CN112844071A - Preparation method of hollow fiber oxygen-enriched membrane - Google Patents
Preparation method of hollow fiber oxygen-enriched membrane Download PDFInfo
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- CN112844071A CN112844071A CN202011550616.8A CN202011550616A CN112844071A CN 112844071 A CN112844071 A CN 112844071A CN 202011550616 A CN202011550616 A CN 202011550616A CN 112844071 A CN112844071 A CN 112844071A
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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
- 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
- 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
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
- C01B13/02—Preparation of oxygen
- C01B13/0229—Purification or separation processes
- C01B13/0248—Physical processing only
- C01B13/0251—Physical processing only by making use of membranes
- C01B13/0255—Physical processing only by making use of membranes characterised by the type of membrane
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/08—Specific temperatures applied
-
- 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
- B01D2325/24—Mechanical properties, e.g. strength
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/28—Degradation or stability over time
-
- 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
Abstract
The invention relates to the technical field of membrane separation, and discloses a preparation method of a hollow fiber oxygen-enriched membrane, which comprises the following raw materials in parts by weight: 25% -40% of polyvinylidene fluoride, 5% -10% of polysulfone, 35% -40% of organic solvent, 8% -10% of ethyl orthosilicate, 4% -7% of additive, 2% -4% of amphiphilic copolymer, 2% -6% of nano particles, 4% -8% of meta-aramid fiber, 6% -10% of pore-forming agent and 4% -8% of glass fiber. According to the preparation method for the hollow fiber oxygen-enriched membrane, the ethyl orthosilicate is added, a compact membrane is convenient to form on the outer surface of the hollow fiber base membrane, the anti-peeling strength of the ultrafiltration membrane is high, the polysulfone is added, the high temperature resistance of the base membrane is convenient to improve, the nanoparticles, the meta-aramid fiber and the glass fiber are added, the strength of the base membrane is convenient to improve, the excellent temperature resistance is achieved, the mechanical strength of the ultrafiltration membrane is enhanced, meanwhile, the meta-aramid fiber has excellent hydrophilic performance, the hydrophilic performance of the obtained hollow fiber ultrafiltration membrane can be improved, and the obtained anti-pollution performance is good.
Description
Technical Field
The invention relates to the technical field of membrane separation, in particular to a preparation method for a hollow fiber oxygen-enriched membrane.
Background
The membrane separation technology is widely used in chemical, electronic, medical and biological engineering industries, one of which is for "oxygen generation", and the principle is that oxygen with high oxygen concentration is collected and generated by utilizing different speeds of oxygen, nitrogen and other components in air passing through a membrane.
At present, the oxygen enrichment principle of the membrane oxygen enrichment technology is as follows: the membrane oxygen enrichment is to utilize different permeation rates of components in air when permeating a membrane, under the driving of pressure difference, oxygen in the air preferentially passes through the membrane to obtain oxygen-enriched air, however, the existing membrane body structure is easily polluted in the filtering process, so that the filtering effect is reduced, the service life is shortened, meanwhile, the mechanical strength is poor, and the conditions of breakage and corrosion are easy to occur, so that the preparation method for the hollow fiber oxygen-enriched membrane is provided to solve the problems.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a preparation method for a hollow fiber oxygen-enriched membrane, which has the advantages of long service life and the like, and solves the problems that the existing membrane body structure is easy to be polluted in the filtering process, so that the filtering effect is reduced, the service life is shortened, the mechanical strength is poor, and the membrane is easy to damage and corrode.
(II) technical scheme
In order to achieve the purpose of long service life, the invention provides the following technical scheme: a preparation method for a hollow fiber oxygen-enriched membrane comprises the following raw materials in parts by weight: 25% -40% of polyvinylidene fluoride, 5% -10% of polysulfone, 35% -40% of organic solvent, 8% -10% of ethyl orthosilicate, 4% -7% of additive, 2% -4% of amphiphilic copolymer, 2% -6% of nano particles, 4% -8% of meta-aramid fiber, 6% -10% of pore-forming agent and 4% -8% of glass fiber.
Preferably, the pore-forming agent is one or more of polyethylene glycol, polyvinylpyrrolidone, propylene glycol, ethylene glycol monomethyl ether, lithium chloride monohydrate, acetone, ethanol and water, and the additive is one or more of polyvinylpyrrolidone, polyacrylic acid, polyethylene glycol, polyvinyl alcohol, lithium chloride, sodium chloride, calcium chloride, lithium nitrate or formamide.
