A mild preparation method of a needle-shaped aldehyde-based porphyrin covalent organic framework material and application thereof

Abstract

The present application relates to the technical field of porphyrin-based covalent organic framework material preparation, in particular to a mild preparation method of acetaldehyde-based porphyrin covalent organic framework and application thereof, which comprises the following steps: step one: dispersing ligand 2', 5'-bis((ethyl sulfide) methyl)-[1,1':4',1''-triphenyl]-4,4''-diamine in acetonitrile solution to obtain solution A, and dissolving acetaldehyde-based porphyrin in dichloromethane to obtain solution B; step two: mixing solution A and solution B; step three: adding ferric chloride and acetic acid as catalysts to react under mild conditions to obtain acetaldehyde-based porphyrin covalent organic framework material, which has excellent gaseous iodine adsorption performance. The synthesis method provided by the present application has mild conditions, simplifies the high-temperature time-consuming shortcomings of traditional porphyrin-based covalent organic framework material synthesis, and realizes the synthesis of special ligand covalent organic framework.

Description

Technical Field

[0001] This invention relates to the field of porphyrin-based covalent organic framework material preparation technology, specifically to a mild preparation method for needle-like aldehyde-based porphyrin covalent organic framework materials and their applications. Background Technology

[0002] Covalent organic frameworks are novel porous materials with unique structures and properties. They possess advantages such as highly ordered pore structures, large specific surface areas, high porosity, and the availability of numerous active sites, which are beneficial for gas adsorption, molecular recognition, and catalytic reactions. By selecting different organic building blocks and connection methods, pore size, pore shape, and chemical functions can be precisely controlled to meet the needs of various application fields such as gas storage and separation, catalytic environmental monitoring and sensing, and biomedicine. In the nuclear energy field, various highly toxic and volatile radionuclides are generated, among which radioactive iodine isotopes are one of the key hazardous components in nuclear waste. These radioactive iodines not only have strong biotoxicity, entering the human body through the respiratory tract and food chain, causing permanent damage to organs such as the thyroid gland, but also pose a long-term and serious threat to the ecological environment and human health once leaked due to their high volatility and difficulty in control. Therefore, developing efficient, stable, and economical radioactive iodine capture and fixation technologies has become an urgent problem to be solved in the field of nuclear waste management.

[0003] Currently, the preparation of covalent organic frameworks mainly involves traditional methods such as solvothermal methods, ionothermal methods, mechanochemical synthesis, and microwave-assisted synthesis. The solvothermal method primarily involves mixing monomers, solvents, and catalysts in a sealed container and reacting them at high temperatures (80-200℃) for several days to form ordered crystal structures through reversible covalent bonds. However, these traditional methods still have shortcomings, such as difficulty in simultaneously achieving both crystallinity and stability of the obtained covalent organic frameworks, demanding synthesis conditions, and insufficient environmental friendliness. In particular, it is difficult to obtain ordered covalent organic framework structures composed of certain special ligands. Therefore, developing a method for preparing porphyrin-based covalent organic framework materials under mild conditions has become an urgent problem to be solved. Summary of the Invention

[0004] To address the limitations of existing synthetic methods in obtaining ordered covalent organic framework structures composed of specific ligands, this invention provides a mild method for preparing needle-like aldehyde-based porphyrin covalent organic framework materials. The synthetic method provided by this invention operates under mild conditions, simplifying the high-temperature and time-consuming drawbacks of traditional porphyrin-based covalent organic framework material synthesis, and enabling the synthesis of covalent organic frameworks with specific ligands. Furthermore, this material exhibits excellent gaseous iodine adsorption and cycling stability.

[0005] Another object of the present invention is to provide a needle-shaped aldehyde porphyrin covalent organic framework material prepared by the above preparation method.

[0006] This invention also provides applications of the above-mentioned needle-shaped aldehyde porphyrin covalent organic framework material.

[0007] The technical solution adopted by the present invention to achieve the above objectives is as follows: This invention provides a mild method for preparing needle-like aldehyde porphyrin covalent organic framework materials, comprising the following steps: (1) Disperse the ligand 2',5'-bis((ethio)methyl)-[1,1':4',1''-terphenyl]-4,4''-diamine in acetonitrile solution to obtain solution A; (2) Dissolve tetraaldehyde phenylporphyrin in dichloromethane to obtain solution B; (3) Mix solution A and solution B; then slowly add ferric chloride acetonitrile solution and acetic acid, react under mild conditions, wash and dry to obtain needle-shaped aldehyde porphyrin covalent organic framework.

[0008] Preferably, in step (1), the concentration of 2',5'-bis((ethio)methyl)-[1,1':4',1''-terphenyl]-4,4''-diamine in solution A is 0.5~1.0 g / L.

[0009] Preferably, in step (2), the concentration of tetraaldehyde phenylporphyrin in solution B is 0.4~0.6 g / L.

[0010] Preferably, in step (3), the volume ratio of solution A to solution B is 0.8~1.2:1.

