CN113731192A - Hydrophilic ultrafiltration membrane for oil-water separation and preparation method thereof - Google Patents

Hydrophilic ultrafiltration membrane for oil-water separation and preparation method thereof Download PDF

Info

Publication number
CN113731192A
CN113731192A CN202110983584.9A CN202110983584A CN113731192A CN 113731192 A CN113731192 A CN 113731192A CN 202110983584 A CN202110983584 A CN 202110983584A CN 113731192 A CN113731192 A CN 113731192A
Authority
CN
China
Prior art keywords
membrane
ultrafiltration membrane
oil
water
hydrophilic ultrafiltration
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202110983584.9A
Other languages
Chinese (zh)
Inventor
王新乐
刘铭辉
于海军
付晓燕
王妮
曹兴涛
王国柱
谷广锋
孙扬
薛原
徐洁
王维兵
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dalian Institute of Chemical Physics of CAS
Beijing Security Environmental Engineering Technology Research Institute of CNOOC Energy Technology and Services Ltd
CNOOC Energy Conservation and Environmental Protection Service Co Ltd
Original Assignee
Dalian Institute of Chemical Physics of CAS
Beijing Security Environmental Engineering Technology Research Institute of CNOOC Energy Technology and Services Ltd
CNOOC Energy Conservation and Environmental Protection Service Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dalian Institute of Chemical Physics of CAS, Beijing Security Environmental Engineering Technology Research Institute of CNOOC Energy Technology and Services Ltd, CNOOC Energy Conservation and Environmental Protection Service Co Ltd filed Critical Dalian Institute of Chemical Physics of CAS
Priority to CN202110983584.9A priority Critical patent/CN113731192A/en
Publication of CN113731192A publication Critical patent/CN113731192A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D69/00Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/02Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D61/00Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/14Ultrafiltration; Microfiltration
    • B01D61/145Ultrafiltration
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D67/00Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0002Organic membrane manufacture
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D67/00Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0081After-treatment of organic or inorganic membranes
    • B01D67/0093Chemical modification
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2325/00Details relating to properties of membranes
    • B01D2325/02Details relating to pores or porosity of the membranes
    • B01D2325/022Asymmetric membranes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2325/00Details relating to properties of membranes
    • B01D2325/02Details relating to pores or porosity of the membranes
    • B01D2325/025Finger pores
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2325/00Details relating to properties of membranes
    • B01D2325/24Mechanical properties, e.g. strength
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2325/00Details relating to properties of membranes
    • B01D2325/36Hydrophilic membranes

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Manufacturing & Machinery (AREA)
  • Water Supply & Treatment (AREA)
  • Inorganic Chemistry (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

The invention provides a hydrophilic ultrafiltration membrane for oil-water separation and a preparation method thereof. The preparation method of the hydrophilic ultrafiltration membrane for oil-water separation has the advantages of simple preparation process, mild conditions, convenience for industrial amplification and good industrial application value.

