CN114225708B - A super hydrophilic oleophobic separation membrane for oil-water separation and preparation method thereof - Google Patents
A super hydrophilic oleophobic separation membrane for oil-water separation and preparation method thereof Download PDFInfo
- Publication number
- CN114225708B CN114225708B CN202111491869.7A CN202111491869A CN114225708B CN 114225708 B CN114225708 B CN 114225708B CN 202111491869 A CN202111491869 A CN 202111491869A CN 114225708 B CN114225708 B CN 114225708B
- Authority
- CN
- China
- Prior art keywords
- water
- oil
- super
- phase solution
- hydrophilic oleophobic
- 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.)
- Active
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 96
- 239000012528 membrane Substances 0.000 title claims abstract description 86
- 238000000926 separation method Methods 0.000 title claims abstract description 86
- 238000002360 preparation method Methods 0.000 title claims abstract description 14
- 239000000178 monomer Substances 0.000 claims abstract description 46
- 239000011148 porous material Substances 0.000 claims abstract description 34
- 238000000034 method Methods 0.000 claims abstract description 21
- 150000008065 acid anhydrides Chemical class 0.000 claims abstract description 15
- 150000007519 polyprotic acids Polymers 0.000 claims abstract description 15
- 230000008569 process Effects 0.000 claims abstract description 11
- 239000012071 phase Substances 0.000 claims description 59
- GLUUGHFHXGJENI-UHFFFAOYSA-N Piperazine Chemical compound C1CNCCN1 GLUUGHFHXGJENI-UHFFFAOYSA-N 0.000 claims description 24
- 239000008346 aqueous phase Substances 0.000 claims description 20
- 238000012695 Interfacial polymerization Methods 0.000 claims description 17
- 238000002791 soaking Methods 0.000 claims description 16
- 238000006243 chemical reaction Methods 0.000 claims description 13
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical group CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 claims description 12
- UWCPYKQBIPYOLX-UHFFFAOYSA-N benzene-1,3,5-tricarbonyl chloride Chemical compound ClC(=O)C1=CC(C(Cl)=O)=CC(C(Cl)=O)=C1 UWCPYKQBIPYOLX-UHFFFAOYSA-N 0.000 claims description 9
- WZCQRUWWHSTZEM-UHFFFAOYSA-N 1,3-phenylenediamine Chemical compound NC1=CC=CC(N)=C1 WZCQRUWWHSTZEM-UHFFFAOYSA-N 0.000 claims description 8
- 229940018564 m-phenylenediamine Drugs 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 8
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims description 6
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 6
- LNTHITQWFMADLM-UHFFFAOYSA-N gallic acid Chemical compound OC(=O)C1=CC(O)=C(O)C(O)=C1 LNTHITQWFMADLM-UHFFFAOYSA-N 0.000 claims description 6
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims description 4
- -1 biphenyl anhydride Chemical class 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 239000002904 solvent Substances 0.000 claims description 4
- VLDPXPPHXDGHEW-UHFFFAOYSA-N 1-chloro-2-dichlorophosphoryloxybenzene Chemical compound ClC1=CC=CC=C1OP(Cl)(Cl)=O VLDPXPPHXDGHEW-UHFFFAOYSA-N 0.000 claims description 3
- ZGDMDBHLKNQPSD-UHFFFAOYSA-N 2-amino-5-(4-amino-3-hydroxyphenyl)phenol Chemical compound C1=C(O)C(N)=CC=C1C1=CC=C(N)C(O)=C1 ZGDMDBHLKNQPSD-UHFFFAOYSA-N 0.000 claims description 3
- KCCUBRRTVWFOGF-UHFFFAOYSA-N 2-tritylphenol Chemical group OC1=CC=CC=C1C(C=1C=CC=CC=1)(C=1C=CC=CC=1)C1=CC=CC=C1 KCCUBRRTVWFOGF-UHFFFAOYSA-N 0.000 claims description 3
- LGRFSURHDFAFJT-UHFFFAOYSA-N Phthalic anhydride Natural products C1=CC=C2C(=O)OC(=O)C2=C1 LGRFSURHDFAFJT-UHFFFAOYSA-N 0.000 claims description 3
- 235000010290 biphenyl Nutrition 0.000 claims description 3
- 239000004305 biphenyl Substances 0.000 claims description 3
- JHIWVOJDXOSYLW-UHFFFAOYSA-N butyl 2,2-difluorocyclopropane-1-carboxylate Chemical compound CCCCOC(=O)C1CC1(F)F JHIWVOJDXOSYLW-UHFFFAOYSA-N 0.000 claims description 3
- ZUOUZKKEUPVFJK-UHFFFAOYSA-N phenylbenzene Natural products C1=CC=CC=C1C1=CC=CC=C1 ZUOUZKKEUPVFJK-UHFFFAOYSA-N 0.000 claims description 3
- DKPFZGUDAPQIHT-UHFFFAOYSA-N Butyl acetate Natural products CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 claims description 2
- FUZZWVXGSFPDMH-UHFFFAOYSA-N hexanoic acid Chemical compound CCCCCC(O)=O FUZZWVXGSFPDMH-UHFFFAOYSA-N 0.000 claims description 2
- OCKPCBLVNKHBMX-UHFFFAOYSA-N n-butyl-benzene Natural products CCCCC1=CC=CC=C1 OCKPCBLVNKHBMX-UHFFFAOYSA-N 0.000 claims description 2
- 230000035484 reaction time Effects 0.000 claims description 2
- SRPWOOOHEPICQU-UHFFFAOYSA-N trimellitic anhydride Chemical group OC(=O)C1=CC=C2C(=O)OC(=O)C2=C1 SRPWOOOHEPICQU-UHFFFAOYSA-N 0.000 claims 1
