CN112808312B - Method for preparing nano metal-organic framework material catalytic membrane - Google Patents

Method for preparing nano metal-organic framework material catalytic membrane Download PDF

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CN112808312B
CN112808312B CN201911116143.8A CN201911116143A CN112808312B CN 112808312 B CN112808312 B CN 112808312B CN 201911116143 A CN201911116143 A CN 201911116143A CN 112808312 B CN112808312 B CN 112808312B
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membrane
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organic framework
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CN112808312A (en
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樊森清
王艺霖
仇博雅
肖泽仪
秦杨梅
王宇阳
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Sichuan University
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    • B01J31/181—Cyclic ligands, including e.g. non-condensed polycyclic ligands, comprising at least one complexing nitrogen atom as ring member, e.g. pyridine
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    • B01J2231/30—Addition reactions at carbon centres, i.e. to either C-C or C-X multiple bonds
    • B01J2231/34—Other additions, e.g. Monsanto-type carbonylations, addition to 1,2-C=X or 1,2-C-X triplebonds, additions to 1,4-C=C-C=X or 1,4-C=-C-X triple bonds with X, e.g. O, S, NH/N
    • B01J2231/341—1,2-additions, e.g. aldol or Knoevenagel condensations
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    • B01J2531/20—Complexes comprising metals of Group II (IIA or IIB) as the central metal
    • B01J2531/26—Zinc

Abstract

The invention discloses a method for preparing a nano metal-organic framework material catalytic membrane. Respectively percolating the precursor and the organic ligand through the porous base membrane, and preparing the nano metal-organic framework material catalytic membrane under the synergistic condition of flowing and reacting. The metal nano-particles or metal oxide nano-particles can also be synthesized in the pores of the membrane by a seepage method and the nano-metal-organic framework material is modified. The pore structure of the basement membrane is used as a synthesis reactor of metal-organic framework materials, metal or metal oxide nano particles. The nano metal-organic framework material catalytic membrane prepared by the synergy of the flow and the reaction in the membrane hole can effectively overcome the surface tension of liquid, so that the whole membrane hole can be filled with reaction liquid. The catalytic membrane prepared by the method has the advantages of good catalyst dispersibility, good stability, high loading capacity, high catalytic efficiency and the like.

Description

Method for preparing nano metal-organic framework material catalytic membrane
Technical Field
The invention relates to a method for preparing a nano metal-organic framework material catalytic membrane, in particular to a nano metal-organic framework material catalytic membrane which is assembled by the cooperation of flowing and reaction in membrane pores.
Background
The metal-organic framework material and the composite material thereof have large specific surface area, large porosity, regular cage structure and adjustable structure, so that the metal-organic framework material and the composite material thereof have large application potential in the field of catalysis [1,2 ]. If the metal-organic framework material is prepared into the nano-scale powder material, the catalytic effect of the nano-scale powder material is obviously enhanced due to small size, large specific surface area and more surface active sites. However, the powder material is difficult to recover, which would prevent the metal-organic framework material from being practically used. In addition, the nano powder metal-organic framework material is easy to agglomerate due to large surface energy, and the catalytic performance of the metal-organic framework material is also influenced. From the reactor point of view, the immobilization and dispersion of the metal-organic framework material is critical in determining its successful application. The porous membrane support has uniformly distributed pores with uniform pore diameters. If the nano metal-organic framework catalyst is immobilized in the pore canal of the membrane support, the immobilization and dispersion of the nano metal-organic framework material can be well realized. In addition, the metal-organic framework material is arranged in the pore channel of the membrane support body, so that the catalytic reaction is carried out in the membrane pore with the micro-nano scale, the concentration polarization can be reduced, and the catalytic reaction efficiency is improved.