[0011] Preferably, in step (3), the concentration of the ferric chloride acetonitrile solution is 50 g / L; based on solution B, the amount of ferric chloride acetonitrile solution added to every 2.0 mL of solution B is 0.46~0.77 mmol, and the amount of acetic acid added is 5.25~10.50 mmol.

[0012] Preferably, in step (3), the reaction is carried out at a temperature of 50~80℃ for 2~6 hours with stirring.

[0013] Preferably, in step (3), acetone is used for centrifugal washing; the drying method is drying in a blower drying oven for 2 to 5 hours.

[0014] The present invention also provides a needle-shaped aldehyde porphyrin covalent organic framework material prepared by the above preparation method.

[0015] Another object of the present invention is to provide the application of the above-mentioned needle-shaped aldehyde porphyrin covalent organic framework material as a gaseous iodine adsorbent material.

[0016] Preferably, the needle-shaped aldehyde porphyrin covalent organic framework material is used for gaseous iodine adsorption in the field of radioactive waste recycling.

[0017] This invention provides a mild preparation method for needle-shaped aldehyde porphyrin covalent organic frameworks and their applications. First, the ligand 2',5'-bis((ethylthio)methyl)-[1,1':4',1''-terphenyl]-4,4''-diamine is dispersed in acetonitrile solution to obtain solution A, and tetraaldehyde phenyl porphyrin is dissolved in dichloromethane to obtain solution B. Second, solutions A and B are mixed. Finally, ferric chloride and acetic acid are added as catalysts, and the reaction is carried out under mild conditions to obtain needle-shaped aldehyde porphyrin covalent organic framework materials.

[0018] The structural formula of the tetraaldehyde phenylporphyrin used in this invention is: .

[0019] The structural formula of 2',5'-bis((ethio)methyl)-[1,1':4',1''-terphenyl]-4,4''-diamine used in this invention is: .

[0020] The beneficial effects of this invention are: (1) The preparation method provided by the present invention is mild and highly operable, and can obtain covalent organic framework structure materials composed of special ligands under mild conditions, simplifying the high temperature and time-consuming disadvantages of traditional porphyrin-based covalent organic framework material synthesis, and realizing the synthesis of special ligand covalent organic frameworks; (2) The covalent organic framework structure material prepared by the present invention has excellent gaseous iodine adsorption and cycle stability. Through structural optimization and functional design of the covalent organic framework material, excellent iodine adsorption performance can be achieved. It has large capacity and good stability, and can be used for the recovery of radioactive iodine in the field of radioactive nuclear waste recycling, which is of great significance to the safe utilization of nuclear energy. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 Example 1: Schematic diagram of the synthesis of needle-shaped aldehyde porphyrin covalent organic framework: Figure 2 Transmission electron microscopy image of needle-shaped aldehyde porphyrin covalent organic framework in Example 1; Figure 3 Example 1: High-magnification transmission electron microscopy image of a needle-like aldehyde porphyrin covalent organic framework; Figure 4Example 1: Elemental distribution diagram of needle-shaped aldehyde porphyrin covalent organic framework; Figure 5 Example 1: XRD pattern of needle-shaped aldehyde porphyrin covalent organic framework; Figure 6 Transmission electron microscopy image of needle-shaped aldehyde porphyrin covalent organic framework in Example 2: Figure 7 Example 2: High-magnification transmission electron microscopy image of a needle-like aldehyde porphyrin covalent organic framework; Figure 8 Example 2: XRD pattern of needle-shaped aldehyde porphyrin covalent organic framework; Figure 9 Example 1: Adsorption effect of gaseous iodine on needle-shaped aldehyde porphyrin covalent organic framework at different times; Figure 10 Example 1: Gaseous iodine adsorption cycle diagram of needle-shaped aldehyde porphyrin covalent organic framework. Detailed Implementation

[0023] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments and accompanying drawings, further clarifies the invention. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention. Based on this explanation, those skilled in the art can readily conceive of specific embodiments of the present invention without inventive effort, and all related methods of the present invention will fall within the scope of protection of the present invention.

[0024] In this invention, unless otherwise specified, the preparation methods are all conventional preparation methods, and the reagents used are all obtained from publicly available commercial sources or according to existing methods unless otherwise specified.

[0025] Example 1 Step 1: Prepare 2.0 mL of acetonitrile solution of 2',5'-bis((ethylthio)methyl)-[1,1':4',1''-terphenyl]-4,4''-diamine (CAS: 2231404-37-6) with a concentration of 0.75 g / L as Solution A, and prepare 2.0 mL of dichloromethane solution of tetraaldehyde phenylporphyrin with a concentration of 0.5 g / L as Solution B.

[0026] Step 2: Mix solution A and solution B from Step 1 to obtain a mixed solution; Step 3: Slowly add 0.2 mL of ferric chloride acetonitrile solution (50 g / L) and 0.5 mL of acetic acid to the mixed solution obtained in Step 2. Stir the reaction at 70℃ for 2 hours, wash with acetone by centrifugation, and dry in a forced-air environment for 3 hours to obtain needle-shaped aldehyde-porphyrin covalent organic framework material. (Synthesis diagram) Figure 1 As shown.