Preferably, the organic solvent is absolute ethyl alcohol, and the amphiphilic copolymer is poly (methyl methacrylate-vinyl alcohol).
Another technical problem to be solved by the present invention is to provide a method for preparing a hollow fiber oxygen-enriched membrane, comprising the following steps:
1) dissolving dried polyvinylidene fluoride, polysulfone, nano particles, meta-aramid fiber, pore-forming agent and glass fiber in an organic solvent, and mixing and stirring until the materials are completely dissolved for later use;
2) putting ethyl orthosilicate into the organic solvent prepared in the step 1), and stirring until the ethyl orthosilicate is completely dissolved for later use;
3) placing the solution in the step 2) at a certain temperature, adding an additive and an amphiphilic copolymer, stirring and defoaming by using a magnetic stirrer, wherein the stirring time is 5-6 h, the defoaming time is 24-48h, and the defoaming temperature is 40-80 ℃ for later use;
4) feeding the mixed solution prepared in the step 3) into a spinning machine, extruding the mixed solution by a spinning nozzle to form hollow fibers, standing until part of solvent in the fibers is evaporated, immersing the fibers into an aqueous solution for solidification, and finally performing surface treatment at the solidification temperature of 5-20 ℃ to form the oxygen-enriched membrane.
(III) advantageous effects
Compared with the prior art, the invention provides a preparation method for a hollow fiber oxygen-enriched membrane, which has the following beneficial effects:
according to the preparation method for the hollow fiber oxygen-enriched membrane, the ethyl orthosilicate is added, a compact membrane is convenient to form on the outer surface of the hollow fiber base membrane, the anti-peeling strength of the ultrafiltration membrane is high, the polysulfone is added, the high temperature resistance of the base membrane is convenient to improve, the nanoparticles, the meta-aramid fiber and the glass fiber are added, the strength of the base membrane is convenient to improve, the excellent temperature resistance is achieved, the mechanical strength of the ultrafiltration membrane is enhanced, meanwhile, the meta-aramid fiber has excellent hydrophilic performance, the hydrophilic performance of the obtained hollow fiber ultrafiltration membrane can be improved, the anti-pollution performance is good, and the purpose of long service life is achieved.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, 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. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The first embodiment is as follows:
a preparation method for a hollow fiber oxygen-enriched membrane comprises the following raw materials in parts by weight: 25% of polyvinylidene fluoride, 5% of polysulfone, 35% of an organic solvent, 8% of ethyl orthosilicate, 4% of an additive, 2% of an amphiphilic copolymer, 2% of nanoparticles, 4% of meta-aramid fibers, 6% of a pore-forming agent and 4% of glass fibers.
A preparation method for a hollow fiber oxygen-enriched membrane comprises the following steps:
1) dissolving 25% of dried polyvinylidene fluoride, 5% of polysulfone, 2% of nano particles, 4% of meta-aramid fiber, 6% of pore-forming agent and 4% of glass fiber in 35% of organic solvent, and mixing and stirring until the materials are completely dissolved for later use;
2) putting 8% of tetraethoxysilane into the organic solvent for later use in the step 1), and stirring until the tetraethoxysilane is completely dissolved for later use;
3) placing the solution in the step 2) at a certain temperature, adding 4% of additive and 2% of amphiphilic copolymer, stirring and defoaming by using a magnetic stirrer, wherein the stirring time is 5-6 h, the defoaming time is 24-48h, and the defoaming temperature is 40-80 ℃ for later use;
4) feeding the mixed solution prepared in the step 3) into a spinning machine, extruding the mixed solution by a spinning nozzle to form hollow fibers, standing until part of solvent in the fibers is evaporated, immersing the fibers into an aqueous solution for solidification, and finally performing surface treatment at the solidification temperature of 5-20 ℃ to form the oxygen-enriched membrane.
Example two:
a preparation method for a hollow fiber oxygen-enriched membrane comprises the following raw materials in parts by weight: 32% of polyvinylidene fluoride, 7% of polysulfone, 37% of an organic solvent, 9% of ethyl orthosilicate, 5% of an additive, 3% of an amphiphilic copolymer, 4% of nano particles, 6% of meta-aramid fibers, 8% of a pore-forming agent and 6% of glass fibers.