The catalyst is immobilized on the surface of the membrane substrate, so that the mass transfer efficiency in the catalysis process can be improved, and the catalyst is a main structure of the current catalytic membrane. To increase the stability of the catalyst to the membrane substrate, the membrane substrate is often functionally modified and then bonded to the catalyst [3 ]. In addition, the stability of the catalyst and the membrane substrate can also be improved by depositing a layer of dopamine with adhesion on the membrane substrate and then loading the catalyst [4 ]. Due to the rigid character of the metal-organic framework material, there is still a greater risk of stabilization when the membrane substrate surface is loaded with more metal-organic framework material. In addition, the problem of agglomeration of the nanocatalyst is difficult to solve by the surface immobilization of the membrane. In order to disperse and fix the catalyst inside the membrane pores, the catalyst is blended with the membrane casting solution by Sharpe and the like, and the catalyst is migrated to the surface of the membrane pores by utilizing the surface migration effect in the membrane forming process [5 ]. The method can well improve the solid-carrying stability of the catalyst. When the amount of the catalyst to be immobilized is large, a certain proportion of the catalyst is embedded in the membrane and cannot migrate to the surface of the membrane pores, so that the utilization efficiency of the catalyst is reduced.
In order to further improve the dispersibility and stability of the nano-catalyst, the base film can be soaked in a precursor solution of the metal-organic framework material, so that the precursor solution is filled in the film hole and reacts and crystallizes in the film hole, and thus the metal-organic framework material is loaded in the film hole. The method realizes the purpose of in-situ synthesis of the loaded nano-catalyst in the membrane pores, and can well control the size of the nano-catalyst. Due to the action of the surface tension of the liquid, the speed of the liquid entering the membrane pores is slow, and after a certain amount of metal-organic framework materials are generated in the membrane pores, the liquid is difficult to infiltrate into the membrane pores. Based on the background, the metal-organic framework precursor is infiltrated in the base film, and the nano metal-organic framework material is synthesized in situ in the hole, so that the nano metal-organic framework material catalytic film is constructed.
Disclosure of Invention
The invention provides a method for directly synthesizing and assembling a nano metal-organic framework material catalytic membrane inside a base membrane in a seepage way in order to improve the stability of a metal-organic framework material with catalytic activity and a composite material thereof and improve the catalytic performance of the metal-organic framework material and the composite material thereof, and the nano metal-organic framework material is synthesized by utilizing the microporous structure of the base membrane and assembled into the metal-organic framework material composite membrane.
The invention adopts the main technical scheme that: a method for assembling a nano metal-organic framework material catalytic membrane by seepage synthesis is characterized by comprising the following main steps.
(1) Introducing a precursor into the inner pore channel of the porous base membrane: and (3) infiltrating the precursor with a certain concentration through the porous base membrane, and taking out the membrane for drying after the infiltration is finished.
(2) Introducing an organic ligand into the inner pore channel of the porous base membrane: and (3) percolating an organic ligand solution with a certain concentration through the membrane in the step (1), and drying after the percolation is finished to prepare the nano metal-organic framework material catalytic membrane assembled by percolation synthesis.
(3) In order to prepare the catalytic membrane with more catalytic functions, the nano metal-organic framework material catalytic membrane prepared in the step (2) can be modified by introducing metal nano particles or metal oxide nano particles with catalytic action through seepage.
The specific process of introducing the metal nanoparticles or metal oxide nanoparticles with catalytic action by seepage comprises the following steps: introducing metal ions into the nano metal-organic framework material catalytic membrane from a metal salt solution with a certain concentration by adopting a seepage method, and drying to obtain a nano metal-organic framework material catalytic membrane modified by metal oxide nano particles; then, a reducing agent solution with a certain concentration is permeated and flowed in the membrane to reduce the metal oxide into a metal simple substance, and the nano metal-organic framework material catalytic membrane modified by the metal nano particles can be prepared after drying.
The concentration of the precursor and the organic ligand and the type of the solvent used for synthesizing the metal-organic framework material can be selected by referring to the published traditional synthesis method of the metal-organic framework material; the concentrations of the metal salt solution and the reducing agent solution used for synthesizing the metal nanoparticles or metal oxide nanoparticles may be selected with reference to a conventional synthesis method of the metal or metal oxide, and the forms of the precursor and the organic ligand may be selected to be gaseous or liquid according to reaction characteristics.
In the fluid seepage process, the flow rate of the fluid can be controlled by controlling the driving force on two sides of the membrane: when the flow rate of the fluid is too high, the pushing force is reduced to prevent the fluid from staying for too short time; increasing the pushing force when the fluid flow rate is too slow prevents the fluid from failing to seep due to too much resistance.
In the preparation process of the catalytic film, the loading capacity of the metal-organic framework material in the catalytic film can be controlled by controlling the seepage times of the precursor and the organic ligand; the loading of metal nanoparticles and metal oxide nanoparticles in the catalytic membrane of the nano metal-organic framework material is controlled by controlling the seepage times of the metal salt solution and the reducing agent solution.
