WO2023035555A1 - 一种正渗透膜及其制备方法 - Google Patents

一种正渗透膜及其制备方法 Download PDF

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WO2023035555A1
WO2023035555A1 PCT/CN2022/078136 CN2022078136W WO2023035555A1 WO 2023035555 A1 WO2023035555 A1 WO 2023035555A1 CN 2022078136 W CN2022078136 W CN 2022078136W WO 2023035555 A1 WO2023035555 A1 WO 2023035555A1
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forward osmosis
osmosis membrane
mesh
nano
support grid
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PCT/CN2022/078136
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English (en)
French (fr)
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唐春
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北京宝盛通国际电气工程技术有限公司
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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
    • B01D69/10—Supported membranes; Membrane supports
    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/10—Supported membranes; Membrane supports
    • B01D69/105—Support pretreatment
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    • B01D67/0002—Organic membrane manufacture
    • B01D67/0009—Organic membrane manufacture by phase separation, sol-gel transition, evaporation or solvent quenching
    • B01D67/0011—Casting solutions therefor
    • B01D67/00113—Pretreatment of the casting solutions, e.g. thermal treatment or ageing
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    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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    • B01D71/06—Organic material
    • B01D71/08—Polysaccharides
    • B01D71/12—Cellulose derivatives
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    • B01D71/06—Organic material
    • B01D71/38—Polyalkenylalcohols; Polyalkenylesters; Polyalkenylethers; Polyalkenylaldehydes; Polyalkenylketones; Polyalkenylacetals; Polyalkenylketals
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    • B01D71/06—Organic material
    • B01D71/40—Polymers of unsaturated acids or derivatives thereof, e.g. salts, amides, imides, nitriles, anhydrides, esters
    • B01D71/42—Polymers of nitriles, e.g. polyacrylonitrile
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    • B01D—SEPARATION
    • B01D2323/00—Details relating to membrane preparation
    • B01D2323/15—Use of additives
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    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B01D2323/15—Use of additives
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    • B01D2323/21813—Metal oxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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    • B01D2325/00—Details relating to properties of membranes
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    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2325/00—Details relating to properties of membranes
    • B01D2325/48—Antimicrobial properties
    • 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
    • B01D61/002—Forward osmosis or direct osmosis
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A20/00—Water conservation; Efficient water supply; Efficient water use
    • Y02A20/124—Water desalination
    • Y02A20/131—Reverse-osmosis

Definitions

  • the invention relates to the technical field of polymer separation membrane preparation, in particular to an antibacterial forward osmosis membrane and a preparation method thereof.
  • the forward osmosis (FO) process is a process in which the osmotic pressure difference between the draw solution and the raw material solution is the driving force, and the water is automatically diffused from the raw water side with low osmotic pressure to the draw solution side with high osmotic pressure through the selective permeable membrane.
  • the process does not require external pressure and energy.
  • forward osmosis can be operated at low pressure or even without pressure, so the energy consumption is low; under low pressure operation, the formation of filter cake layer caused by no pressure has the advantages of Low membrane fouling characteristics.
  • forward osmosis technology As a new type of membrane separation technology, has developed rapidly in recent years, and has also become a hot spot for researchers at home and abroad. It has been applied in food, pharmacy, energy and other fields, and has shown good application prospects in many fields, especially in seawater desalination, drinking water treatment and wastewater treatment.
  • An ideal forward osmosis membrane should have good hydrophilicity, high flux, high salt rejection rate, low internal concentration difference, durability, and good antibacterial properties at the same time. These are also hot research directions in this field in recent years.
  • the two technical solutions all mention that the disclosed technical solutions have antibacterial effects, the two technical solutions all provide a modified forward osmosis membrane by adding graphene material or chitin nanocrystals to the active layer of the forward osmosis membrane.
  • the cellulose triacetate film layer mainly solves performance problems such as increasing water flow and reducing internal concentration polarization, but the antibacterial effect is not strong.
  • forward osmosis membranes can adapt to more complex water quality, but in existing technologies and products, such as the forward osmosis membranes disclosed in the above-mentioned patent applications and patented technologies, because of their antibacterial Insufficient efficiency can not meet the long-term effective use of forward osmosis membrane in complex and nutrient-rich water quality.
  • eutrophic raw water is still easy to cause a large number of bacteria to breed and reproduce on the raw water side, thus fouling the membrane.
  • Membrane performance At present, the urgent need to provide a comprehensive and high-performance forward osmosis membrane has become a key factor in improving the efficiency of forward osmosis.
  • the purpose of the present invention is to propose a forward osmosis membrane capable of inhibiting the growth of bacteria and improving the antibacterial effect so as to improve the performance of the forward osmosis membrane.
  • Another object of the present invention is to propose a method for preparing a forward osmosis membrane capable of inhibiting the growth of bacteria, improving the antibacterial effect, and improving the performance of the forward osmosis membrane.
  • the invention relates to a forward osmosis membrane.
  • the forward osmosis membrane provided by the present invention has a sequentially laminated membrane structure, the laminate includes a hydrophilic support grid and a hydrophilic polymer film layer, and the support grid is modified by antibacterial nanoparticles Non-woven or polyester mesh.
  • the described antibacterial nanoparticles are nano-Ag and nano -TiO mixture, the mass ratio of the two is: 1:1 ⁇ 1:5; the average particle diameter of the described nano-Ag is 20nm; the average particle size of nano TiO 2 is 5-10nm.
  • the nano-Ag and nano -TiO2 mass ratio is: 1:2; more preferably nano-Ag is 0.2wt.%, nano- TiO2 is 0.4wt.%, and the more preferred ratio is to account for the modified suspension Mass specific gravity.
  • the thickness of the support grid is 30 ⁇ m-80 ⁇ m, and the pore size is 100-200 mesh; the thickness of the forward osmosis membrane is 30 ⁇ m-100 ⁇ m; preferably the thickness of the support grid is 30 ⁇ m or 50 ⁇ m or 70 ⁇ m, the pore size is 100 mesh, 120 mesh or 150 mesh; the thickness of the forward osmosis membrane is preferably 30 ⁇ m, 50 ⁇ m or 70 ⁇ m or 100 ⁇ m.
  • the support grid modified by antibacterial nanoparticles is made by the following method: nano-Ag is 0.1-0.5wt.% by mass percentage, nano- TiO2 is by mass percentage 0.2-1wt.%.
  • nano-Ag is 0.1-0.5wt.% by mass percentage
  • nano- TiO2 is by mass percentage 0.2-1wt.%.