A preparation method for a hollow fiber oxygen-enriched membrane comprises the following steps:
1) dissolving 32% of dried polyvinylidene fluoride, 7% of polysulfone, 4% of nano particles, 6% of meta-aramid fiber, 8% of pore-forming agent and 6% of glass fiber in 37% of organic solvent, and mixing and stirring until the materials are completely dissolved for later use;
2) putting 9% of tetraethoxysilane into the organic solvent for later use in the step 1), and stirring until the tetraethoxysilane is completely dissolved for later use;
3) placing the solution in the step 2) at a certain temperature, adding 5% of additive and 3% of amphiphilic copolymer, stirring and defoaming by using a magnetic stirrer, wherein the stirring time is 5-6 h, the defoaming time is 24-48h, and the defoaming temperature is 40-80 ℃ for later use;
4) feeding the mixed solution prepared in the step 3) into a spinning machine, extruding the mixed solution by a spinning nozzle to form hollow fibers, standing until part of solvent in the fibers is evaporated, immersing the fibers into an aqueous solution for solidification, and finally performing surface treatment at the solidification temperature of 5-20 ℃ to form the oxygen-enriched membrane.
Example three:
a preparation method for a hollow fiber oxygen-enriched membrane comprises the following raw materials in parts by weight: 40% of polyvinylidene fluoride, 10% of polysulfone, 40% of organic solvent, 10% of ethyl orthosilicate, 7% of additive, 4% of amphiphilic copolymer, 6% of nano-particles, 8% of meta-aramid fiber, 10% of pore-forming agent and 8% of glass fiber.
A preparation method for a hollow fiber oxygen-enriched membrane comprises the following steps:
1) dissolving 40% of dried polyvinylidene fluoride, 10% of polysulfone, 6% of nano particles, 8% of meta-aramid fiber, 10% of pore-forming agent and 8% of glass fiber in 40% of organic solvent, and mixing and stirring until the materials are completely dissolved for later use;
2) putting 10% of tetraethoxysilane into the organic solvent for later use in the step 1), and stirring until the tetraethoxysilane is completely dissolved for later use;
3) placing the solution in the step 2) at a certain temperature, adding 7% of additive and 4% of amphiphilic copolymer, stirring and defoaming by using a magnetic stirrer, wherein the stirring time is 5-6 h, the defoaming time is 24-48h, and the defoaming temperature is 40-80 ℃ for later use;
4) feeding the mixed solution prepared in the step 3) into a spinning machine, extruding the mixed solution by a spinning nozzle to form hollow fibers, standing until part of solvent in the fibers is evaporated, immersing the fibers into an aqueous solution for solidification, and finally performing surface treatment at the solidification temperature of 5-20 ℃ to form the oxygen-enriched membrane.
The invention has the beneficial effects that: according to the preparation method for the hollow fiber oxygen-enriched membrane, the ethyl orthosilicate is added, a compact membrane is convenient to form on the outer surface of the hollow fiber base membrane, the anti-peeling strength of the ultrafiltration membrane is high, the polysulfone is added, the high temperature resistance of the base membrane is convenient to improve, the nanoparticles, the meta-aramid fiber and the glass fiber are added, the strength of the base membrane is convenient to improve, the excellent temperature resistance is achieved, the mechanical strength of the ultrafiltration membrane is enhanced, meanwhile, the meta-aramid fiber has excellent hydrophilic performance, the hydrophilic performance of the obtained hollow fiber ultrafiltration membrane can be improved, the anti-pollution performance is good, and the purpose of long service life is achieved.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (7)
1. The preparation method for the hollow fiber oxygen-enriched membrane is characterized by comprising the following raw materials in parts by weight: 25% -40% of polyvinylidene fluoride, 5% -10% of polysulfone, 35% -40% of organic solvent, 8% -10% of ethyl orthosilicate, 4% -7% of additive, 2% -4% of amphiphilic copolymer, 2% -6% of nano particles, 4% -8% of meta-aramid fiber, 6% -10% of pore-forming agent and 4% -8% of glass fiber.
2. The method according to claim 1, wherein the pore-forming agent is one or more of polyethylene glycol, polyvinylpyrrolidone, propylene glycol, ethylene glycol methyl ether, lithium chloride monohydrate, acetone, ethanol and water, and the additive is one or more of polyvinylpyrrolidone, polyacrylic acid, polyethylene glycol, polyvinyl alcohol, lithium chloride, sodium chloride, calcium chloride, lithium nitrate and formamide.
3. The method as claimed in claim 1, wherein the organic solvent is absolute ethanol, and the amphiphilic copolymer is poly (methyl methacrylate-vinyl alcohol).