Description

Hydrophilic ultrafiltration membrane for oil-water separation and preparation method thereof
Technical Field
The invention belongs to the technical field of polymer separation membranes, and particularly relates to a hydrophilic ultrafiltration membrane for oil-water separation and a preparation method thereof.
Background
The oil-water mixture has wide sources, has serious influence on ecological environment and production process, and needs to be efficiently separated from the aspects of environmental protection, resource recycling, safe production and the like. The traditional oil-water separation technology comprises methods of air floatation, flocculation, adsorption, electric dehydration, chemical demulsification and the like, and the technologies usually consume a large amount of energy and add chemical agents to generate a large amount of sludge. The ultrafiltration membrane separation technology belongs to a physical method, does not need an additional medicament, has simple treatment process, can remove emulsified oil and dissolved oil which are difficult to treat, and is an ideal oil-water separation technology.
At present, hydrophobic materials such as polysulfone, polyethersulfone and polyvinylidene fluoride are mostly adopted for the organic ultrafiltration membrane, so that the ultrafiltration membrane is hydrophobic. In practical application, the filtration resistance is continuously increased due to the pollution of the membrane, the filtration flux of the membrane is seriously attenuated, and the membrane is frequently cleaned and has high cost. In the oil-water separation process, the membrane pollution phenomenon is particularly obvious. Researches show that hydrophilic modification of the separation membrane is the key for improving the anti-pollution capability of the separation membrane, and the current main hydrophilic modification methods comprise a blending modification technology and a surface modification technology.
The blending modification is a process of adding one or more substances on the basis of the original membrane material and preparing a macroscopically uniform material by mixing. It not only retains the original properties of the original material, but also can overcome the defects of the original material. These modifying materials structurally comprise hydrophilic segments and hydrophobic segments, the hydrophilic segments will automatically concentrate on the membrane surface due to high hydrophilicity during the gel process, and the hydrophobic segments will intertwine with the membrane material and be fixed in the membrane.
The surface modification technology is used for improving the hydrophilicity and the flux of the ultrafiltration membrane through surface reaction and improving the pollution resistance of the membrane. The surface modification method of the membrane mainly comprises the following steps: adsorption method, surface coating method, surface chemical reaction method, low-temperature plasma modification method, ray irradiation modification method, photo-grafting modification method, etc. The adsorption method and the surface coating method are relatively simple to operate, the modifier is physically coated on the surface of the ultrafiltration membrane to be adsorbed on the surface of the ultrafiltration membrane, but the modifier gradually falls off from the surface of the ultrafiltration membrane along with the prolonging of the operation time, and a permanent modification effect cannot be obtained. The surface chemical reaction can fix the modified monomer, the modifier can be grafted to the surface of the ultrafiltration membrane, and the modifier is connected with the polymer through a covalent bond, so that the ultrafiltration membrane has good stability, but the chemical modification process is complex, pretreatment is required, and the modification range is limited; the low-temperature plasma surface modification is a film modification method which is developed rapidly in recent years, is relatively simple to operate and is not easy to pollute air, but modification equipment is relatively complex, the modification mechanism is not clear, and purposeful modification is difficult to carry out; ultraviolet radiation graft polymerization is a common ultrafiltration membrane surface modification method, ultraviolet light is not easy to be absorbed by a polymer membrane, but can be absorbed by a photoinitiator to initiate reaction, so that the purpose of surface modification can be achieved, the material body is not influenced, but the photoinitiator and the catalyst are required to be added, and the grafting rate is not easy to control. The interfacial crosslinking polymerization is a novel ultrafiltration membrane surface modification technology at present, and is characterized in that macromolecules for surface hydrophilic modification are firstly adsorbed on the surface of an ultrafiltration membrane, and then the hydrophilic modification macromolecules are crosslinked by a crosslinking agent to form a network structure so as to improve the stability of the modification macromolecules on the surface of the membrane. The method has the advantages of simple operation, low requirement on equipment, good stability of the hydrophilic modified polymer on the surface of the membrane and wide application range.