Compared with the prior art, the research has the following advantages.
(1) The catalyst has better dispersibility: the metal-organic framework material is assembled in the porous base membrane through seepage synthesis and is modified by the metal nano particles or the metal oxide nano particles, so that the pore space of the porous base membrane is fully utilized to disperse the metal-organic framework material, the metal nano particles or the metal oxide nano particles, the contact area of a catalyst and a reactant is greatly increased, and the catalytic activity is favorably improved.
(2) The catalyst has better stability and is convenient to recycle and operate: the metal-organic framework material, the metal nanoparticles and the metal oxide nanoparticles are directly assembled in the pores of the porous base membrane through seepage synthesis, so that the powdery nano material is formed into a membrane, the stability of the catalyst is improved, the recovery operation with high energy consumption and complicated process is avoided, the loss of the catalyst in the reaction process is reduced, and the industrial production cost is reduced.
(3) The loading of the catalyst is controllable: the pores of the porous base membrane provide enough loading space for the catalyst, and the loading capacity of the catalyst in the catalytic membrane can be regulated and controlled by controlling the seepage frequency of the solution in the assembling process of the catalytic membrane, so that the catalytic membrane with different catalyst loading capacity, wider application range, higher assembling flexibility and higher controllability is obtained by assembling.
(4) The microporous structure of the porous base membrane provides a natural micro-reaction channel for the metal-organic framework material, the metal nanoparticles and the metal oxide nanoparticles, and can be used as a membrane hole micro-reactor.
Drawings
FIG. 1 is a schematic illustration of a liquid phase fluid percolation process in accordance with the present invention.
FIG. 2 is a schematic view of the process of gas phase fluid percolation in the present invention.
FIG. 3 is an SEM cross-sectional representation of a ZIF-8/PES catalytic membrane prepared in example 1 of the invention.
FIG. 4 is a SEM cross-sectional representation of a Cu @ ZIF-8/PES catalytic membrane prepared in example 2 of the invention.
Detailed Description
The present invention will be described in detail below with reference to specific examples, but the present invention is not limited to the following examples, and various modifications and implementations are included within the technical scope of the present invention without departing from the content and scope of the present invention.
Example 1: ZIF-8/PES catalytic membrane was used for Knoevenagel reaction of benzaldehyde.
In the embodiment, a polyether sulfone (PES) membrane with the pore diameter of 0.45 mu m is selected as a catalytic membrane base membrane, a target metal-organic framework material is a zeolite imidazole framework ZIF-8 with catalytic activity, and a precursor and an organic ligand are both liquid phases. In order to test the catalytic performance of the catalytic membrane, Knoevenagel condensation reaction of benzaldehyde and ethyl isocyanoacetate is selected as a catalytic system. The specific implementation steps are as follows.
(1) Firstly, introducing Zn into PES basal membrane by percolation method2+The specific implementation process is as follows: weighing Polyethersulfone (PES) raw membrane, placing on a positive pressure filter disc with filter paper, then compacting the positive pressure filter, and pouring 50mL of Zn (NO) with the concentration of 0.54mol/L3)2The driving force of the precursor solution is the pressure difference between the two sides of the membrane, the precursor solution is realized by introducing inert gas into the filter, and the flow rate of the solution passing through the filter is controlled by controlling the pressure of the inert gas; and after about 20min of filtration, sequentially taking out the membranes, drying in an electrothermal constant-temperature drying oven at 60 ℃ for 30min, and weighing.
(2) Then introducing a 2-methylimidazole organic ligand into the membrane pores, and specifically comprising the following steps: placing the dried membrane in the step (1) on a positive pressure filter disc with filter paper, then pressing the positive pressure filter tightly, pouring 50mL of 2-methylimidazole solution with the concentration of 0.95mol/L, and controlling the flow rate of the solution passing through the filter by controlling the pressure of inert gas; after about 20min of filtration, the membrane was taken out, dried in an electrothermal constant temperature drying oven at 60 ℃ for 30min and weighed.
(3) Repeating the steps (1) and (2) twice, and passing Zn (NO) for 3 times in total3)2And soaking the solution and the 2-methylimidazole solution for 3 times in water for 12 hours, washing off impurities and dust on the surface of the membrane, and drying at the constant temperature of 60 ℃ for 24 hours to obtain the ZIF-8/PES catalytic membrane.
