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CN-119241860-B - ZIF-8-based super-hydrophobic MOF, and preparation method and application thereof

CN119241860BCN 119241860 BCN119241860 BCN 119241860BCN-119241860-B

Abstract

The application relates to the technical field of metal organic framework functional materials, and discloses a ZIF-8-based superhydrophobic MOF, and a preparation method and application thereof. The ZIF-8-based superhydrophobic MOF is prepared by taking 2-methylimidazole and fluorine-containing ligand FL as mixed ligands, carrying out coordination reaction with Zn ions to obtain a ZIF-8-FL material, and carrying out grafting modification on the ZIF-8-FL material and a modifier under the action of an acid binding agent to obtain the ZIF-8-based superhydrophobic MOF, wherein the modifier is alkyl acyl chloride or fluorine-containing anhydride. The ZIF-8-based superhydrophobic MOF prepared by introducing the mixed ligand and grafting modification has the advantages of simple process, low cost and suitability for large-scale production, has high chemical stability and excellent hydrophobicity in an acidic environment, avoids the defect of easy degradation of conventional MOFs materials, has excellent separation efficiency and selectivity in the oil-water separation process, can effectively separate oil-water mixtures in various complex systems, and has wide market application prospect and economic benefit.

Inventors

  • HU WEI
  • XIA XINCHAO
  • YANG HUAI
  • YANG ZHOU
  • LIU JIALE
  • Yu Yinuo
  • XIAO YIXIAN

Assignees

  • 北京科技大学

Dates

Publication Date
20260508
Application Date
20241012

Claims (8)

  1. 1. The ZIF-8-based superhydrophobic MOF is characterized by being prepared by the following method: 2-methylimidazole and fluorine-containing ligand FL are used as mixed ligands, and a coordination reaction is carried out with Zn ions to obtain a ZIF-8-FL material; grafting and modifying the ZIF-8-FL material with a modifier under the action of an acid binding agent to obtain a ZIF-8-based superhydrophobic MOF; wherein the modifier is alkyl acyl chloride or fluorine-containing anhydride; the chemical structure of the fluorine-containing ligand FL is shown as a formula (1): (1) Wherein R 1 is 、 Or (b) R 2 is Or (b) N is an integer of 0 to 10; the acid binding agent is triethylamine or pyridine.
  2. 2. The ZIF-8-based superhydrophobic MOF of claim 1, The chemical structure of the alkyl acyl chloride is shown as a formula (2): (2) wherein x is an integer of 7 to 18; the chemical structure of the fluorine-containing anhydride is shown as a formula (3): (3) wherein y is an integer of 0 to 4.
  3. 3. The ZIF-8-based superhydrophobic MOF of claim 1, wherein the molar percentage of the fluorine-containing ligand FL in the mixed ligand is 5-20%.
  4. 4. The method for preparing the ZIF-8-based superhydrophobic MOF according to claim 1, comprising: S1, dispersing zinc nitrate hexahydrate, 2-methylimidazole and fluorine-containing ligand FL in a first organic solvent for coordination reaction, collecting a solid-phase product, washing and drying to obtain a ZIF-8-FL material; s2, dispersing the ZIF-8-FL material in a second organic solvent, and then adding an acid binding agent and a modifier to carry out grafting reaction under inert atmosphere to obtain the ZIF-8-based superhydrophobic MOF.
  5. 5. The method according to claim 4, wherein the first organic solvent is at least one of methanol or N, N-dimethylformamide; and/or the number of the groups of groups, The second solvent is at least one of dichloromethane, chloroform or tetrahydrofuran.
  6. 6. The preparation method according to claim 4, wherein the molar ratio of zinc nitrate hexahydrate to 2-methylimidazole is 1 (5-7); and/or the number of the groups of groups, The mass ratio of the ZIF-8-FL material to the modifier is 1 (1-36); and/or the number of the groups of groups, The mol ratio of the acid binding agent to the modifier is (1:1) - (1000:1).
  7. 7. The method according to claim 4, wherein the temperature of the coordination reaction is 20 to 70 ℃; the temperature of the grafting reaction is 20-40 ℃.
  8. 8. Use of the ZIF-8-based superhydrophobic MOF of any one of claims 1-3 or the ZIF-8-based superhydrophobic MOF prepared by the preparation method of any one of claims 4-7 in oil-water separation material.

Description

ZIF-8-based super-hydrophobic MOF, and preparation method and application thereof Technical Field The application relates to the technical field of metal organic framework functional materials, in particular to a ZIF-8-based superhydrophobic MOF, and a preparation method and application thereof. Background The oil-water separation technology has important significance in environmental protection and industrial production, and is particularly important in treating complex systems such as industrial wastewater, oilfield wastewater, ocean spilled oil and the like. At present, common oil-water separation materials for oil-water separation comprise membrane materials, adsorption materials, super-hydrophobic materials and the like. However, the conventional oil-water separation material has poor stability under acidic conditions and is easily corroded or degraded, thereby resulting in a decrease in separation efficiency. In addition, the preparation process of part of the oil-water separation material is complex and high in cost, and the popularization of the oil-water separation material in practical application is limited. Metal organic framework Materials (MOFs) have received attention in recent years due to their high specific surface area, adjustable pore size and good chemical stability. The ZIF-8 is a zinc-based MOF material, has a unique zeolite topological structure, has high structural stability, and has certain application potential in the field of oil-water separation. However, the stability of the existing ZIF-8 material in an acidic environment is still to be improved, and meanwhile, the hydrophobic performance of the material is further required to be enhanced so as to adapt to more complex oil-water separation conditions. Based on this, it is particularly necessary to develop a ZIF-8-based metal organic framework material having excellent stability and hydrophobic properties under acidic conditions. Disclosure of Invention The application provides a ZIF-8-based super-hydrophobic MOF, and a preparation method and application thereof, and aims to solve the problems of low stability and poor hydrophobic performance of the existing ZIF-8 material in an acidic environment. In order to achieve the above purpose, the present application is realized by the following technical scheme. In a first aspect of the application, there is provided a ZIF-8-based superhydrophobic MOF prepared by the method comprising: 2-methylimidazole and fluorine-containing ligand FL are used as mixed ligands, and a coordination reaction is carried out with Zn ions to obtain a ZIF-8-FL material; grafting and modifying the ZIF-8-FL material with a modifier under the action of an acid binding agent to obtain the modified ZIF-8-FL material; wherein the modifier is alkyl acyl chloride or fluorine-containing anhydride. Preferably, the fluorine-containing ligand FL has a chemical structure as shown in formula (1): wherein R 1 is R 2 is N is an integer of 0 to 10. Preferably, the chemical structure of the alkyl acyl chloride is shown as a formula (2): wherein x is an integer of 7 to 18; the chemical structure of the fluorine-containing anhydride is shown as a formula (3): wherein y is an integer of 0 to 4. Preferably, the acid binding agent is triethylamine or pyridine. Preferably, the molar percentage of the fluorine-containing ligand FL in the mixed ligand is 5-20%. In a second aspect of the present application, there is provided a preparation method of the above ZIF-8-based superhydrophobic MOF, comprising: s1, dispersing zinc nitrate hexahydrate, 2-methylimidazole and fluorine-containing ligand FL in a first organic solvent for coordination reaction, collecting a solid-phase product, washing and drying to obtain a ZIF-8-aFL material; s2, dispersing the ZIF-8-FL material in a second organic solvent, and then adding an acid binding agent and a modifier to carry out grafting reaction under inert atmosphere to obtain the ZIF-8-based superhydrophobic MOF. Preferably, the first organic solvent is at least one of methanol or N, N-dimethylformamide; and/or the number of the groups of groups, The second solvent is at least one of dichloromethane, chloroform or tetrahydrofuran. Preferably, the mol ratio of the zinc nitrate hexahydrate to the 2-methylimidazole is 1 (5-7); and/or the number of the groups of groups, The mass ratio of the ZIF-8-FL material to the modifier is 1 (1-36); and/or the number of the groups of groups, The mol ratio of the acid binding agent to the modifier is (1:1) - (1000:1). Preferably, the temperature of the coordination reaction is 20-70 ℃, and the temperature of the grafting reaction is 20-40 ℃. The application provides a ZIF-8-based superhydrophobic MOF or application of the ZIF-8-based superhydrophobic MOF prepared by the preparation method in an oil-water separation material. Compared with the prior art, the application has the beneficial effects that: The ZIF-8-based super-hydrophobic MOF is prepared by introduci