The separation layer of the ultrafiltration membrane is thin and is easily damaged by harsh environment, so that the performance of the separation membrane is reduced. Therefore, the ideal separation membrane modification technology has the characteristics of mild reaction conditions, simple equipment and convenience for process amplification. Surface chemical grafting has better stability than other modification techniques, but requires specific chemical sites for surface chemical grafting of separation membranes. The traditional separation membrane material has strong chemical stability, is not easy to carry out chemical grafting reaction, and can generate active sites only by activation. However, the activation process of the separation membrane often causes the breakage of the membrane-forming polymer chain, which affects the membrane pore structure and mechanical properties of the separation membrane. Therefore, if active groups can be introduced into the separation membrane through a blending technology to provide active sites for chemical grafting, and the chemical grafting can be performed under mild reaction conditions to facilitate industrial scale-up, the method is an ideal separation membrane surface modification technology.
Disclosure of Invention
In view of the above, in order to solve the above problems, the invention provides a preparation method of a hydrophilic ultrafiltration membrane for oil-water separation, which has mild reaction conditions, simple process, environmental protection and convenience for industrial amplification, wherein the hydrophilic ultrafiltration membrane has good hydraulic stability, strong pollution resistance, high water flux and good hydrophilicity and can obtain a good separation effect in the process of treating oily sewage by blending polymethyl methacrylate and a film-forming polymer and grafting ethylene glycol onto the surface of the membrane through ester exchange reaction.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
a preparation method of a hydrophilic ultrafiltration membrane for oil-water separation comprises the following steps:
s1, mixing the film-forming polymer with polymethyl methacrylate to prepare a blended film;
and S2, grafting ethylene glycol to the surface of the blend membrane through ester exchange reaction to obtain the target product hydrophilic ultrafiltration membrane.
Further, the S1 specifically includes: dissolving a film-forming polymer, polymethyl methacrylate and an additive in a solvent, uniformly mixing to obtain a film-forming solution, and preparing a blended film by adopting an immersion sedimentation method after vacuum defoaming;
the S2 specifically includes: and soaking the blend membrane in an ethylene glycol solution, and grafting ethylene glycol to the surface of the blend membrane through ester exchange reaction to obtain the hydrophilic ultrafiltration membrane.
Further, the film-forming polymer is polysulfone, polyethersulfone, polyvinylidene fluoride or polyvinyl chloride;
further, the solvent is dimethylacetamide, dimethylformamide, N-methylpyrrolidone or dimethyl sulfoxide.
Further, the additive is a water-soluble additive, a water-insoluble additive, an inorganic salt compound or a combination thereof; the water-soluble additive is one or more of ethylene glycol, propylene glycol, glycerol, triethylene glycol, polyethylene glycol (200, 400 and 600), polyvinylpyrrolidone, polyvinyl butyral and polyvinyl acetate; the water-insoluble additive is one or more of propylene carbonate, gamma-butyrolactone, diacetone alcohol, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monoethyl ether acetate and dipropylene glycol monoethyl ether acetate; the inorganic salt compound is one or more of lithium chloride, lithium nitrate and calcium nitrate.
Further, the sum of the mass of the film forming polymer and the mass of the polymethyl methacrylate accounts for 5-30% of the total mass of the film forming solution, the mass of the additive accounts for 0.5-20% of the total mass of the film forming solution, and the balance is the solvent; wherein the mass ratio of the film-forming polymer to the polymethyl methacrylate is 0.05: 1-20: 1.
Further, in the process of preparing the membrane preparation solution, the reaction temperature is 5-120 ℃, and the time is 1-50 h; in the process of preparing the blend membrane by adopting an immersion sedimentation method, the membrane is replaced by deionized water for 24 hours after being formed.
Further, the glycol solution contains water and a catalyst; the catalyst accounts for 0.0001-5% of the total mass of the glycol solution, and the water accounts for 0.0001-5% of the total mass of the glycol solution.
Further, the catalyst is alkaline inorganic salt, specifically one or more of sodium hydroxide, potassium hydroxide or calcium hydroxide.
Further, the time of the ester exchange reaction is 0.5-50 h, and the temperature of the ester exchange reaction is 5-80 ℃.
A hydrophilic ultrafiltration membrane for oil-water separation is an asymmetric structure of a finger-shaped pore support body.
Further, the hydrophilic ultrafiltration membrane is a flat membrane or a hollow fiber membrane.
Compared with the prior art, the hydrophilic ultrafiltration membrane for oil-water separation and the preparation method thereof have the following advantages:
(1) the preparation method of the hydrophilic ultrafiltration membrane for oil-water separation has mild reaction conditions and simple process, active groups are introduced into the separation membrane through a blending technology, active sites are provided for chemical grafting, the reaction conditions of ester exchange reaction are mild, industrial amplification is facilitated, and the preparation method is an ideal separation membrane surface modification technology and has good industrial application value;
(2) the hydrophilic ultrafiltration membrane for oil-water separation has good hydraulic stability, strong pollution resistance, high water flux and good hydrophilicity, the blending membrane is prepared by mixing the membrane forming polymer and polymethyl methacrylate, and ethylene glycol is grafted to the surface of the blending membrane through ester exchange reaction, so that the hydrophilicity and the pollution resistance of the membrane are improved, and the hydrophilic ultrafiltration membrane has good application value in the fields of oily sewage treatment, material concentration and municipal sewage treatment.
Drawings
