent; the inner surface is rough, presents certain texture, and the structure is compact, has a small amount of cavities. As can be seen from FIGS. 3 and 4, the cross section of the finished hollow fiber membrane consists of an inner and an outer dense skin layers and a middle teardrop-shaped macroporous support layer structure, and a thin sponge layer like a wall is arranged between teardrop-shaped holes. Dense honeycomb-shaped small holes are distributed in loose finger-shaped holes on the cross section of the membrane, and the structure can further intercept pollutants with smaller specific surface aperture, thereby being beneficial to improving the interception effect of the membrane.
The third concrete embodiment: a preparation method of a finishing hollow fiber membrane comprises the following steps: the following components are counted by weight portion,
(1) selecting a high polymer material: 20 parts of (1); additive: 10 parts of (A); mixing solvent: 80 parts of a mixture; drying the high molecular material and the additive
Heating and drying in a box, and removing water from the mixed solvent by using an activated molecular sieve;
(2) dissolving a high polymer material and an additive in a mixed solvent, heating a mixture consisting of the high polymer material, the additive and the mixed solvent to a molten state, and stirring to form a casting solution;
(3) extruding the casting solution prepared in the step (2) through a quincunx spinneret, cooling the extruded casting solution in a solidification solution to perform phase inversion, carrying out post-treatment of hole protection on the phase-inverted fiber membrane, and airing the membrane for 5 days at room temperature until the membrane is completely dried, thereby forming the finished hollow fiber membrane;
the high polymer material is polytetrafluoroethylene; the additives are polyethylene glycol, lithium nitrate and polyvinylpyrrolidone; the mixed solvent is N-methyl pyrrolidone, dimethyl sulfoxide, acetone and tetrahydrofuran.
The components in the coagulating solution in the step (3) are glycerol, heptane and pentane, the temperature of the coagulating solution in the step (3) is 100 ℃, the temperature of the coagulating solution in the step (3) is 80 ℃, the soaking time of the finished hollow fiber membrane extruded from a quincunx spinneret in the coagulating solution in the step (3) is 50 hours, the post-treatment of the fiber membrane subjected to hole retention in the step (3) is completed by soaking in a mixed solution of glycerol and water, the volume ratio of glycerol to water in the mixed solution of glycerol and water is 2, and the soaking time of the fiber membrane subjected to hole retention in the mixed solution of glycerol and water is 40 hours.
The invention relates to a method for preparing a terminating hollow fiber membrane, which is characterized in that the pure water flux of the terminating hollow fiber membrane prepared by the method is reduced compared with that of a single-core membrane, but the tensile stress of the terminating hollow fiber membrane is doubled compared with that of the single-core membrane. In the practical application process, the finishing hollow fiber membrane is not easy to flatten under high pressure, can keep relatively larger flux, is not easy to break, can greatly improve the application field and the application range, can reduce the maintenance and replacement cost of the product, and prolongs the service life. In addition, the preparation method of the finishing hollow fiber membrane has simple process, improves the mechanical strength of the hollow fiber membrane, reduces the loss of raw materials, improves the production efficiency of the finishing hollow fiber membrane, reduces the cost, has good water permeability, and is suitable for popularization and use.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.
Claims (7)
1. A preparation method of a finishing type hollow fiber membrane is characterized by comprising the following steps: the following components are counted by weight portion,
(1) selecting a high polymer material: 10-20 parts; additive: 1-10 parts; mixing solvent: 60-80 parts; heating and drying the high polymer material and the additive in an oven, and removing water from the mixed solvent by using an activated molecular sieve;
(2) dissolving a high polymer material and an additive in a mixed solvent, heating a mixture consisting of the high polymer material, the additive and the mixed solvent to a molten state, and stirring to form a casting solution;
(3) extruding the casting solution prepared in the step (2) through a quincunx spinneret, then cooling the extruded casting solution in a solidification solution to carry out phase inversion, carrying out post-treatment of hole protection on the phase-inverted fiber membrane, and airing the membrane for 2-5 days at room temperature until the membrane is completely dried, thereby forming the finished hollow fiber membrane;
the high polymer material is polyether sulfone, polyethylene, polypropylene, polytetrafluoroethylene, polyacrylonitrile, polyvinyl chloride, polyimide or polyvinylidene fluoride; the additive is one or more of absolute ethyl alcohol, polyethylene glycol, lithium nitrate and polyvinylpyrrolidone; the mixed solvent comprises two or more than two of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, acetone, tetrahydrofuran and triethyl phosphate.
