CN114870637A - Preparation method of strong hydrophobic composite membrane - Google Patents
Preparation method of strong hydrophobic composite membrane Download PDFInfo
- Publication number
- CN114870637A CN114870637A CN202210513073.5A CN202210513073A CN114870637A CN 114870637 A CN114870637 A CN 114870637A CN 202210513073 A CN202210513073 A CN 202210513073A CN 114870637 A CN114870637 A CN 114870637A
- Authority
- CN
- China
- Prior art keywords
- zif
- composite membrane
- solution
- block amide
- polyether block
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000012528 membrane Substances 0.000 title claims abstract description 57
- 230000002209 hydrophobic effect Effects 0.000 title claims abstract description 53
- 239000002131 composite material Substances 0.000 title claims abstract description 41
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- 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 claims abstract description 85
- 239000013154 zeolitic imidazolate framework-8 Substances 0.000 claims abstract description 81
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 75
- 229920002614 Polyether block amide Polymers 0.000 claims abstract description 61
- 239000000243 solution Substances 0.000 claims abstract description 38
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 claims abstract description 27
- 239000004695 Polyether sulfone Substances 0.000 claims abstract description 25
- 229920006393 polyether sulfone Polymers 0.000 claims abstract description 25
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 claims abstract description 24
- 238000005266 casting Methods 0.000 claims abstract description 22
- 238000001035 drying Methods 0.000 claims abstract description 22
- 150000003751 zinc Chemical class 0.000 claims abstract description 19
- 238000003756 stirring Methods 0.000 claims abstract description 15
- 239000007788 liquid Substances 0.000 claims abstract description 14
- 239000000725 suspension Substances 0.000 claims abstract description 14
- 239000011259 mixed solution Substances 0.000 claims abstract description 12
- 150000002460 imidazoles Chemical class 0.000 claims abstract description 11
- 239000003446 ligand Substances 0.000 claims abstract description 10
- 238000005406 washing Methods 0.000 claims abstract description 10
- LXBGSDVWAMZHDD-UHFFFAOYSA-N 2-methyl-1h-imidazole Chemical compound CC1=NC=CN1 LXBGSDVWAMZHDD-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000012266 salt solution Substances 0.000 claims abstract description 9
- 239000006185 dispersion Substances 0.000 claims abstract description 8
- 238000002156 mixing Methods 0.000 claims abstract description 8
- 238000007872 degassing Methods 0.000 claims abstract description 7
- 238000007790 scraping Methods 0.000 claims abstract description 7
- 238000009210 therapy by ultrasound Methods 0.000 claims abstract description 6
- -1 polytetrafluoroethylene Polymers 0.000 claims abstract description 5
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims abstract description 5
- 239000004810 polytetrafluoroethylene Substances 0.000 claims abstract description 5
- 238000006243 chemical reaction Methods 0.000 claims abstract description 4
- 229940079865 intestinal antiinfectives imidazole derivative Drugs 0.000 claims abstract description 4
- 238000000034 method Methods 0.000 claims description 16
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 15
- LJUQGASMPRMWIW-UHFFFAOYSA-N 5,6-dimethylbenzimidazole Chemical group C1=C(C)C(C)=CC2=C1NC=N2 LJUQGASMPRMWIW-UHFFFAOYSA-N 0.000 claims description 6
- 239000004745 nonwoven fabric Substances 0.000 claims description 5
- XIOUDVJTOYVRTB-UHFFFAOYSA-N 1-(1-adamantyl)-3-aminothiourea Chemical group C1C(C2)CC3CC2CC1(NC(=S)NN)C3 XIOUDVJTOYVRTB-UHFFFAOYSA-N 0.000 claims description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N EtOH Substances CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 23
- 238000000926 separation method Methods 0.000 description 23
- 230000004907 flux Effects 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 238000005373 pervaporation Methods 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- 238000005457 optimization Methods 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 238000011161 development Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 238000011068 loading method Methods 0.000 description 4
- 239000011159 matrix material Substances 0.000 description 4
- 239000012621 metal-organic framework Substances 0.000 description 4
- 230000007547 defect Effects 0.000 description 3
- 238000011049 filling Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 125000001165 hydrophobic group Chemical group 0.000 description 3
- 230000001965 increasing effect Effects 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000002708 enhancing effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000013110 organic ligand Substances 0.000 description 2