FIG. 1 is a photograph showing a cross section of a hollow fiber type hydrophilic ultrafiltration membrane according to an embodiment of the present invention;
FIG. 2 is a cross-sectional photograph of a flat-plate type hydrophilic ultrafiltration membrane according to an embodiment of the present invention
Detailed Description
Unless defined otherwise, technical terms used in the following examples have the same meanings as commonly understood by one of ordinary skill in the art to which the present invention belongs. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods are conventional methods unless otherwise specified.
The present invention will be described in detail with reference to examples.
Example 1
Preparation:
adding 32g of polysulfone, 20g of polymethyl methacrylate and 8g of polyethylene glycol (molecular weight is 400) into 240g of dimethylacetamide, stirring at 70 ℃ for 24 hours to completely dissolve the materials to obtain a membrane preparation solution, defoaming in vacuum, and preparing the hollow fiber membrane by an immersion precipitation method under the following specific spinning conditions:
spinning temperature is 80 ℃, dry spinning distance is 70mm, core liquid is deionized water, and core liquid flow is 0.8 ml/min-1The gel bath is water, the water bath temperature is 50 ℃, and the blending membrane is obtained after deionized water washing.
Adding 5g of deionized water and 5g of sodium hydroxide into 200g of ethylene glycol to obtain an ethylene glycol solution, soaking the blended membrane into the ethylene glycol solution, and reacting at 60 ℃ for 20 hours to obtain the target product, namely the hollow fiber type hydrophilic ultrafiltration membrane.
And (3) performance testing:
the pure water flux of the hollow fiber type hydrophilic ultrafiltration membrane obtained in example 1 was 150 L.m-2·h-1The bovine serum albumin retention rate is 75.5%, and the water contact angle is 34 °.
Oil-water separation test is carried out on the produced water of the oil field, before the test, the oil content in the produced water of the oil field is 120ppm, the suspended particle content is 60ppm, and the median of the particle size is 3 microns.
After filtration with the hollow fiber hydrophilic ultrafiltration membrane prepared in example 1, the oil content in the permeate was less than 10ppm, the suspended particle content was 1ppm, and the median particle size was less than 1 micron. FilmThe water flux in the oily sewage is 30 L.m-2·h-1The flow recovery of the membrane after simple flushing was 85%.
Example 2
Preparation:
adding 36g of polysulfone, 18g of polymethyl methacrylate and 8g of ethylene glycol into 238g of dimethylacetamide, stirring at 80 ℃ for 24 hours to completely dissolve the materials to obtain a membrane preparation solution, defoaming in vacuum, and preparing the hollow fiber membrane by an immersion precipitation method under the following specific spinning conditions:
spinning temperature is 50 ℃, dry spinning distance is 100mm, core liquid is deionized water, and core liquid flow is 1.0 ml/min-1The gel bath is water, the water bath temperature is 50 ℃, and the blending membrane is obtained after deionized water washing.
1g of deionized water and 1g of sodium hydroxide are added into 200g of ethylene glycol to obtain ethylene glycol solution, the blended membrane is soaked into the ethylene glycol solution and reacts for 24 hours at the temperature of 60 ℃, and the target product is the hollow fiber type hydrophilic ultrafiltration membrane.
And (3) performance testing:
the pure water flux of the hollow fiber type hydrophilic ultrafiltration membrane obtained in example 2 was 200 L.m-2·h-1Bovine serum albumin retention was 55.5% and water contact angle was 40 °.
Oil-water separation test is carried out on the produced water of the oil field, before the test, the oil content in the produced water of the oil field is 120ppm, the suspended particle content is 60ppm, and the median of the particle size is 3 microns.
After the hollow fiber type hydrophilic ultrafiltration membrane prepared in example 2 is used for filtration, the oil content in the permeate is less than 16ppm, the content of suspended particles is 2ppm, and the median particle size is less than 1 micron. The water flux of the membrane in the oil-containing wastewater is 30 L.m-2·h-1The flow recovery of the membrane after simple flushing was 75%.
Example 3
Adding 32g of polysulfone, 18g of polymethyl methacrylate and 3g of lithium nitrate into 247g of dimethylformamide, stirring at 80 ℃ for 24 hours to completely dissolve the materials to obtain a membrane-forming solution, defoaming in vacuum, and scraping a flat membrane by an immersion sedimentation method, wherein the specific membrane-scraping conditions are as follows:
the temperature of the film preparation liquid is 50 ℃, the height of a scraper is 200 mu m, the film scraping speed is 0.1 m/s, the temperature of the gel bath is 15 ℃, and the blend film is obtained after deionized water washing.
1g of deionized water and 2g of sodium hydroxide are added into 200g of ethylene glycol to obtain ethylene glycol solution, the blend membrane is soaked into the ethylene glycol solution and reacts for 24 hours at the temperature of 60 ℃, and a target product is a flat plate type hydrophilic ultrafiltration membrane.
And (3) performance testing:
the pure water flux of the flat-plate type hydrophilic ultrafiltration membrane prepared in example 3 was 280L · m-2·h-1Bovine serum albumin retention rate was 35.5% and water contact angle was 48 °.
Oil-water separation test is carried out on the produced water of the oil field, before the test, the oil content in the produced water of the oil field is 100ppm, the suspended particle content is 50ppm, and the median of the particle size is 3 microns.