  • Into a polyvinyl alcohol aqueous solution with a mass percentage of 2-8wt.% ultrasonically disperse to obtain a modified suspension, impregnate the suspension with a polyester screen, and dry it naturally; preferably, the mass percentage of nano-Ag is 0.2wt. %, nanometer TiO 2 mass percentage 0.4wt.%, polyvinyl alcohol aqueous solution is 4wt.%.
  • the hydrophilic polymer material is polyacrylonitrile, polyacrylate, polymethyl methacrylate, cellulose acetate, cellulose triacetate, polyvinyl alcohol, polyepoxide at least one of ethane and polyvinyl acetate.
  • the present invention also relates to the preparation method that provides forward osmosis membrane, described method comprises:
  • step (c) Pour the casting solution prepared by step (b) on the glass plate covered with the antibacterial modified support grid prepared by step (a), to obtain a nascent forward osmosis membrane of a certain thickness;
  • the antibacterial modified support grid is nano-Ag and nano-TiO 2 Modified polyester mesh is prepared by the following method: adding nano-Ag and nano-TiO 2 into polyvinyl alcohol aqueous solution to prepare a suspension, After the polyester mesh is impregnated with the suspension, it is allowed to dry for later use.
  • the suspension is obtained by the following method: 0.1-0.5wt.% of nano-Ag by mass percentage and 0.2-1wt.% of nano- TiO2 by mass percentage are added to polyvinyl alcohol with a mass percentage of 2-8wt.%.
  • ultrasonic dispersion is obtained; the preferred nano-Ag mass percentage is 0.2wt.%, the nano- TiO2 mass percentage is 1wt.%, and the polyvinyl alcohol mass percentage is 4wt.%.
  • Another preferred nano-Ag mass percentage is 0.2wt.%.
  • nano- TiO2 mass percentage 0.4wt.%
  • the thickness of the support grid is 30 ⁇ m-80 ⁇ m, and the pore diameter is 100-200 mesh; the thickness of the forward osmosis membrane is 30 ⁇ m-100 ⁇ m; preferably, the thickness of the support grid is 30 ⁇ m or 50 ⁇ m or 70 ⁇ m, and the pore diameter is 100 mesh Or 120 mesh or 150 mesh, preferably the thickness of the forward osmosis membrane is 30 ⁇ m, 50 ⁇ m or 70 ⁇ m or 100 ⁇ m.
  • the hydrophilic polymer material is polyacrylonitrile, polyacrylate, polymethyl methacrylate, cellulose acetate, cellulose triacetate, polyvinyl alcohol, polyethylene oxide and polyvinyl acetate at least one of them;
  • the solvent system includes: a mixture of 1,4-dioxane, acetone, methanol and lactic acid;
  • the mass percentage of the hydrophilic polymer is 8-15wt.%, 1,4- The mass percent of dioxane is 30-60wt.%, the mass percent of acetone is 5-20wt.%, the mass percent of methanol is 5-10wt.%, and the mass percent of lactic acid is 6-8wt.%.
  • the step (c) is further as follows: pour the casting solution after step (b-1) defoaming on the glass plate covered with the antibacterial modified hydrophilic support grid, and use a scraping machine to make a certain thickness of the initial ecology Forward osmosis membrane;
  • the obtained nascent forward osmosis membrane is left standing in the air, so that the solvent is volatilized and a dense skin layer is formed on the outer layer;
  • step (e) by immersing the second nascent forward osmosis membrane into deionized water, its gel phase separation is formed into a membrane;
  • step (f) soaking the obtained forward osmosis membrane in step (e) in deionized water to remove residual organic solvent;
  • the hydrophilic support grid is a polyester screen, which is used after pre-cleaning treatment;
  • the pre-cleaning treatment step is: the polyester screen is soaked with 10% sodium hydroxide and 2% hydrochloric acid for 1 Remove the impurities adsorbed on the surface for several hours, then rinse with deionized water, and dry for later use; the thickness of the nascent forward osmosis membrane obtained by using the scraping mechanism is 30 ⁇ m-100 ⁇ m.
  • the mixing condition is to stir at a temperature of 30-50°C for 12-48h to make it evenly mixed, preferably at a temperature of 40°C for 24h;
  • the defoaming method is static Place for 12-36h to fully defoam or assist ultrasonic defoaming, preferably stand for 24 hours for defoaming;
  • the condition for standing in the air is an environment where the temperature is not higher than 25°C and the humidity is not less than 90%, and the standing time is 30-90 seconds to make it form a dense dense skin; preferably under the environment of a temperature of 25 ° C and a humidity of 90% to stand for 60 seconds;
  • the membrane Heat treatment in a water bath at 40-50°C for 5-20 minutes; soaking time in deionized water to remove residual organic solvent is 12-36 hours, preferably soaking 24h; the emphasis in the step (g) of the preparation method The concentration of sodium
  • Antimicrobial nano-particles especially the mixture of nano Ag and nano TiO are fully covered on the supporting grid layer of the membrane, without reducing the strength and water of forward osmosis membrane.
  • antibacterial modification is carried out to the support grid of the forward osmosis membrane by the mixture of antibacterial nanoparticles, especially nano Ag and nano TiO , Inhibit the growth of bacteria on the forward osmosis membrane, improve the forward osmosis, and also improve the safety of the entire purification and filtration system.
  • the antibacterial forward osmosis membrane of the present invention can be applied to the filtration and purification of complex water sources, especially the purification and filtration of eutrophication and bacteria-prone water sources; in addition, the safety of nano-silver has been commercially recognized, and its material has been widely used Used in baby products such as tableware and feeding bottles.
  • Fig. 1 is a schematic flow chart of the preparation process of the forward osmosis membrane of the present invention.
  • FIG. 1 it is a schematic diagram of the process flow for preparing the forward osmosis membrane of the present invention, and the specific description is as follows:
  • the support grid is a hydrophilic non-woven fabric or a polyester mesh.
  • the present invention is further preferred to prepare nano-Ag and nano- TiO2 modified polyester mesh. Add nano-Ag and nano- TiO2 into polyvinyl alcohol aqueous solution, and ultrasonically disperse to obtain a suspension. After the support grid is immersed in the suspension, it is naturally dried for use;
  • casting solution uniformly mix the hydrophilic polymer material and the organic solvent system.
  • the hydrophilic polymer material is further added into the water-soluble organic solvent system mixture, and a uniform casting solution is obtained after stirring at a temperature of 30°C-50°C for 12-48h.