2. The method of claim 1, wherein the component of the coagulating solution in the step (3) comprises at least one of N-methylpyrrolidone, water, ethanol, glycerol, heptane and pentane.
3. The method for preparing a hollow fiber membrane of claim 1, wherein the temperature of the coagulation solution in the step (3) is 10 to 100 ℃.
4. The method for producing a hollow fiber membrane of a dead end type according to claim 1 or 3, wherein the temperature of the coagulation solution in the step (3) is 30 to 80 ℃.
5. The method of claim 1, wherein the step (3) of immersing the finished hollow fiber membrane extruded from the quincunx spinneret in the coagulation solution is performed for 20 to 50 hours.
6. The method according to claim 1, wherein the step (3) of subjecting the fiber membrane to pore-keeping is performed by soaking the fiber membrane in a mixed solution of glycerol and water, wherein the volume ratio of glycerol to water in the mixed solution of glycerol and water is 0.2-2.
7. The method according to claim 1, wherein the fiber membrane is subjected to pore retention and soaked in a mixed solution of glycerol and water for 20 to 40 hours.
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| CN201810624292.4A CN110605032A (en) | 2018-06-16 | 2018-06-16 | Preparation method of finishing type hollow fiber membrane |
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| CN201810624292.4A CN110605032A (en) | 2018-06-16 | 2018-06-16 | Preparation method of finishing type hollow fiber membrane |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101138706A (en) * | 2006-09-04 | 2008-03-12 | 胡萍 | Bunchiness hollow fiber film and method of preparing the same |
| CN101396642A (en) * | 2008-10-24 | 2009-04-01 | 东华大学 | Antibiotic hollow fiber separation film and preparation method thereof |
| CN101856596A (en) * | 2010-06-12 | 2010-10-13 | 郑州大学 | Antibacterial polysulfone hollow fiber ultrafiltration membrane |
| CN101890308A (en) * | 2010-04-23 | 2010-11-24 | 苏州膜华材料科技有限公司 | External compression type hollow fiber ultrafiltration membrane and preparation method |
| CN102430344A (en) * | 2011-11-07 | 2012-05-02 | 东华大学 | Hollow polyvinylidene fluoride fibrous membrane and preparation method as well as application thereof |
| CN104607056A (en) * | 2015-02-03 | 2015-05-13 | 贺攀 | Hollow fiber compound nanofiltration membrane and preparation method thereof |
-
2018
- 2018-06-16 CN CN201810624292.4A patent/CN110605032A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101138706A (en) * | 2006-09-04 | 2008-03-12 | 胡萍 | Bunchiness hollow fiber film and method of preparing the same |
| CN101396642A (en) * | 2008-10-24 | 2009-04-01 | 东华大学 | Antibiotic hollow fiber separation film and preparation method thereof |
| CN101890308A (en) * | 2010-04-23 | 2010-11-24 | 苏州膜华材料科技有限公司 | External compression type hollow fiber ultrafiltration membrane and preparation method |
| CN101856596A (en) * | 2010-06-12 | 2010-10-13 | 郑州大学 | Antibacterial polysulfone hollow fiber ultrafiltration membrane |
| CN102430344A (en) * | 2011-11-07 | 2012-05-02 | 东华大学 | Hollow polyvinylidene fluoride fibrous membrane and preparation method as well as application thereof |
| CN104607056A (en) * | 2015-02-03 | 2015-05-13 | 贺攀 | Hollow fiber compound nanofiltration membrane and preparation method thereof |
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