CN114669205B - Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane and preparation method thereof - Google Patents
Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane and preparation method thereof Download PDFInfo
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- 239000012528 membrane Substances 0.000 title claims abstract description 196
- 229910003271 Ni-Fe Inorganic materials 0.000 title claims abstract description 72
- 238000001728 nano-filtration Methods 0.000 title claims abstract description 63
- 239000002131 composite material Substances 0.000 title claims abstract description 61
- 229920002492 poly(sulfone) Polymers 0.000 title claims abstract description 48
- 238000002360 preparation method Methods 0.000 title claims abstract description 28
- 239000013078 crystal Substances 0.000 title claims abstract description 26
- 239000013246 bimetallic metal–organic framework Substances 0.000 title claims abstract description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 82
- 238000000034 method Methods 0.000 claims abstract description 46
- 239000001263 FEMA 3042 Substances 0.000 claims abstract description 38
- 229940033123 tannic acid Drugs 0.000 claims abstract description 38
- 229920002258 tannic acid Polymers 0.000 claims abstract description 38
- TUSDEZXZIZRFGC-UHFFFAOYSA-N 1-O-galloyl-3,6-(R)-HHDP-beta-D-glucose Natural products OC1C(O2)COC(=O)C3=CC(O)=C(O)C(O)=C3C3=C(O)C(O)=C(O)C=C3C(=O)OC1C(O)C2OC(=O)C1=CC(O)=C(O)C(O)=C1 TUSDEZXZIZRFGC-UHFFFAOYSA-N 0.000 claims abstract description 36
- LRBQNJMCXXYXIU-PPKXGCFTSA-N Penta-digallate-beta-D-glucose Natural products OC1=C(O)C(O)=CC(C(=O)OC=2C(=C(O)C=C(C=2)C(=O)OC[C@@H]2[C@H]([C@H](OC(=O)C=3C=C(OC(=O)C=4C=C(O)C(O)=C(O)C=4)C(O)=C(O)C=3)[C@@H](OC(=O)C=3C=C(OC(=O)C=4C=C(O)C(O)=C(O)C=4)C(O)=C(O)C=3)[C@H](OC(=O)C=3C=C(OC(=O)C=4C=C(O)C(O)=C(O)C=4)C(O)=C(O)C=3)O2)OC(=O)C=2C=C(OC(=O)C=3C=C(O)C(O)=C(O)C=3)C(O)=C(O)C=2)O)=C1 LRBQNJMCXXYXIU-PPKXGCFTSA-N 0.000 claims abstract description 36
- LRBQNJMCXXYXIU-NRMVVENXSA-N tannic acid Chemical compound OC1=C(O)C(O)=CC(C(=O)OC=2C(=C(O)C=C(C=2)C(=O)OC[C@@H]2[C@H]([C@H](OC(=O)C=3C=C(OC(=O)C=4C=C(O)C(O)=C(O)C=4)C(O)=C(O)C=3)[C@@H](OC(=O)C=3C=C(OC(=O)C=4C=C(O)C(O)=C(O)C=4)C(O)=C(O)C=3)[C@@H](OC(=O)C=3C=C(OC(=O)C=4C=C(O)C(O)=C(O)C=4)C(O)=C(O)C=3)O2)OC(=O)C=2C=C(OC(=O)C=3C=C(O)C(O)=C(O)C=3)C(O)=C(O)C=2)O)=C1 LRBQNJMCXXYXIU-NRMVVENXSA-N 0.000 claims abstract description 36
- 235000015523 tannic acid Nutrition 0.000 claims abstract description 36
- 239000012917 MOF crystal Substances 0.000 claims abstract description 21
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- 230000008569 process Effects 0.000 claims abstract description 14
- 239000000243 solution Substances 0.000 claims description 66
- 238000000108 ultra-filtration Methods 0.000 claims description 41
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 40
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- 229910021641 deionized water Inorganic materials 0.000 claims description 32
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- 239000001509 sodium citrate Substances 0.000 claims description 5
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- 238000009210 therapy by ultrasound Methods 0.000 claims description 5
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- 229910021578 Iron(III) chloride Inorganic materials 0.000 claims description 4
- 238000011010 flushing procedure Methods 0.000 claims description 4
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 4
- 238000004321 preservation Methods 0.000 claims description 4
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- IQFVPQOLBLOTPF-HKXUKFGYSA-L congo red Chemical compound [Na+].[Na+].C1=CC=CC2=C(N)C(/N=N/C3=CC=C(C=C3)C3=CC=C(C=C3)/N=N/C3=C(C4=CC=CC=C4C(=C3)S([O-])(=O)=O)N)=CC(S([O-])(=O)=O)=C21 IQFVPQOLBLOTPF-HKXUKFGYSA-L 0.000 description 6
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- STZCRXQWRGQSJD-GEEYTBSJSA-M methyl orange Chemical compound [Na+].C1=CC(N(C)C)=CC=C1\N=N\C1=CC=C(S([O-])(=O)=O)C=C1 STZCRXQWRGQSJD-GEEYTBSJSA-M 0.000 description 5
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- RGCKGOZRHPZPFP-UHFFFAOYSA-N alizarin Chemical compound C1=CC=C2C(=O)C3=C(O)C(O)=CC=C3C(=O)C2=C1 RGCKGOZRHPZPFP-UHFFFAOYSA-N 0.000 description 4
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- 125000004122 cyclic group Chemical group 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- MCPLVIGCWWTHFH-UHFFFAOYSA-L methyl blue Chemical compound [Na+].[Na+].C1=CC(S(=O)(=O)[O-])=CC=C1NC1=CC=C(C(=C2C=CC(C=C2)=[NH+]C=2C=CC(=CC=2)S([O-])(=O)=O)C=2C=CC(NC=3C=CC(=CC=3)S([O-])(=O)=O)=CC=2)C=C1 MCPLVIGCWWTHFH-UHFFFAOYSA-L 0.000 description 4
- PYWVYCXTNDRMGF-UHFFFAOYSA-N rhodamine B Chemical compound [Cl-].C=12C=CC(=[N+](CC)CC)C=C2OC2=CC(N(CC)CC)=CC=C2C=1C1=CC=CC=C1C(O)=O PYWVYCXTNDRMGF-UHFFFAOYSA-N 0.000 description 4
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- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
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- JXDYKVIHCLTXOP-UHFFFAOYSA-N isatin Chemical compound C1=CC=C2C(=O)C(=O)NC2=C1 JXDYKVIHCLTXOP-UHFFFAOYSA-N 0.000 description 2
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- 239000013154 zeolitic imidazolate framework-8 Substances 0.000 description 2
- MFLKDEMTKSVIBK-UHFFFAOYSA-N zinc;2-methylimidazol-3-ide Chemical compound [Zn+2].CC1=NC=C[N-]1.CC1=NC=C[N-]1 MFLKDEMTKSVIBK-UHFFFAOYSA-N 0.000 description 2
- CTENFNNZBMHDDG-UHFFFAOYSA-N Dopamine hydrochloride Chemical compound Cl.NCCC1=CC=C(O)C(O)=C1 CTENFNNZBMHDDG-UHFFFAOYSA-N 0.000 description 1
- 229910017135 Fe—O Inorganic materials 0.000 description 1
- WTDRDQBEARUVNC-LURJTMIESA-N L-DOPA Chemical compound OC(=O)[C@@H](N)CC1=CC=C(O)C(O)=C1 WTDRDQBEARUVNC-LURJTMIESA-N 0.000 description 1