(4) The specific implementation steps of the ZIF-8/PES catalytic membrane catalytic experiment are as follows: a mixture of 50mL of a 0.1mol/L benzaldehyde solution and 50mL of a 0.1mol/L ethyl isocyanoacetate solution was prepared as a reaction solution. Sucking the reaction solution into a medical injector, pushing the reaction solution in the injector to flow through a membrane component provided with a catalytic membrane at a constant speed by using an injection pump, and collecting the solution passing through the membrane at the downstream by using a beaker. The collected downstream solutions were tested for reactant and reaction product concentrations using a gas chromatograph.
The catalytic experiment result shows that the conversion rate of benzaldehyde can reach 95-100% after normal temperature catalysis by the ZIF-8/PES catalytic membrane, the yield of the target product is more than 99%, and the catalytic membrane can obviously improve the reaction progress degree of benzaldehyde and ethyl cyanoacetate.
Example 2: the Cu @ ZIF-8/PES catalytic membrane degrades nitrophenol.
In the embodiment, a polyether sulfone (PES) membrane with the aperture of 0.45 mu m is selected as a catalytic membrane base membrane, a target metal-organic framework material is ZIF-8 with a zeolite imidazole framework, a precursor is a liquid phase, and an organic ligand is a gas phase. The main catalyst with catalytic action in the catalytic membrane is metal Cu nano-particles. In order to test the catalytic performance of the catalytic membrane, a strong reducing agent NaBH is selected4The decomposition reaction of p-nitrophenol (4-NP) is used as a catalytic system. The specific implementation steps are as follows.
(1) Firstly, introducing ZnO nano-rods by a percolation method. The specific implementation process comprises the following steps: weighing a Polyethersulfone (PES) original membrane, placing the membrane on a positive pressure filter disc with filter paper, then compacting the positive pressure filter, pouring 100mL of 70mmol/L zinc acetate solution (the solvent is absolute ethyl alcohol), taking out the membrane after filtering is completed for about 40min, and placing the membrane in an electric heating constant temperature drying oven for drying at 60 ℃ for 60min and then weighing; then 100mL of NaOH solution (solvent is absolute ethyl alcohol) with the concentration of 0.1mmol/L is poured into the positive pressure filter by the same method; repeating the operation twice, wherein the film passes through a zinc acetate solution and a NaOH solution for 3 times in total, then is soaked in water for 12 hours, impurities and dust on the surface of the film are washed away, and the film is dried at a constant temperature of 60 ℃ for 24 hours; the dried membrane was taken out, placed in a positive pressure filter, and 500mL of a 50mmol/L zinc acetate solution and 500mL of a 50mmol/L hexamethylenetetramine solution were poured therein, subjected to hydrothermal reaction at 90 ℃ for 18 hours, and finally dried at 60 ℃.
(2) The gas phase organic ligand is then introduced by percolation. The specific implementation process comprises the following steps: and (2) taking out the dried membrane in the step (1), placing the membrane on a positive pressure filter disc, weighing 50g of 2-methylimidazole, completely filling the 2-methylimidazole in a cavity of the positive pressure filter disc, converting the 2-methylimidazole into a gas phase at 125 ℃, percolating the gas from bottom to top through a composite membrane with ZnO nanorods attached inside, treating the gas phase for 24 hours, and drying the membrane at 60 ℃ to obtain the ZIF-8/PES membrane.
(3) And finally, modifying the ZIF-8/PES composite membrane by using Cu nanoparticles with catalytic activity to prepare the Cu @ ZIF-8/PES catalytic membrane. The specific implementation process comprises the following steps: firstly, 50mL of Cu (NO) with a concentration of 0.15mol/L3)2Pouring the solution into a positive pressure filter filled with a ZIF-8/PES membrane, controlling the pressure of the introduced inert gas to control the slow flow of the solution at a low speed, taking out the membrane after about 20min, and drying at 60 ℃ for 1h to change the membrane from colorless to blue. Then weighing the dried membrane, placing the membrane on a filter disc for compacting, and pouring 50mL of freshly prepared 1mol/LNaBH into the positive pressure filter4Solution, NaBH4As a strong reducing agent, Cu may be used2+Reducing the solution into a catalyst simple substance Cu, controlling the pressure of the introduced inert gas to control the solution to slowly flow out at a low speed, taking out the membrane after about 20min, drying the membrane at the temperature of 60 ℃ for 1h, and changing the blue color of the membrane into brownish black to obtain the Cu @ ZIF-8/PES catalytic membrane.