- 239000005416 organic matter Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 238000001878 scanning electron micrograph Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 239000013153 zeolitic imidazolate framework Substances 0.000 description 2
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000012527 feed solution Substances 0.000 description 1
- 238000000855 fermentation Methods 0.000 description 1
- 230000004151 fermentation Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910021645 metal ion Inorganic materials 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 229920000570 polyether Polymers 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
Images
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
-
- 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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/10—Supported membranes; Membrane supports
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- 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
-
- 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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/04—Hydrophobization
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/38—Hydrophobic membranes
-
- 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
- Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
- Y02C20/00—Capture or disposal of greenhouse gases
- Y02C20/40—Capture or disposal of greenhouse gases of CO2
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention discloses a preparation method of a strong hydrophobic composite membrane, which comprises the steps of respectively dissolving 2-methylimidazole and zinc salt in anhydrous methanol to obtain a ligand solution and a zinc salt solution; then, quickly pouring the zinc salt solution into the ligand solution, reacting at room temperature, centrifuging, washing and drying to obtain ZIF-8; ultrasonically dispersing the obtained ZIF-8 in absolute methanol to obtain a uniform ZIF-8 dispersion liquid; dissolving imidazole derivatives in absolute methanol, dropwise adding a proper amount of triethylamine, and then quickly pouring the obtained ZIF-8 dispersion liquid into the anhydrous methanol to obtain a mixed solution; transferring to a polytetrafluoroethylene container, placing in an air-blast drying oven, fully reacting, centrifuging, washing and drying to obtain the strongly hydrophobic ZIF-8; dispersing the obtained strongly hydrophobic ZIF-8 in n-butanol to obtain a suspension, mixing and stirring the suspension and the polyether block amide solution for full reaction, and performing ultrasonic treatment and standing degassing to obtain a strongly hydrophobic ZIF-8/polyether block amide mixed solution; and casting to a polyether sulfone supporting layer, scraping a membrane, and drying to obtain the ZIF-8/polyether block amide composite membrane with strong hydrophobicity.
Description
Technical Field
The invention belongs to the technical field of materials, and particularly relates to a preparation method of a strong hydrophobic composite membrane.
Background
At present, resource shortage and environmental deterioration have attracted global high attention, and become a worldwide problem which needs to be solved urgently, and renewable, novel and clean energy has become a research hotspot of all countries in the world. The bio-ethanol can play a positive role in the sustainable development of energy supply as a petroleum substitute, and the use of the mixed gasoline containing 10 percent of ethanol can reduce the emission of harmful gases of automobiles. The bioethanol becomes a representative of replacing new energy, however, the water content in the biological fermentation liquid is up to more than 90%, and the energy consumption for enriching and concentrating the bioethanol by adopting a rectification method is too large. In recent years, the development of membrane separation technology provides possibility for low-energy-consumption refining of bioethanol. The pervaporation technology is used as a typical liquid mixture membrane separation method, takes steam pressure difference as a driving force, is not limited by gas-liquid balance, and is widely applied to aspects of organic matter dehydration, organic matter recovery and the like.
The development of efficient separation membranes is the key to improving pervaporation performance, and the development of membrane materials is always the core. Metal-organic frameworks (MOFs) are porous materials formed by connecting metal ions or ion clusters and organic ligands, and have the characteristics of rich chemical composition, large specific surface area, diversified topological structure, adjustable pore channels and the like. In addition, the MOFs material has the characteristic of selective adsorption on specific liquid molecules, becomes a new separation membrane material, and plays an important role in the separation of gas and liquid mixtures.
ZIF-8, which is a typical representative of Zeolitic Imidazolate Frameworks (ZIFs), is an SOD structure. The composite membrane has good thermal stability and chemical stability, high specific surface area and porosity, adjustable pore structure and chemical properties, and is often used as a membrane material for gas or liquid separation.
Although the preparation method of ZIF-8 is simple and the comprehensive performance is good, in the actual removal of ethanol in a low-concentration ethanol aqueous solution, the operation conditions have great influence on the separation factor and the permeation flux of the membrane, and other preparation conditions are ignored.
Disclosure of Invention
The invention aims to provide a preparation method of a strong-hydrophobicity ZIF-8/polyether block amide composite membrane, which promotes the compatibility of filling particles ZIF-8 with a polymer by enhancing the hydrophobicity of the filling particles ZIF-8, eliminates interface defects, improves the separation performance of the composite membrane, remarkably improves the hydrophobicity and the hydrophilicity of the composite membrane, and optimizes the alcohol-water separation performance.
In order to achieve the purpose, the technical scheme is as follows:
a preparation method of a strong hydrophobic composite membrane comprises the following steps:
(1) respectively dissolving 2-methylimidazole and zinc salt in absolute methanol to obtain a ligand solution and a zinc salt solution; then, quickly pouring the zinc salt solution into the ligand solution, reacting at room temperature, centrifuging, washing and drying to obtain ZIF-8;
(2) ultrasonically dispersing the obtained ZIF-8 in absolute methanol to obtain a uniform ZIF-8 dispersion liquid; dissolving imidazole derivatives in absolute methanol, dropwise adding a proper amount of triethylamine, and then quickly pouring the obtained ZIF-8 dispersion liquid into the anhydrous methanol to obtain a mixed solution; transferring to a polytetrafluoroethylene container, placing in an air-blast drying oven, fully reacting, centrifuging, washing and drying to obtain the strongly hydrophobic ZIF-8;
(3) dispersing the obtained strongly hydrophobic ZIF-8 in n-butanol to obtain a suspension, mixing and stirring the suspension and the polyether block amide solution for full reaction, and performing ultrasonic treatment and standing degassing to obtain a strongly hydrophobic ZIF-8/polyether block amide mixed solution;
(4) and casting the obtained ZIF-8/polyether block amide mixed solution with strong hydrophobicity to a polyether sulfone supporting layer, scraping the membrane, and drying to obtain the ZIF-8/polyether block amide composite membrane with strong hydrophobicity.
According to the scheme, in the step (1), the molar ratio of the 2-methylimidazole to the zinc salt to the anhydrous methanol is 1 (7-9) to (600-800). The optimization is 1:8: 700.
According to the scheme, the molar ratio of ZIF-8, the imidazole derivative, the triethylamine and the anhydrous methanol in the step (2) is 1 (1.5-2.0) to (1.8-2.2) to (180-200). The optimization is 1:1:2: 200.
According to the scheme, the polyether block amide solution in the step (3) is prepared by the following method:
dissolving polyether block amide in n-butyl alcohol, and fully stirring to obtain a polyether block amide solution with the weight percent of 5-8%; the polyether block amide is PEBAX 2533.
According to the scheme, in the step (3), the mass ratio of the strongly hydrophobic ZIF-8 to the polyether block amide is 1: (7-39). The optimization is 1: 9.
According to the scheme, the polyether sulfone support layer in the step (4) is prepared by the following method:
dissolving the polyether sulfone in N, N-dimethylformamide, fully stirring to obtain a 15-20 wt% polyether sulfone solution, and casting to a non-woven fabric to obtain a polyether sulfone supporting layer.
According to the scheme, the doping amount of the strongly hydrophobic ZIF-8 in the strongly hydrophobic ZIF-8/polyether block amide composite membrane obtained in the step (4) is less than or equal to 10 wt%.
According to the scheme, the zinc salt is zinc nitrate hexahydrate.
According to the scheme, the imidazole derivative is 5, 6-dimethylbenzimidazole.
According to the invention, ZIF-8 is prepared firstly, and then 2-methylimidazole in the ZIF-8 outer layer is exchanged by adopting imidazole derivative 5, 6-dimethylbenzimidazole which is an organic ligand with a hydrophobic group, so that ZIF-8 is more hydrophobic. And then preparing the strong hydrophobic ZIF-8/polyether block amide composite membrane by using a solution blending-casting method. The filling particles in the composite membrane are uniformly dispersed in the polymer, no obvious interface defect exists, and the pervaporation separation performance is effectively optimized.
According to the invention, from the viewpoints of enhancing the hydrophobicity of ZIF-8, eliminating interface defects and improving separation performance, the post-synthesis modification is carried out on fresh ZIF-8, and a hydrophobic group is introduced to obtain the strongly hydrophobic ZIF-8. Due to the introduction of various hydrophobic groups into the ZIF-8 outer layer, more ethanol molecules can be adsorbed, the hydrophobic degree of the membrane is improved, the selective adsorption-diffusion of the ethanol molecules can be promoted, and the permeability and the separation factor of the ethanol molecules are improved.
Compared with the prior art, the invention has the following beneficial effects:
compared with the original PEBAX membrane, the flux and the separation factor of the strong hydrophobic ZIF-8/polyether block amide composite membrane are remarkably improved, and the 'balance' effect between the flux and the separation factor is broken. The result shows that the strong hydrophobic ZIF-8/polyether block amide composite membrane has great application potential in the aspect of dealcoholization through pervaporation.
The invention utilizes the characteristic of rich chemical compositions of MOFs to carry out chemical post-synthesis modification on the material to exchange the ligand of the material, and the composite membrane prepared from the material, a polyether block amide matrix and a polyether sulfone supporting layer is used for removing and recovering ethanol in low-concentration ethanol solution, thereby improving the separation performance of ethanol/water. The membrane preparation process is simple, optimizes the separation performance of the composite membrane, and has strong competitive advantage when being applied to the separation of ethanol and water.
Drawings
FIG. 1: XRD pattern of strongly hydrophobic ZIF-8 obtained in example 1.
FIG. 2: water contact angle plot of the strongly hydrophobic ZIF-8 obtained in example 1.
FIG. 3: SEM image of the polyether block amide composite membrane with 10 wt% of the strongly hydrophobic ZIF-8 content obtained in example 1.
FIG. 4: the pervaporation performance of the polyether block amide composite membrane with the strong hydrophobic ZIF-8 content of 10 wt% obtained in example 1 and the membranes prepared in comparative examples 1 and 2 is shown on the left, and the pervaporation test chart with different strong hydrophobic ZIF-8 loading amounts in example 1 is shown on the right.
Detailed Description
The following examples further illustrate the technical solutions of the present invention, but should not be construed as limiting the scope of the present invention.
In a specific embodiment, a preparation method of a strong hydrophobic composite membrane is provided, which comprises the following steps:
(1) respectively dissolving 2-methylimidazole and zinc salt in absolute methanol to obtain a ligand solution and a zinc salt solution; then, quickly pouring the zinc salt solution into the ligand solution, reacting at room temperature, centrifuging, washing and drying to obtain ZIF-8;
(2) ultrasonically dispersing the obtained ZIF-8 in absolute methanol to obtain a uniform ZIF-8 dispersion liquid; dissolving imidazole derivatives in absolute methanol, dropwise adding a proper amount of triethylamine, and then quickly pouring the obtained ZIF-8 dispersion liquid into the anhydrous methanol to obtain a mixed solution; transferring to a polytetrafluoroethylene container, placing in an air-blast drying oven, fully reacting, centrifuging, washing and drying to obtain the strongly hydrophobic ZIF-8;
(3) dispersing the obtained strongly hydrophobic ZIF-8 in n-butanol to obtain a suspension, mixing and stirring the suspension and the polyether block amide solution for full reaction, and performing ultrasonic treatment and standing degassing to obtain a strongly hydrophobic ZIF-8/polyether block amide mixed solution;
(4) and casting the obtained ZIF-8/polyether block amide mixed solution with strong hydrophobicity to a polyether sulfone supporting layer, scraping the membrane, and drying to obtain the ZIF-8/polyether block amide composite membrane with strong hydrophobicity.
Specifically, in the step (1), the molar ratio of the 2-methylimidazole to the zinc salt to the anhydrous methanol is 1 (7-9) to (600-800). The optimization is 1:8: 700.
Specifically, the molar ratio of ZIF-8, imidazole derivative, triethylamine and absolute methanol in the step (2) is 1 (1.5-2.0) to (1.8-2.2) to (180-200). The optimization is 1:1:2: 200.
Specifically, the polyether block amide solution in the step (3) is prepared by the following method:
dissolving polyether block amide in n-butyl alcohol, and fully stirring to obtain a polyether block amide solution with the weight percent of 5-8%; the polyether block amide is PEBAX 2533.
Specifically, in the step (3), the mass ratio of the strongly hydrophobic ZIF-8 to the polyether block amide is 1: (7-39). The optimization is 1: 9.
Specifically, the polyethersulfone support layer in the step (4) is prepared by the following method:
dissolving the polyether sulfone in N, N-dimethylformamide, fully stirring to obtain a 15-20 wt% polyether sulfone solution, and casting to a non-woven fabric to obtain a polyether sulfone supporting layer.
Specifically, the doping amount of the strongly hydrophobic ZIF-8 in the strongly hydrophobic ZIF-8/polyether block amide composite membrane obtained in the step (4) is less than or equal to 10 wt%.
Specifically, the zinc salt is zinc nitrate hexahydrate.
Specifically, the imidazole derivative is 5, 6-dimethylbenzimidazole.
Example 1:
step 1: 2-methylimidazole and zinc nitrate hexahydrate are respectively dissolved in absolute methanol, and the molar ratio of the three is 1:8: 700. And (3) quickly pouring the zinc salt solution into the ligand solution, reacting for 1h at room temperature, centrifuging, washing and drying to obtain the ZIF-8.
Step 2: dispersing the ZIF-8 obtained in the step 1 into absolute methanol, and performing ultrasonic treatment for 1h to obtain a uniform suspension; dissolving 5, 6-dimethylbenzimidazole in absolute methanol, dropwise adding triethylamine, and then quickly pouring ZIF-8 uniform suspension into the mixture; and transferring the mixed solution to a polytetrafluoroethylene container, placing the container in an air-blast drying oven, fully reacting, centrifuging, washing and drying to obtain the strongly hydrophobic ZIF-8. The XRD pattern and the water contact angle pattern are shown in figures 1 and 2 in detail.
And 3, step 3: dispersing 8g of polyether sulfone in N, N-dimethylformamide, heating and stirring until the polyether sulfone is completely dissolved to obtain a casting solution with the mass fraction of 20 wt%, and casting the casting solution to a non-woven fabric to obtain a PES supporting layer.
And 4, step 4: 2g of the polyether block amide PEBAX 2533 are dispersed in n-butanol and stirred with heating until complete dissolution, giving a matrix solution with a mass fraction of 5 wt%.
And 5: and (3) dispersing the strongly hydrophobic ZIF-8 with different masses in the step (2) in n-butyl alcohol, and performing ultrasonic treatment to obtain a uniform suspension. And (4) mixing the dispersed suspension with the polyether block amide PEBAX 2533 solution in the step (4), stirring and fully mixing, standing and degassing to obtain a casting solution.
Step 6: and (3) casting the casting solution in the step (5) to a PES supporting layer in the step (3), and performing film scraping and drying to obtain six composite films with different strong hydrophobic ZIF-8 contents (respectively 0 wt%, 2.5 wt%, 5 wt%, 7.5 wt%, 10 wt% and 12.5 wt%). An SEM image of the polyether block amide composite membrane in which the strongly hydrophobic ZIF-8 content was 10 wt% is shown in fig. 3.
FIG. 1 shows that the ZIF-8 particles modified with 5, 6-dimethylbenzimidazole maintained the original crystal structure of the ZIF-8 particles without disruption.
FIG. 2 shows that 5, 6-dimethylbenzimidazole-modified ZIF-8 particles have enhanced hydrophobicity.
FIG. 3 shows that 5, 6-dimethylbenzimidazole-modified ZIF-8 particles have good compatibility with PEBAX 2533 matrix, and the modified ZIF-8 particles have good dispersibility.
Comparative example 1
Ultrasonically dispersing ZIF-8 to n-butyl alcohol to obtain a suspension; mixing the dispersed suspension with 5 wt% of polyether block amide PEBAX 2533 solution, stirring and fully mixing, standing and degassing to obtain a casting solution; and then, casting the film onto the supporting layer in the step 3, and scraping and drying to obtain the ZIF-8/PEBAX 2533 composite film.
Comparative example 2
Step 1: dispersing 8g of polyether sulfone in N, N-dimethylformamide, heating and stirring until the polyether sulfone is completely dissolved to obtain a casting solution with the mass fraction of 20 wt%, and casting the casting solution to a non-woven fabric to obtain a PES supporting layer.
Step 2: dispersing 2g of polyether block amide PEBAX 2533 in n-butanol, heating and stirring until the polyether block amide PEBAX 2533 is completely dissolved to obtain a matrix solution with the mass fraction of 5 wt%, and standing and degassing to obtain a casting solution.
And step 3: and (3) casting the casting solution in the step (2) to the PES supporting layer in the step (1), and scraping and drying to obtain the PEBAX 2533 membrane.
The different membranes prepared in example 1 were subjected to pervaporation tests in a laboratory-designed plant, downstream of the membrane a vacuum environment. The operating temperatures were 30 ℃ respectively, and the feed solution composition was ethanol/water (5/95 wt%). The total flux increased with increasing content of modified ZIF-8, while the separation factor reached a maximum at a loading of 10%. See fig. 4 (right) for details.
FIG. 4 (left) shows that the polyether block amide composite membrane having 10 wt% of strongly hydrophobic ZIF-8 prepared in example 1 has a total flux of 312g/m 2 h, separation factor 15.95. The total flux of the ZIF-8/polyether block amide composite membrane prepared in the comparative example 1 is 269g/m 2 h, separation factor 13.85. The total flux of the original polyether block amide composite membrane prepared in comparative example 2 was 210g/m 2 h, separation factor 5.83. In addition, the total flux of the strongly hydrophobic ZIF-8/polyether block composite membranes with different contents prepared in example 1 is increased along with the increase of the loading capacity, the separation factor is subjected to the process of first rising and then falling, and when the loading capacity is 10 wt%, the separation factor reaches the maximum value.
Claims (9)
1. A preparation method of a strong hydrophobic composite membrane is characterized by comprising the following steps:
(1) respectively dissolving 2-methylimidazole and zinc salt in absolute methanol to obtain a ligand solution and a zinc salt solution; then, quickly pouring the zinc salt solution into the ligand solution, reacting at room temperature, centrifuging, washing and drying to obtain ZIF-8;
(2) ultrasonically dispersing the obtained ZIF-8 in absolute methanol to obtain a uniform ZIF-8 dispersion liquid; dissolving imidazole derivatives in absolute methanol, dropwise adding a proper amount of triethylamine, and then quickly pouring the obtained ZIF-8 dispersion liquid into the anhydrous methanol to obtain a mixed solution; transferring to a polytetrafluoroethylene container, placing in an air-blast drying oven, fully reacting, centrifuging, washing and drying to obtain the strongly hydrophobic ZIF-8;
(3) dispersing the obtained strongly hydrophobic ZIF-8 in n-butanol to obtain a suspension, mixing and stirring the suspension and the polyether block amide solution for full reaction, and performing ultrasonic treatment and standing degassing to obtain a strongly hydrophobic ZIF-8/polyether block amide mixed solution;
(4) and casting the obtained ZIF-8/polyether block amide mixed solution with strong hydrophobicity to a polyether sulfone supporting layer, scraping the membrane, and drying to obtain the ZIF-8/polyether block amide composite membrane with strong hydrophobicity.
2. The method for preparing the strongly hydrophobic composite membrane according to the claim, wherein in the step (1), the molar ratio of the 2-methylimidazole to the zinc salt to the anhydrous methanol is 1 (7-9) to (600-800).
3. The method for preparing the strongly hydrophobic composite membrane according to the claim, wherein the molar ratio of ZIF-8, the imidazole derivative, the triethylamine and the absolute methanol in the step (2) is 1 (1.5-2.0) to (1.8-2.2) to (180-200).
4. The method for preparing the strongly hydrophobic composite membrane according to the claim, wherein the polyether block amide solution in the step (3) is prepared by the following method: dissolving polyether block amide in n-butyl alcohol, and fully stirring to obtain a polyether block amide solution with the weight of 5-8 wt%; the polyether block amide is PEBAX 2533.
5. The preparation method of the strongly hydrophobic composite membrane, according to the claim, wherein the mass ratio of the strongly hydrophobic ZIF-8 to the polyether block amide in the step (3) is 1: (7-39).
6. The method for preparing the strong hydrophobic composite membrane according to the claim, wherein the polyethersulfone supporting layer in the step (4) is prepared by the following method: dissolving the polyether sulfone in N, N-dimethylformamide, fully stirring to obtain a 15-20 wt% polyether sulfone solution, and casting to a non-woven fabric to obtain a polyether sulfone supporting layer.
7. The method for preparing the strongly hydrophobic composite membrane according to the claim, wherein the doping amount of the strongly hydrophobic ZIF-8 in the strongly hydrophobic ZIF-8/polyether block amide composite membrane obtained in the step (4) is less than or equal to 10 wt%.
8. The method for preparing the strongly hydrophobic composite membrane according to claim, wherein the zinc salt is zinc nitrate hexahydrate.
9. The method for preparing a highly hydrophobic composite membrane according to claim, wherein the imidazole derivative is 5, 6-dimethylbenzimidazole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210513073.5A CN114870637A (en) | 2022-05-11 | 2022-05-11 | Preparation method of strong hydrophobic composite membrane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210513073.5A CN114870637A (en) | 2022-05-11 | 2022-05-11 | Preparation method of strong hydrophobic composite membrane |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114870637A true CN114870637A (en) | 2022-08-09 |
Family
ID=82675889
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210513073.5A Pending CN114870637A (en) | 2022-05-11 | 2022-05-11 | Preparation method of strong hydrophobic composite membrane |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114870637A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20090033733A (en) * | 2007-10-01 | 2009-04-06 | 한국화학연구원 | A preparation of asymmetric porous peba membrane for composite membrane |
| US20120186446A1 (en) * | 2009-07-24 | 2012-07-26 | The Regents Of The University Of Colorado, A Body Corporate | Imidazolium-based room-temperature ionic liquids, polymers, monomers, and membranes incorporating same |
| CN103585899A (en) * | 2013-11-08 | 2014-02-19 | 江南大学 | Polyether copolyamide pervaporation membrane as well as preparation method and application thereof |
| CN103657458A (en) * | 2013-12-25 | 2014-03-26 | 大连欧科膜技术工程有限公司 | PEBA (Polyether block amide) composite film as well as preparation method and application thereof |
| KR20160026070A (en) * | 2014-08-29 | 2016-03-09 | 주식회사 앱스필 | Manufacturing method of gas separator membrane |
-
2022
- 2022-05-11 CN CN202210513073.5A patent/CN114870637A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20090033733A (en) * | 2007-10-01 | 2009-04-06 | 한국화학연구원 | A preparation of asymmetric porous peba membrane for composite membrane |
| US20120186446A1 (en) * | 2009-07-24 | 2012-07-26 | The Regents Of The University Of Colorado, A Body Corporate | Imidazolium-based room-temperature ionic liquids, polymers, monomers, and membranes incorporating same |
| CN103585899A (en) * | 2013-11-08 | 2014-02-19 | 江南大学 | Polyether copolyamide pervaporation membrane as well as preparation method and application thereof |
| CN103657458A (en) * | 2013-12-25 | 2014-03-26 | 大连欧科膜技术工程有限公司 | PEBA (Polyether block amide) composite film as well as preparation method and application thereof |
| KR20160026070A (en) * | 2014-08-29 | 2016-03-09 | 주식회사 앱스필 | Manufacturing method of gas separator membrane |
Non-Patent Citations (1)
| Title |
|---|
| XINLEI LIU 等: "Improvement of hydrothermal stability of zeolitic imidazolate frameworks", CHEM. COMMUN., vol. 49, no. 80, pages 9140 - 9142 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113209841B (en) | Mixed matrix membrane of aminated ZIF-8 and polyvinyl alcohol, and preparation method and application thereof | |
| CN110105580B (en) | Hierarchical pore zeolite imidazole ester framework material and preparation method thereof | |
| CN108097070B (en) | Zeolite imidazole ester doped polyether block amide gas separation membrane and preparation method and application thereof | |
| CN113346116A (en) | Polydopamine-modified hollow metal organic framework-modified polymer hybrid proton exchange membrane and preparation thereof | |
| CN106543461A (en) | MOF‑SO3H@GO modified polymer hybrid PEM and preparation method thereof | |
| CN110102184B (en) | Preparation method of PEG/ZIF-8/PVDF laminated assembled desulfurization membrane | |
| Lv et al. | Mixed matrix membranes comprising dual-facilitated bio-inspired filler for enhancing CO2 separation | |
| CN110523300B (en) | Method for preparing PEG/Cu-BTC/PVDF (polyethylene glycol/copper-BTC/polyvinylidene fluoride) desulfurization mixed matrix membrane by water-based process | |
| WO2023221564A1 (en) | Hydrophobic mof-based porous liquid carbon capture absorbent and preparation method therefor | |
| CN113713574B (en) | Preparation method of in-situ ring-opening reaction modified dual-function MOFs mixed matrix membrane | |
| CN108479434B (en) | Preparation method and application of Li-doped HKUST-1 membrane material | |
| CN110227456A (en) | MOFs derives two-dimensional multistage hole Cu/C composite material and preparation method | |
| CN106000119A (en) | Polyethylene glycol desulphurization composite film filled with active carbon and preparation method thereof | |
| CN112237852A (en) | Bionic material Bio-ZIF filled block polyether amide mixed matrix membrane and preparation method and application thereof | |
| CN114904404A (en) | Mixed matrix forward osmosis membrane based on MOF-808(Zr) and preparation method thereof | |
| CN103212314B (en) | Blended prior-alcohol-permeacomposite composite membrane of a kind of modified ZSM-5 zeolite and preparation method thereof | |
| CN113480741B (en) | Chelating Cu 2+ Preparation method of metal organic framework material and application of metal organic framework material in chitosan composite anion membrane | |
| CN105642130B (en) | Ionic Liquid Modified mesopore molecular sieve/composite membrane of polymer and its preparation and application | |
| CN111036089A (en) | Preparation method of modified PDMS/ZIF pervaporation hybrid membrane | |
| CN114870637A (en) | Preparation method of strong hydrophobic composite membrane | |
| CN116808848A (en) | Organic/inorganic MOF hybrid mixed matrix membrane with high separation performance, preparation method and application | |
| KR101467906B1 (en) | Method of manufacturing pervaporation using metal ion complex | |
| CN102716683B (en) | A kind of pervaporation hybrid membrane and uses thereof | |
| CN115350689A (en) | Preparation method of IL @ MOF composite material and application of IL @ MOF composite material in gas adsorption separation | |
| CN114225707A (en) | Hydrophobic modified hollow fiber membrane and preparation method and application thereof |
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 |