A three-dimensional MOF material, its preparation method and application

Abstract

This invention discloses a three-dimensional MOF material, its preparation method, and its applications, belonging to the field of organic synthesis technology. This invention uses an organic monomer with structural formula (I) as a ligand and zinc, cobalt, or copper salts as metal salts to prepare Zn-MOF, Co-MOF, or Cu-MOF metal-organic framework materials via a solvothermal method. This invention optimizes the material's performance by adjusting the types of ligands and metal ions, making it more suitable for treating specific types of organic pollutants. Furthermore, this invention is the first to synthesize three MOF materials based on a novel pyrazole organic monomer with a novel chemical structure. The three-dimensional MOF material, with its unique electronic structure, promotes the formation of catalytic active centers, accelerates the redox reaction of pollutants, and achieves efficient degradation. Moreover, the synthesized three-dimensional MOF material can provide abundant active sites, promoting the adsorption and activation of pollutant molecules.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, specifically relating to a three-dimensional MOF material, its preparation method, and its application. Background Technology

[0002] With the advancement of science and technology and social development, environmental pollution problems are becoming increasingly severe, especially the emission of organic pollutants, which poses a serious threat to human health and the ecological environment. Traditional methods for treating organic pollutants, such as incineration and chemical oxidation, are not only energy-intensive and costly, but may also generate secondary pollution. In recent years, metal-organic frameworks (MOFs) have become a highly promising adsorbent and catalyst material due to their unique porous structure, high specific surface area, good chemical stability, and tunability, and are widely used in gas adsorption, separation, catalytic reactions, and other fields.

[0003] Currently, the removal of organic pollutants mainly relies on methods such as physical adsorption and chemical degradation. However, while traditional physical adsorbents such as activated carbon can effectively adsorb pollutants, they are not very effective for some small molecule pollutants that are difficult to adsorb. Although chemical degradation methods can completely decompose pollutants, they often require harsh reaction conditions and may produce toxic byproducts.

[0004] Existing technologies for adsorbing and degrading pollutants have several shortcomings: On the one hand, traditional adsorbent materials often exhibit poor selectivity for specific pollutants, easily adsorbing multiple substances simultaneously, leading to complex subsequent separation and treatment processes; on the other hand, these materials have limited adsorption capacity, failing to effectively handle high concentrations of pollutants, and their regeneration processes are complex and costly, resulting in resource waste and increased treatment costs. Furthermore, under certain extreme conditions, such as high temperature, high pressure, or strong acid / alkali environments, the stability and adsorption efficiency of adsorbents significantly decrease. Regarding degradation technologies, traditional methods have low degradation efficiency for certain stubborn pollutants (such as persistent organic pollutants) and often require specific environmental conditions to function, increasing operational difficulty and cost. Simultaneously, toxic byproducts may be generated during degradation, causing secondary pollution to the environment, and some degradation technologies have narrow application ranges, making them difficult to effectively treat mixed pollutants. Summary of the Invention

[0005] To address the shortcomings of the prior art, this invention provides a three-dimensional MOF material, its preparation method, and its application.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A three-dimensional MOF material, using an organic monomer with the structural formula (Ⅰ) as a ligand and zinc salt, cobalt salt or copper salt as a metal salt, is prepared by a solvothermal method to obtain a Zn-MOF metal-organic framework material, a Co-MOF metal-organic framework material or a Cu-MOF metal-organic framework material;

[0008] The structural formula of the organic monomer is as follows:

[0009]

[0010] As a preferred embodiment of the present invention, the method for preparing the organic monomer with the structural formula (Ⅰ) includes the following steps:

[0011] (1) Tetra(4-bromophenyl)ethylene, 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxoron-2-yl)-1H-pyrazole, tetrabutylammonium bromide and tetra(triphenylphosphine)palladium are added to organic solvent A under an inert gas atmosphere, and alkaline solution B is added and stirred or sonicated to obtain a mixed solution;

[0012] (2) Then, after heating and refluxing in an inert gas atmosphere and cooling to room temperature, after rotary evaporation, extraction and rotary evaporation, alcohol and acid A are added and sonicated, and then stirred until the acidification reaction is completed to obtain a suspension.

[0013] (3) After adjusting the pH to 7 by pouring the suspension into water, a precipitate was obtained. The precipitate was washed and dried to obtain an organic monomer with the structural formula (Ⅰ).

[0014] As a preferred embodiment of the present invention, the molar ratio of tetra(4-bromophenyl)ethylene and 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxoborane-2-yl)-1H-pyrazole is 1:(5-8); the mass ratio of tetrabutylammonium bromide and tetra(triphenylphosphine)palladium is (0.2-1.0)g:(0.08-0.25)g; and the mass ratio of tetra(4-bromophenyl)ethylene and tetrabutylammonium bromide is (1.8-2.5):(0.8-1).

[0015] In a preferred embodiment of the present invention, the organic solvent A is xylene or toluene; the alkaline solution B is an aqueous solution of potassium carbonate, the volume ratio of the alkaline solution B does not exceed 10% of the total volume of the mixed solution, and the mass concentration of potassium carbonate in the aqueous solution of potassium carbonate is 0.4 g / mL-0.8 g / mL.