After filtration with the flat plate hydrophilic ultrafiltration membrane prepared in example 3, the oil content in the permeate was less than 14ppm, the suspended particle content was 2ppm, and the median particle size was less than 1 micron. The water flux of the membrane in the oil-containing wastewater is 35 L.m-2·h-1The recovery rate of the membrane flow after simple flushing was 73%.
Example 4
Preparation:
adding 51g of polyvinylidene fluoride, 18g of polymethyl methacrylate and 9g of propylene glycol into 222g of dimethylformamide, stirring at 70 ℃ for 24 hours to completely dissolve the materials to obtain a membrane preparation solution, defoaming in vacuum, and scraping a flat membrane by an immersion sedimentation method, wherein the specific membrane scraping conditions are as follows:
the temperature of the film-forming liquid is 60 ℃, the height of a scraper is 150 mu m, the film-scraping speed is 0.15m/s, the gel bath is water, the water bath temperature is 15 ℃, and the blended film is obtained after deionized water washing.
1g of deionized water and 2g of sodium hydroxide are added into 200g of ethylene glycol to obtain ethylene glycol solution, the blend membrane is soaked into the ethylene glycol solution and reacts for 24 hours at the temperature of 60 ℃, and a target product is a flat plate type hydrophilic ultrafiltration membrane.
And (3) performance testing:
the pure water flux of the flat-plate hydrophilic ultrafiltration membrane prepared in example 4 was 300 L.m-2·h-1Bovine serum albumin retention was 45.5% and water contact angle was 45 °.
Oil-water separation test is carried out on the produced water of the oil field, the oil content in the produced water of the oil field before the test is 90ppm, the suspended particle content is 50ppm, and the median of the particle size is 2 microns.
After filtration with the flat plate hydrophilic ultrafiltration membrane prepared in example 4, the oil content in the permeate was less than 15ppm, the suspended particle content was 1.5ppm, and the median particle size was less than 1 micron. The water flux of the membrane in the oily sewage is 32 L.m-2·h-1The recovery rate of the membrane flow after simple washing was 70%.
Comparative example 1
Preparation:
32g of polysulfone and 20g of polymethyl methacrylate are added into 248g of dimethylacetamide, stirred for 24 hours at 70 ℃ and completely dissolved to obtain a membrane preparation solution, and after vacuum defoaming, the hollow fiber membrane is prepared by an immersion precipitation method, wherein the specific spinning conditions are as follows:
spinning temperature is 80 ℃, dry spinning distance is 70mm, core liquid is deionized water, and core liquid flow is 0.8 ml/min-1The gel bath is water, the water bath temperature is 50 ℃, and the cellulose hollow fiber membrane is obtained after deionized water washing.
And (3) performance testing:
the spun cellulose hollow fiber membrane is washed in flowing deionized water for 24 hours and then placed in 50 percent glycerol aqueous solution for standby, a scanning electron microscope shows that the membrane is in an asymmetric structure, and the pure water flux of the membrane is 120 L.m-2·h-1The bovine serum albumin retention rate was 42.5% and the water contact angle was 78 °.
Oil-water separation test is carried out on the produced water of the oil field, before the test, the oil content in the produced water of the oil field is 120ppm, the suspended particle content is 60ppm, and the median of the particle size is 3 microns.
After the cellulose hollow fiber membrane filtration, the oil content in the permeated liquid is less than 10ppm, the content of suspended particles is 1ppm, and the median particle size is less than 1 micron. The water flux of the membrane in the oily sewage is 10 L.m-2·h-1The flow recovery of the membrane after simple flushing was 40%.
Comparative example 2
Preparation:
stirring 36g of polyvinylidene fluoride, 12 g of polymethyl methacrylate and 152g of dimethylacetamide at 80 ℃ for 24 hours to completely dissolve the polyvinylidene fluoride, obtaining a membrane preparation solution, defoaming in vacuum, and scraping a flat membrane by an immersion sedimentation method, wherein the specific membrane hanging conditions are as follows:
the temperature of the feed liquid is 60 ℃, the height of the scraper is 200 mu m, the film scraping speed is 0.15m/s, the temperature of the gel bath is 15 ℃, and the blending film is obtained after the deionized water washing.
And (3) performance testing:
the spun flat membrane is washed in flowing deionized water for 24 hours and then placed in 50 percent glycerol aqueous solution for standby, a scanning electron microscope shows that the membrane has an asymmetric structure, and the pure water flux of the membrane is 120 L.m-2·h-1Bovine serum albumin retention rate is 65.5%, and water contact angle is 80 °.
Oil-water separation test is carried out on the produced water of the oil field, before the test, the oil content in the produced water of the oil field is 120ppm, the suspended particle content is 60ppm, and the median of the particle size is 3 microns.
After the flat membrane filtration, the oil content in the permeate is less than 20ppm, the suspended particle content is 1ppm, and the median particle size is less than 1 micron. The water flux of the membrane in the oily sewage is 10 L.m-2·h-1The flow recovery rate of the separation membrane after simple washing was 30%.
As can be seen from the performance test parts of the examples and the comparative examples, the hollow fiber type and flat plate type hydrophilic ultrafiltration membranes described in the examples have strong anti-pollution capability and high water flux, and the flow recovery rate of the membranes after oily sewage treatment and simple flushing is far higher than that of the separation membranes prepared in the comparative examples. The cross-sectional structures of the hollow fiber type and plate type hydrophilic ultrafiltration membranes prepared in examples are shown in fig. 1 and 2.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (10)