(4) The specific implementation steps for testing the catalytic performance of the Cu @ ZIF-8/PES catalytic membrane are as follows: 10mL of 0.17mol/L NaBH was mixed with 20mL of 0.27 mmol/L4-NP solution4Solution, adding NaBH4Changing the 4-NP solution from light yellow to bright yellow after the solution is dissolved, uniformly stirring to obtain a reaction solution, sucking the reaction solution into a medical injector, pushing the reaction solution in the injector to flow through a membrane component provided with a catalytic membrane at a constant speed by using an injection pump, and collecting the solution passing through the membrane at the downstream by using a beaker. The spectrophotometry at 400nm wavelength (reactant) and 300nm wavelength (reaction product) of the initial solution and the downstream solution was measured with a spectrophotometer, and the standard solution was deionized water.
The above Experimental Process NaBH4The solution is ready to use after being prepared and is operated in a fume hood to prevent NaBH4H produced by reaction with water2Gather in the small space, guarantee the experiment safety.
The catalytic experiment result shows that after being catalyzed by a Cu @ ZIF-8/PES catalytic membrane, the 400nm spectral content of the reaction solution is obviously reduced, the 300nm spectral content is obviously improved, the 4-NP conversion rate is more than 99 percent, and 4The NP decomposition reaction is carried out more thoroughly under the catalysis of a catalytic membrane; the highest reaction rate of the injection method 4-NP decomposition reaction can reach 267mmol L-1min-1The reaction rate constant can reach 878min at most-1The catalytic membrane can obviously improve the decomposition rate of 4-NP.
When the cumulative continuous service time of the Cu @ ZIF-8/PES catalytic membrane reaches 5h, the conversion rate of 4-NP is still maintained to be more than 95%, and the catalytic membrane shows good stability.
Example 3: MnO2@ ZIF-8/PES catalytic membrane degrades formaldehyde.
In the embodiment, a polyether sulfone (PES) membrane with the aperture of 0.45 mu m is selected as a catalytic membrane base membrane, a target metal-organic framework material is ZIF-8 with a zeolite imidazole framework, and a precursor and an organic ligand are both liquid phases. The main catalyst with catalytic action in the catalytic membrane is metal oxide MnO2And (3) nanoparticles. In order to test the catalytic performance of the catalytic membrane, the decomposition reaction of formaldehyde is selected as a catalytic system. The specific implementation steps are as follows.
(1) Firstly, preparing a ZIF-8/PES composite membrane by a seepage method. The specific implementation process comprises the following steps: weighing Polyethersulfone (PES) raw membrane, placing on a positive pressure filter disc with filter paper, then compacting the positive pressure filter, and pouring 50mL of Zn (NO) with the concentration of 0.54mol/L3)2The solution, the flow rate of the solution passing through the filter is controlled by controlling the pressure of the inert gas; after about 20min of filtration, taking out the membrane, drying in an electrothermal constant-temperature drying oven at 60 ℃ for 30min, and weighing; then 50mL of 2-methylimidazole solution with the concentration of 0.95mol/L is poured into the positive pressure filter by adopting the same method; the above operation was repeated twice, and the film was passed 3 times of Zn (NO) in total3)2And soaking the solution and the 2-methylimidazole solution for 3 times in water for 12 hours, washing off impurities and dust on the surface of the membrane, and drying at the constant temperature of 60 ℃ for 24 hours to obtain the ZIF-8/PES composite membrane.
(2) Then with MnO having catalytic activity2The ZIF-8/PES composite membrane is modified by metal oxide nano particles, and MnO is obtained through preparation2@ ZIF-8/PES catalytic membrane. The specific implementation process comprises the following steps: firstly, 50mL of 0.4mol/L MnSO4Pouring the solution into a positive pressure filter equipped with ZIF-8/PES membrane, and controlling the flowThe solution slowly flows out at a low speed under the pressure control of the inert gas, the membrane is taken out after about 20min, and the membrane is dried for 1h at the temperature of 60 ℃. Then the dried membrane is weighed, placed on a filter disc to be compressed, and 50mL of 0.1mol/L KMnO is poured into the positive pressure filter4Controlling the pressure of the introduced inert gas to control the slow outflow of the solution at a low speed, taking out the membrane after about 20min, and drying at 60 ℃ for 1h to obtain MnO2@ ZIF-8/PES catalytic membrane.