- WTDRDQBEARUVNC-UHFFFAOYSA-N L-Dopa Natural products OC(=O)C(N)CC1=CC=C(O)C(O)=C1 WTDRDQBEARUVNC-UHFFFAOYSA-N 0.000 description 1
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- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- YCIMNLLNPGFGHC-UHFFFAOYSA-N catechol Chemical group OC1=CC=CC=C1O YCIMNLLNPGFGHC-UHFFFAOYSA-N 0.000 description 1
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- 238000004043 dyeing Methods 0.000 description 1
- 238000002848 electrochemical method Methods 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000005189 flocculation Methods 0.000 description 1
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- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/66—Polymers having sulfur in the main chain, with or without nitrogen, oxygen or carbon only
- B01D71/68—Polysulfones; Polyethersulfones
-
- 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
- B01D67/0081—After-treatment of organic or inorganic membranes
- B01D67/0093—Chemical modification
-
- 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
- B01D69/12—Composite membranes; Ultra-thin membranes
- B01D69/125—In situ manufacturing by polymerisation, polycondensation, cross-linking or chemical reaction
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/02—Inorganic material
- B01D71/022—Metals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/76—Macromolecular material not specifically provided for in a single one of groups B01D71/08 - B01D71/74
- B01D71/82—Macromolecular material not specifically provided for in a single one of groups B01D71/08 - B01D71/74 characterised by the presence of specified groups, e.g. introduced by chemical after-treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/36—Introduction of specific chemical groups
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/40—Details relating to membrane preparation in-situ membrane formation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/02—Details relating to pores or porosity of the membranes
- B01D2325/022—Asymmetric membranes
- B01D2325/023—Dense layer within the membrane
-
- 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
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The application belongs to the field of new materials and environmental protection treatment, and particularly relates to a Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane and a preparation method thereof, wherein the nanofiltration membrane adopts tannic acid and Fe 3+ The PSF substrate film is modified to obtain a functional modified film; and then placing the modified film in a mother solution of Ni-Fe MOF, and adopting a growth method of growing layer by layer and then growing in situ, thereby effectively solving the problem of cracking of the crystal layer caused by the rigidity of the Ni-Fe MOF and obtaining a continuous and compact Ni-Fe MOF crystal layer on the surface of the film. The prepared modified polysulfone nanofiltration membrane has the trapping rate of more than 99 percent for dye molecules with the molecular weight of 342-800Da and the water flux of 61.5+/-5.5 L.m ‑2 ·h ‑1 ·bar ‑1 And the whole process does not need to use an organic solvent, is simple to operate, does not need high-temperature and high-pressure conditions, and accords with a safe production process.
Description
Technical Field
The application belongs to the field of new materials and environmental protection treatment, and particularly relates to a Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane and a preparation method thereof.
Background
The global current state of water resources in recent years is not optimistic. On one hand, the attenuation rate of water resources in many places reaches 10-20% due to the influence of climate change and artificial activities; on the other hand, the industrial and domestic water consumption reaches 2000 hundred million tons per year, and the wastewater discharge reaches the scale of 700 hundred million tons. Wherein the printing and dyeing wastewater accounts for 10% of the total industrial wastewater discharge amount; in recent years, the color requirements are higher and higher, the types of dyes are increased, and the colors are developed towards photolysis resistance, oxidation resistance and biodegradation resistance, so that the dye wastewater is difficult to treat in a general water purification mode.
The existing water treatment technology includes chemical treatment, biological method, physicochemical method and the like. The chemical treatment method comprises a chemical flocculation method, a chemical oxidation method and an electrochemical method, the method has obvious decoloring effect on macromolecular water-soluble dye which is easy to form colloid and dye with strong oxidability, the pigment removal rate is about 85 percent, but the problems of obvious increase of running cost and increase of recycling difficulty are faced with the increase of the decoloring rate; the biological method comprises an aerobic treatment method, an anaerobic treatment method and an anaerobic-aerobic combined treatment method, and the method has good removal rate of 99 percent for biodegradable dye and refractory organic matters, but also has a series of problems of higher cost, low removal rate of colorimetric reagents, difficult achievement of emission standards and the like; the physicochemical method comprises an adsorption method, an extraction method and a membrane separation method, and the adsorption method and the extraction method have important application in water treatment, but have the problems of difficult regeneration of the adsorbent and higher cost.