- 230000004907 flux Effects 0.000 abstract description 12
- 239000010865 sewage Substances 0.000 abstract description 11
- 230000000694 effects Effects 0.000 abstract description 5
- 238000006116 polymerization reaction Methods 0.000 abstract description 2
- 235000019198 oils Nutrition 0.000 description 51
- 239000000463 material Substances 0.000 description 21
- 239000002245 particle Substances 0.000 description 20
- 239000004745 nonwoven fabric Substances 0.000 description 17
- 230000004048 modification Effects 0.000 description 12
- 238000012986 modification Methods 0.000 description 12
- 239000004952 Polyamide Substances 0.000 description 10
- 229920002647 polyamide Polymers 0.000 description 10
- 239000012466 permeate Substances 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 7
- 238000009792 diffusion process Methods 0.000 description 6
- 230000002209 hydrophobic effect Effects 0.000 description 6
- 230000003746 surface roughness Effects 0.000 description 6
- 238000012360 testing method Methods 0.000 description 6
- 238000011010 flushing procedure Methods 0.000 description 5
- 229920000728 polyester Polymers 0.000 description 5
- 238000011084 recovery Methods 0.000 description 5
- 238000001612 separation test Methods 0.000 description 5
- 230000036632 reaction speed Effects 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 3
- 238000004132 cross linking Methods 0.000 description 3
- 239000008367 deionised water Substances 0.000 description 3
- 229910021641 deionized water Inorganic materials 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000001728 nano-filtration Methods 0.000 description 3
- 238000000643 oven drying Methods 0.000 description 3
- 230000009257 reactivity Effects 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 239000002033 PVDF binder Substances 0.000 description 2
- 150000001412 amines Chemical class 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 235000019476 oil-water mixture Nutrition 0.000 description 2
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 2
- 238000001223 reverse osmosis Methods 0.000 description 2
- 238000012216 screening Methods 0.000 description 2
- 238000000108 ultra-filtration Methods 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- 239000004695 Polyether sulfone Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 150000001263 acyl chlorides Chemical class 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 238000010612 desalination reaction Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 230000003203 everyday effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005189 flocculation Methods 0.000 description 1
- 230000016615 flocculation Effects 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 229910017053 inorganic salt Inorganic materials 0.000 description 1
- 238000010406 interfacial reaction Methods 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011664 nicotinic acid Substances 0.000 description 1
- 238000000053 physical method Methods 0.000 description 1
- 229920002492 poly(sulfone) Polymers 0.000 description 1
- 229920006393 polyether sulfone Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 230000003075 superhydrophobic effect Effects 0.000 description 1
- 239000002352 surface water Substances 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- NJMOHBDCGXJLNJ-UHFFFAOYSA-N trimellitic anhydride chloride Chemical group ClC(=O)C1=CC=C2C(=O)OC(=O)C2=C1 NJMOHBDCGXJLNJ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
- B01D67/0006—Organic membrane manufacture by chemical reactions
-
- 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
- B01D69/02—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/40—Devices for separating or removing fatty or oily substances or similar floating material
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Analytical Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention provides a super-hydrophilic oleophobic membrane for oil-water separation and a preparation method thereof, wherein a water-soluble monomer with a polyhydroxy structure is added into a water-phase monomer, polybasic acid anhydride is added into an oil-phase monomer, and interface polymerization reaction is carried out on the surface of a porous material and the inside of a pore canal, so that the super-hydrophilic oleophobic membrane with hydrophilicity and high roughness is prepared, the preparation process is simple, and the obtained super-hydrophilic oleophobic membrane has the advantages of high water flux, good hydrophilicity and strong pollution resistance and has good separation effect in the treatment process of oily sewage.