1. A preparation method of a hydrophilic ultrafiltration membrane for oil-water separation is characterized by comprising the following steps:
s1, mixing the film-forming polymer with polymethyl methacrylate to prepare a blended film;
and S2, grafting ethylene glycol to the surface of the blend membrane through ester exchange reaction to obtain the target product hydrophilic ultrafiltration membrane.
2. The method for preparing the hydrophilic ultrafiltration membrane for oil-water separation according to claim 1, wherein:
the S1 specifically includes: dissolving a film-forming polymer, polymethyl methacrylate and an additive in a solvent, uniformly mixing to obtain a film-forming solution, and preparing a blended film by adopting an immersion sedimentation method after vacuum defoaming;
the S2 specifically includes: and soaking the blend membrane in an ethylene glycol solution, and grafting ethylene glycol to the surface of the blend membrane through ester exchange reaction to obtain the hydrophilic ultrafiltration membrane.
3. The method for preparing the hydrophilic ultrafiltration membrane for oil-water separation according to claim 2, wherein: the film-forming polymer is polysulfone, polyethersulfone, polyvinylidene fluoride or polyvinyl chloride; the solvent is dimethyl acetamide, dimethyl formamide, N-methyl pyrrolidone or dimethyl sulfoxide.
4. The method for preparing the hydrophilic ultrafiltration membrane for oil-water separation according to claim 2, wherein: the additive is water-soluble additive, water-insoluble additive, inorganic salt compound or their combination; the water-soluble additive is one or more of ethylene glycol, propylene glycol, glycerol, triethylene glycol, polyethylene glycol, polyvinylpyrrolidone, polyvinyl butyral and polyvinyl acetate; the water-insoluble additive is one or more of propylene carbonate, gamma-butyrolactone, diacetone alcohol, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monoethyl ether acetate and dipropylene glycol monoethyl ether acetate; the inorganic salt compound is one or more of lithium chloride, lithium nitrate and calcium nitrate.
5. The method for preparing the hydrophilic ultrafiltration membrane for oil-water separation according to claim 2, wherein: the sum of the mass of the film forming polymer and the polymethyl methacrylate accounts for 5-30% of the total mass of the film forming solution, the mass of the additive accounts for 0.5-20% of the total mass of the film forming solution, and the balance is the solvent; wherein the mass ratio of the film-forming polymer to the polymethyl methacrylate is 0.05: 1-20: 1.
6. The method for preparing the hydrophilic ultrafiltration membrane for oil-water separation according to claim 2, wherein: in the process of preparing the membrane preparation solution, the reaction temperature is 5-120 ℃, and the time is 1-50 h; in the process of preparing the blend membrane by adopting an immersion sedimentation method, the membrane is replaced by deionized water for 24 hours after being formed.
7. The method for preparing the hydrophilic ultrafiltration membrane for oil-water separation according to claim 2, wherein: the glycol solution contains water and a catalyst; the catalyst accounts for 0.0001-5% of the total mass of the glycol solution, and the water accounts for 0.0001-5% of the total mass of the glycol solution.
8. The method for preparing the hydrophilic ultrafiltration membrane for oil-water separation according to claim 7, wherein: the catalyst is one or more of sodium hydroxide, potassium hydroxide or calcium hydroxide.
9. The method for preparing the hydrophilic ultrafiltration membrane for oil-water separation according to claim 2, wherein: the time of the ester exchange reaction is 0.5-50 h, and the temperature of the ester exchange reaction is 5-80 ℃.
10. The hydrophilic ultrafiltration membrane for oil-water separation prepared by the method of any one of claims 1 to 9, wherein: the hydrophilic ultrafiltration membrane is of a finger-shaped pore support asymmetric structure; preferably, the hydrophilic ultrafiltration membrane is a flat membrane or a hollow fiber membrane.
CN202110983584.9A 2021-08-25 2021-08-25 Hydrophilic ultrafiltration membrane for oil-water separation and preparation method thereof Pending CN113731192A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110983584.9A CN113731192A (en) 2021-08-25 2021-08-25 Hydrophilic ultrafiltration membrane for oil-water separation and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110983584.9A CN113731192A (en) 2021-08-25 2021-08-25 Hydrophilic ultrafiltration membrane for oil-water separation and preparation method thereof