Compared with the prior art, the membrane separation technology belongs to a new and gradually rising separation technology, has the advantages of low energy consumption, simple operation, small occupied area, no secondary pollution, stable quality of produced water and the like, is called a third generation drinking water treatment technology, and is widely applied to wastewater treatment, sea water desalination, pharmacy and food engineering. Therefore, the development of the low-cost nanofiltration membrane with good separation effect, high water flux and strong pollution resistance is important.
At present, the mode for preparing the nanofiltration membrane comprises three main modes of interfacial polymerization, blending and grafting modification. The interfacial polymerization method is to polymerize reactants at mutually-insoluble two-phase interfaces to form a film, and the double-layer nanofiltration membrane prepared by the interfacial polymerization method has excellent interception effect, but is difficult to overcome the problems of low water flux and high energy consumption; the blending method is to blend small-particle porous substances with membrane materials in a liquid phase, and form a membrane by a phase inversion mode, so that the nanofiltration membrane prepared by the blending method needs to overcome the problem of compatibility; the graft copolymerization comprises ultraviolet light grafting, electron beam irradiation, in-situ growth, layer-by-layer growth and other methods, wherein the method of the graft copolymerization can fix the porous material on the surface of the membrane, and compared with other methods, the graft copolymerization can expose the pore canal of MOFs crystal to the greatest extent and coordinate the trade-off effect between the interception rate of the nanofiltration membrane and the water flux to the greatest extent. Xu et al used surface graft copolymerization to prepare Tannic Acid (TA) and Fe 3+ Crosslinking and complexing Polyethylenimine (PEI) to form net-shaped TA-Fe 3+ Compared with MOFs functional layer composite membranes, the composite membranes prepared by the method are easy to have surface nodules, so that the problem of uneven pore channel distribution is caused. The ZIF-8 crystal layer membrane prepared by Zhang et al has relatively uniform pore channels exposed on the surface of the membrane, and the nanofiltration performance of the membrane becomes extremely stable after DNA is introduced to solve the problem of poor water stability of ZIF-8.
Therefore, how to provide a more convenient method for preparing nanofiltration membrane with excellent nanofiltration performance by combining with the prior art is a problem to be solved in the field.
Disclosure of Invention
Aiming at a plurality of defects existing in the prior art, the application provides a Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane and a preparation method thereof, wherein the nanofiltration membrane adopts tannic acid and Fe 3+ The PSF substrate film is modified to obtain a functional modified film; then placing the modified film in a mother solution of Ni-Fe MOF, and adopting a growth method of growing layer by layer and then growing in situ, thereby effectively solving the problem of crystal layer cracking caused by the rigidity of the Ni-Fe MOF and obtaining a continuous and compact Ni-Fe MOF crystal layer on the surface of the film; the prepared modified polysulfone nanofiltration membrane is prepared byThe retention rate of dye molecules with molecular weight of 342-800Da can reach more than 99%, and the water flux is 61.5+/-5.5 L.m -2 ·h -1 ·bar -1 And the whole process does not need to use an organic solvent, is simple to operate, does not need high-temperature and high-pressure conditions, and accords with a safe production process.
The specific inventive concept of the present application is as follows:
according to the application, metal organic frame Materials (MOFs) are modified to the surface of the PSF ultrafiltration membrane through coordination, so that the target nanofiltration membrane is prepared, and the MOFs and the organic ultrafiltration membrane materials have good compatibility by means of coordination synergism between metal and functional groups, so that the problem of poor compatibility of the nanofiltration membrane prepared by a blending method is solved, and MOFs crystal layers with buffer layers are prepared in a mode of combining layer-by-layer growth and in-situ construction, so that not only can the influence of crystal layer cracking caused by expansion of organic and inorganic layers be reduced, but also the problem of low flux caused by over-compactness of membrane materials prepared by an interfacial polymerization method can be solved.
In a specific development process, the inventor also successively discovers that the introduction of Ni-Fe MOF into the polysulfone substrate membrane is greatly helpful for improving the nanofiltration performance of the composite membrane. The maximum aperture of the Ni-Fe MOF is less than 0.51nm, dye molecules with the molecular weight of 342-800Da can be filtered, and a periodic porous topological structure can construct rich water channels, so that high retention rate and high water flux can be ensured theoretically.
Because the PSF base film surface lacks the growth sites of Ni-Fe MOF, the inventor finally decides to select TA and Fe 3+ The TA can be firmly adhered to the surface of the PSF base film on one hand and the phenolic hydroxyl group rich in the TA can be combined with Fe on the other hand by carrying out interlayer modification 3+ Coordination reaction and uniformly coordinated Fe 3+ Ligands of the MOF can be anchored, providing a growth site for the MOF.
In the preparation process, the Ni-Fe MOF has strong rigidity and can break when growing on a flexible substrate, and the inventor selects the MOF rich in-NH 2 Polyethylene imine (PEI), which can be mixed with Ni 2+ Form coordination bonding, and grow the thin MOFs/PEI buffer layer of preparation layer by layer, the introduction of the buffer layer can effectively alleviate the cracking problem of Ni-Fe MOF crystal layer. Existing technologyAlthough there is a precedent in the art of modification with polyethyleneimine, the method is more effective than the method of modification by Fe 3+ The crosslinking polyethylene imine-tannic acid composite nanofiltration membrane is researched, and the action mechanism of the crosslinking polyethylene imine-tannic acid composite nanofiltration membrane is that micropores of a polysulfone membrane are covered by a network structure of PEI-TA so that the micropores are changed into smaller nanopores; the conception of the application is to use the pore canal of the Ni-Fe PBA crystal to block the micropores of the polysulfone membrane and change the micropores into smaller nanopores; and TA-Fe 3+ The concept of acting mainly as an intermediate layer is quite different from the one used for the first time in the art.