(3)MnO2The specific implementation steps of the test of the catalytic performance of the @ ZIF-8/PES catalytic membrane are as follows: injecting 30mL of 74mg/L liquid formaldehyde into a syringe, and making the initial solution pass through a syringe filled with MnO under the drive of a medical injection pump2The membrane component of the @ ZIF-8/PES catalytic membrane can be used for measuring the spectrophotometry of a downstream solution, the degradation rate of formaldehyde can be calculated, and the injection speed can be adjusted by a medical injection pump.
(4) The results of catalytic experiments show that the catalyst is subjected to MnO2After the @ ZIF-8/PES catalytic membrane is degraded at 85 ℃, the concentration of formaldehyde is reduced from 74mg/L to 0.22mg/L, the degradation rate reaches more than 99%, and good catalytic activity is shown.
Reference to the literature
[1]L.Jiao,Y.Wang,H.L.Jiang,Q.Xu,Metal-Organic Frameworks as Platforms for Catalytic Applications,Adv.Mater.,30(2018)e1703663.
[2]J.Lee,O.K.Farha,J.Roberts,K.A.Scheidt,S.T.Nguyen,J.T.Hupp,Metal-organic framework materials as catalysts,Chem.Soc.Rev.,38(2009)1450-1459.
[3]R.Chen,Y.Jiang,W.Xing,W.Jin,Fabrication and Catalytic Properties of Palladium Nanoparticles Deposited on a Silanized Asymmetric Ceramic Support,Ind.Eng.Chem.Res.,50(2011)4405-4411.
[4]N.Li,G.Chen,J.Zhao,B.Yan,Z.Cheng,L.Meng,V.Chen,Self-cleaning PDA/ZIF-67@PP membrane for dye wastewater remediation with peroxymonosulfate and visible light activation,J.Membrane Sci.,591(2019)117341.
[5]R.Xie,F.Luo,L.Zhang,S.F.Guo,Z.Liu,X.J.Ju,W.Wang,L.Y.Chu,A Novel Thermoresponsive Catalytic Membrane with Multiscale Pores Prepared via Vapor-Induced Phase Separation,Small,14(2018)e1703650.

Claims (10)

1. A method for preparing a catalytic membrane of a nano metal-organic framework material is characterized in that the preparation of the catalytic membrane comprises the following steps:
(1) loading a metal precursor in a pore channel in the porous base membrane, percolating the precursor with a certain concentration from one side of the membrane to the other side of the membrane by adopting a percolation method, and taking out the membrane for drying after the percolation is finished;
(2) introducing an organic ligand into the pore channel inside the porous base membrane, and assembling and synthesizing the nano metal-organic framework material membrane: infiltrating an organic ligand with a certain concentration from one side of the membrane to the other side of the membrane loaded with the metal precursor by adopting a percolation method, and synthesizing the metal precursor and the organic ligand into a metal organic-framework material in a membrane hole;
(3) in order to prepare the catalytic membrane with more catalytic functions, the nano MOFs catalytic membrane prepared in the step (2) can be modified by introducing metal nanoparticles or metal oxide nanoparticles with catalytic action through seepage.
2. The method for preparing a catalytic membrane of nanometal-organic framework materials according to claim 1, wherein the concentration of the precursor and the organic ligand is characterized in that the concentration of the precursor and the concentration of the organic ligand and the type of the solvent are selected with reference to the concentration of the solution and the type of the solvent in the conventional MOFs preparation method, and the prepared MOFs include, but are not limited to IRMOF series materials, MIL series materials, ZIF series materials and UiO series materials; and the forms of the precursor and the organic ligand can be selected to be gas phase or liquid phase according to the reaction characteristics.
3. The method for preparing the catalytic membrane with the nano metal-organic framework material according to claim 1, wherein the size of the prepared MOFs can be adjusted and controlled according to the pore size of the selected porous base membrane, and the porous base membrane comprises but is not limited to Polyethersulfone (PES), Polytetrafluoroethylene (PTFE), Polyamide (PA) and ceramic membranes.
4. The method for preparing a catalytic film of nanometal-organic framework material according to claim 1, wherein said percolation introducing the precursor and the organic ligand is characterized in that the amount of the MOFs immobilized in the catalytic film can be controlled by controlling the number of times the precursor and the organic ligand percolates.
5. The method for preparing a catalytic membrane of nanometal-organic framework material according to claim 1, said percolation introducing precursor and organic ligand being characterized by controlling the percolation rate of the fluid by controlling the amount of pushing force on both sides of the base membrane: when the fluid flow rate is too fast, the driving force is reduced to prevent the fluid from staying for too short time to lead precursor ions or organic ligands not to be introduced into the film; increasing the pushing force when the fluid flow rate is too slow prevents the fluid from failing to seep due to too much resistance of the basement membrane.
6. The method for preparing a catalytic membrane of nanometal-organic framework material according to claim 5, wherein the driving force on both sides of the basement membrane includes, but is not limited to, pressure difference, concentration difference and electric field on both sides of the basement membrane.
7. The method for preparing the catalytic membrane of the nano-metal-organic framework material according to claim 1, wherein the step of introducing metal nanoparticles or metal oxide nanoparticles having catalytic action into the nano-MOFs catalytic membrane by percolation is characterized in that metal ions can be introduced into the nano-MOFs catalytic membrane by a metal salt solution with a certain concentration by adopting a percolation method, and the nano-MOFs catalytic membrane modified by the metal oxide nanoparticles is prepared after drying; then, a reducing agent solution with a certain concentration is introduced into the seepage flow to reduce the metal oxide into a metal simple substance, and the metal simple substance is dried to prepare the nano MOFs catalytic film modified by the metal nano particles.
8. The method for preparing a catalytic membrane of nanometal-organic framework material according to claim 7 wherein the concentration of the metal salt solution and the reducing agent solution is selected with reference to the concentration of the metal salt solution and the concentration of the solution in conventional methods for preparing metal particles or metal oxide particles, including but not limited to Au、Ag、Cu、Fe、Zn、Mn、CuO、ZnO、MnO2，TiO2And the solid loading of the metal nanoparticles and the metal oxide nanoparticles in the nano MOFs catalytic film can be controlled by controlling the seepage times of the metal salt solution and the reducing agent solution.
9. The method for preparing a catalytic membrane of nanometal-organic framework material according to claim 7, said percolation induced metal nanoparticles and metal oxide nanoparticles being characterized by controlling the flow rate of the solution by controlling the amount of pushing force on both sides of the membrane: when the solution flow rate is too high, the driving force is reduced to prevent the solution from staying for too short to cause no metal ions to be introduced into the membrane or insufficient reduction; when the flow rate of the solution is too slow, the pushing force is increased to prevent the solution from being incapable of seepage due to too large resistance of the basement membrane.
10. The method for preparing a nanometal-organic framework catalytic membrane according to claim 9, wherein the driving force across the membrane includes, but is not limited to, pressure difference, concentration difference, and electric field across the membrane.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106397797A (en) * 2016-08-29 2017-02-15 山东师范大学 Gold-MOFs-polymer composite membrane, and production method and application thereof
CN109395780A (en) * 2018-09-29 2019-03-01 浙江工业大学 A kind of gold nano grain-metal organic framework ceramic catalytic film and the preparation method and application thereof
CN109701468A (en) * 2019-01-24 2019-05-03 四川大学 The percdation of composite function nano material-synthesis building method

Family Cites Families (2)

* Cited by examiner, † Cited by third party
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WO2014115177A2 (en) * 2013-01-28 2014-07-31 Council Of Scientific & Industrial Research A process for the preparation of mofs-porous polymeric membrane composites
US10188981B2 (en) * 2017-04-21 2019-01-29 King Fahd University Of Petroleum And Minerals Mixed matrix membrane, a method of making thereof, and a method for gas separation

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106397797A (en) * 2016-08-29 2017-02-15 山东师范大学 Gold-MOFs-polymer composite membrane, and production method and application thereof
CN109395780A (en) * 2018-09-29 2019-03-01 浙江工业大学 A kind of gold nano grain-metal organic framework ceramic catalytic film and the preparation method and application thereof
CN109701468A (en) * 2019-01-24 2019-05-03 四川大学 The percdation of composite function nano material-synthesis building method

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