[0027] The results showed that the covalent organic framework material was elongated needle-like, with a length of 1–3 μm and a width of approximately 100–200 nm. Figure 2 Meanwhile, this needle-like aldehyde porphyrin covalent organic framework material exhibits excellent crystallinity and distinct lattice fringes. Figure 3 ); C, N, S and other elements are evenly distributed ( Figure 4 XRD data show that this material has excellent crystallinity. Figure 5 ).

[0028] Example 2 Step 1: Prepare 2.0 mL of acetonitrile solution of 2',5'-bis((ethylthio)methyl)-[1,1':4',1''-terphenyl]-4,4''-diamine with a concentration of 1.0 g / L as solution A, and prepare 2.0 mL of dichloromethane solution of tetraaldehyde phenylporphyrin with a concentration of 0.6 g / L as solution B.

[0029] Step 2: Mix solution A and solution B from Step 1 to obtain a mixed solution; Step 3: Slowly add 0.2 mL of ferric chloride acetonitrile solution (50 g / L) and 0.5 mL of acetic acid to the mixed solution obtained in Step 2. Stir the reaction at 70℃ for 2 hours, wash with acetone by centrifugation, and dry with forced air for 3 hours to obtain needle-shaped aldehyde porphyrin covalent organic framework material.

[0030] The results showed that the covalent organic framework material was elongated needle-like, with a length of 1–3 μm and a width of approximately 100–200 nm. Figure 6 Meanwhile, this needle-like aldehyde porphyrin covalent organic framework material exhibits excellent crystallinity and distinct lattice fringes. Figure 7 XRD data show that this material has excellent crystallinity. Figure 8 ).

[0031] Example 3 Accurately weigh 10 mg of the needle-shaped aldehyde porphyrin covalent organic framework material prepared in Example 1 and place it in a 2 mL open-top glass bottle, accurately weighing its mass. Then, place it into a 10 mL large glass bottle containing 800 mg of iodine granules. After sealing, place it in a 75°C constant temperature oven. Weigh the small glass bottle at 0, 1, 24, 8, 12, 24, 48, and 72 hours and record the data. Perform iodine desorption on this group of materials under vacuum and 100°C for 6 hours, repeat the iodine adsorption experiment, record the data, and conduct an adsorption stability test.

[0032] The results showed that the needle-like aldehyde porphyrin covalent organic framework material exhibited excellent gaseous iodine adsorption performance within 24 hours, with an adsorption capacity of 5.58 g / g. After 72 hours of adsorption, the adsorption capacity reached 5.98 g / g, making it an ideal gaseous iodine adsorbent. Figure 9 ).

[0033] In addition, the needle-like aldehyde porphyrin covalent organic framework material exhibits excellent iodine adsorption cycle stability, maintaining 84.21% iodine adsorption capacity after 5 adsorption-desorption cycles. Figure 10 ).

[0034] Although the present invention has been described in detail with reference to the accompanying drawings and preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention.

Claims

1. A mild method for preparing a needle-like aldehyde porphyrin covalent organic framework material, characterized in that, Includes the following steps: (1) Disperse the ligand 2',5'-bis((ethio)methyl)-[1,1':4',1''-terphenyl]-4,4''-diamine in acetonitrile solution to obtain solution A; (2) Dissolve tetraaldehyde phenylporphyrin in dichloromethane to obtain solution B; (3) Mix solution A and solution B; then slowly add ferric chloride acetonitrile solution and acetic acid, react under mild conditions, wash and dry to obtain needle-shaped aldehyde porphyrin covalent organic framework.

2. The mild preparation method according to claim 1, characterized in that, In step (1), the concentration of 2',5'-bis((ethio)methyl)-[1,1':4',1''-terphenyl]-4,4''-diamine in solution A is 0.5~1.0 g / L.

3. The mild preparation method according to claim 1, characterized in that, In step (2), the concentration of tetraaldehyde phenylporphyrin in solution B is 0.4~0.6 g / L.

4. The mild preparation method according to any one of claims 1-3, characterized in that, In step (3), the volume ratio of solution A to solution B is 0.8~1.2:

1.

5. The preparation method according to claim 1 or 4, characterized in that, In step (3), the concentration of the ferric chloride acetonitrile solution is 50 g / L; based on solution B, the amount of ferric chloride acetonitrile solution added to every 2.0 mL of solution B is 0.46~0.77 mmol, and the amount of acetic acid added is 5.25~10.50 mmol.

6. The mild preparation method according to any one of claims 1-5, characterized in that, In step (3), the reaction is carried out at a temperature of 50~80℃ for 2~6 hours with stirring.

7. A needle-shaped aldehyde porphyrin covalent organic framework material prepared by the preparation method according to any one of claims 1-6.

8. The application of the needle-shaped aldehyde porphyrin covalent organic framework material as described in claim 7 as a gaseous iodine adsorbent.

9. The application according to claim 8, characterized in that, The needle-shaped aldehyde porphyrin covalent organic framework material is used for the adsorption of gaseous iodine in the field of radioactive waste recycling.

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