Based on the above, the application performs TA-Fe on PSF ultrafiltration membrane 3+ Introducing PEI to grow a Ni-Fe MOF/PEI buffer layer by a layer-by-layer growth mode, and finally constructing a Ni-Fe MOF crystal separation layer by an in-situ growth mode. The Ni-Fe MOF crystal layer/polysulfone composite nanofiltration membrane is tested and characterized.
Under the guidance of the inventive concept, the specific technical scheme of the application is as follows:
a Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane adopts tannic acid and Fe 3+ The PSF substrate film is modified to obtain a functional modified film; then placing the modified membrane in a mother solution of Ni-Fe MOF, and adopting a growth method of growing layer by layer and then growing in situ to obtain a continuous compact Ni-Fe MOF crystal layer on the surface of the membrane, thus obtaining the Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane;
the retention rate of the prepared nanofiltration membrane on dye molecules with the relative molecular weight higher than 342Da reaches more than 99%, and the water flux can reach 61.5+/-5.5 L.m -2 ·h -1 ·bar -1 。
Further, the preparation method of the nanofiltration membrane comprises the following specific steps:
(1) Pretreatment of PSF ultrafiltration membrane:
placing the PSF ultrafiltration membrane in a sodium sulfite solution with the mass fraction of 1% for light-shielding preservation, soaking the PSF ultrafiltration membrane in the solution with the volume ratio of ethanol to water of 1:1 for 30min to 1h before taking, performing ultrasonic treatment for 5min for activation, repeatedly cleaning the ethanol on the surface of the membrane by deionized water, and then soaking in the deionized water for 6 to 12h for later use;
the existence of the existing commercial PSF ultrafiltration membrane surface anti-corrosion layer can influence the uniform coating of TA, so the pretreatment operation is needed before the surface modification; the adopted ultrasonic wave is the conventional operation in the field, and the inventor does not need to describe the ultrasonic wave repeatedly;
(2) Preparation of Fe by using middle layer modified polysulfone ultrafiltration membrane 3+ TA@PSF composite film
Respectively weighing 0.2g of TA and 0.2g of FeCl 3 Respectively dissolving the powder in 100mL deionized water, immersing pretreated PSF ultrafiltration membrane in 10mL tannic acid solution for 5-10min, taking out membrane, cleaning with deionized water to remove superfluous TA solution on the surface, immersing membrane in 10mL ferric chloride aqueous solution for 5-10min to complete coordination reaction, taking out membrane, and removing superfluous Fe 3 + Repeating the steps for 1-3 times;
(3) Layer-by-layer self-assembly construction buffer transition layer of Ni-Fe MOF/PEI
Weighing 2.666g K 3 Fe(CN) 6 Pouring into a beaker, adding 200mL of deionized water, and preparing into solution A; 1.42g Ni (NO) was weighed out separately 3 ) 2 ·6H 2 O, 1g of polyethyleneimine with mass fraction of 5% and 2.35g of sodium citrate are sequentially dissolved in 200mL of water to obtain solution B;
immersing the film obtained in the step (2) in the solution A and the solution B for 1-5 hours respectively in sequence, repeatedly flushing the film with ethanol and ultrapure water until no residual reagent exists on the surface, airing the surface, and repeating the 2-6 circulation processes according to the flow; finishing the layer-by-layer preparation of the Ni-Fe MOF/PEI buffer layer;
(4) In situ growth of Ni-Fe MOF crystal layer
Taking 100ml of A solution and 200ml of B solution, uniformly mixing the solution by ultrasonic waves, putting the polysulfone membrane obtained in the step (3) after the layer-by-layer growth modification into the mixed solution for 1-5 hours, taking out the polysulfone membrane, and repeatedly cleaning the polysulfone membrane with deionized water and ethanol until no residual reagent exists on the surface;
according to the above flow, the composite membrane after growth is dried at normal temperature, thus the preparation of the Ni-Fe MOF crystal layer on the membrane can be completed, and the target composite nanofiltration membrane is obtained.
The inventor pairsThe modified polysulfone ultrafiltration membrane is subjected to relevant performance detection, and the result shows that the retention rate of the modified composite membrane on dye with the molecular weight of 342-800Da can reach more than 99%. The water flux can reach 61.5+/-5.5 L.m -2 ·h -1 ·bar -1 The retention rate is high, the water flux is high, and compared with most MOFs modified nanofiltration membranes reported in the prior literature (the retention rate is about 99 percent, and the water flux is higher at 25 L.m -2 ·h -1 ·bar -1 Left and right), the water flux and the retention rate are both improved to a great extent.
In the prior art, a single substance is usually selected for modification of the commercial ultrafiltration membrane, such as dopamine hydrochloride or L-dopa, and TA-Fe is selected as the intermediate layer of the application 3+ The advantage is that TA can be adhered to PSF ultrafiltration membrane surface rapidly, TA and Fe 3+ Can uniformly fix Fe by coordination of (A) 2+ Providing a site for the growth of late MOFs. And MOFs materials are self-assembled layer by layer on the modified PSF ultrafiltration membrane: the Ni-Fe MOFs crystal greatly improves the tolerance of the PSF ultrafiltration membrane, and the Ni-Fe MOFs membrane layer has good water stability, does not react with acid and alkali and is insoluble in an organic solvent, so that the requirement on the use environment is reduced, the application range of the Ni-Fe MOFs membrane layer is enlarged, and the Ni-Fe MOFs membrane layer has higher popularization value.
Furthermore, in order to obtain better effect, the time of last soaking in deionized water in the pretreatment of the polysulfone ultrafiltration membrane in the step (1) is preferably 12 hours;
step (2) preparing Fe by using intermediate layer modified polysulfone ultrafiltration membrane 2+ In the case of the TA@PSF composite film, the soaking time in the tannic acid solution and the aqueous ferric chloride solution is preferably 5 minutes.