4. The preparation method of the hollow fiber oxygen-enriched membrane according to claim 1, which is characterized by comprising the following raw materials in parts by weight: 25% of polyvinylidene fluoride, 5% of polysulfone, 35% of an organic solvent, 8% of ethyl orthosilicate, 4% of an additive, 2% of an amphiphilic copolymer, 2% of nanoparticles, 4% of meta-aramid fibers, 6% of a pore-forming agent and 4% of glass fibers.
5. The preparation method of the hollow fiber oxygen-enriched membrane according to claim 1, which is characterized by comprising the following raw materials in parts by weight: 32% of polyvinylidene fluoride, 7% of polysulfone, 37% of an organic solvent, 9% of ethyl orthosilicate, 5% of an additive, 3% of an amphiphilic copolymer, 4% of nano particles, 6% of meta-aramid fibers, 8% of a pore-forming agent and 6% of glass fibers.
6. The preparation method of the hollow fiber oxygen-enriched membrane according to claim 1, which is characterized by comprising the following raw materials in parts by weight: 40% of polyvinylidene fluoride, 10% of polysulfone, 40% of organic solvent, 10% of ethyl orthosilicate, 7% of additive, 4% of amphiphilic copolymer, 6% of nano-particles, 8% of meta-aramid fiber, 10% of pore-forming agent and 8% of glass fiber.
7. A preparation method for a hollow fiber oxygen-enriched membrane is characterized by comprising the following steps:
1) dissolving dried polyvinylidene fluoride, polysulfone, nano particles, meta-aramid fiber, pore-forming agent and glass fiber in an organic solvent, and mixing and stirring until the materials are completely dissolved for later use;
2) putting ethyl orthosilicate into the organic solvent prepared in the step 1), and stirring until the ethyl orthosilicate is completely dissolved for later use;
3) placing the solution in the step 2) at a certain temperature, adding an additive and an amphiphilic copolymer, stirring and defoaming by using a magnetic stirrer, wherein the stirring time is 5-6 h, the defoaming time is 24-48h, and the defoaming temperature is 40-80 ℃ for later use;
4) feeding the mixed solution prepared in the step 3) into a spinning machine, extruding the mixed solution by a spinning nozzle to form hollow fibers, standing until part of solvent in the fibers is evaporated, immersing the fibers into an aqueous solution for solidification, and finally performing surface treatment at the solidification temperature of 5-20 ℃ to form the oxygen-enriched membrane.
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| CN202011550616.8A CN112844071A (en) | 2020-12-24 | 2020-12-24 | Preparation method of hollow fiber oxygen-enriched membrane |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5258227A (en) * | 1987-12-03 | 1993-11-02 | Ppg Industries, Inc. | Chemically treated glass fibers with improved reinforcement properties |
| CN101703895A (en) * | 2009-09-27 | 2010-05-12 | 上海安昆水处理设备有限公司 | Method for preparing high-strength anti-pollution polyvinylidene fluoride ultrafiltration membrane filaments |
| CN104174303A (en) * | 2014-08-26 | 2014-12-03 | 云南云天化股份有限公司 | Enhanced hollow polyvinylidene fluoride fiber ultrafiltration membrane and preparation method thereof |
| CN106178975A (en) * | 2016-08-26 | 2016-12-07 | 广州特锶源净化设备制造有限公司 | A kind of Kynoar/polyacrylonitrile blended hollow-fibre membrane |
| CN108704482A (en) * | 2018-06-28 | 2018-10-26 | 江苏泓膜业科技有限公司 | A kind of antipollution hollow fiber ultrafiltration membrane |
-
2020
- 2020-12-24 CN CN202011550616.8A patent/CN112844071A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5258227A (en) * | 1987-12-03 | 1993-11-02 | Ppg Industries, Inc. | Chemically treated glass fibers with improved reinforcement properties |
| CN101703895A (en) * | 2009-09-27 | 2010-05-12 | 上海安昆水处理设备有限公司 | Method for preparing high-strength anti-pollution polyvinylidene fluoride ultrafiltration membrane filaments |
| CN104174303A (en) * | 2014-08-26 | 2014-12-03 | 云南云天化股份有限公司 | Enhanced hollow polyvinylidene fluoride fiber ultrafiltration membrane and preparation method thereof |
| CN106178975A (en) * | 2016-08-26 | 2016-12-07 | 广州特锶源净化设备制造有限公司 | A kind of Kynoar/polyacrylonitrile blended hollow-fibre membrane |
| CN108704482A (en) * | 2018-06-28 | 2018-10-26 | 江苏泓膜业科技有限公司 | A kind of antipollution hollow fiber ultrafiltration membrane |
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