Publications (1)

Publication Number Publication Date
CN113731192A true CN113731192A (en) 2021-12-03

Family

ID=78732834

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110983584.9A Pending CN113731192A (en) 2021-08-25 2021-08-25 Hydrophilic ultrafiltration membrane for oil-water separation and preparation method thereof

Country Status (1)

Country Link
CN (1) CN113731192A (en)

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3575946A (en) * 1966-05-24 1971-04-20 Ceskoslovenska Akademie Ved Method of preparing soluble polymers of ethylene glycol
EP0033754A1 (en) * 1980-02-08 1981-08-19 Titmus Eurocon Kontaktlinsen GmbH & Co. KG Process for the hydrophilisation of silicon rubber contact lenses
US4855181A (en) * 1986-12-12 1989-08-08 Kuraray Co., Ltd. Laminate with a blend layer of polyesteramide and ethylene-vinyl acetate copolymer
US5066401A (en) * 1989-07-13 1991-11-19 Akzo N.V. Flat or capillary membrane based on a homogeneous mixture of polyvinylidene fluoride and a second polymer which can be rendered hydrophilic by chemical reaction
WO2007001405A2 (en) * 2004-10-06 2007-01-04 Research Foundation Of Suny High flux and low fouling filtration media
KR20070072120A (en) * 2005-12-30 2007-07-04 주식회사 효성 Method for preparing the chiral filtration membrane
CN101905123A (en) * 2009-06-03 2010-12-08 中国科学院大连化学物理研究所 Blending modification method of polyvinylidene fluoride ultrafiltration membrane
WO2011005258A1 (en) * 2009-07-09 2011-01-13 Board Of Regents, The University Of Texas System Polymer deposition and modification of membranes for fouling resistance
CN102218273A (en) * 2010-04-16 2011-10-19 中国科学院大连化学物理研究所 Preparation method for hydrophilic ultrafiltration membrane
CN102872731A (en) * 2012-10-19 2013-01-16 北京博天环境研究院有限公司 Hollow fiber blend membrane and method for manufacturing same
CN103147224A (en) * 2013-02-22 2013-06-12 哈尔滨工业大学深圳研究生院 Polyvinylidene-fluoride-based composite fibrous membrane, preparation method and application thereof
CN103495348A (en) * 2013-09-30 2014-01-08 广州超禹膜分离技术有限公司 Polyvinyl chloride hollow fiber ultrafiltration membrane and preparation method thereof
CN105879111A (en) * 2014-12-24 2016-08-24 天津科技大学 Novel construction method of biodegradable porous PHBV/PPC (poly (3-hydrobutyrate-3-hydroxyvalerate)/polypropylene carbonate) composite scaffold
CN109111664A (en) * 2018-07-11 2019-01-01 四川羽玺新材料股份有限公司 A kind of PVDF-PET/ graphene quantum dot composite membrane and preparation method thereof
US20190009214A1 (en) * 2017-01-16 2019-01-10 Nanjing University Preparation, regeneration and application of a chelating microfiltration membrane
CN109316981A (en) * 2018-12-10 2019-02-12 天津工业大学 A kind of preparation method of the super hydrophilic polymer film with demulsification function