And (3) when the buffer transition layer is constructed by layer-by-layer self-assembly of the Ni-Fe MOF/PEI, the circulating soaking time of the liquid A and the liquid B is preferably 1.5h, and the circulating soaking times are preferably 3 times.
In the in-situ growth of the Ni-Fe MOF crystal layer in the step (4), the soaking time in the mixed solution of 100ml of solution A and 200ml of solution B is preferably 2h.
In conclusion, the technical scheme of the application assembles a continuous compact Ni-Fe MOFs membrane layer on the surface of the PSF ultrafiltration membrane, better improves the membrane performance, improves the membrane rejection rate, simultaneously maintains higher water flux, and realizes double-improvement of the water flux and the rejection rate.
Drawings
FIG. 1 is a graph showing the retention rate and water flux change of the modified PSF composite membrane prepared in example 2 for different dyes;
FIG. 2 is a graph showing the retention rate and water flux of the modified PSF composite membrane prepared in example 2 for different salt solutions;
FIG. 3 is a graph showing the long-term running stability of the modified PSF composite membrane prepared in example 2;
FIG. 4 is an SEM image of a modified PSF composite membrane prepared in example 2;
FIG. 5 is an XRD pattern of the modified PSF composite film prepared in example 2;
fig. 6 is a FTIR plot of the modified PSF composite film prepared in example 2.
Detailed Description
The present application will be further described with reference to the following examples, which are not to be construed as limiting the scope of the above-described subject matter of the present application to the following examples, but are to be construed as embodying the present application in all manner of techniques based on the above-described subject matter of the present application, except as specifically described below, wherein the following examples are accomplished by conventional techniques. In order to adapt to the nanofiltration membrane evaluation instrument NFMT-01, the area size of the nanofiltration membrane in the following detection is 7.065cm 2 。
Example 1:
a preparation method of a Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane comprises the following specific steps:
(1) Pretreatment of polysulfone ultrafiltration membrane:
placing the PSF ultrafiltration membrane in a sodium sulfite solution with the mass fraction of 1% for light-shielding storage, and placing the PSF ultrafiltration membrane in the volume ratio of ethanol to water of 1:1, soaking in the solution for 30min, performing ultrasonic treatment for 5min for activation, repeatedly cleaning ethanol on the surface of the membrane by deionized water, and then soaking in the deionized water for 12h for standby.
(2) Preparation of Fe by using middle layer modified polysulfone ultrafiltration membrane 2+ TA@PSF composite film
0.2g of TA and 0.2g of TA are weighed out respectivelyg FeCl 3 Respectively dissolving the powder in 100mL deionized water, immersing pretreated PSF ultrafiltration membrane in 10mL tannic acid solution for 5min, taking out membrane, washing with deionized water to remove superfluous TA solution on the surface, and immersing membrane in 10mL FeCl 3 The coordination reaction is completed in the water solution for 5min, the membrane is taken out, and redundant Fe is removed 3+ The above steps were repeated 1 time.
(3) Layer-by-layer self-assembly construction buffer transition layer of Ni-Fe MOF/PEI
Weighing 2.666g K 3 Fe(CN) 6 Pouring into a beaker, adding 200mL of deionized water, and preparing into solution A; 1.42g Ni (NO) was weighed out separately 3 ) 2 ·6H 2 O, 1g of polyethyleneimine with mass fraction of 5% and 2.35g of sodium citrate are sequentially dissolved in 200mL of water to obtain solution B.
Immersing the membrane in the solution A and the solution B for 1.5h respectively, repeatedly washing with ethanol and ultrapure water until no residual reagent exists on the surface, and airing the surface. The process is a cyclic process of preparing the Ni-Fe MOF/PEI buffer layer by layer, and the 2 cyclic processes are repeated according to the above process.
(4) In situ growth of Ni-Fe MOF crystal layer
And (3) taking 100ml of A solution and 200ml of B solution, uniformly mixing the A solution and the B solution by ultrasonic waves, putting the polysulfone membrane obtained in the step (3) after the layer-by-layer growth modification into the mixed solution for 1h, taking out, and repeatedly cleaning the polysulfone membrane with deionized water and ethanol until no residual reagent exists on the surface. And (5) airing the surface water at normal temperature to obtain the target composite nanofiltration membrane, and performing performance test.
Performance test: after the modified nanofiltration membrane is made into a membrane component, the membrane component is put into a nanofiltration membrane evaluator NFMT-01 to start testing, and the area size of the nanofiltration membrane obtained by measurement is 7.065cm 2 ，(7.065×10 -4 m 2 ) The experimental time is 60min, the retention rate and the water flux of methyl blue, congo red, rhodamine B, alizarin red, methyl orange and isatoic red with the concentration of 30ppm are measured, and the result shows that the modified nanofiltration membrane has the retention rate of more than 95 percent and the water flux of 65 L.m for dye molecules with the molecular weight of more than 342Da-800Da -2 ·h -1 ·bar -1 Left and right.
Example 2:
a preparation method of a Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane comprises the following specific steps:
(1) Pretreatment of polysulfone ultrafiltration membrane:
and (3) placing the PSF ultrafiltration membrane in a sodium sulfite solution with the mass fraction of 1% for light-shielding preservation, soaking the PSF ultrafiltration membrane in the solution with the volume ratio of ethanol to water of 1:1 for 30min before taking, performing ultrasonic treatment for 5min for activation, repeatedly cleaning the ethanol on the surface of the membrane by deionized water, and then soaking in the deionized water for 12h for standby.
(2) Preparation of Fe by using middle layer modified polysulfone ultrafiltration membrane 3+ TA@PSF composite film
Respectively weighing 0.2g of TA and 0.2g of FeCl 3 Respectively dissolving the powder in 100mL deionized water, immersing pretreated PSF ultrafiltration membrane in 10mL tannic acid solution for 10min, taking out membrane, washing with deionized water to remove superfluous TA solution on the surface, and immersing membrane in 10mL FeCl 3 The coordination reaction is completed in the water solution for 10min, the membrane is taken out, and redundant Fe is removed 3+ The above steps were repeated 2 times.