[0016] In a preferred embodiment of the present invention, the alcohol is methanol or ethanol, and acid A is nitric acid, hydrochloric acid, or sulfuric acid; the acidification reaction time is 4-8 hours; the extractant used for extraction is a mixture of solvent and water, the solvent is dichloromethane or dichloroethane, and the volume ratio of solvent to water is 1:(0.5-1); the reflux temperature is 100-135°C, the time is 24-72 hours, and the reflux method is an oil bath or a sand bath.

[0017] In a preferred embodiment of the present invention, in step (3), the volume ratio of the suspension to water is 1:(5-10), and more preferably, the volume ratio of the suspension to water is 1:(8-10).

[0018] A method for preparing a three-dimensional MOF material includes the following steps: dissolving an organic monomer with the structural formula (Ⅰ) in an organic solvent B to obtain a mixed solution, then adding an organic solvent C and a metal salt and heating to react to obtain Zn-MOF, Co-MOF or Cu-MOF; the metal salt is a zinc salt, a cobalt salt or a copper salt.

[0019] In a preferred embodiment of the present invention, when preparing Zn-MOF, the organic solvent C is a mixed solution of methanol, dimethyl sulfoxide, acid B, and acid C in a volume ratio of 1:0.3-0.5:0.07-0.1:0.005-0.05; when preparing Co-MOF, the organic solvent C is a mixed solution of methanol, water, dimethyl sulfoxide, acid B, and acid C in a volume ratio of 1:0.1-0.3:0.3-0.5:0.07-0.1:0.005-0.05; when preparing Cu-MOF, the organic solvent C... The mixture is a solution of ethanol, dimethyl sulfoxide, acid B, and acid C in a volume ratio of 1:0.1-0.3:0.07-0.1:0.005-0.05; the organic solvent B is dimethyl sulfoxide, N,N-dimethylformamide, or N,N-dimethylacetamide; acid B is glacial acetic acid; acid C is a 10% sulfuric acid solution; the mass concentration of the organic monomer with structural formula (Ⅰ) in the mixture is 1-10 mg / mL; the amount of zinc salt, cobalt salt, or copper salt is 0.01-0.02 g / mL, and the volume is 0.1-0.2 mL.

[0020] In a preferred embodiment of the present invention, the heating reaction temperature is 100-130°C, the time is 12-56 hours, the heating rate is 10-20°C / hour, and the cooling rate is 5-10°C / hour; more preferably, the heating reaction temperature is 105-120°C.

[0021] The present invention also claims protection for the use of the three-dimensional MOF material in the removal of organic pollutants or in the activation of PMS to remove organic pollutants from water.

[0022] More preferably, the application of the Co-MOF material in the removal of organic pollutants.

[0023] More preferably, the three-dimensional MOF material is used in activating PMS to remove organic pollutants from water.

[0024] Compared with existing technologies, the beneficial effects of this invention are as follows: By adjusting the types of ligands and metal ions, this invention optimizes the performance of materials, making them more suitable for the treatment of specific types of organic pollutants. Furthermore, this invention is the first to synthesize three three-dimensional MOF materials based on novel pyrazole organic monomers with novel chemical structures. These three-dimensional MOF materials, with their unique electronic structures, promote the formation of catalytic active centers, accelerating the redox reactions of pollutants. They not only possess higher pollutant selectivity and larger adsorption capacity but also allow for material regeneration after simple treatment, reducing consumption and lowering overall treatment costs. In addition, these three-dimensional MOF materials exhibit excellent stability and adsorption performance under different environmental conditions, improving their applicability in various application scenarios. Attached Figure Description

[0025] Figure 1 The mass spectrum of the pyrazole organic monomer prepared in Example 1 is shown.

[0026] Figure 2 Crystal structure diagram of the three-dimensional Zn-MOF material prepared in Example 4; a) Coordination environment of Zn(II) in Zn-MOF, b) Three-dimensional structure of Zn-MOF - a axis, c) Three-dimensional structure of Zn-MOF - b axis, d) Three-dimensional structure of Zn-MOF - c axis.

[0027] Figure 3 The crystal structure diagram of the three-dimensional Co-MOF material prepared in Example 5 is shown below: a) Coordination environment of Co(II) in Co-MOF, b) Three-dimensional structure of Co-MOF - a-axis, c) Three-dimensional structure of Co-MOF - b-axis, d) Three-dimensional structure of Co-MOF - c-axis.

[0028] Figure 4 The crystal structure diagram of the three-dimensional Cu-MOF material prepared in Example 6 is shown below: a) Coordination environment of Cu(II) in Cu-MOF, b) Three-dimensional structure of Cu-MOF - a-axis, c) Three-dimensional structure of Cu-MOF - b-axis, d) Three-dimensional structure of Cu-MOF - c-axis.

[0029] Figure 5 The images show the XRD patterns of the Zn-MOF material prepared in Example 4 and the single-crystal simulated Zn-MOF material.

[0030] Figure 6 The images show the XRD patterns of the Co-MOF material prepared in Example 4 and the single-crystal simulated Co-MOF material.

[0031] Figure 7 The images show the XRD patterns of the Cu-MOF material prepared in Example 4 and the single-crystal simulated Cu-MOF material.

[0032] Figure 8 The images shown are SEM images and elemental analysis diagrams of the materials prepared in Example 4. a) SEM image and elemental analysis diagram of the three-dimensional Zn-MOF material prepared in Example 4; b) SEM image and elemental analysis diagram of the three-dimensional Co-MOF material prepared in Example 4; c) SEM image and elemental analysis diagram of the three-dimensional Cu-MOF material prepared in Example 4.

[0033] Figure 9 The graph shows the effect of pyrazole organic monomers prepared in Example 1, and Zn-MOF, Co-MOF and Cu-MOF prepared in Example 4 activating PMS to degrade organic pollutants of bisphenol A.

[0034] Figure 10 The graph shows the effect of pyrazole organic monomers prepared in Example 1, and Zn-MOF, Co-MOF and Cu-MOF prepared in Example 4 activating PMS to degrade organic pollutants of sulfadiazine.

[0035] Figure 11 The graph shows the effect of pyrazole organic monomers prepared in Example 1, and Zn-MOF, Co-MOF and Cu-MOF prepared in Example 4 activating PMS to degrade tetracycline organic pollutants.

[0036] Figure 12 The graph shows the effect of the pyrazole organic monomer prepared in Example 1, and the Zn-MOF, Co-MOF and Cu-MOF prepared in Example 4 on the degradation of organic pollutants of 17α-ethynylestradiol by activated PMS.

[0037] Figure 13 The graph shows the effect of pyrazole organic monomers prepared in Example 1, and Zn-MOF, Co-MOF and Cu-MOF prepared in Example 4 activating PMS to degrade organic pollutants such as methylene blue. Detailed Implementation

[0038] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0039] The tetra(4-bromophenyl)ethylene, 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxoron-2-yl)-1H-pyrazole, tetrabutylammonium bromide, tetra(triphenylphosphine)palladium, potassium carbonate, dichloromethane, sodium hydroxide, N,N-dimethylformamide, methanol, dimethyl sulfoxide, glacial acetic acid, sulfuric acid, zinc nitrate, cobalt nitrate, ethanol, and copper chloride used in this invention are all commercially available products.

[0040] Example 1

[0041] A method for preparing a pyrazole organic monomer includes the following steps:

[0042] (1) First, under an inert gas atmosphere, 0.15 mmol of tetra(4-bromophenyl)ethylene was added to 30 mL of xylene and stirred at room temperature for 5 minutes. Then, 1 mmol of 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxoron-2-yl)-1H-pyrazole, 0.2 g of tetrabutylammonium bromide, 80 mg of tetra(triphenylphosphine)palladium and 10 mL of 0.5 g / mL potassium carbonate solution were added to the reaction mixture and stirred.

[0043] (2) After refluxing at 110°C for 48 hours under an inert gas atmosphere and cooling to room temperature, the solution was rotary evaporated under pressure at 150°C. After rotary evaporation and cooling to room temperature, 100 mL of dichloromethane was added for dilution. The diluted solution was poured into a separatory funnel, 100 mL of water was added, and the mixture was shaken and allowed to stand for 5 minutes to remove unreacted metal catalysts and soluble impurities. The lower layer of the solution was transferred from the separatory funnel to a round-bottom flask and subjected to a second rotary evaporation (45 r / min, 60°C, under pressure). 50 mL of ethanol solution was added to the concentrate after rotary evaporation, followed by 10 mL of nitric acid and sonication for 30 minutes to form a light yellow suspension.

[0044] (3) Pour 20 mL of light yellow suspension into 200 mL of water, adjust the pH to 7 with 0.1 mol of sodium hydroxide to obtain a precipitate, wash with water 3 times, and dry to obtain polypyrazole organic monomer.

[0045] Example 2

[0046] A method for preparing a pyrazole organic monomer includes the following steps:

[0047] (1) First, under an inert gas atmosphere, 1 mmol of tetra(4-bromophenyl)ethylene was added to 100 mL of xylene and stirred at room temperature for 5 minutes. Then, 5 mmol of 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxoron-2-yl)-1H-pyrazole, 0.6 g of tetrabutylammonium bromide, 150 mg of tetra(triphenylphosphine)palladium and 20 mL of 0.4 g / mL potassium carbonate solution were added to the reaction mixture and stirred.

[0048] (2) After refluxing at 100°C for 72 hours under an inert gas atmosphere and cooling to room temperature, the solution was rotary evaporated under pressure at 150°C. After rotary evaporation and cooling to room temperature, 120 mL of dichloromethane was added for dilution. The diluted solution was poured into a separatory funnel, 120 mL of water was added, and the mixture was shaken and allowed to stand for 5 minutes to remove unreacted metal catalysts and soluble impurities. The lower layer of the solution was transferred from the separatory funnel to a round-bottom flask and subjected to a second rotary evaporation (45 r / min, 60°C, under pressure). 100 mL of ethanol solution was added to the concentrated solution after rotary evaporation, followed by 20 mL of nitric acid and sonication for 30 minutes to form a light yellow suspension.

[0049] (3) Pour 20 mL of light yellow suspension into 160 mL of water, adjust the pH to 7 with 0.1 mol of sodium hydroxide to obtain a precipitate, wash with water 3 times, and dry to obtain polypyrazole organic monomer.

[0050] The structure is the same as in Example 1.

[0051] Example 3

[0052] (1) First, under an inert gas atmosphere, 1.9 mmol of tetra(4-bromophenyl)ethylene was added to 160 mL of xylene and stirred at room temperature for 5 minutes. Then, 15 mmol of 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxoron-2-yl)-1H-pyrazole, 1.0 g of tetrabutylammonium bromide, 250 mg of tetra(triphenylphosphine)palladium and 40 mL of 0.8 g / mL potassium carbonate solution were added to the reaction mixture and stirred.

[0053] (2) After refluxing at 135°C for 24 hours under an inert gas atmosphere and cooling to room temperature, the solution was rotary evaporated under pressure at 150°C. After rotary evaporation and cooling to room temperature, 100 mL of dichloromethane was added for dilution. The diluted solution was poured into a separatory funnel, 100 mL of water was added, and the mixture was shaken and allowed to stand for 5 minutes to remove unreacted metal catalysts and soluble impurities. The lower layer of the solution was transferred from the separatory funnel to a round-bottom flask and subjected to a second rotary evaporation (45 r / min, 60°C, under pressure). 200 mL of ethanol solution was added to the concentrated solution after rotary evaporation, followed by 40 mL of nitric acid and sonication for 30 minutes to form a light yellow suspension.

[0054] (3) Pour 40 mL of light yellow suspension into 200 mL of water, adjust the pH to 7 with 0.1 mol of sodium hydroxide to obtain a precipitate, wash with water 3 times, and dry to obtain polypyrazole organic monomer.

[0055] The polypyrazole organic monomers prepared in Examples 1-3 are the same. The mass spectra of the pyrazole organic monomer prepared in Example 1 are as follows: Figure 1 As shown. According to Figure 1It can be seen that the pyrazole organic monomer was successfully prepared, and its structural formula is as follows:

[0056]

[0057] Example 4

[0058] A method for preparing a three-dimensional Zn-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 1 is dissolved in N,N-dimethylformamide to a concentration of 1 mg / mL, and the solution is sonicated for 5 min. 0.2 mL of the above solution is taken, and 1 mL of methanol, 0.4 mL of dimethyl sulfoxide, 0.1 mL of glacial acetic acid, 0.05 mL of sulfuric acid, and 0.1 mL of 0.02 g / mL zinc nitrate are added sequentially. The mixture is sonicated for 10 min, then reacted at 130 °C for 48 h at a heating rate of 20 °C / h, and then cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Zn-MOF material.

[0059] A method for preparing a three-dimensional Co-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 1 is dissolved in N,N-dimethylformamide to a concentration of 1 mg / mL, and the solution is sonicated for 5 min. 0.2 mL of the above solution is taken, and 1 mL of methanol, 0.4 mL of dimethyl sulfoxide, 0.3 mL of water, 0.1 mL of glacial acetic acid, 0.05 mL of sulfuric acid, and 0.1 mL of 0.02 g / mL cobalt nitrate are added sequentially. The mixture is sonicated for 5 min, then reacted at 130 °C for 48 h at a heating rate of 20 °C / h, and then cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Co-MOF material.

[0060] A method for preparing a three-dimensional Cu-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 1 is dissolved in N,N-dimethylformamide to a concentration of 1 mg / mL, and the solution is sonicated for 5 min. 0.2 mL of the solution is taken, and 1 mL of ethanol, 0.3 mL of dimethyl sulfoxide, 0.1 mL of glacial acetic acid, 0.05 mL of sulfuric acid, and 0.02 g / mL of copper chloride are added sequentially. The mixture is sonicated for 5 min, then reacted at 105 °C for 48 h at a heating rate of 20 °C / h, and cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Cu-MOF material.

[0061] Example 5

[0062] A method for preparing a three-dimensional Zn-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 2 is dissolved in dimethyl sulfoxide to a concentration of 2 mg / mL, and the solution is sonicated for 5 min. 0.2 mL of the solution is taken, and 1 mL of methanol, 0.3 mL of dimethyl sulfoxide, 0.1 mL of glacial acetic acid, 0.05 mL of sulfuric acid, and 0.1 mL of 0.02 g / mL zinc nitrate are added sequentially. The mixture is sonicated for 10 min, then reacted at 120 °C for 48 h at a heating rate of 10 °C / h, and cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Zn-MOF material.

[0063] A method for preparing a three-dimensional Co-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 2 is dissolved in dimethyl sulfoxide to a concentration of 2 mg / mL, and the solution is sonicated for 5 min. 0.2 mL of the above solution is taken, and 1 mL of methanol, 0.3 mL of dimethyl sulfoxide, 0.3 mL of water, 0.1 mL of glacial acetic acid, 0.05 mL of sulfuric acid, and 0.1 mL of 0.02 g / mL cobalt nitrate are added sequentially. The mixture is sonicated for 5 min, then reacted at 120 °C for 48 h at a heating rate of 10 °C / h, and then cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Co-MOF material.

[0064] A method for preparing a three-dimensional Cu-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 2 is dissolved in dimethyl sulfoxide, with the concentration of the pyrazole organic monomer prepared to be 2 mg / mL. The solution is then sonicated for 5 min. 0.2 mL of the above solution is taken, and 1 mL of ethanol, 0.2 mL of dimethyl sulfoxide, 0.1 mL of glacial acetic acid, 0.05 mL of sulfuric acid, and 0.1 mL of 0.02 g / mL copper chloride are added sequentially. The mixture is sonicated for 5 min, then reacted at 110 °C for 48 h at a heating rate of 10 °C / h, and then cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Cu-MOF material.

[0065] Example 6

[0066] A method for preparing a three-dimensional Zn-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 3 is dissolved in N,N-dimethylacetamide to a concentration of 5 mg / mL, and the solution is sonicated for 5 min. 0.4 mL of the above solution is taken, and 2 mL of methanol, 0.6 mL of dimethyl sulfoxide, 0.2 mL of glacial acetic acid, 0.1 mL of sulfuric acid, and 0.2 mL of 0.02 g / mL zinc nitrate are added sequentially. The mixture is sonicated for 10 min, then reacted at 130 °C for 48 h at a heating rate of 10 °C / h, and then cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Zn-MOF material.

[0067] A method for preparing a three-dimensional Co-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 3 is dissolved in N,N-dimethylacetamide to a concentration of 5 mg / mL, and the solution is sonicated for 5 min. 0.4 mL of the above solution is taken, and 2 mL of methanol, 0.6 mL of dimethyl sulfoxide, 0.5 mL of water, 0.2 mL of glacial acetic acid, 0.1 mL of sulfuric acid, and 0.2 mL of 0.02 g / mL cobalt nitrate are added sequentially. The mixture is sonicated for 5 min, then reacted at 120 °C for 56 h at a heating rate of 10 °C / h, and then cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Co-MOF material.

[0068] A method for preparing a three-dimensional Cu-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 3 is dissolved in N,N-dimethylacetamide to a concentration of 5 mg / mL, and the solution is sonicated for 5 min. 0.4 mL of the above solution is taken, and 2 mL of ethanol, 0.4 mL of dimethyl sulfoxide, 0.2 mL of glacial acetic acid, 0.1 mL of sulfuric acid, and 0.2 mL of 0.02 g / mL copper chloride are added sequentially. The mixture is sonicated for 5 min, then reacted at 110 °C for 12 h at a heating rate of 10 °C / h, and then cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Cu-MOF material.

[0069] Example 7

[0070] A method for preparing a three-dimensional Zn-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 1 is dissolved in N,N-dimethylacetamide to a concentration of 10 mg / mL, and the solution is sonicated for 5 min. 0.4 mL of the above solution is taken, and 2 mL of methanol, 0.8 mL of dimethyl sulfoxide, 0.2 mL of glacial acetic acid, 0.1 mL of sulfuric acid, and 0.2 mL of 0.02 g / mL zinc nitrate are added sequentially. The mixture is sonicated for 10 min, then reacted at 130 °C for 24 h at a heating rate of 5 °C / h, and then cooled to room temperature at a cooling rate of 10 °C / h to obtain the three-dimensional Zn-MOF material.

[0071] A method for preparing a three-dimensional Co-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 1 is dissolved in N,N-dimethylacetamide to a concentration of 10 mg / mL, and the solution is sonicated for 5 min. 0.4 mL of the above solution is taken, and 2 mL of methanol, 0.8 mL of dimethyl sulfoxide, 0.5 mL of water, 0.2 mL of glacial acetic acid, 0.1 mL of sulfuric acid, and 0.2 mL of 0.02 g / mL cobalt nitrate are added sequentially. The mixture is sonicated for 5 min, then reacted at 130 °C for 24 h at a heating rate of 5 °C / h, and then cooled to room temperature at a cooling rate of 10 °C / h to obtain the three-dimensional Co-MOF material.

[0072] A method for preparing a three-dimensional Cu-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 1 is dissolved in N,N-dimethylacetamide to a concentration of 10 mg / mL, and the solution is sonicated for 5 min. 0.4 mL of the above solution is taken, and 2 mL of ethanol, 0.4 mL of dimethyl sulfoxide, 0.2 mL of glacial acetic acid, 0.1 mL of sulfuric acid, and 0.2 mL of 0.02 g / mL copper chloride are added sequentially. The mixture is sonicated for 5 min, then reacted at 115 °C for 24 h at a heating rate of 5 °C / h, and then cooled to room temperature at a cooling rate of 10 °C / h to obtain the three-dimensional Cu-MOF material.

[0073] The crystal structures of the Zn-MOF, Co-MOF, and Cu-MOF metal-organic frameworks synthesized in Example 4 are as follows: Figure 2 , 3 As shown in Figure 4. The materials prepared in Examples 5-7 have the same structure as those prepared in Example 4. According to... Figure 5 , 6 XRD analysis of samples 7 and 8 shows that, based on the simulated XRD of the single-crystal structure of Zn-MOF, the Zn-MOF powder synthesized in Example 4 exhibits obvious peaks at 5.62°, 7.44°, 8.92°, 9.70°, 11.38°, and 18.24°. Similarly, based on the simulated XRD of the single-crystal structure of Co-MOF, the Co-MOF powder synthesized in Example 4 exhibits obvious peaks at 5.68°, 7.32°, 8.90°, 9.68°, 15.84°, and 17.90°. Furthermore, based on the simulated XRD of the single-crystal structure of Cu-MOF, the Cu-MOF powder synthesized in Example 4 exhibits obvious peaks at 5.14°, 7.20°, 9.92°, and 11.68°. The synthesized Zn-MOF, Co-MOF, and Cu-MOF powders all possess high crystallinity. Scanning electron microscope images of the synthesized Zn-MOF, Co-MOF, and Cu-MOF in Example 4 are shown below. Figure 8 As shown, Zn-MOF has a spherical morphology with sheet-like stacking, while Co-MOF and Cu-MOF have a blocky morphology.

[0074] Comparative Example 1

[0075] A method for preparing a three-dimensional Zn-MOF material includes the following steps: 1 mmol Zn(NO3)2 and 0.5 mmol sodium terephthalate are ultrasonically dissolved in 130 mL DMF, transferred to a reaction vessel and sealed, heated to 120 °C at a heating rate of 5 °C / min and reacted for 24 hours, the resulting material is washed three times with pure DMF and vacuum dried at 80 °C to obtain a three-dimensional Zn-MOF.

[0076] A method for preparing a three-dimensional Co-MOF material includes the following steps: 1.2 mmol Co(NO3)2 and 0.8 mmol 2-methylimidazole are ultrasonically dissolved in 120 mL of a mixed solution of DMF and EtOH (volume ratio 1:1), transferred to a reaction vessel and sealed, heated to 110 °C at a heating rate of 10 °C / min and reacted for 24 hours, the obtained material is washed three times with pure EtOH and vacuum dried at 80 °C to obtain a three-dimensional Co-MOF.

[0077] A method for preparing a three-dimensional Cu-MOF material includes the following steps: 0.8 mmol Cu(NO3)2 and 0.5 mmol 2-methylimidazole are ultrasonically dissolved in 120 mL EtOH solution, transferred to a reaction vessel and sealed, heated to 80 °C at a heating rate of 5 °C / min and reacted for 8 hours, the resulting material is washed three times with pure EtOH and vacuum dried at 80 °C to obtain a three-dimensional Cu-MOF.

[0078] Comparative Example 2

[0079] A method for preparing a three-dimensional Fe-MOF material includes the following steps: The pyrazole organic monomer prepared in Example 1 is dissolved in N,N-dimethylformamide to a concentration of 1 mg / mL, and the solution is sonicated for 5 min. 0.2 mL of the solution is taken, and 1 mL of methanol, 0.4 mL of dimethyl sulfoxide, 0.1 mL of glacial acetic acid, 0.05 mL of sulfuric acid, and 0.1 mL of 0.02 g / mL ferric nitrate are added sequentially. The mixture is sonicated for 10 min, then reacted at 130 °C for 48 h at a heating rate of 20 °C / h, and cooled to room temperature at a cooling rate of 5 °C / h to obtain the three-dimensional Fe-MOF material.

[0080] Example of effect 1

[0081] The degradation effects of the three MOF materials prepared in Examples 4-7 and Comparative Examples 1-2 on tetracycline, bisphenol A, sulfadiazine, 17α-ethynylestradiol, and methylene blue in different environments were investigated. The specific experiments are as follows:

[0082] Experiment 1: Eight 50 mL containers were taken, and 50 mL of aqueous solution containing tetracycline (20 mg / L) was added to each. Then, one container was filled with 10 mg of the polypyrazole ligand prepared in Example 1 (referred to as Lg), another with 10 mg of Lg and 0.5 μM PMS, one with 10 mg of Zn-MOF, one with 10 mg of Zn-MOF and 0.5 μM PMS, one with 10 mg of Co-MOF, one with 10 mg of Co-MOF and 0.5 μM PMS, one with 10 mg of Cu-MOF, and one with 10 mg of Cu-MOF and 0.5 μM PMS. All eight reactions were shaken for 45 minutes, and samples were taken at preset time intervals and filtered using a 0.45 μm filter. The adsorbed filtrate was collected in centrifuge tubes, and the TC content was determined by liquid chromatography at a column temperature of 30.0 °C. Elution: flow rate 0.6 mL / min, methanol:water (0.1% containing formic acid) = 50:50.

[0083] Experiment 2: The only difference between this experiment and Experiment 1 is that the organic pollutant is replaced with the same concentration of bisphenol A.

[0084] Experiment 3: The only difference between this experiment and Experiment 1 is that the organic pollutant was replaced with the same concentration of sulfadiazine.

[0085] Experiment 4: The only difference between this experiment and Experiment 1 is that the organic pollutant is replaced with the same concentration of 17α-ethynylestradiol.

[0086] Experiment 5: The only difference between this experiment and Experiment 1 is that the organic pollutant is replaced with the same concentration of methylene blue.

[0087] The results are as follows Figure 9-13As shown, Zn-MOF, Co-MOF, and Cu-MOF can all effectively activate PMS to generate reactive oxygen species, exhibiting excellent degradation effects on tetracycline (TC), bisphenol A (BPA), sulfadiazine (SDZ), 17α-ethynylestradiol (EE2), and methylene blue (MB). Among these, Co-MOF-activated PMS achieves a degradation rate of over 95% for multiple pollutants (TC, BPA, SDZ, EE2, MB), while Cu-MOF-activated PMS achieves a removal rate of over 90% for SDZ, TC, and EE2, unaffected by the complex environment of actual wastewater. Zn-MOF-activated PMS achieves a degradation rate of over 95% for TC. Zn-MOF, Co-MOF, and Cu-MOF all possess certain degradation capabilities for TC, BPA, SDZ, EE2, and MB, with Co-MOF showing the best degradation effect. Polypyrazole ligands and ligand-PMS systems are not effective at removing organic pollutants; their degradation of tetracycline, bisphenol A, sulfadiazine, 17α-ethynylestradiol, and methylene blue is less than 10%.

[0088] The Zn-MOF, Co-MOF, and Cu-MOF prepared in Examples 5-7 showed similar degradation effects on tetracycline, bisphenol A, sulfadiazine, 17α-ethynylestradiol, and methylene blue by reactive oxygen species generated from activated PMS as in Example 4. The Zn-MOF, Co-MOF, and Cu-MOF prepared in Comparative Example 1 showed degradation rates of less than 50% for tetracycline, bisphenol A, sulfadiazine, 17α-ethynylestradiol, and methylene blue by reactive oxygen species generated from activated PMS. The Fe-MOF prepared in Comparative Example 2 showed degradation rates of less than 60% for tetracycline, bisphenol A, sulfadiazine, 17α-ethynylestradiol, and methylene blue by reactive oxygen species generated from activated PMS.

[0089] Example 2

[0090] The Zn-MOF, Co-MOF or Cu-MOF that degraded organic pollutants in Example 1 were added to anhydrous ethanol and dried after 1 hour. The dried material was subjected to 5 activated PMS catalytic cycles. The degradation effect of the material prepared in Example 4 is shown in Tables 1-3.

[0091] Table 1 Zn-MOF+PMS

[0092] Loop count SDZ BPA TC MB EE2 1 73.45％ 36.98％ 16.31％ 58.16％ 60.05％ 2 70.11％ 30.26％ 13.15％ 57.31％ 53.72％ 3 69.33％ 28.31％ 13.62％ 55.51％ 48.31％ 4 69.12％ 26.12％ 12.99％ 51.89％ 45.69％ 5 68.94％ 25.19％ 12.56％ 50.66％ 44.44％

[0093] Table 2 Co-MOF+PMS

[0094] Loop count SDZ BPA TC MB EE2 1 99.46％ 99.33％ 98.65％ 99.72％ 99.89％ 2 96.31％ 94.36％ 95.31％ 97.21％ 99.01％ 3 95.61％ 93.99％ 93.44％ 96.55％ 98.34％ 4 94.39％ 93.12％ 91.35％ 95.71％ 97.05％ 5 94.65％ 92.87％ 90.06％ 95.23％ 96.39％

[0095] Table 3 Cu-MOF+PMS

[0096] Loop count SDZ BPA TC MB EE2 1 90.22％ 71.31％ 99.86％ 89.39％ 95.36％ 2 85.31％ 70.01％ 97.32％ 87.14％ 94.33％ 3 80.06％ 69.31％ 95.45％ 84.66％ 93.12％ 4 78.31％ 65.69％ 92.31％ 80.67％ 91.99％ 5 75.21％ 64.31％ 91.11％ 78.39％ 91.02％

[0097] As shown in Tables 1-3, the Zn-MOF, Co-MOF or Cu-MOF prepared in Example 4 still have good removal rates when activating PMS to catalyze a variety of organic pollutants. Therefore, the Zn-MOF, Co-MOF or Cu-MOF have good recyclability.

[0098] The Zn-MOF, Co-MOF, or Cu-MOF prepared in Examples 5-7 and Comparative Examples 1-2 exhibited good cycling stability. However, the Zn-MOF, Co-MOF, or Cu-MOF prepared in Comparative Examples 1-2 showed low degradation rates of organic pollutants catalyzed by PMS, below 50%.

[0099] Example 3

[0100] The degradation of organic pollutants by activated PMS was investigated using Co-MOF prepared in Example 4 or materials prepared in Comparative Examples 1-2 in tap water and actual water bodies. 10 mg of Co-MOF material was added to tap water or aqueous solutions of Dianchi Lake in Kunming, Yunnan Province, containing TC (20 mg / L), MB (20 mg / L), EE2 (3 mg / L), SDZ (20 mg / L), and BPA (20 mg / L), respectively. After adding 0.5 μM PMS, the reaction was shaken for 45 minutes. Samples were taken at preset time intervals and filtered using a 0.45 μm filter. The adsorbed filtrate was collected in centrifuge tubes, and the content of the corresponding pollutants was determined by liquid chromatography and ultraviolet spectroscopy. The degradation rates of organic pollutants are shown in Tables 4-5.

[0101] Table 4 Tap Water

[0102]

[0103] Table 5 Lake Water

[0104]

[0105] As shown in Table 4-5, under the catalysis of PMS, Co-MOF can still maintain a removal rate of over 93.65% for various pollutants under the water quality conditions of tap water or lake water, indicating that Co-MOF has promising application prospects.

[0106] The Zn-MOF, Co-MOF, Cu-MOF, or Fe-MOF prepared in Comparative Examples 1-2 showed weak anti-interference properties, and the degradation rate of organic matter catalyzed by activated PMS was less than 40%.

[0107] Example of effect 4

[0108] The simultaneous adsorption-degradation effect of Co-MOF on multiple pollutants in a mixed solution was investigated. 10 mg of Co-MOF or Co-MOF + PMS (0.5 μM) was added to a mixed solution containing TC, BPA, SDZ, EE2, and MB (3 mg / L for each pollutant). The reaction was shaken for 45 minutes, and samples were taken at preset time intervals and filtered using a 0.45 μm filter. The adsorbed filtrate was collected in centrifuge tubes, and the content of the corresponding pollutants was determined by liquid chromatography and ultraviolet spectroscopy. The degradation rates of organic pollutants are shown in Table 6.

[0109] Table 6

[0110]

[0111] As can be seen from Table 6, Co-MOF+PMS can remove multiple organic pollutants simultaneously, with degradation rates all maintained above 92.30%, demonstrating its potential for treating mixed pollutants in natural water bodies and wastewater.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A three-dimensional MOF material, characterized in that, Co-MOF metal-organic framework materials were prepared by a solvothermal method using an organic monomer with the structural formula (Ⅰ) as a ligand and cobalt salt as a metal salt. The structural formula of the organic monomer is shown in formula (Ⅰ):

2. The three-dimensional MOF material as described in claim 1, characterized in that, The method for preparing the organic monomer with the structural formula (Ⅰ) includes the following steps: (1) Tetra(4-bromophenyl)ethylene, 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxoron-2-yl)-1H-pyrazole, tetrabutylammonium bromide and tetra(triphenylphosphine)palladium are added to organic solvent A under an inert gas atmosphere, and alkaline solution B is added and stirred or sonicated to obtain a mixed solution; (2) Then, after heating and refluxing in an inert gas atmosphere and cooling to room temperature, after rotary evaporation, extraction and rotary evaporation, alcohol and acid A are added and sonicated, and then stirred until the acidification reaction is completed to obtain a suspension. (3) After adjusting the pH to 7 by pouring the suspension into water, a precipitate was obtained. The precipitate was washed and dried to obtain an organic monomer with the structural formula (Ⅰ).

3. The three-dimensional MOF material as described in claim 2, characterized in that, The molar ratio of tetra(4-bromophenyl)ethylene to 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxoron-2-yl)-1H-pyrazole is 1:(5-8); the mass ratio of tetrabutylammonium bromide to tetra(triphenylphosphine)palladium is (0.2-1.0):(0.08-0.25); and the mass ratio of tetra(4-bromophenyl)ethylene to tetrabutylammonium bromide is (1.8-2.5):(0.8-1).

4. The three-dimensional MOF material as described in claim 2, characterized in that, The organic solvent A is xylene or toluene; the alkaline solution B is an aqueous solution of potassium carbonate, the volume of which does not exceed 10% of the total volume of the mixed solution, and the mass concentration of potassium carbonate in the aqueous solution is 0.4 g / mL-0.8 g / mL; the alcohol is methanol or ethanol, and the acid A is nitric acid, hydrochloric acid, or sulfuric acid; the acidification reaction takes 4-8 hours; the extractant used for extraction is a mixture of solvent and water, the solvent being dichloromethane or dichloroethane, and the volume ratio of solvent to water being 1:(0.5-1).

5. The three-dimensional MOF material as described in claim 2, characterized in that, In step (2), the temperature of the heating reflux is 100-135℃ and the time is 24-72h. The heating reflux method is oil bath or sand bath. In step (3), the volume ratio of the suspension to water is 1:(5-10).

6. A method for preparing a three-dimensional MOF material, characterized in that, The process includes the following steps: dissolving an organic monomer with the structural formula (Ⅰ) in organic solvent B to obtain a mixture, then adding organic solvent C and a metal salt and heating to obtain Co-MOF; the metal salt is a cobalt salt; The structural formula of the organic monomer is shown in formula (Ⅰ):

7. The method for preparing the three-dimensional MOF material as described in claim 6, characterized in that, In the preparation of Co-MOF, the organic solvent C is a mixed solution of methanol, water, dimethyl sulfoxide, acid B and acid C in a volume ratio of 1:0.1-0.3:0.3-0.5:0.07-0.1:0.005-0.05; wherein the organic solvent B is dimethyl sulfoxide, N,N-dimethylformamide or N,N-dimethylacetamide; acid B is glacial acetic acid; acid C is a 10% sulfuric acid solution by mass; the mass concentration of the organic monomer with structural formula (Ⅰ) in the mixed solution is 1-10 mg / mL; the amount of cobalt salt is 0.01-0.02 g / mL and the volume is 0.1-0.2 mL.

8. The method for preparing the three-dimensional MOF material as described in claim 6, characterized in that, The heating temperature is 100-130℃, the time is 12-56h, the heating rate is 10-20℃ / hour, and the cooling rate is 5-10℃ / hour.

9. The application of the three-dimensional MOF material as described in any one of claims 1-5 in the removal of organic pollutants, characterized in that, The three-dimensional MOF material is Co-MOF.

10. The application of the three-dimensional MOF material as described in any one of claims 1-5 in activating PMS to remove organic pollutants from water.

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