  • step 3 the casting solution obtained in step 2 is left to stand for 12-36h to fully degas or assist ultrasonic degassing; the present invention is further preferably to leave the casting solution for 24h to fully degas;
  • nascent forward osmosis membrane pours the completely defoamed casting solution on a glass plate covered with prepared antibacterial support grid, and use a film scraping mechanism to make a nascent forward osmosis membrane of a certain thickness;
  • the film obtained in step 4 is placed in the air for a few seconds at a certain temperature and humidity to form a dense skin layer, and then immersed in deionized water to form a gel phase separation film; the present invention
  • the temperature is not higher than 25°C, and the humidity is not less than 90% in the air for 30-90 seconds;
  • Optimizing treatment put the membrane obtained in step 5 into a water bath at 40-50°C for heat treatment for 5-20 minutes, and then soak in deionized water for 24 hours to remove residual organic solvents to obtain a further optimized forward osmosis membrane;
  • Preserve for future use take out the forward osmosis membrane and rinse it with deionized water, and store it in a solution of 0.5-2% sodium metabisulfite; preferably 1% sodium metabisulfite solution. Whether to save it for future use as needed.
  • Preparation of casting solution adding 8-15wt.% triacetate cellulose to 5-20wt.% acetone, 5-10wt.% methanol and 6-8wt.% lactic acid , and the rest is 1,4-dioxane, after stirring at a temperature of 40°C for 24 hours, a uniform casting solution is obtained; the obtained casting solution is left to stand for 24 hours to fully defoam or assist ultrasonic defoaming ;
  • the thickness of the modified polyester mesh is 30 ⁇ m - 80 ⁇ m, preferably 30 ⁇ m or 50 ⁇ m or 70 ⁇ m.
  • the antibacterial forward osmosis membrane of the present invention uses 0.5mol/L sodium chloride and 0.01mol/L magnesium sulfate as the drawing liquid and feed liquid respectively, and its membrane flux can reach 8-13L/(m 2 *h), sulfuric acid
  • the interception rate of magnesium is greater than 97%, the antibacterial rate is greater than 90%, and the antibacterial rate is still greater than 90% under the antibacterial durability test.
  • step 6 Put the film obtained in step 5 in an environment with a temperature of 25°C and a humidity of 90%, and let it stand in the air for 30 seconds to form a dense skin layer, and then immerse it in deionized water to make the gel phase-separate into a film;
  • step 7 Put the membrane obtained in step 6 into a water bath at 50°C for heat treatment for 15 minutes, and then soak it in deionized water for 24 hours to remove residual organic solvent;
  • the thickness of the forward osmosis membrane prepared by the above steps is 50 ⁇ m, and 0.5mol/L sodium chloride and 0.01mol/L magnesium sulfate are used as the draw liquid and feed liquid respectively, and the membrane flux can reach 12.5L/(m 2 *h), The rejection rate of magnesium sulfate is 97.8%, and the antibacterial rate is 95%. The anti-bacterial rate is 93% under the anti-bacterial durability test. See Table 1 for specific performance tests.
  • step 6 Put the film obtained in step 5 in an environment with a temperature of 25°C and a humidity of 90%, and let it stand in the air for 60 seconds to form a dense skin layer, and then immerse it in deionized water to separate the gel into a film;
  • step 7 Put the membrane obtained in step 6 into a water bath at 45°C for heat treatment for 20 minutes, and then soak it in deionized water for 24 hours to remove the residual organic solvent;
  • the thickness of the forward osmosis membrane prepared by the above steps is 70 ⁇ m, with 0.5mol/L sodium chloride and 0.01mol/L magnesium sulfate as the draw liquid and feed liquid respectively, the membrane flux can reach 11.0L/(m2*h), sulfuric acid
  • the rejection rate of magnesium is 98.1%, and the antibacterial rate is 94%.
  • the anti-bacterial rate under the anti-bacterial durability test is 92%. See Table 1 for specific performance tests.
  • step 6 Put the film obtained in step 5 in an environment with a temperature of 25°C and a humidity of 90%, and let it stand in the air for 80 seconds to form a dense skin layer, and then immerse it in deionized water to make the gel phase-separate into a film;
  • step 7 Put the membrane obtained in step 6 into a water bath at 40°C for heat treatment for 15 minutes, and then soak it in deionized water for 24 hours to remove residual organic solvent;
  • the thickness of the forward osmosis membrane prepared by the above steps is 100 ⁇ m, and 0.5mol/L sodium chloride and 0.01mol/L magnesium sulfate are used as the draw liquid and feed liquid respectively, and the membrane flux can reach 10.5L/(m 2 *h), The rejection rate of magnesium sulfate is 98.2%, and the antibacterial rate is 95%. The anti-bacterial rate is 93% under the anti-bacterial durability test. See Table 1 for specific performance tests.
  • the forward osmosis membrane of the present invention that has increased the antibacterial support grid has strong antibacterial properties, even after soaking in nutrient-rich raw water for 10 days, and continued testing through simple washing, its antibacterial properties It still remained above 90%, and the flux and salt rejection performance of the membrane were not affected.
  • the forward osmosis membrane formed by the existing cellulose triacetate and the forward osmosis membrane of the existing product do not have antibacterial properties. As the soaking time grows, the membrane performance will seriously decline after biological growth.
  • concentrations of sodium hydroxide, hydrochloric acid and sodium metabisulfite in the examples of the present invention are calculated by mass ratio.
  • the invented forward osmosis membrane is a forward osmosis membrane with an antibacterial modified support grid, which can inhibit the growth of bacteria under the conditions of raw water rich in nutrients, Improve the permeability of the forward osmosis membrane, ensure that the forward osmosis membrane can be used effectively for a long time, prolong the service life of the forward osmosis membrane system and reduce the cost of use.