(3) Layer-by-layer self-assembly construction buffer transition layer of Ni-Fe MOF/PEI
Weighing 2.666g K 3 Fe(CN) 6 Pouring into a beaker, adding 200mL of deionized water, and preparing into solution A; 1.42g Ni (NO) was weighed out separately 3 ) 2 ·6H 2 O, 1g of polyethyleneimine with mass fraction of 5% and 2.35g of sodium citrate are sequentially dissolved in 200mL of water to obtain solution B.
Immersing the membrane in the solution A and the solution B for 2.5 hours respectively, repeatedly flushing with ethanol and ultrapure water until no reagent remains on the surface, and airing the surface. This process is a cyclic process for the layer-by-layer preparation of the Ni-Fe MOF/PEI buffer layer. The 3 cycles were repeated as described above.
(4) In situ growth of Ni-Fe MOF crystal layer
Mixing the solution A and the solution B according to the volume ratio of 1:2, putting the polysulfone membrane subjected to layer-by-layer growth modification into the mixed solution for 2 hours, taking out, and repeatedly cleaning with deionized water and ethanol until no residual reagent exists on the surface. After the surface moisture is dried at normal temperature, the target composite nanofiltration membrane is obtained, and performance test is carried out:
performance test: after the modified nanofiltration membrane is made into a membrane module, the membrane module is put into a nanofiltration membrane evaluation instrument NFMT-01 to start testing, and the membrane area is measured to be 7.065cm 2 ，(7.065×10 -4 m 2 ) The experimental time is 60min, the retention rate and the water flux of methyl blue, congo red, rhodamine B, alizarin red, methyl orange and isatoic red with the concentration of 30ppm are measured, and the result shows that the modified nanofiltration membrane has the retention rate of more than 99 percent and the water flux of 61.5+/-5.5 L.m for dye molecules with the molecular weight of 342Da-800Da -2 ·h -1 ·bar -1 Compared with the existing MOFs modified nanofiltration membrane, the flux and the retention rate are greatly improved.
Example 3
A preparation method of a Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane comprises the following specific steps:
(1) Pretreatment of polysulfone ultrafiltration membrane:
and (3) placing the PSF ultrafiltration membrane in a sodium sulfite solution with the mass fraction of 1% for light-shielding preservation, soaking the PSF ultrafiltration membrane in the solution with the volume ratio of ethanol to water of 1:1 for 30min before taking, performing ultrasonic treatment for 5min for activation, repeatedly cleaning the ethanol on the surface of the membrane by deionized water, and then soaking in the deionized water for 12h for standby.
(2) Preparation of Fe by using middle layer modified polysulfone ultrafiltration membrane 3+ TA@PSF composite film
Respectively weighing 0.2g of TA and 0.2g of FeCl 3 Respectively dissolving the powder in 100mL deionized water, immersing pretreated PSF ultrafiltration membrane in 10mL tannic acid solution for 5min, taking out membrane, washing with deionized water to remove superfluous TA solution on the surface, and immersing membrane in 10mL FeCl 3 The coordination reaction is completed in the water solution for 5min, the membrane is taken out, and redundant Fe is removed 3+ Repeating the above steps for 3 times.
(3) Layer-by-layer self-assembly construction buffer transition layer of Ni-Fe MOF/PEI
Weighing 2.666g K 3 Fe(CN) 6 Pouring into a beaker, adding 200mL of deionized water, and preparing into solution A; and then respectively1.42g Ni (NO) was weighed out 3 ) 2 ·6H 2 O, 1g of polyethyleneimine with mass fraction of 5% and 2.35g of sodium citrate are sequentially dissolved in 200mL of water to obtain solution B. Immersing the membrane in the solution A and the solution B for 5 hours respectively, repeatedly flushing with ethanol and ultrapure water until no reagent remains on the surface, and airing the surface. This process is a cyclic process of layer-by-layer growth of Ni-Fe MOFs. The 4-cycle process was repeated as per the procedure described above.
(4) In situ growth of Ni-Fe MOF crystal layer
And (3) taking 100ml of A solution and 200ml of B solution, uniformly mixing the A solution and the B solution by ultrasonic waves, putting the polysulfone membrane obtained in the step (3) after the layer-by-layer growth modification into the mixed solution for 3 hours, taking out the polysulfone membrane, and repeatedly cleaning the polysulfone membrane with deionized water and ethanol until no residual reagent exists on the surface. And (5) airing the surface water at normal temperature to obtain the target composite nanofiltration membrane, and performing performance test.
Performance test: after the modified nanofiltration membrane is made into a membrane component, the membrane component is put into a nanofiltration membrane evaluator NFMT-01 to start testing, and the membrane area is measured to be 7.065cm 2 ，(7.065×10 -4 m 2 ) The test time is 60min, the retention rate and the water flux of methyl blue, congo red, rhodamine B, alizarin red, methyl orange and isatoic with the concentration of 30ppm are measured, and the result shows that the modified nanofiltration membrane has the retention rate of more than 99 percent and the water flux of 55 L.m for dye molecules with the molecular weight of 342Da-800Da -2 ·h -1 ·bar -1 Left and right.
Experimental example
In addition, the inventors conducted a correlation test on the modified polysulfone ultrafiltration membrane obtained in example 2, and the results are shown below:
and carrying out nanofiltration performance test on the modified PSF composite membrane. For 6 dyes of methyl blue, congo red, rhodamine B, alizarin red, methyl orange and isatoic at a concentration of 30ppm and Al at a concentration of 1g/L at a pressure of 4bar 2 (SO 4 ) 3 、MgCl 2 、Na 2 SO 4 、MgSO 4 The retention test of five substances of NaCl is carried out, and FIGS. 1 and 2 are graphs of retention rate of 6 dyes and 5 salts of the modified PSF composite membrane and water flux comparison, so that the composite can be foundThe rejection rate of the membrane to dye with molecular weight above 342Da is above 99%, and the rejection rate of Ni-Fe MOFs is less than 0.51nm, so that the rejection rate of the membrane to methyl orange is 76.78%, the rejection rate of the membrane to small molecular dye isatin is 60.42%, and the rejection rate of the membrane to selected 5 salts is below 50%. Compared with most MOFs modified nanofiltration membranes reported in the prior literature (the flux is higher and is 25 L.m -2 ·h -1 ·bar -1 About, the retention rate is higher and is about 99 percent), the water flux is greatly improved to 61.5+/-5.5 L.m under the premise of higher retention rate -2 ·h -1 ·bar -1 Left and right.
Also we performed long-term running stability tests on modified PSF composite membranes (as shown in fig. 3). After long-acting operation for 14 hours, the rejection rate of the composite membrane to Congo red is always stabilized to be more than 99%, and the water flux is controlled by 61 L.m -2 ·h -1 ·bar -1 Down to 54 L.m -2 ·h -1 ·bar -1 . The reason why the water flux decrease amplitude is large is that: because the initial water flux of the composite membrane is higher, congo red is easy to physically accumulate on the surface of the composite membrane to block part of pore channels, so that the water flux is reduced. After 14 hours, the device is disassembled, the membrane surface is washed clean, then nanofiltration performance test is carried out, and the water flux is restored to 58 L.m -2 ·h -1 ·bar -1 The retention rate is still more than 99%.
Fig. 4 is an SEM image of the modified PSF composite membrane prepared in example 2, in which fig. 1 is a PSF base membrane, and in a scanning electron microscope image, it can be seen that pores larger than 20nm are distributed on the surface of the PSF ultrafiltration membrane. 2 is Fe 3+ TA@PSF composite membranes, which smooth the membrane surface and have reduced pore size compared to the PSF-based membranes, due to TA and Fe 2+ The complex formed adheres to the membrane surface, resulting in smaller membrane pores. 3 is a nanofiltration composite membrane prepared by an in-situ growth method, and because the rigidity of Ni-Fe MOFs is high, the problem of large-area cracking of the Ni-Fe MOFs crystal layer can occur when the nano-filtration composite membrane grows on a flexible PSF substrate. 4 is a nanofiltration composite membrane prepared by a layer-by-layer growth mode after PEI is added, the cracking problem is solved, but most crystals do not form a uniform cube structure due to the short growth time. 5 is to extend the reaction by in-situ growth based on 4The cracking problem was solved by time-prepared composite membranes (i.e., the membranes obtained in example 2), and the Ni-Fe MOFs crystals were of uniform cubic structure, consistent with literature reports.
Fig. 5 is an XRD pattern of the modified PSF composite film prepared in example 2, and new characteristic peaks were observed at 17 °, 24 °, 35 °, 40 °, 43 °, 50 °, 53 °, 57 °, 65 °, 68 ° of the composite film after the growth of the ni—fe MOFs crystal layer. After PEI addition, there was no shift in peak position but a slight decrease in height. By comparison, the characteristic peaks are similar to those of Ni-Fe MOFs crystals and are highly similar to those of standard cards 46-0906, so that the existence of a Ni-Fe MOFs crystal layer on the modified PSF composite film can be further illustrated.
FIG. 6 is a FTIR view of a modified PSF composite film prepared in example 2, which may be at 1293cm first -1 An absorption peak was observed at 1245cm, an asymmetric stretch peak ascribed to the S-O group -1 The strong absorption peak is an asymmetric telescopic vibration absorption peak of the aromatic ether, and the two absorption peaks are special groups of PSF base film components. At 1730cm -1 The absorption peak at this point is attributed to the stretching vibration of the carbonyl group (C=O) in TA at 722cm -1 The absorption peak at the position belongs to the telescopic vibration of Fe-O, 1350cm -1 And 1478cm -1 The peak appeared at this point is TA-Fe 3+ The catechol ring in the complex stretches out and draws back, which indicates TA-Fe 3+ The complex reaction occurs on the membrane surface and is successfully loaded on the membrane surface. At 2089cm -1 The strong absorption peak appearing at this point belongs to the absorption vibration peak of c≡n. At 589cm -1 A new peak appears at the position, and the peak belongs to the coordination absorption vibration peak of the pure Ni-Fe MOFs, which indicates that the Ni-Fe PBA has been successfully constructed to Fe 3+ TA@PSF composite film. By comparing the infrared spectrogram of the Ni-Fe PBA powder with that of PEI@Ni-Fe MOFs powder, the powder is found to be located at 2165cm -1 The extensional vibration peak generated by Ni-NC is reduced because of the abundance of-NH in PEI 3 Priority and Ni 2+ Coordination, resulting in a decrease in the coordination sites of Ni-NC and therefore a decrease in the intensity of the infrared peak, indicates that PEI has been successfully incorporated into Ni-Fe MOFs crystals. The presence of the above mentioned important groups in the final nanofiltration membrane suggests PEI@Ni-Fe MOFs/TA-Fe 3+ Successful preparation of PS nanofiltration membranes.
The technical features of the above embodiments may be combined in any desired manner, and for brevity, all of the possible combinations of the technical features of the above embodiments may not be described, however, as long as there is no contradiction between the combinations of the technical features, all of which should be considered as being within the scope of the description, the description of the above embodiments may be used to help understand the principles and methods of the present application. The above embodiments are not intended to be exclusive and should not be construed as limiting the application. Also, as will be apparent to those of ordinary skill in the art, many modifications, both to specific embodiments and to scope of the application, are possible in accordance with the principles and methods of the application.
Claims (6)
1. A preparation method of a Ni-Fe bimetallic MOF crystal layer polysulfone composite nanofiltration membrane is characterized by comprising the following steps: the method comprises the following specific steps:
(1) Pretreatment of PSF ultrafiltration membrane:
placing the PSF ultrafiltration membrane in a sodium sulfite solution with the mass fraction of 1% for light-shielding preservation, soaking the PSF ultrafiltration membrane in the solution with the volume ratio of ethanol to water of 1:1 for 30min to 1h before taking, performing ultrasonic treatment for 5min for activation, repeatedly cleaning the ethanol on the surface of the membrane by deionized water, and then soaking in the deionized water for 6 to 12h for later use;
(2) Preparation of Fe by using middle layer modified polysulfone ultrafiltration membrane 3+ TA@PSF composite film
Respectively weighing 0.2g of TA and 0.2g of FeCl 3 Respectively dissolving the powder in 100mL deionized water, immersing pretreated PSF ultrafiltration membrane in 10mL tannic acid solution for 5-10min, taking out membrane, cleaning with deionized water to remove superfluous TA solution on the surface, immersing membrane in 10mL ferric chloride aqueous solution for 5-10min to complete coordination reaction, taking out membrane, and removing superfluous Fe 3+ Repeating the steps for 1-3 times;
(3) Layer-by-layer self-assembly construction buffer transition layer of Ni-Fe MOF/PEI
Weighing 2.666g K 3 Fe(CN) 6 Pouring into a beaker, adding 200mL of deionized water, and preparing into solution A; 1.42g Ni (NO) was weighed out separately 3 ) 2 ·6H 2 O, 1g of polyethyleneimine with mass fraction of 5% and 2.35g of sodium citrate are sequentially dissolved in 200mL of water to obtain solution B;
immersing the film obtained in the step (2) in the solution A and the solution B for 1-5 hours respectively in sequence, repeatedly flushing the film with ethanol and ultrapure water until no residual reagent exists on the surface, airing the surface, and repeating the 2-6 circulation processes according to the flow; finishing the layer-by-layer preparation of the Ni-Fe MOF/PEI buffer layer;
(4) In situ growth of Ni-Fe MOF crystal layer
Taking 100ml of A solution and 200ml of B solution, uniformly mixing the solution by ultrasonic waves, putting the polysulfone membrane obtained in the step (3) after the layer-by-layer growth modification into the mixed solution for 1-5 hours, taking out the polysulfone membrane, and repeatedly cleaning the polysulfone membrane with deionized water and ethanol until no residual reagent exists on the surface;
according to the above flow, the composite membrane after growth is dried at normal temperature, thus the preparation of the Ni-Fe MOF crystal layer on the membrane can be completed, and the target composite nanofiltration membrane is obtained.
2. The preparation method of the Ni-Fe bi-metal MOF crystal layer polysulfone composite nanofiltration membrane according to claim 1, which is characterized by comprising the following steps:
the last time of soaking in deionized water in the pretreatment of the polysulfone ultrafiltration membrane in the step (1) is 12 hours.
3. The preparation method of the Ni-Fe bi-metal MOF crystal layer polysulfone composite nanofiltration membrane according to claim 1, which is characterized by comprising the following steps:
step (2) preparing Fe by using intermediate layer modified polysulfone ultrafiltration membrane 3+ In the case of the TA@PSF composite film, the soaking time in the tannic acid solution and the ferric chloride aqueous solution was 5min.
4. The preparation method of the Ni-Fe bi-metal MOF crystal layer polysulfone composite nanofiltration membrane according to claim 1, which is characterized by comprising the following steps:
and (3) when the buffer transition layer is constructed by layer-by-layer self-assembly of Ni-Fe MOF/PEI, the circulating soaking time of the solution A and the solution B is 1.5h, and the circulating soaking times are 3 times.
5. The preparation method of the Ni-Fe bi-metal MOF crystal layer polysulfone composite nanofiltration membrane according to claim 1, which is characterized by comprising the following steps: and (4) soaking the Ni-Fe MOF crystal layer in the mixed solution for 2 hours during in-situ growth of the Ni-Fe MOF crystal layer.
6. The Ni-Fe bi-metal MOF crystal layer polysulfone composite nanofiltration membrane obtained by the preparation method according to any one of claims 1-5.
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| KR20160090167A (en) * | 2015-01-21 | 2016-07-29 | 서울대학교산학협력단 | Coating material for water treatment membrane and water treatment membrane coated with the same |
| CN109603565A (en) * | 2018-12-12 | 2019-04-12 | 浙江工业大学 | Method for synthesizing metal organic framework composite membrane by auxiliary deposition of catechol compound |
| CN110038450A (en) * | 2019-04-22 | 2019-07-23 | 浙江工业大学 | A kind of preparation method of super hydrophilic carbon nanotube perforated membrane |
| WO2019156635A1 (en) * | 2018-02-08 | 2019-08-15 | Nanyang Technological University | Graphene frameworks membranes for separation of immiscible liquids |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20160090167A (en) * | 2015-01-21 | 2016-07-29 | 서울대학교산학협력단 | Coating material for water treatment membrane and water treatment membrane coated with the same |
| WO2019156635A1 (en) * | 2018-02-08 | 2019-08-15 | Nanyang Technological University | Graphene frameworks membranes for separation of immiscible liquids |
| CN109603565A (en) * | 2018-12-12 | 2019-04-12 | 浙江工业大学 | Method for synthesizing metal organic framework composite membrane by auxiliary deposition of catechol compound |
| CN110038450A (en) * | 2019-04-22 | 2019-07-23 | 浙江工业大学 | A kind of preparation method of super hydrophilic carbon nanotube perforated membrane |
Non-Patent Citations (2)
| Title |
|---|
| Efficient Helium Separation with Two-Dimensional Metal–Organic Framework Fe/Ni-PTC: A Theoretical Study;Wang Jingyuan等;membranes;第11卷;927 * |
| 基于金属-多酚络合物复合纳滤膜的构筑及其在水处理中的应用;肖益蓉;中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑(第2期);B016-67 * |
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