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3575946A (en) * 1966-05-24 1971-04-20 Ceskoslovenska Akademie Ved Method of preparing soluble polymers of ethylene glycol
EP0033754A1 (en) * 1980-02-08 1981-08-19 Titmus Eurocon Kontaktlinsen GmbH & Co. KG Process for the hydrophilisation of silicon rubber contact lenses
US4855181A (en) * 1986-12-12 1989-08-08 Kuraray Co., Ltd. Laminate with a blend layer of polyesteramide and ethylene-vinyl acetate copolymer
US5066401A (en) * 1989-07-13 1991-11-19 Akzo N.V. Flat or capillary membrane based on a homogeneous mixture of polyvinylidene fluoride and a second polymer which can be rendered hydrophilic by chemical reaction
WO2007001405A2 (en) * 2004-10-06 2007-01-04 Research Foundation Of Suny High flux and low fouling filtration media
KR20070072120A (en) * 2005-12-30 2007-07-04 주식회사 효성 Method for preparing the chiral filtration membrane
CN101905123A (en) * 2009-06-03 2010-12-08 中国科学院大连化学物理研究所 Blending modification method of polyvinylidene fluoride ultrafiltration membrane
WO2011005258A1 (en) * 2009-07-09 2011-01-13 Board Of Regents, The University Of Texas System Polymer deposition and modification of membranes for fouling resistance
CN102218273A (en) * 2010-04-16 2011-10-19 中国科学院大连化学物理研究所 Preparation method for hydrophilic ultrafiltration membrane
CN102872731A (en) * 2012-10-19 2013-01-16 北京博天环境研究院有限公司 Hollow fiber blend membrane and method for manufacturing same
CN103147224A (en) * 2013-02-22 2013-06-12 哈尔滨工业大学深圳研究生院 Polyvinylidene-fluoride-based composite fibrous membrane, preparation method and application thereof
CN103495348A (en) * 2013-09-30 2014-01-08 广州超禹膜分离技术有限公司 Polyvinyl chloride hollow fiber ultrafiltration membrane and preparation method thereof
CN105879111A (en) * 2014-12-24 2016-08-24 天津科技大学 Novel construction method of biodegradable porous PHBV/PPC (poly (3-hydrobutyrate-3-hydroxyvalerate)/polypropylene carbonate) composite scaffold
US20190009214A1 (en) * 2017-01-16 2019-01-10 Nanjing University Preparation, regeneration and application of a chelating microfiltration membrane
CN109111664A (en) * 2018-07-11 2019-01-01 四川羽玺新材料股份有限公司 A kind of PVDF-PET/ graphene quantum dot composite membrane and preparation method thereof
CN109316981A (en) * 2018-12-10 2019-02-12 天津工业大学 A kind of preparation method of the super hydrophilic polymer film with demulsification function

Similar Documents

Publication Publication Date Title
CN103446897B (en) Chemical and ionic cross-linked alginate hydrogel flat membrane for filtration and preparation method thereof
CN103446899B (en) Organic and inorganic surface chemically-crosslinked alginate-based hybrid hydrogel filter membrane, and preparation method thereof
CN106237869B (en) A kind of polyphenol coating hydrophilic method of modified hydrophobic type polymeric membrane
CN103464004B (en) high-strength nano modified ultrafiltration membrane and preparation method thereof
CN109316981A (en) A kind of preparation method of the super hydrophilic polymer film with demulsification function
CN101497002A (en) Method for preparing anti-pollution chitosan-nonwoven cloth composite porous filter membrane
CN110368718B (en) Three-dimensional printed super-hydrophilic and underwater super-oleophobic net film and preparation method thereof
CN106632922B (en) The method of the preparation method and its modified polyvinilidene fluoride microfiltration membranes of block polymer containing hydrophilic segment
CN101327408B (en) Method for preparing antimicrobial modified polyvinyl alcohol-nonwoven compound microporous filtering film
CN113018910A (en) Preparation method of novel super-hydrophilic oleophobic membrane
CN113600037A (en) Renewable PVDF (polyvinylidene fluoride) membrane with adsorption function and preparation method thereof
CN112516817A (en) Polyvinylidene fluoride loose nanofiltration membrane and preparation method and application thereof
CN116036883B (en) Preparation method of fluoropolymer nanofiber-based composite nanofiltration membrane
CN113731192A (en) Hydrophilic ultrafiltration membrane for oil-water separation and preparation method thereof
CN104801209A (en) Ultralow-pressure nanofiltration membrane prepared from imidazole sulfonate grafted polyether sulfone
CN112473400B (en) Graphene micro-ultrafiltration membrane and preparation method thereof
CN116036887A (en) Preparation method of anti-pollution and anti-wetting composite membrane distillation membrane
CN115364680A (en) Alkali-resistant nanofiltration membrane as well as preparation method and application thereof
CN110975637B (en) Preparation method of gallic acid-chitosan/polysulfone composite nanofiltration membrane
CN114618328B (en) Preparation method of PVDF (polyvinylidene fluoride) membrane with emulsion separation and dye adsorption performances
CN114345151B (en) Polymer-based ultrafiltration membrane with high toughness and pollution resistance and preparation method thereof
CN116143227B (en) Method for treating low-concentration heavy metal pollution wastewater by combining adsorption and ultrafiltration
CN115178103B (en) Method for preparing SPVDF porous cation exchange membrane by adopting thermally induced phase separation process and application thereof
CN111001312B (en) Organic-inorganic hybrid membrane and preparation method thereof
CN113265764B (en) Preparation method of heterogeneous nanofiber composite catalytic membrane

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination