Method for large-scale synthesis of MAF-32 material, material and application
By reacting zinc salt with 2-ethylimidazole in deionized water, combined with stirring, centrifugation and vacuum drying steps, the green, economical and efficient large-scale synthesis of MAF-32 materials was successfully achieved, solving the problems of environmental pollution and high costs in the existing technology, and is suitable for industrial promotion.
Patent Information
- Application Number
- CN202510283033.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-11
- Publication Date
- 2025-06-10
AI Technical Summary
The existing MAF-32 materials synthesis methods require the use of solvents such as methanol and ammonia water, which leads to increased environmental pollution and costs. At the same time, it is easy to generate heterogeneous phases in large-scale production, making it difficult to achieve green, economical and efficient synthesis.
The zinc salt and 2-ethylimidazole were used to react in deionized water, and the MAF-32 material was prepared by stirring and centrifugation. The washing liquid and filtrate were used for continuous preparation, reducing the amount of deionized water, and a high yield of MAF-32 material was obtained by vacuum drying.
It has achieved green, economical and efficient large-scale synthesis of MAF-32 materials, reduced equipment costs and operating costs, reduced pollution and waste, and is suitable for industrial promotion.
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Figure CN120118325A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of preparation of metal-organic framework materials, and relates to a method for large-scale synthesis of MAF-32 materials, the materials and their applications. Background Art
[0002] Metal-organic framework (MOFs) materials are porous molecular framework materials constructed by inorganic metal ions and organic molecules through coordination bonds, and their structures have high tunability. At present, MOFs have been widely used in the fields of optics, energy storage, pollutant adsorption, magnetism, catalysis, etc. Metal azolate framework (MAFs) materials, also known as zeolitic imidazolate framework (ZIFs) materials, are a type of MOFs, which have the characteristics of low cost, easy to synthesize in large quantities, high pore volume, high hydrophobicity, high thermal stability and chemical stability. The synthesis and application background of MAF materials can be traced back to 2006 (Angew. Chem. Int. Ed., 2006, 45, 1557–1559), when the team of Academician Chen Xiaoming at Sun Yat-sen University synthesized MAF-4 (ZIF-8) through this method. This material is usually obtained by assembling 2-methylimidazole ligand (soft Lewis base) and metal Zn2+ ions (soft Lewis acid), and has wide applications in the fields of catalysis, separation and storage, etc. [Zn(eim) 2 (where eim = 2-ethylimidazole) is a typical MAF system, showing supramolecular isomerism and having three topological isomers, namely MAF-5, MAF-6 and MAF-32, which have distinct framework topologies and pore structures (J. Am. Chem. Soc., 2015, 137, 7217–7223). MAF-32 has important applications in aspects such as adsorption and removal of organic pollutants, preparation of porous carbon materials, particulate filtration, carbon dioxide separation and environmental remediation. In the currently reported methods for the synthesis and preparation of MAF-32, methanol and ammonia water, etc. (J. Am. Chem. Soc., 2015, 137, 7217–7223) are required, which will have a certain impact on the environment, increase the cost at the same time, and it is easy to generate impurity phases during the large-scale production process. Based on the above problems, it is very meaningful to develop a green, economical and efficient method for large-scale synthesis of MAF-32 materials. Summary of the Invention
[0003] In order to solve the technical problems existing in the prior art, the present invention provides a method for large-scale synthesis of MAF-32 materials, the materials and their applications. The synthesis technology of the present invention has the advantages of simple technology, low energy consumption, less pollution, short time consumption, low cost, high yield, etc., and can be scaled up for large-scale production.
[0004] The technical solution of the present invention:
[0005] A method for large-scale synthesis of MAF-32 material, comprising the following steps:
[0006] (1) Stir and dissolve zinc salt in deionized water to obtain solution A;
[0007] (2) Stir and dissolve 2-ethylimidazole in deionized water to obtain solution B;
[0008] (3) Add solution A to solution B and continuously stir to obtain emulsion C;
[0009] (4) Centrifuge and separate emulsion C to obtain liquid D and solid E;
[0010] (5) Wash solid E with deionized water to obtain washed solid E and washing liquid F, wherein the washed solid E is dried to obtain MAF-32 material;
[0011] Among them, by mixing liquid D and washing liquid F, the deionized water in step (2) can be replaced for the dissolution of 2-ethylimidazole, realizing the saving of deionized water in the continuous preparation of MAF-32 material.
[0012] Further, in step (1), the zinc salt is zinc acetate dihydrate, i.e., Zn(CH 3 COO) 2 ·2H 2 O, zinc nitrate hexahydrate, i.e., Zn(NO 3 ) 2 ·6H 2 O and zinc chloride, i.e., ZnCl 2 or one or more of them, and the concentration of the zinc salt in solution A is 0.05 - 0.2 mol / L.
[0013] Further, in step (2), the concentration of 2-ethylimidazole in solution B is 0.25 - 0.75 mol / L.
[0014] Further, the stirring in steps (1), (2) and (3) is carried out at room temperature, wherein the stirring time in steps (1) and (2) is 5 - 10 min, and the stirring time in step (3) is 1 - 24 h; preferably, the stirring time in step (3) is 3 h.
[0015] Further, when solution A and solution B are mixed, the concentration ratio of the zinc salt to 2-ethylimidazole in solution C is 0.05 - 0.2:0.25 - 0.75.
[0016] Further, the centrifugal speed in step (4) is 10000 - 15000 r / min and the time is 5 - 10 min.
[0017] Further, the drying in step (5) is vacuum drying, the drying temperature is 60 - 100 °C, and the drying time is 12 - 24 h.
[0018] Further, the yield of the MAF-32 material obtained in step (5) is 90 - 99%.
[0019] A MAF-32 material obtained by using any of the described methods, and the MAF-32 material is in the form of a white powder.
[0020] The application of the described MAF-32 material in the fields of adsorbing and removing organic pollutants, preparing porous carbon materials, particulate filtration, carbon dioxide separation, and environmental remediation.
[0021] Compared with the prior art, the present invention has the following advantages or effects:
[0022] (1) The process of the present invention is simple and can be produced by stirring at normal temperature and pressure in a short time. Therefore, no heating equipment is required during the material synthesis process, and at the same time, a reactor resistant to high temperature and high pressure is not needed, greatly reducing the equipment cost and operation cost during the material preparation process. Therefore, this method has the advantages of low equipment requirements, low energy consumption, short time consumption, and good repeatability, and can achieve large-scale synthesis.
[0023] (2) The solvent used in the preparation process of the material of the present invention is deionized water, while organic solvents are used as solvents in the prior art. Deionized water has the advantages of being cheap and easily available and having no pollution to the environment, and is the most economical and green choice among all solvents.
[0024] (3) The filtrate and cleaning solution obtained by centrifugation in the present invention can both be recycled and reused for the preparation of MAF-32. While reducing the water usage, the ligand remaining after the reaction in the MAF-32 preparation process, that is, 2-ethylimidazole, can be maximally utilized, reducing the waste of the ligand.
[0025] In summary, the present invention has the advantages of simple synthesis technology, low energy consumption, less pollution, short time consumption, low cost, high yield, etc., and is very suitable for industrial promotion. Description of the Drawings
[0026] Figure 1 It is the XRD pattern of the MAF-32 material prepared in Example 1 of the present invention;
[0027] Figure 2 It is the SEM pattern of the MAF-32 material prepared in Example 1 of the present invention;
[0028] Figure 3 It is the thermogravimetric pattern of the MAF-32 material prepared in Example 1 of the present invention;
[0029] Figure 4 Infrared spectrum of the MAF-32 material prepared in Example 1 of the present invention. Detailed implementation manners
[0030] The technical solutions of the present invention will be further clarified below in conjunction with embodiments. However, these embodiments do not limit the protection scope of the present invention. Based on the technical solutions of the present invention, various modifications or deformations that can be made by those skilled in the art without creative efforts are still within the protection scope of the present invention.
[0031] Example 1
[0032] Zn(NO 3 ) 2 ·6H 2 O (14.870 g, 0.050 mol) was dissolved in 500 mL of deionized water by stirring at room temperature for 6 min to obtain solution A; 2-ethylimidazole (24.032 g, 0.250 mol) was dissolved in 500 mL of deionized water by stirring at room temperature for 6 min to obtain solution B; solution A was added to solution B, and the mixture was continuously stirred at room temperature for 3 h to obtain a white emulsion C; the white emulsion C was centrifuged at 10,000 r / min for 5 min using a centrifuge to obtain a colorless liquid D and a white solid E; the white solid E was repeatedly washed with deionized water several times, and the washed white solid E was dried in vacuo at 80 °C for 12 h to obtain 12.307 g of a white powdery MAF-32 material, with a yield of 96.29%.
[0033] It can be seen through Figure 1 that the diffraction peaks of the MAF-32 material prepared by the process of Example 1 of the present invention coincide with the positions of the diffraction peaks of MAF-32 reported in the literature, indicating that the material prepared by this method is MAF-32.
[0034] It can be seen through Figure 2 that the MAF-32 material prepared by the process of Example 1 of the present invention is spherical with a size of 400 - 600 nm.
[0035] It can be seen through Figure 3 that the MAF-32 material prepared by the process of Example 1 of the present invention has high thermal stability.
[0036] It can be seen through Figure 4 that the MAF-32 material prepared by the process of Example 1 of the present invention has multiple characteristic absorption peaks in the range of 400 - 4000 cm -1 range.
[0037] Example 2
[0038] ZnCl 2(6.816 g, 0.050 mol) was dissolved in 500 mL of deionized water by stirring at room temperature for 8 min to obtain solution A; 2-ethylimidazole (24.032 g, 0.250 mol) was dissolved in 500 mL of deionized water by stirring at room temperature for 8 min to obtain solution B; solution A was added to solution B, and the mixture was continuously stirred at room temperature for 3 h to obtain a white emulsion C; the white emulsion C was centrifuged at 10000 r / min for 5 min using a centrifuge to obtain a colorless liquid D and a white solid E; the white solid E was washed repeatedly with deionized water, and the washed white solid E was dried in vacuo at 80 °C for 12 h to obtain 12.022 g of a white powdery MAF-32 material, with a yield of 94.06%.
[0039] Example 3
[0040] Zn(CH 3 COO) 2 ·2H 2 O (10.976 g, 0.050 mol) was dissolved in 500 mL of deionized water by stirring at room temperature for 7 min to obtain solution A; 2-ethylimidazole (24.032 g, 0.250 mol) was dissolved in 500 mL of deionized water by stirring at room temperature for 7 min to obtain solution B; solution A was added to solution B, and the mixture was continuously stirred at room temperature for 3 h to obtain a white emulsion C; the white emulsion C was centrifuged at 10000 r / min for 5 min using a centrifuge to obtain a colorless liquid D and a white solid E; the white solid E was washed repeatedly with deionized water, and the washed white solid E was dried in vacuo at 80 °C for 12 h to obtain 11.978 g of a white powdery MAF-32 material, with a yield of 93.72%.
[0041] Example 4
[0042] Zn(NO 3 ) 2 ·6H 2 O (14.870 g, 0.050 mol) was dissolved in 400 mL of deionized water by stirring at room temperature for 9 min to obtain solution A; 2-ethylimidazole (24.032 g, 0.250 mol) was dissolved in 400 mL of deionized water by stirring at room temperature for 9 min to obtain solution B; solution A was added to solution B, and the mixture was continuously stirred at room temperature for 3 h to obtain a white emulsion C; the white emulsion C was centrifuged at 10000 r / min for 5 min using a centrifuge to obtain a colorless liquid D and a white solid E; the white solid E was washed repeatedly with deionized water, and the washed white solid E was dried in vacuo at 80 °C for 12 h to obtain 12.202 g of a white powdery MAF-32 material, with a yield of 95.47%.
[0043] Example 5
[0044] Will Zn(NO 3 ) 2 6H 2 O (14.870 g, 0.050 mol) was dissolved in 500 mL of deionized water under stirring for 10 min at room temperature to obtain solution A; 2-ethylimidazole (24.032 g, 0.250 mol) was dissolved in 500 mL of deionized water under stirring for 10 min at room temperature to obtain solution B; solution A was added to solution B and stirred continuously at room temperature for 3 h to obtain a white emulsion C; the white emulsion C was centrifuged at 10000 r / min for 5 min to obtain a colorless liquid D and a white solid E; the white solid E was repeatedly washed with deionized water for several times, and the washed white solid E was vacuum dried at 60°C for 24 h to obtain 12.122 g of white powdery MAF-32 material with a yield of 94.84%.
[0045] Example 6
[0046] Will Zn(NO 3 ) 2 6H 2 O (14.870g, 0.050mol) was dissolved in 500mL deionized water under stirring for 10min at room temperature to obtain solution A; 2-ethylimidazole (24.032g, 0.250mol) was dissolved in a mixed solution consisting of 500mL of liquid D obtained in Example 5 and washing liquid F under stirring for 10min at room temperature to obtain solution B; solution A was added to solution B and stirred continuously for 3h at room temperature to obtain white emulsion C; the white emulsion C was centrifuged at 10000r / min for 5min to obtain colorless liquid D and white solid E; the white solid The solid E was repeatedly washed with deionized water for several times, and the washed white solid E was vacuum dried at 60° C. for 24 h to obtain 12.542 g of white powdery MAF-32 material with a yield of 98.13%. It can be seen that in Example 6, the mixed solution composed of liquid D and washing liquid F in Example 5 was used to replace deionized water to dissolve 2-ethylimidazole. Since the mixed solution composed of liquid D and washing liquid F contained residual ligand (2-ethylimidazole), more products were finally obtained with higher yield, which maximized the utilization of residual ligands and reduced the waste of ligands.
[0047] Through the above examples, compared with the currently reported MAF-32 synthesis preparation method which requires the use of methanol and ammonia water (J.Am.Chem.Soc., 2015, 137, 7217-7223), it can be seen that the present invention has the advantages of simple synthesis technology, low energy consumption, less pollution, short time consumption, low cost, high yield, etc., and is very suitable for industrial promotion.
[0048] The above-mentioned specific implementation methods are used to explain the present invention and are only preferred embodiments of the present invention, rather than limiting the present invention. Any modifications, equivalent substitutions, improvements, etc. made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.
Claims
1. A method for large-scale synthesis of MAF-32 material, characterized in that: The following steps are involved: (1) stirring and dissolving zinc salt in deionized water to obtain solution A; (2) dissolving 2-ethylimidazole in deionized water with stirring to obtain solution B; (3) adding solution A to solution B and stirring continuously to obtain emulsion C; (4) centrifuging the emulsion C to obtain liquid D and solid E; (5) washing the solid E with deionized water to obtain a washed solid E and a washing liquid F, wherein the washed solid E is dried to obtain a MAF-32 material; The liquid D and the washing liquid F are mixed to replace the deionized water in step (2) for dissolving 2-ethylimidazole.
2. The method for large-scale synthesis of MAF-32 material according to claim 1, characterized in that: In step (1), the zinc salt is one or more of zinc acetate dihydrate, i.e., Zn(CH3COO)2·2H2O, zinc nitrate hexahydrate, i.e., Zn(NO3)2·6H2O, and zinc chloride, i.e., ZnCl2, and the concentration of the zinc salt in solution A is 0.05 to 0.2 mol / L.
3. The method for large-scale synthesis of MAF-32 material according to claim 1, characterized in that: In step (2), the concentration of 2-ethylimidazole in the solution B is 0.25 to 0.75 mol / L.
4. The method for large-scale synthesis of MAF-32 material according to claim 1, characterized in that: The stirring in step (1), step (2) and step (3) is carried out at room temperature, wherein the stirring time in step (1) and step (2) is 5 to 10 minutes, and the stirring time in step (3) is 1 to 24 hours.
5. The method for large-scale synthesis of MAF-32 material according to claim 1, characterized in that: When the solution A is mixed with the solution B, the concentration ratio of the zinc salt to the 2-ethylimidazole in the solution C is 0.05-0.2:0.25-0.
75.
6. The method for large-scale synthesis of MAF-32 material according to claim 1, characterized in that: The centrifugal speed in step (4) is 10000-15000 r / min, and the time is 5-10 min.
7. The method for large-scale synthesis of MAF-32 material according to claim 1, characterized in that: The drying in step (5) is vacuum drying, the drying temperature is 60 to 100° C., and the drying time is 12 to 24 hours.
8. The method for large-scale synthesis of MAF-32 material according to claim 1, characterized in that: The yield of the MAF-32 material obtained in step (5) is 90-99%.
9. A MAF-32 material, characterized in that: The MAF-32 material is obtained by any method as described in claims 1-9, and is in the form of white powder.
10. Application of the MAF-32 material according to claim 9 in the fields of adsorption and removal of organic pollutants, preparation of porous carbon materials, particulate matter filtration, carbon dioxide separation and environmental remediation.