Description
Technical Field
The invention belongs to the technical field of surface modification of separation membranes, and particularly relates to a super-hydrophilic oleophobic separation membrane for oil-water separation and a preparation method thereof.
Background
The source of the oil-water mixture is wide, the ecological environment and the production process are seriously influenced, the environment is protected, the resources are recycled, and the oil-water mixture is required to be separated in safe production. Traditional oil-water separation technology comprises methods of air floatation, flocculation, adsorption, electric dehydration, chemical demulsification and the like. These techniques have the disadvantages of consuming a large amount of energy, adding chemical agents, increasing the amount of sludge, etc. The ultrafiltration membrane separation technology belongs to a physical method, does not need an external medicament, has simple treatment process, can remove the emulsified oil and the dissolved oil which are difficult to treat, and is an ideal oil-water separation technology.
The traditional membrane separation technology mainly adopts aperture screening as a separation mechanism, namely materials with smaller aperture than a separation membrane can permeate the membrane, and materials with larger aperture than the membrane are trapped on the surface of the membrane, so that the separation process is completed. According to the screening principle, if the dissolved oil and the emulsified oil are required to be separated, the pore diameter of the separation membrane is required to be smaller than 0.1 mu m, even smaller than 10nm, and the separation membrane is required to be small in pore diameter, low in porosity and large in filtration resistance, so that the operating pressure is required to be increased. However, the increase of the operating pressure causes oil droplets to deform and permeate the separation membrane, thereby reducing the oil-water separation efficiency of the separation membrane.
In recent years, with the development of bionic technology, scientific researchers have conducted extensive and intensive studies on the superhydrophobic and superhydrophilic phenomena of animals and plants in nature. Wettable surfaces have found widespread use in everyday life and industrial production, such as self-cleaning of building exterior walls, textile surfaces, anti-fog treatment of eyeglass and window surfaces, and the like. From the surface chemistry point of view, a super-wetted surface can be obtained when the surface tension of the solid-liquid is close. The surface tension of the oil substances is 20-40 mN/m, the surface tension of the water is 72mN/m, and the surface tension difference between the oil substances and the water is large, so that a theoretical basis is provided for realizing the oil-water separation process by utilizing the wettability difference of the membrane materials. Most of the current commercial membrane materials are hydrophobic engineering plastics, such as polysulfone, polyethersulfone, polyvinylidene fluoride, polypropylene and the like. The surface energy of the materials is near hydrocarbon materials, and the materials have certain lipophilicity, so that oil drops are easily spread on the surface of the membrane and inside the membrane holes in the oil-water separation process, thereby causing severe fouling of the surface of the membrane, further reducing the flux of the separation membrane, improving the filtration resistance, reducing the service life of the separation membrane and increasing the oil-water separation cost. Therefore, the conventional separation membrane has a large limitation in the oil-water separation process.
The super-infiltration oil-water separation membrane utilizes the difference of the wettability of the membrane materials on oil water instead of the pore diameter of the membrane to separate, and as the surface tension between water and oil is generally very different, one phase can be selectively adsorbed on the surface with different wettability on water and oil, the other phase is repelled, and the wettability of the surface can be enhanced, so that the separation efficiency can be improved. When the oily sewage contacts the surface of the membrane, water can continuously permeate downwards, the surface always keeps super oleophobic, oil is trapped on the surface so as to achieve the effect of oil-water separation, and the potential oleophobic property of the membrane can not pollute the surface of the membrane all the time, so that the membrane is suitable for occasions with more water and less oil, and is a true separation membrane with pollution resistance, low energy consumption, long service life and high efficiency, thereby becoming the main development direction of the oil-water separation membrane in the future.
Compared with the traditional separation membrane, the technology has the following advantages:
the aperture of the separation membrane is large, and the treatment capacity per unit area is large;
The separation membrane has strong anti-pollution capability, can be applied to feed liquid with high viscosity and high concentration, and oil substances are not adhered to the surface of the membrane;
The phase change is not needed in the separation process, the structure of the modification equipment is simple, and the operation cost is low;
the separation membrane can be operated under low pressure (0.1 MPa), and has strong pollution resistance and extremely low operation cost;
In conclusion, the super-hydrophilic oleophobic membrane has the advantages of high water flux and strong anti-pollution capability in the oil-water separation process, can be used for treating high-concentration oily sewage, and greatly reduces the membrane pollution problem in the subsequent ultrafiltration membrane separation process. The super-hydrophilic oleophobic membrane is mostly finished by hydrophilic or hydrophobic modification on the surface of the porous material, and the surface property of the porous material can be modified by a surface modification technology, so that the difference of wettability to oil/water is realized.
The water contact angle of a flat material surface can be expressed by Young's equation:
γsg-γsl＝γlg·cosθ (1)
Wherein: gamma sg、γsl、γlg represents the surface tension of solid-gas, solid-liquid, liquid-gas, respectively, and θ represents the water contact angle. However, the young equation is only suitable for the condition that the surface of the material is flat, and the water contact angle of the rough surface cannot be expressed by the young equation. Water is in two states on the surface of the roughened material: one is that water penetrates into the interstices of the roughened structure, called a Wenzel model; the other is that water does not penetrate between the coarse structures, water drops are suspended on the coarse structures, and one part is contacted with the material and the other part is contacted with air, which is called a Cassie-Baxter model. According to the Wenzel theory:
cosθw＝R·cosθ (2)
wherein: θw represents the Wenzel theoretical water contact angle, θ represents the material planar surface water contact angle, R represents the material surface roughness factor, and R >1. Thus, the higher the surface roughness of the hydrophobic material (the greater R), the greater the water contact angle (θw > θ90°), and the higher the surface roughness of the hydrophilic material, the smaller the water contact angle (θw < θ90°). PVDF material belongs to hydrophobic material, and the surface roughness R is obviously improved so that the theta w is improved. Thus, for hydrophilic materials, the greater the surface roughness, the better the hydrophilicity thereof. Conversely, for hydrophobic materials, the greater the surface roughness, the more hydrophobic it is. Therefore, for the super-hydrophilic oleophobic membrane, increasing the roughness thereof on the basis of maintaining the surface hydrophilicity is a research direction for preparing the super-hydrophilic oleophobic membrane.
The interfacial polymerization method is based on the interfacial polymerization principle proposed by Morgan, and utilizes two reactive monomers with very high reactivity to perform polymerization reaction at an oil-water two-phase interface which is mutually incompatible, so that a compact selective separation skin layer is generated on the surface of a porous supporting layer, and the method is often used for preparing a reverse osmosis or nanofiltration composite membrane. The interfacial reaction can be divided into three phases: (1) In the first stage of the reaction, the aqueous phase amine monomer and the oil phase acyl chloride monomer form a loose initial polyamide film rapidly upon contact, and the film is formed before the reaction reaches the condition of limited diffusion; (2) Since the formed initial polyamide film blocks the diffusion of the aqueous amine monomer into the oil phase reaction zone, the growth of the polyamide film is controlled by limited diffusion; (3) When the resulting polyamide film reaches a certain thickness and density, aqueous monomer diffusion is stopped and interfacial polymerization and film growth are terminated. Because of the self-inhibition property of the interface reaction, the produced polyamide film is uniform and compact and very thin, and only 20-200 nm, so that high flux and desalination rate can be obtained. From the above, it was found that the process of interfacial polymerization of polyamide is affected by both the reaction and diffusion processes. Wherein, the reaction speed of the water phase monomer and the oil phase monomer is the key for controlling the surface morphology of interfacial polymerization. When the interfacial polymerization reaction speed is too high, a stable interfacial layer is formed between two phases, so that the subsequent diffusion process is prevented, and the polyamide layer is smooth. The addition of the additive into the water phase and the oil phase can regulate the reaction speed of the water phase and the oil phase monomer and effectively improve the roughness of the crosslinked layer.
Disclosure of Invention
In view of the above, the invention provides a super-hydrophilic oleophobic membrane for oil-water separation and a preparation method thereof, wherein a water-soluble monomer with a polyhydroxy structure is added into a water phase monomer, a polybasic acid anhydride is added into an oil phase monomer, and interfacial polymerization is carried out on the surface of a porous material and the inside of a pore canal, so that the super-hydrophilic oleophobic membrane with hydrophilicity and high roughness is prepared, the preparation process is simple, the reaction speed is high, and the obtained super-hydrophilic oleophobic membrane has the advantages of high water flux, good hydrophilicity and strong pollution resistance and has good separation effect in the treatment process of oily sewage.
In order to achieve the above purpose, the technical scheme of the invention is realized as follows:
A preparation method of a super-hydrophilic oleophobic separation membrane for oil-water separation comprises the following steps:
s1, preparing an aqueous phase solution: mixing a water-soluble monomer with a polyhydroxy structure with piperazine (PIP) or m-phenylenediamine (MPD) to prepare an aqueous phase solution;
s2, preparing an oil phase solution: mixing polybasic acid anhydride and trimesic acid chloride (TMC) to prepare an oil phase solution;
S3, interfacial polymerization: soaking the porous material in the aqueous phase solution, taking out, drying, soaking in the oil phase solution after drying, and taking out to perform interface reaction;
and S4, repeating the interfacial polymerization process in the step S3 for a plurality of times to obtain the super-hydrophilic oleophobic separation membrane.