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Abstract

一种正渗透膜及其制备方法。该正渗透膜具有顺序叠层的膜结构，包括亲水性支撑网格和亲水性聚合物膜层。支撑网格为经过抗菌纳米粒子，特别是纳米Ag和纳米TiO 2的混合物改性的无纺布或聚酯筛网。

Description

一种正渗透膜及其制备方法
相关申请的交叉引用
本申请主张在2021年9月9日在中国提交的中国专利申请号No.202111053419.X的优先权，其全部内容通过引用包含于此。
技术领域
本发明涉及高分子分离膜制备技术领域，具体涉及一种抗菌正渗透膜及其制备方法。
背景技术
正渗透(FO)过程是以汲取液和原料液间的渗透压差为驱动力，使水由低渗透压的原水侧通过选择性透过膜自动扩散至高渗透压的汲取液侧的过程，此过程不需要外加压力和能量。
区别于以压力驱动的膜分离过程如超滤、纳滤和反渗透技术，正渗透可以低压甚至无压操作，因而运行能耗低；低压运行下，无压力导致的滤饼层的形成，具有低的膜污染特征。
在足够的渗透压差的情况下，可以有传统分离膜无法达到的高水回收率。
基于上述正渗透的低能耗、低膜污染、高截留率等优点，正渗透技术作为一种新型的膜分离技术近几年得到了迅速的发展，同时也成为了国内外研究者研究的热点，并已经应用于在食品、药学、能源等领域，在许多领域，特别是在海水淡化、饮用水处理和废水处理中展现出很好的应用前景。
理想的正渗透膜应同时具有良好的亲水性、高通量、高截盐率、低内浓差、耐用、抗菌性好等性能，这些也是近年来本领域研究的热点方向。如现有中国专利申请CN201811285404.4，其揭示了一种无支撑网格的、加入石墨烯的正渗透膜，以达到减少膜的厚度同时通过石墨烯加强膜的强度，提高水通量和减少内浓差极化；以及中国专利CN201410065806.9，其揭示了通过在三醋酸纤维素中混合加入甲壳素纳米晶粒子旨在降低内浓差极化，提高亲水性、减少内浓差极化。虽然该两专利技术都提及所揭示的技术方案有抗菌作用，但是该两技术 方案均通过在正渗透膜的活性层中加入石墨烯材质或甲壳素纳米晶以提供通过改性的正渗透膜的三醋酸纤维素膜层，主要解决的是提高通水量、减少内浓差极化等性能问题，在抗菌方面效果不强。
而近年来，随着对正渗透技术的认识，正渗透膜可以适应更复杂的水质，但现有的技术和产品中，如上述的专利申请及专利技术所揭示的正渗透膜，因其抗菌性效率不足，不能满足正渗透膜在复杂的、富有营养化的水质中长期有效的使用，在长期的使用过程中富营养化的原水仍容易造成大量细菌在原水侧滋生繁殖，从而污堵膜影响膜性能。目前，急需提供一种制备全面高性能的正渗透膜成为了提高正渗透效率的关键因素。
发明内容
本发明的目的是提出一种能够抑制细菌滋生、提高抗菌效果从而提升正渗透膜性能的正渗透膜。
本发明的另一目的是提出一种能够抑制细菌滋生、提高抗菌效果从而提升正渗透膜性能的正渗透膜的制备方法。
为了实现上述目的，本发明采用的技术方案为：
本发明涉及一种正渗透膜。本发明所提供的正渗透膜，其具有顺序叠层的膜结构，该叠层包括亲水性支撑网格和亲水性聚合物膜层，所述支撑网格为经过抗菌纳米粒子改性的无纺布或聚酯筛网。
本发明的另一优选方案为：所述的抗菌纳米粒子为纳米Ag和纳米TiO 2混合物，二者的质量配比为：1:1～1:5；所述的纳米Ag的平均粒径为20nm；纳米TiO 2的平均粒径为5-10nm。优选所述纳米Ag和纳米TiO 2质量比为：1:2；更优选为纳米Ag为0.2wt.％，纳米TiO 2为0.4wt.％，所述的更优选比例为占改性悬浮液的质量比重。
本发明的另一优选方案为：所述支撑网格厚度为30μm-80μm，孔径为100-200目；所述的正渗透膜的厚度为30μm-100μm；优选所述支撑网格厚度为30μm或50μm或70μm，孔径为100目、120目或150目；优选正渗透膜的厚度为30μm、50μm或70μm或100μm。
本发明的另一优选方案为：抗菌纳米粒子改性的支撑网格通过如下方法制得：将纳米Ag按质量百分比0.1-0.5wt.％、纳米TiO 2按质量百分比0.2-1wt.％，加入到质量百分比为2-8wt.％的聚乙烯醇水溶液中，超声分散，制得改性悬浮液，聚酯筛网浸渍该悬浮液后，自然晾干获得；优选为纳米Ag质量百分比0.2wt.％，纳米TiO 2质量百分比0.4wt.％，聚乙烯醇水溶液为4wt.％。
本发明的另一优选方案为：所述的亲水性聚合物材料为聚丙烯腈、聚丙烯酸酯、聚甲基丙烯酸甲酯、醋酸纤维素、三醋酸纤维素、聚乙烯醇、聚环氧乙烷和聚醋酸乙烯酯中的至少一种。
根据本发明的另一目的，本发明还涉及提供正渗透膜的制备方法，所述方法包括：
(a)制备抗菌改性支撑网格，所述支撑网格为亲水性无纺布或聚酯筛网；
(b)制备铸膜液：将亲水性聚合物加入到水溶性溶剂系统中，混合制得铸膜液；
(c)将步骤(b)制备的铸膜液倒在铺有步骤(a)制备的抗菌改性支撑网格的玻璃板上，获得一定厚度的初生态正渗透膜；
(d)对初生态正渗透膜进行外层处理，去除溶剂，在初生态正渗透膜的外层上形成致密皮层，获得第二初生态正渗透膜；
(e)对第二初生态正渗透膜进行分相成膜或界面成膜，获得所述的正渗透膜。
其中，所述抗菌改性支撑网格为纳米Ag和纳米TiO 2改性聚酯筛网，通过如下方法制得：将纳米Ag和纳米TiO 2加入到聚乙烯醇水溶液中，制得悬浮液，聚酯筛网浸渍该悬浮液后，晾干备用。
其中，所述悬浮液通过如下方法获得：将纳米Ag按质量百分比0.1-0.5wt.％、纳米TiO 2按质量百分比0.2-1wt.％，加入到质量百分比为2-8wt.％的聚乙烯醇水溶液中，超声分散获得；优选所述纳米Ag质量百分比0.2wt.％，纳米TiO 2质量百分比1wt.％，聚乙烯醇质量百分比为4wt.％；另优选所述纳米Ag质量百分比0.2wt.％，纳米TiO 2质量百分比0.4wt.％
其中，所述支撑网格厚度为30μm-80μm，孔径为100-200目；所述正渗透膜的厚度为30μm-100μm；优选所述支撑网格厚度为30μm或50μm或70μm，孔径为100目或120目或150目，优选正渗透膜的厚度为30μm、50μm或70μm 或100μm。
其中，所述的亲水性聚合物材料为聚丙烯腈、聚丙烯酸酯、聚甲基丙烯酸甲酯、醋酸纤维素、三醋酸纤维素、聚乙烯醇、聚环氧乙烷和聚醋酸乙烯酯中的至少一种；所述溶剂系统包括：1，4-二氧六环、丙酮、甲醇及乳酸的混合液；所述的亲水聚合物质量百分比为8-15wt.％，1，4-二氧六环质量百分比为30-60wt.％，丙酮质量百分比为5-20wt.％，甲醇质量百分比为5-10wt.％，乳酸质量百分比为6-8wt.％。
其中，还包括如下步骤：
(b-1)将步骤(b)所得到的铸膜液进行脱泡；
所述步骤(c)进一步为：将步骤(b-1)脱泡后的铸膜液倒在铺有抗菌改性亲水性支撑网格的玻璃板，用刮膜机制得一定厚度的初生态正渗透膜；
所述步骤(d)的外层处理及去除溶剂通过将所得到的初生态正渗透膜在空气中静置,使溶剂挥发并在外层形成致密皮层；
所述步骤(e)中通过将第二初生态正渗透膜浸入到去离子水中使其凝胶分相成膜；
(f)将步骤(e)所得到的正渗透膜浸泡在去离子水中去除残留的有机溶剂；
(g)取出正渗透膜用去离子水冲洗后，放于偏重亚硫酸钠的溶液中保存备用。
其中，所述的亲水性支撑网格为聚酯筛网，经过预清洁处理后使用；预清洁处理步骤为：聚酯筛网分别用10％的氢氧化钠、2％的盐酸浸泡处理1小时去除表面吸附的杂质，然后用去离子水冲洗，烘干备用；所述用刮膜机制得初生态正渗透膜厚度为30μm-100μm。
其中，所述制备方法的步骤(b)中，混合条件为在30-50℃的温度下搅拌12-48h，使其混合均匀，优选40℃的温度下搅拌24h；所述脱泡方式为静置12-36h充分脱泡或辅助超声脱泡，优选静置24小时脱泡；所述在空气中静置的条件是温度不高于25℃和湿度不小于90％的环境，静置时间为30-90秒使其形成致密的致密皮层；优选温度25℃和湿度90％的环境下静置60秒；所述制备方法的步骤(f)中，膜在去离子水中浸泡前，先将膜放入40-50℃的水浴中热处理5-20分钟；放入去离子水中去除残留的有机溶剂的浸泡时间为12-36小 时，优选浸泡24h；所述制备方法的步骤(g)中的偏重亚硫酸钠的浓度为0.5-2％之间；优选1％的浓度。
本发明提供的正渗透膜及其制备方法，通过在膜的支撑网格层上全覆盖的设置抗菌纳米粒子，特别是纳米Ag和纳米TiO 2的混合物，在不降低正渗透膜的强度、水通量、截盐率的情况下，提供有效、长期、全面的抗菌效果；本发明中通过抗菌纳米粒子，特别是纳米Ag和纳米TiO 2的混合物对正渗透膜的支撑网格进行抗菌改性，抑制细菌在正渗透膜上的滋生，提升了正渗透性，同时也提升了整个净化、过滤的系统的安全性。本发明抗菌正渗透膜可以应用于复杂的水源的过滤、净化，特别是富营养化、易滋生细菌的水源的净化、过滤；另纳米银安全性已在商业上得到认可，其材质已被广泛应用于婴儿产品中，如餐具和奶瓶中。
附图的简要说明
图1为本发明正渗透膜制备工艺流程示意图。
本发明的实施方式
为更进一步阐述本发明为达成预定目的所采取的技术手段及功效,以下结合附图及较佳实施例，对依据本发明提出的正渗透膜及其制备方法，其具体实施方式、结构、制备方法、特征及其功效，说明如后。本发明提供以下的实施例为进一步描述本发明，但所描述的实施例仅用于说明本发明不是限制本发明。
如图1所示，为本发明正渗透膜制备工艺流程示意图，具体说明如下：
1.制备抗菌性支撑网格：支撑网格为亲水性无纺布或聚酯筛网。本发明进一步优选为制备纳米Ag和纳米TiO 2改性的聚酯筛网。将纳米Ag、纳米TiO 2加入到聚乙烯醇水溶液中，超声分散，制得悬浮液，支撑网格浸渍该悬浮液后，自然晒干备用；
2.制备铸膜液：将亲水性聚合物材料和有机溶剂系统进行均匀混合。本发明进一步为亲水性聚合物材料加入到水溶性有机溶剂系统混合液中，在30℃-50℃的温度下搅拌12-48h之后得到均匀的铸膜液。本发明进一步优选为将三醋酸 纤维素加入到1,4-二氧六环、丙酮、甲醇及乳酸的混合液中，在40℃的温度下搅拌24h之后得到均匀的铸膜液；
3.脱泡：将步骤2所得到的铸膜液静置12-36h充分脱泡或辅助超声脱泡；本发明进一步优选为将铸膜液静置24h充分脱泡；
4.初生态正渗透膜制备：将完全脱泡的铸膜液倒在铺有经过制备的抗菌性支撑网格的玻璃板上，用刮膜机制得一定厚度的初生态正渗透膜；
5.成膜：将步骤4所得到的膜在一定温度和湿度环境下，静置在空气中数秒使其形成致密的皮层，之后浸入到去离子水中使其凝胶分相成膜；本发明中优选为温度不高于25℃，湿度不小于90％的空气中静置30-90秒；
6.优化处理：将步骤5所得到的膜放入40-50℃的水浴中热处理5-20分钟，随后浸泡在去离子水中24h去除残留的有机溶剂，得到进一步优化的正渗透膜；
7.保存备用：取出正渗透膜用去离子水冲洗后，放在0.5-2％偏重亚硫酸钠的溶液中保存备用；优选为1％的偏重亚硫酸钠溶液。根据需要是否进行保存备用。
对本发明提供的正渗透膜的制备方法方案进一步说明如下：
制备纳米Ag/TiO 2改性聚酯筛网：将纳米Ag按质量百分比0.1-0.5wt.％、纳米TiO 2按质量百分比0.2-1wt.％，加入到质量百分比为2-8wt.％的聚乙烯醇水溶液中，通过超声分散，制得悬浮液，聚酯筛网浸渍该悬浮液后，自然晒干备用；
制备铸膜液：将三醋酸纤维素按质量百分比为8-15wt.％加入到丙酮质量百分比为5-20wt.％、甲醇质量百分比为5-10wt.％及乳酸质量百分比为6-8wt.％、其余为1,4-二氧六环的混合液中，在40℃的温度下搅拌24h之后得到均匀的铸膜液；将所得到的铸膜液静置24h充分脱泡或辅助超声脱泡；
将完全脱泡的铸膜液倒在铺有制备好的改性聚酯筛网的玻璃板上，用刮膜机制得30-100μm的初生态正渗透膜；将上一步所得到的膜在温度25℃和湿度90％环境中，静置在空气中60-90秒使其形成致密的皮层，之后浸入到去离子水中使其凝胶分相成膜；改性聚酯筛网的厚度为30μm-80μm，优选30μm或 50μm或70μm。
将凝胶分相成膜所得到的正渗透膜放入40-50℃的水浴中热处理5-15分钟，随后浸泡在去离子水中24h去除残留的有机溶剂。
本发明的抗菌性正渗透膜，以0.5mol/L氯化钠、0.01mol/L硫酸镁分别作为汲取液和料液，其膜通量可以达到8-13L/(m 2*h),硫酸镁的截留率大于97％，抗细菌率大于90％、抗细菌耐久测试下抗细菌率仍大于90％。
下面通过具体的实施例进一步详细说明本发明。
实施例1
1.将厚度为30μm、孔径100目的聚酯筛网分别用2％的盐酸、10％的氢氧化钠浸泡处理1小时去除表面吸附的杂质，然后用去离子水冲洗，烘干备用；
2.制备纳米Ag、纳米TiO 2改性聚酯筛网：将纳米Ag按质量百分比0.2wt.％、纳米TiO 2按质量百分比0.4wt.％，加入到质量百分比4wt.％的聚乙烯醇水溶液中，超声分散，制得悬浮液，聚酯筛网浸渍该悬浮液后，自然晒干备用；
3.将三醋酸纤维素按质量百分比13wt.％加入到1，4-二氧六环质量百分比为54wt.％、丙酮质量百分比为19wt.％、甲醇质量百分比为8wt.％及乳酸质量百分比为6％的混合液中，在40℃的温度下搅拌24h之后得到均匀的铸膜液；
4.将步骤3所得到的铸膜液静置24h充分脱泡或辅助超声脱泡；
5.将完全脱泡的铸膜液倒在铺有制备好的、其厚度为30μm的改性聚酯筛网的玻璃板上，用刮膜机制得厚度50μm初生态正渗透膜；
6.将步骤5所得到的膜在温度25℃和湿度90％环境中，静置在空气中30秒使其形成致密的皮层，之后浸入到去离子水中使其凝胶分相成膜；
7.将步骤6所得到的膜放入50℃的水浴中热处理15分钟，随后浸泡在去离子水中24h去除残留的有机溶剂；
膜性能：
上述步骤制备的正渗透膜厚度为50μm，以0.5mol/L氯化钠、0.01mol/L硫 酸镁分别作为汲取液和料液，其膜通量可以达到12.5L/(m 2*h),硫酸镁的截留率为97.8％，抗菌率为95％。抗细菌耐久测试下抗细菌率为93％。具体性能测试参见表1。
实施例2
1.将厚度为50μm、孔径100目的聚酯筛网分别用2％的盐酸、10％的氢氧化钠浸泡处理1小时去除表面吸附的杂质，然后用去离子水冲洗，烘干备用；
2.制备纳米Ag、纳米TiO 2改性聚酯筛网：将纳米Ag按质量百分比0.2wt.％、纳米TiO 2按质量百分比0.4wt.％，加入到质量百分比为4wt.％的聚乙烯醇水溶液中，通过超声分散，制得悬浮液，聚酯筛网浸渍该悬浮液后，自然晒干备用；
3.将三醋酸纤维素按质量百分比13wt.％加入到1，4-二氧六环质量百分比为54wt.％、丙酮质量百分比为19wt.％、甲醇质量百分比为8wt.％及乳酸质量百分比为6％的混合液中，在40℃的温度下搅拌24h之后得到均匀的铸膜液；
4.将所得到的铸膜液静置24h充分脱泡或辅助超声脱泡；
5.将完全脱泡的铸膜液倒在铺有制备好的、厚度50μm的改性聚酯筛网的玻璃板上，用刮膜机制得厚度70μm初生态正渗透膜；
6.将步骤5所得到的膜在温度25℃和湿度90％环境中，静置在空气中60秒使其形成致密的皮层，之后浸入到去离子水中使其凝胶分相成膜；
7.将步骤6所得到的膜放入45℃的水浴中热处理20分钟，随后浸泡在去离子水中24h去除残留的有机溶剂；
膜性能：
上述步骤制备的正渗透膜厚度为70μm，以0.5mol/L氯化钠、0.01mol/L硫酸镁分别作为汲取液和料液，其膜通量可以达到11.0L/(m2*h)，硫酸镁的截留率为98.1％，抗菌率为94％。抗细菌耐久测试下抗细菌率为92％。具体性能测试参见表1。
实施例3
1.将厚度为50μm、孔径100目的聚酯筛网分别用2％的盐酸、10％的氢氧 化钠浸泡处理1小时去除表面吸附的杂质，然后用去离子水冲洗，烘干备用；
2.制备纳米Ag、纳米TiO 2改性聚酯筛网：将纳米Ag按质量百分比0.2wt.％、纳米TiO 2按质量百分比0.4wt.％加入到质量百分比为4wt.％的聚乙烯醇水溶液中，通过超声分散，制得悬浮液，聚酯筛网浸渍该悬浮液后，自然晒干备用；
3.将三醋酸纤维素按质量百分比10wt.％加入到1,4-二氧六环质量百分比为57wt.％、丙酮质量百分比为19wt.％、甲醇质量百分比为8wt.％及乳酸质量百分比为6％的混合液中，在40℃的温度下搅拌24h之后得到均匀的铸膜液；
4.将所得到的铸膜液静置24h充分脱泡或辅助超声脱泡；
5.将完全脱泡的铸膜液倒在铺有制备好的、厚度50μm的改性聚酯筛网的玻璃板上，用刮膜机制得厚度100μm初生态正渗透膜；
6.将步骤5所得到的膜在温度25℃和湿度90％环境中，静置在空气中80秒使其形成致密的皮层，之后浸入到去离子水中使其凝胶分相成膜；
7.将步骤6所得到的膜放入40℃的水浴中热处理15分钟，随后浸泡在去离子水中24h去除残留的有机溶剂；
膜性能：
上述步骤制备的正渗透膜厚度为100μm，以0.5mol/L氯化钠、0.01mol/L硫酸镁分别作为汲取液和料液，其膜通量可以达到10.5L/(m 2*h),硫酸镁的截留率为98.2％，抗菌率为95％。抗细菌耐久测试下抗细菌率为93％。具体性能测试参见表1。
表1使用0.5mol/L氯化钠、0.01mol/L硫酸镁分别作为汲取液和料液的膜性能评估
Figure PCTCN2022078136-appb-000001
通过表1可以看出，增加了抗菌性支撑网格的本发明正渗透膜具有强的抗菌性，即使在经过10天的富含营养的原水中浸泡后，经过简单冲洗继续测试，其抗菌性仍然保持在90％以上，膜的通量和截盐率性能也没有受到影响。而对于现有的三醋酸纤维素构成的正渗透膜及现有产品的正渗透膜不具有抗菌性，随着浸泡时间长，生物滋生后膜性能下降严重。
本发明实施例中氢氧化钠、盐酸及偏重亚硫酸钠的浓度按质量比算。
本发明提供的正渗透膜及其制备方法中，所发明的正渗透膜是一种带抗菌改性支撑网格的正渗透膜，可以在富含营养的原水环境条件下，抑制细菌的滋生，提高正渗透膜的渗透性，确保正渗透膜可以长期有效的使用，延长正渗透膜系统使用寿命和降低使用成本。
在此说明书中，本发明已参照其特定的实施例作了描述，但是，很显然仍可以做出各种修改和变换而不背离本发明的精神和范围。因此，本发明的说明书和附图被认为是说明性的而非限制性的。

Claims (12)

  1. 一种正渗透膜，其特征在于，其具有顺序叠层的膜结构，该叠层包括亲水性支撑网格和亲水性聚合物膜层，所述支撑网格为经过抗菌纳米粒子改性的无纺布或聚酯筛网，所述支撑网格通过如下方法进行抗菌纳米粒子的改性：将纳米Ag按质量百分比0.1-0.5wt.％、纳米TiO 2按质量百分比0.2-1wt.％，加入到质量百分比为2-8wt.％的聚乙烯醇水溶液中，超声分散制得悬浮液，支撑网格浸渍该悬浮液后，晾干；所述的纳米Ag的平均粒径为20nm，纳米TiO 2的平均粒径为5-10nm；
    所述正渗透膜以0.5mol/L氯化钠、0.01mol/L硫酸镁分别作为汲取液和料液，其膜通量为8-13L/(m 2*h)，硫酸镁的截留率大于97％，抗细菌率大于90％，经过10天的富含营养的原水中浸泡后，经过冲洗继续测试，其抗细菌性仍然保持在90％以上。
  2. 如权利要求1所述的正渗透膜，其特征在于，所述的纳米Ag和纳米TiO 2质量比为：1:2。
  3. 如权利要求2所述的正渗透膜，其特征在于，所述支撑网格厚度为30μm-80μm，孔径为100-200目；所述的正渗透膜的厚度为50μm-100μm。
  4. 如权利要求3所述的正渗透膜，其特征在于，所述支撑网格厚度为30μm或50μm或70μm，孔径为100目或120目或150目；所述正渗透膜的厚度为50μm或70μm或100μm。
  5. 如权利要求1-4中任一项所述的正渗透膜，其特征在于，所述的亲水性聚合物材料为聚丙烯腈、聚丙烯酸酯、聚甲基丙烯酸甲酯、醋酸纤维素、三醋酸纤维素、聚乙烯醇、聚环氧乙烷和聚醋酸乙烯酯中的至少一种。
  6. 一种正渗透膜的制备方法，其特征在于，所述方法包括：
    (a)制备抗菌改性支撑网格，所述支撑网格为亲水性无纺布或聚酯筛网，所述抗菌改性支撑网格为纳米Ag、纳米TiO 2改性支撑网格，通过如下方法制得：将纳米Ag按质量百分比0.1-0.5wt.％、纳米TiO 2按质量百分比0.2-1wt.％，加入到质量百分比为2-8wt.％的聚乙烯醇水溶液中，超声分散制得悬浮液，支撑网格浸渍该悬浮液后，晾干；
    (b)制备铸膜液：将亲水性聚合物加入到水溶性溶剂系统中，混合制得铸膜液；
    (c)将步骤(b)制备的铸膜液倒在铺有步骤(a)制备的抗菌改性支撑网格的玻璃板上，获得一定厚度的初生态正渗透膜；
    (d)对初生态正渗透膜进行外层处理，去除溶剂，在初生态正渗透膜的外层上形成致密皮层，获得第二初生态正渗透膜；
    (e)对第二初生态正渗透膜进行分相成膜或界面成膜，获得所述的正渗透膜；
    所述的纳米Ag的平均粒径为20nm，纳米TiO 2的平均粒径为5-10nm；
    所述正渗透膜以0.5mol/L氯化钠、0.01mol/L硫酸镁分别作为汲取液和料液，其膜通量为8-13L/(m 2*h)，硫酸镁的截留率大于97％，抗细菌率大于90％，经过10天的富含营养的原水中浸泡后，经过冲洗继续测试，其抗细菌性仍然保持在90％以上。
  7. 如权利要求6所述的正渗透膜的制备方法，其特征在于：所述支撑网格厚度为30μm-80μm，孔径为100-200目；所述正渗透膜的厚度为50μm-100μm。
  8. 如权利要求7所述的正渗透膜的制备方法，其特征在于：所述支撑网格厚度为30μm或50μm或70μm，孔径为100目或120目或150目，正渗透膜的厚度为50μm或70μm或100μm。
  9. 如权利要求6-8中任一项所述的正渗透膜的制备方法，其特征在于：所述的亲水性聚合物材料为聚丙烯腈、聚丙烯酸酯、聚甲基丙烯酸甲酯、醋酸纤维素、三醋酸纤维素、聚乙烯醇、聚环氧乙烷和聚醋酸乙烯酯中的至少一种。
  10. 如权利要求6所述的正渗透膜的制备方法，其特征在于，还包括如下步骤：
    (b-1)将步骤(b)所得到的铸膜液进行脱泡；
    所述步骤(c)进一步为：将步骤(b-1)脱泡后的铸膜液倒在铺有亲水性支撑网格的玻璃板上，用刮膜机制得一定厚度的初生态正渗透膜；
    所述步骤(d)的外层处理及去除溶剂通过将所得到的初生态正渗透膜在空气中静置，使溶 剂挥发并在外层形成致密皮层；
    所述步骤(e)中通过将第二初生态正渗透膜浸入到去离子水中使其凝胶分相成膜；
    (f)将步骤(e)所得到的正渗透膜浸泡在去离子水中去除残留的有机溶剂；
    (g)取出正渗透膜用去离子水冲洗后，放于偏重亚硫酸钠的溶液中保存备用。
  11. 如权利要求10所述的正渗透膜的制备方法，其特征在于：所述的亲水性支撑网格为聚酯筛网，其厚度为30μm或50μm或70μm、孔径为100目或120目或150目，经过预清洁处理后使用；预清洁处理步骤为：聚酯筛网分别用10％的氢氧化钠、2％的盐酸浸泡处理1小时去除表面吸附的杂质，然后用去离子水冲洗，烘干备用；所述用刮膜机制得初生态正渗透膜厚度为30μm-100μm。
  12. 如权利要求11所述的正渗透膜的制备方法，其特征在于：所述制备方法的步骤(b)中，混合条件为在30-50℃的温度下搅拌12-48h，使其混合均匀；所述脱泡方式为静置12-36h充分脱泡或辅助超声脱泡；所述在空气中静置的条件是温度不高于25℃和湿度不小于90％的环境，静置时间为30-90秒使其形成致密的致密皮层；所述制备方法的步骤(f)中，膜在去离子水中浸泡前，先将膜放入40-50℃的水浴中热处理5-20分钟，放入去离子水中去除残留的有机溶剂的浸泡时间为12-36小时；所述制备方法的步骤(g)中的偏重亚硫酸钠的浓度为0.5-2％之间。
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Publication number Priority date Publication date Assignee Title
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Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120043274A1 (en) * 2010-04-30 2012-02-23 Woongjin Chemical Co., Ltd. Forward osmosis membrane for seawater desalination and method for preparing the same
WO2012102678A1 (en) * 2011-01-24 2012-08-02 Nano-Mem Pte. Ltd. A forward osmosis membrane
CN103055713A (zh) * 2012-12-28 2013-04-24 中国海洋大学 一种双皮层正渗透膜及其制备方法
CN103816811A (zh) * 2014-02-26 2014-05-28 宁波莲华环保科技股份有限公司 一种有机正渗透膜的制备方法
CN103962015A (zh) * 2014-05-19 2014-08-06 佛山中润水处理科技有限公司 一种复合正渗透膜的制备方法
CN104107638A (zh) * 2013-04-16 2014-10-22 中国科学院宁波材料技术与工程研究所 正渗透膜及其制备方法
CN104258738A (zh) * 2014-09-28 2015-01-07 唐贵凤 正渗透有机-无机复合膜及其制备方法
CN105771680A (zh) * 2016-04-20 2016-07-20 嘉兴中科检测技术服务有限公司 一种复合正渗透膜及其制备方法
CN106917267A (zh) * 2017-04-20 2017-07-04 河南工程学院 一种抗菌高效过滤无纺布的制备方法
CN109012240A (zh) * 2018-07-17 2018-12-18 时代沃顿科技有限公司 一种抗菌耐污染复合反渗透膜及其制备方法
CN111974088A (zh) * 2020-08-12 2020-11-24 广东微量元素生物科技有限公司 一种新型滤材的制作方法
CN113491961A (zh) * 2021-09-09 2021-10-12 北京宝盛通国际电气工程技术有限公司 一种正渗透膜及其制备方法

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8148553B2 (en) * 2009-06-23 2012-04-03 Wisconsin Alumni Research Foundation Catalytic conversion of cellulose to liquid hydrocarbon fuels by progressive removal of oxygen to facilitate separation processes and achieve high selectivities
CN106474944B (zh) * 2016-11-08 2019-04-23 福建农林大学 一种抗菌纤维素平板纳滤膜的制备方法
CN108130745A (zh) * 2017-12-20 2018-06-08 合肥洁诺无纺布制品有限公司 一种抗菌型医用涂布无纺布的制备方法
CN109529623A (zh) 2018-10-31 2019-03-29 中国科学院重庆绿色智能技术研究院 一种无织物的高强度高通量抗菌正渗透膜及其制备方法
CN110523293B (zh) * 2019-09-23 2022-03-04 东华大学 TiO2/AgNPs/PSf复合正渗透膜、制备方法及应用
CN111068519B (zh) * 2019-12-17 2022-04-15 深圳大学 一种正渗透膜及其制备方法

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120043274A1 (en) * 2010-04-30 2012-02-23 Woongjin Chemical Co., Ltd. Forward osmosis membrane for seawater desalination and method for preparing the same
WO2012102678A1 (en) * 2011-01-24 2012-08-02 Nano-Mem Pte. Ltd. A forward osmosis membrane
CN103055713A (zh) * 2012-12-28 2013-04-24 中国海洋大学 一种双皮层正渗透膜及其制备方法
CN104107638A (zh) * 2013-04-16 2014-10-22 中国科学院宁波材料技术与工程研究所 正渗透膜及其制备方法
CN103816811A (zh) * 2014-02-26 2014-05-28 宁波莲华环保科技股份有限公司 一种有机正渗透膜的制备方法
CN103962015A (zh) * 2014-05-19 2014-08-06 佛山中润水处理科技有限公司 一种复合正渗透膜的制备方法
CN104258738A (zh) * 2014-09-28 2015-01-07 唐贵凤 正渗透有机-无机复合膜及其制备方法
CN105771680A (zh) * 2016-04-20 2016-07-20 嘉兴中科检测技术服务有限公司 一种复合正渗透膜及其制备方法
CN106917267A (zh) * 2017-04-20 2017-07-04 河南工程学院 一种抗菌高效过滤无纺布的制备方法
CN109012240A (zh) * 2018-07-17 2018-12-18 时代沃顿科技有限公司 一种抗菌耐污染复合反渗透膜及其制备方法
CN111974088A (zh) * 2020-08-12 2020-11-24 广东微量元素生物科技有限公司 一种新型滤材的制作方法
CN113491961A (zh) * 2021-09-09 2021-10-12 北京宝盛通国际电气工程技术有限公司 一种正渗透膜及其制备方法

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