Further, in the step S1, the water-soluble monomer with a polyhydroxy structure is triphenylcresol, 3,4, 5-trihydroxybenzoic acid or 3,3' -dihydroxybenzidine.
Further, in the step S1, a water-soluble monomer with a polyhydroxy structure is mixed with piperazine or m-phenylenediamine to obtain a water-phase monomer, wherein the water-soluble monomer with the polyhydroxy structure accounts for 0.5-95 wt% of the total mass of the water-phase monomer; in the aqueous phase solution, the concentration of the aqueous phase monomer obtained by mixing the water-soluble monomer with polyhydroxy structure and piperazine or m-phenylenediamine is 0.01-15 wt%.
In the step S2, the polybasic acid anhydride is trimellitic anhydride chloride, phthalic anhydride, pyromellitic dianhydride or biphenyl anhydride.
Further, in the step S2, polybasic acid anhydride and trimesoyl chloride are mixed to obtain an oil phase monomer, wherein the polybasic acid anhydride accounts for 0.5-95 wt% of the total amount of the oil phase monomer; in the oil phase solution, the concentration of the oil phase monomer obtained by mixing polybasic acid anhydride and trimesoyl chloride is 0.01-15 wt%.
Further, in the aqueous phase solution, the solvent is water; in the oil phase solution, the solvent is n-hexane, ethyl acetate, butyl acetate, benzene or toluene.
Further, in the step S3, the soaking time of the porous material in the aqueous phase solution is 1 min-20 h, and the soaking time of the porous material in the oil phase solution is 1 min-20 h.
Further, in the step S3, the porous material is soaked in the aqueous phase solution, taken out and dried, and the drying temperature is 30 ℃; then soaking the mixture in the oil phase solution, taking out the mixture to perform interface reaction, wherein the temperature for performing the interface reaction is 30-200 ℃, and the reaction time is 1 min-20 h.
In the step S3, the pore size of the porous material is preferably in the range of 0.5 to 50. Mu.m, and the porous material is preferably a porous material such as a nonwoven fabric or a metal screen.
In the step S4, the number of repetition is 2 to 10.
The super-hydrophilic oleophobic separation membrane for oil-water separation is prepared by the preparation method of the super-hydrophilic oleophobic separation membrane for oil-water separation.
The invention applies the interfacial polymerization process to the surface modification process of the porous material, the aperture of the bottom membrane of the original reverse osmosis or nanofiltration membrane is about 10nm, and the polyamide layer can be supported to form a stable separation layer on the surface of the membrane. In the invention, the porous material is used as the bottom membrane, the pore diameter is between 0.5 and 50 mu m, a compact separation layer is not formed under the condition, and the interface crosslinking layer is adhered to the pore canal and the surface of the membrane, so that the wettability of the separation membrane is modified.
The traditional interfacial polymerization adopts piperazine or m-phenylenediamine as a water phase monomer and trimesoyl chloride as an oil phase monomer, and in the process of oil-water interface contact, the water phase monomer and the oil phase monomer quickly form a compact crosslinking layer. Research shows that adding groups with lower reactivity into the water phase and oil phase monomers can delay the separation membrane process and increase the roughness of the crosslinked layer. Meanwhile, part of unreacted groups such as hydroxyl or carboxyl can remain on the surface of the membrane, so that the hydrophilicity of the separation membrane is improved. Researches show that compared with PIP, the hydroxyl reaction activity in the functional monomer with the polyhydroxy structure is low, as the functional monomer with the polyhydroxy structure in the water phase is added, partial hydroxyl and carboxyl remain on the surface of the polyamide, the roughness of the surface of the nanofiltration membrane is increased, the hydrophilicity is improved, the retention rate of inorganic salt is reduced, and the water flux is improved. Similarly, the reactivity of the polybasic acid anhydride is reduced relative to TMC, and as the polybasic acid anhydride is added to the oil phase, part of carboxyl groups remain on the surface of the polyamide layer, the roughness increases, and the hydrophilicity increases.
Compared with the prior art, the super-hydrophilic oleophobic separation membrane for oil-water separation and the preparation method thereof have the following advantages:
(1) According to the preparation method, the water-soluble monomer with the polyhydroxy structure is added into the water-phase monomer, the polybasic acid anhydride is added into the oil-phase monomer, the reaction process of interfacial polymerization is regulated, and the cross-linking layer with the hydrophilic and coarse structures is formed on the surface of the porous material and in the pore canal, so that the super-hydrophilic oleophobic membrane is obtained, the preparation method is simple, the conditions are easy to control, and continuous production can be realized;
(2) The super-hydrophilic oleophobic separation membrane has the advantages of high water flux, high oil-water separation efficiency, good hydrophilicity and strong pollution resistance; the method has wide application range, has good separation effect in the treatment process of oily sewage, can be applied to the fields of sewage treatment, material separation and the like, and has good industrial application value.
Detailed Description
Unless defined otherwise, technical terms used in the following examples have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. 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
4G of triphenylcresol and 6g of PIP were dissolved in 490g of deionized water to prepare an aqueous phase solution, and 0.5g of phthalic anhydride and 0.5gTMC g of n-hexane were dissolved to prepare an oil phase solution. Soaking polyester non-woven fabric (thickness 100 μm, average pore diameter 10 μm) in water phase solution for 10min, taking out, oven drying at 30deg.C for 1 hr, soaking the dried non-woven fabric in oil phase solution for 10min, taking out, and heating in oven at 55deg.C for 20min to complete interfacial polymerization to obtain super hydrophilic oleophobic film.
The water contact angle of the nonwoven fabric before modification was detected to be 75 °, and after modification, the water contact angle of the separation membrane was 15 °, and the nonwoven fabric completely disappeared within 3 seconds.
Oil-water separation test is carried out by adopting oilfield produced water, the oil content in the oilfield produced water before the test is 200ppm, the content of suspended particles is 60ppm, and the median value of particle size is 8 mu m. The water flux of the super-hydrophilic oleophobic membrane in the oily sewage is 500 L.m -2·h-1, and the flow recovery rate of the separation membrane after simple flushing is 94%. The oil content in the permeate is less than 20ppm, the content of suspended particles is 25ppm, and the median particle diameter is less than 5 mu m.
Example 2
2G of 3,4, 5-trihydroxybenzoic acid and 8g of PIP were dissolved in 490g of deionized water to prepare an aqueous phase solution, and 0.2g of pyromellitic dianhydride and 0.8gTMC were dissolved in 199g of n-hexane to prepare an oil phase solution. Soaking polyester non-woven fabric (thickness 100 μm, average pore diameter 10 μm) in water phase solution for 10min, taking out, oven drying at 30deg.C for 1 hr, soaking the dried non-woven fabric in oil phase solution for 15min, taking out, and heating in oven at 55deg.C for 10min to complete interfacial polymerization to obtain super hydrophilic oleophobic film.
The water contact angle of the non-woven fabric before modification is 75 degrees, the water contact angle of the super-hydrophilic oleophobic film after modification is 26 degrees, and the non-woven fabric completely disappears within 5 seconds.
Oil-water separation test is carried out by adopting oilfield produced water, the oil content in the oilfield produced water before the test is 120ppm, the content of suspended particles is 65ppm, and the median value of particle size is 8 mu m. The water flux of the super-hydrophilic oleophobic membrane in the oily sewage is 400 L.m -2·h-1, and the flow recovery rate of the separation membrane after simple flushing is 89%. The oil content in the permeate is less than 12ppm, the content of suspended particles is 25ppm, and the median particle diameter is less than 5 mu m.
Example 3
8G of 3,3' -dihydroxybenzidine and 2g of PIP were dissolved in 490g of deionized water to prepare an aqueous phase solution, and 0.8g of biphenyl anhydride and 0.2gTMC g of n-hexane were dissolved in 199g of n-hexane to prepare an oil phase solution. Soaking polyester non-woven fabric (thickness 200 μm, average pore diameter 8 μm) in water phase solution for 10min, taking out, oven drying at 30deg.C for 1 hr, soaking the dried non-woven fabric in oil phase solution for 20min, taking out, and heating in oven at 55deg.C for 30min to complete interfacial polymerization to obtain super hydrophilic oleophobic film.
The water contact angle of the non-woven fabric before modification is 75 degrees, the water contact angle of the super-hydrophilic oleophobic film after modification is 5 degrees, and the non-woven fabric completely disappears in 1 second.
Oil-water separation test is carried out by adopting oilfield produced water, the oil content in the oilfield produced water before the test is 300ppm, the content of suspended particles is 60ppm, and the median value of particle size is 8 mu m. The water flux of the super-hydrophilic oleophobic membrane in the oily sewage is 400 L.m -2·h-1, and the flow recovery rate of the separation membrane after simple flushing is 93%. The oil content in the permeate is less than 35ppm, the content of suspended particles is 25ppm, and the median particle diameter is less than 5 mu m.
Comparative example 1
The polyester non-woven fabric (thickness 100 μm, average pore diameter 10 μm) is taken, oil-water separation test is carried out by adopting oilfield produced water, the oil content in the oilfield produced water before the test is 120ppm, the suspended particle content is 60ppm, and the median particle diameter is 7 μm.
After the non-woven fabric is filtered, the oil content in the permeate is about 40ppm, the content of suspended particles is 25ppm, and the median particle size is less than 5 mu m. The water flux of the separation membrane in the oily sewage is 80 L.m -2·h-1, and the flow recovery rate of the separation membrane after simple flushing is 35%.
Comparative example 2
The polyester non-woven fabric (thickness 200 μm, average pore diameter 8 μm) is taken, oil-water separation test is carried out by adopting the oilfield produced water, the oil content in the oilfield produced water before the test is 300ppm, the suspended particle content is 60ppm, and the median particle diameter is 6 μm.
After the non-woven fabric is filtered, the oil content in the permeate is about 90ppm, the content of suspended particles is 25ppm, and the median particle size is less than 7 mu m. The water flux of the separation membrane in the oily sewage is 60 L.m -2·h-1, and the flow recovery rate of the separation membrane after simple flushing is 20%.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.
Claims (7)
1. The preparation method of the super-hydrophilic oleophobic separation membrane for oil-water separation is characterized by comprising the following steps of:
S1, preparing an aqueous phase solution: mixing a water-soluble monomer with a polyhydroxy structure with piperazine or m-phenylenediamine to prepare an aqueous phase solution;
s2, preparing an oil phase solution: mixing polybasic acid anhydride and trimesic acid chloride to prepare an oil phase solution;
S3, interfacial polymerization: soaking the porous material in the aqueous phase solution, taking out, drying, soaking in the oil phase solution after drying, and taking out to perform interface reaction;
S4, repeating the interfacial polymerization process in the step S3 for a plurality of times to obtain the super-hydrophilic oleophobic separation membrane;
wherein in the S1, the water-soluble monomer with a polyhydroxy structure is triphenylcresol, 3,4, 5-trihydroxybenzoic acid or 3,3' -dihydroxybenzidine; in the step S2, the polybasic acid anhydride is chlorinated trimellitic anhydride, phthalic anhydride, pyromellitic dianhydride or biphenyl anhydride; in the step S3, the pore diameter of the porous material is in the range of 0.5-50 μm.
2. The method for preparing the super-hydrophilic oleophobic separation membrane for oil-water separation according to claim 1, which is characterized in that: in the S1, a water-soluble monomer with a polyhydroxy structure is mixed with piperazine or m-phenylenediamine to obtain a water-phase monomer, wherein the water-soluble monomer with the polyhydroxy structure accounts for 0.5-95 wt% of the total mass of the water-phase monomer; in the aqueous phase solution, the concentration of the aqueous phase monomer obtained by mixing the water-soluble monomer with polyhydroxy structure and piperazine or m-phenylenediamine is 0.01-15 wt%.
3. The method for preparing the super-hydrophilic oleophobic separation membrane for oil-water separation according to claim 1, which is characterized in that: in the step S2, polybasic acid anhydride and trimesoyl chloride are mixed to obtain an oil phase monomer, wherein the polybasic acid anhydride accounts for 0.5-95 wt% of the total amount of the oil phase monomer; in the oil phase solution, the concentration of the oil phase monomer obtained by mixing polybasic acid anhydride and trimesoyl chloride is 0.01-15 wt%.
4. The method for preparing the super-hydrophilic oleophobic separation membrane for oil-water separation according to claim 1, which is characterized in that: in the aqueous phase solution, the solvent is water; in the oil phase solution, the solvent is n-hexane, ethyl acetate, butyl acetate, benzene or toluene.
5. The method for preparing the super-hydrophilic oleophobic separation membrane for oil-water separation according to claim 1, which is characterized in that: in the step S3, the soaking time of the porous material in the aqueous phase solution is 1 min-20 h, and the soaking time of the porous material in the oil phase solution is 1 min-20 h.
6. The method for preparing the super-hydrophilic oleophobic separation membrane for oil-water separation according to claim 5, which is characterized in that: in the step S3, the porous material is soaked in the aqueous phase solution, taken out and dried, and the drying temperature is 30 ℃; then soaking the mixture in the oil phase solution, taking out the mixture to perform interface reaction, wherein the temperature for performing the interface reaction is 30-200 ℃, and the reaction time is 1 min-20 h.
7. A super hydrophilic oleophobic separation membrane for oil-water separation which characterized in that: which is prepared by the preparation method of the super-hydrophilic oleophobic separation membrane for oil-water separation according to any one of claims 1 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111491869.7A CN114225708B (en) | 2021-12-08 | 2021-12-08 | A super hydrophilic oleophobic separation membrane for oil-water separation and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111491869.7A CN114225708B (en) | 2021-12-08 | 2021-12-08 | A super hydrophilic oleophobic separation membrane for oil-water separation and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114225708A CN114225708A (en) | 2022-03-25 |
| CN114225708B true CN114225708B (en) | 2024-11-15 |
Family
ID=80753977
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111491869.7A Active CN114225708B (en) | 2021-12-08 | 2021-12-08 | A super hydrophilic oleophobic separation membrane for oil-water separation and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114225708B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115672053A (en) * | 2022-11-18 | 2023-02-03 | 天津大学 | Super-hydrophobic fiber membrane with fold structure and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1995001219A1 (en) * | 1993-06-29 | 1995-01-12 | Minnesota Mining And Manufacturing Company | Interfacial polymerization in a porous substrate and substrates functionalized with photochemical groups |
| CN113117530A (en) * | 2020-01-15 | 2021-07-16 | 中国科学院大连化学物理研究所 | Composite membrane for improving permselectivity of polyamide nanofiltration composite membrane and preparation method thereof |
| CN113634133A (en) * | 2021-08-05 | 2021-11-12 | 宁波水艺膜科技发展有限公司 | High-yield semipermeable membrane and preparation method thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111686592A (en) * | 2019-03-11 | 2020-09-22 | 湖州欧美新材料有限公司 | Composite nanofiltration membrane and preparation method thereof |
| CN110433667B (en) * | 2019-09-02 | 2022-03-22 | 天津大学 | Anti-pollution and anti-scaling separation membrane and preparation method thereof |
-
2021
- 2021-12-08 CN CN202111491869.7A patent/CN114225708B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1995001219A1 (en) * | 1993-06-29 | 1995-01-12 | Minnesota Mining And Manufacturing Company | Interfacial polymerization in a porous substrate and substrates functionalized with photochemical groups |
| CN113117530A (en) * | 2020-01-15 | 2021-07-16 | 中国科学院大连化学物理研究所 | Composite membrane for improving permselectivity of polyamide nanofiltration composite membrane and preparation method thereof |
| CN113634133A (en) * | 2021-08-05 | 2021-11-12 | 宁波水艺膜科技发展有限公司 | High-yield semipermeable membrane and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114225708A (en) | 2022-03-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Padaki et al. | Membrane technology enhancement in oil–water separation. A review | |
| Tibi et al. | Fabrication of polymeric membranes for membrane distillation process and application for wastewater treatment: Critical review | |
| US11433358B2 (en) | Composite reverse osmosis membrane and preparation method thereof | |
| Purkait et al. | Introduction to membranes | |
| Kang et al. | Application and modification of poly (vinylidene fluoride)(PVDF) membranes–a review | |
| Baig et al. | Recent progress in microfiltration/ultrafiltration membranes for separation of oil and water emulsions | |
| Ma et al. | Electrospun nanofibrous membranes for desalination | |
| Zuo et al. | A review on thermally stable membranes for water treatment: Material, fabrication, and application | |
| WO2018135999A1 (en) | Hydrophilic polymer and membrane for oil-water separation and method of producing the same | |
| Ismail et al. | Synthetic polymeric membranes for advanced water treatment, gas separation, and energy sustainability | |
| Asatekin et al. | Self-assembled polymer nanostructures for liquid filtration membranes: A review | |
| CN110548420B (en) | Preparation method of zero-flux attenuation chemical heterogeneous hydrogel ultrafiltration membrane | |
| CN114225708B (en) | A super hydrophilic oleophobic separation membrane for oil-water separation and preparation method thereof | |
| Yi et al. | Separation of oil/water emulsion using nano-particle (TiO2/Al2O3) modified PVDF ultrafiltration membranes and evaluation of fouling mechanism | |
| CN113018910A (en) | Preparation method of novel super-hydrophilic oleophobic membrane | |
| CN110280048B (en) | Underwater super-oleophobic and oil-super-hydrophobic material for oil-water emulsion separation and solvent-free preparation method thereof | |
| Modi et al. | Tailor made thin film composite membranes: potentiality towards removal of hydroquinone from water | |
| Ali et al. | Removal of micro-and nanoplastics by filtration technology: performance and obstructions to market penetrations | |
| Hidayah et al. | Improving the performance of polysulfone-nano ZnO membranes for water treatment in oil refinery with modified UV irradiation and polyvinyl alcohol | |
| Liu et al. | Strategies for improving the fouling resistance and stability of super-wettable metal mesh membranes: A review | |
| US11628408B2 (en) | Bilayer electrospun membranes for treating fracking wastewater via membrane distillation | |
| JP5287353B2 (en) | Composite semipermeable membrane | |
| Baig et al. | Composite ceramic membrane containing titanium carbide as an active layer: Fabrication, characterization and its application in oil/water separation | |
| CN113731192B (en) | A hydrophilic ultrafiltration membrane for oil-water separation and a preparation method thereof | |
| Ikhsan et al. | Synthetic polymer-based membranes for treatment of oily wastewater |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |