Water-soluble nitrogen-containing actinide cluster material, preparation method and application thereof
The method of preparing water-soluble nitrogen-containing actinide cluster materials by azole melting solves the problems of high equipment requirements, solvent evaporation pollution and single coordination mode in the synthesis of actinide clusters, and realizes low-cost, green and environmentally friendly synthesis of actinide clusters and high-efficiency catalytic effect.
Patent Information
- Application Number
- CN202410748883.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-12
- Publication Date
- 2025-10-17
- Estimated Expiration
- 2044-06-12
AI Technical Summary
Existing methods for synthesizing actinide clusters suffer from problems such as high equipment requirements, solvent volatilization pollution risks, limited coordination modes, high synthesis costs, and high energy consumption, making it difficult to meet the requirements for safety, greenness, and diversity.
The azole melting method uses azole ligands as the melting medium to react with tetravalent actinide nitrates, thereby constructing water-soluble nitrogen-containing actinide cluster materials at low temperature through self-assembly. This method avoids the solvent molecule and equipment requirements of traditional methods and provides a rapid, simple, and low-cost synthetic route.
Rapid, simple, and low-cost synthesis of actinide clusters was achieved, with high yield and no byproducts. The synthesized clusters are water-soluble, structurally stable, and have a wide range of applications. They possess Lewis acid and nitrogen-containing sites and exhibit excellent catalytic performance as nanocatalysts for the reaction of carbon dioxide and epoxides.
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Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of actinide cluster materials, in particular to a water-soluble nitrogen-containing actinide cluster material, a preparation method thereof and application. BACKGROUND
[0002] There are various synthesis methods for nanoclusters, and the nanoclusters have strong designability. The cluster chemistry can reveal the relationship between the structure of a substance and the macroscopic properties of the substance. The synthesis and design of novel nanoclusters are of great significance in understanding the coordination chemistry of metal ions, grasping the structural change rule and developing aesthetic structures. Moreover, the nanoclusters have wide application prospects in the fields of photoelectric catalysis, organic small molecule catalysis, biological medicine, environmental protection and the like. The construction of novel actinide clusters is of great significance in grasping the migration and diffusion rule of actinide elements, retarding the migration and diffusion of the actinide elements in the environment and preventing the actinide elements from causing radioactive pollution. However, due to the 5f electrons, the actinide elements have richer coordination properties than traditional transition metals and lanthanide metals, so the construction of actinide clusters is more challenging. Therefore, the development of a novel synthesis method for actinide clusters has attracted widespread attention.
[0003] At present, the existing cluster synthesis methods include a solvent thermal synthesis method, a hydrothermal synthesis method, an electrochemical synthesis method, a layered diffusion method and a template method and the like. The solvent thermal synthesis method and the hydrothermal synthesis method usually utilize the self-assembly of metal ions and organic ligands in water or different organic solvents under a certain temperature and high pressure to construct clusters. The method has the advantages that many classic clusters can be synthesized by a relatively mild method, and the size and morphology of the clusters can be well controlled. However, the method has the disadvantages that the equipment pressure is relatively high, the production scale-up requires relatively high equipment, and too many solvents participating in the reaction may lead to the formation of clusters tending to classic stable structures, which is not conducive to the construction of some clusters with difficult coordination. The electrochemical method usually deposits metal on the surface of an electrode to construct clusters. The method has the advantage that the growth rate can be well controlled, but has the disadvantage that special electrochemical equipment and specific potentials are required, and the universality is poor. The layered diffusion method utilizes the diffusion of reactants between two different solvents to grow crystals. Specifically, there are two methods: one is the volatilization diffusion of a large bottle surrounding a small bottle, and the other is to create a layered system by using different solvents in the same container such as a test tube. The solvents diffuse into each other at the interface to grow cluster crystals. The method has the advantages that the equipment requirement is simple, the energy consumption is low at room temperature, and the applicability is wide. However, the method also has the disadvantages of long growth period, slow speed, many influencing factors and unstable crystal quality. The template method usually utilizes some template agents or some existing porous structures as templates for cluster growth. The method has the advantage that the clusters with specific structures can be easily obtained, but also has the disadvantages that the preparation of some templates needs complicated procedures, the post-processing procedures are relatively complex, and impurities are often involved.
[0004] Due to the nature of radioactivity and toxicity of actinides, there is a high risk of pressure in the synthesis of actinide clusters by traditional hydrothermal and solvothermal methods, and the expensive special equipment of electrochemical method is not suitable for the synthesis of actinide clusters. As a common method for synthesizing actinide clusters, although the diffusion method plays an important role in improving the number of metal nuclei, it is not conducive to the improvement of coordination diversity because of the single metal coordination mode. In addition, some systems need to use organic solvents which are easy to produce radioactive pollution once volatilized. As a popular synthesis method in recent years, solvent-free method has been widely used because of its green and environmental protection, especially for the synthesis of actinide materials. Among them, the borate melt method is commonly used for the synthesis of actinide and super uranium complexes. However, on the one hand, the synthesis temperature required by the method is generally higher than 200 DEG C, which has high energy consumption. On the other hand, the crystals constructed by the system are mostly conventional complexes, and clusters are rarely present. Therefore, in view of safety, green and pollution-free, and coordination structure diversity, it is urgent to develop a new synthesis method of actinide crystals, especially actinide clusters. SUMMARY
[0005] To solve the above technical problems, the purpose of the present application is to provide a water-soluble nitrogen-containing actinide cluster material, its preparation method and application, mainly to provide a new type of actinide cluster preparation method based on nitrogen azole melting method, which is not only fast and simple, but also low in cost, high in yield and clean and green. The synthesized clusters can be well dissolved in water, and the reactants are simple without other by-products. The water-soluble nitrogen-containing actinide cluster material prepared has important significance for mastering the migration rule of radionuclides in nuclear waste.
[0006] The above purpose of the present application is realized by the following technical scheme:
[0007] The first aspect of the present application provides a preparation method of a water-soluble nitrogen-containing actinide cluster material, comprising the following steps: mixing a nitrogen azole ligand and a tetravalent actinide nitrate, heating to a temperature higher than the melting point of the nitrogen azole ligand by 1-50 DEG C, so that the nitrogen azole ligand is in a molten state, and the water-soluble nitrogen-containing actinide cluster material is obtained by reaction.
[0008] According to the hard-soft acid-base theory, actinides are more suitable for ligands containing carboxylic acid than nitrogen-containing ligands. Therefore, it is almost impossible for nitrogen-containing ligands to self-assemble to construct supramolecular structures with actinide ions alone. However, the method for preparing a water-soluble nitrogen-containing actinide cluster material by using a nitrogen azole ligand melting method in the present application avoids the large number of solvent molecules in the hydrothermal and solvothermal synthesis methods. The nitrogen azole ligand is used as a melting medium, so that the ligand concentration is high, the coordination opportunity with actinide ions is improved, and the nitrogen-containing actinide nanocluster is self-assembled under the condition of ligand melting. This provides a simple and effective idea and method for constructing actinide structures by using pure nitrogen-containing ligands, which is expected to be expanded to the synthesis of other materials which are difficult to coordinate with actinide elements.
[0009] The preparation method of the water-soluble nitrogen-containing actinide cluster material provided by the application is not only fast and simple, has mild conditions, low cost, large yield, is clean and green, has low requirements for equipment, can effectively avoid volatile pollution generated by the solvent method, and can well dissolve the synthesized cluster in water, and has simple reactants and no other by-products.
[0010] Further, the azole ligand is triazole or tetrazole, preferably triazole.
[0011] Further, the triazole is preferably 1,2,4-triazole (Htrz).
[0012] Further, when the azole ligand is triazole, the temperature is higher than the melting point of triazole by 10-30 DEG C.
[0013] Further, the tetravalent actinide nitrate is selected from one or more of thorium nitrate (Th(NO3)4), neptunium nitrate (Np(NO3)4) and plutonium nitrate (Pu(NO3)4).
[0014] Further, the molar ratio of the azole ligand to the tetravalent actinide nitrate is (10-20):1.
[0015] Further, the azole ligand and the tetravalent actinide nitrate are mixed and placed in a container, and the reaction is carried out in a sealed state.
[0016] Further, the container can be a vial.
[0017] Further, the reaction time is 1-7 days.
[0018] Further, after the reaction is completed, the steps of cleaning and drying are further included.
[0019] The second aspect of the application provides a water-soluble nitrogen-containing actinide cluster material prepared by the method of the first aspect.
[0020] The water-soluble nitrogen-containing actinide cluster material provided by the application has stable structure and wide application range.
[0021] The third aspect of the application provides an application of the water-soluble nitrogen-containing actinide cluster material of the second aspect as a nano catalyst.
[0022] The water-soluble nitrogen-containing actinide cluster material provided by the application can effectively fix carbon dioxide due to the Lewis acid and nitrogen-containing sites, and has excellent catalytic effect on the reaction of carbon dioxide and epoxide as a nano catalyst.
[0023] The application has the following beneficial effects:
[0024] (1) The method for preparing the water-soluble nitrogen-containing actinide cluster material by adopting the nitrogen azole ligand melting method avoids the solvent molecules existing in the hydrothermal and solvothermal synthesis methods, uses the nitrogen azole ligand as a melting medium, the ligand concentration is high, the coordination opportunity with the actinide ion is improved, the nitrogen-containing actinide nanocluster is self-assembled and constructed under the ligand melting condition, a simple and effective idea and method for constructing the actinide structure by using the pure nitrogen-containing ligand are provided, and the method is expected to be expanded to the synthesis of other materials which are difficult to coordinate with the actinide elements.
[0025] (2) The preparation method of the water-soluble nitrogen-containing actinide cluster material provided by the application is fast, simple, mild, low in cost, high in yield, clean and green, low in equipment requirement, can effectively avoid the volatile pollution generated by the solvent method, the synthesized cluster can be well dissolved in water, the reactants are simple, and there is no other by-product.
[0026] (3) The water-soluble nitrogen-containing actinide cluster material provided by the application is stable in structure and wide in application range, can effectively fix carbon dioxide due to the Lewis acid and nitrogen-containing sites, and has excellent catalytic effect on the reaction of carbon dioxide and epoxide as a nanometer catalyst. BRIEF DESCRIPTION OF DRAWINGS
[0027] Figure 1 The synthesis schematic diagram of the water-soluble nitrogen-containing actinide cluster material prepared in Example 1.
[0028] Figure 2 The powder diffraction comparison diagram of the water-soluble nitrogen-containing actinide cluster material prepared in Example 1 and the simulation.
[0029] Figure 3 The transmission electron microscope diagram of the water-soluble nitrogen-containing thorium cluster material prepared in Example 1.
[0030] Figure 4 The schematic diagram of the water-soluble nitrogen-containing thorium cluster material prepared in Example 1 as a nanometer catalyst for catalyzing the reaction of carbon dioxide and epoxide. DETAILED DESCRIPTION
[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this description, the singular forms "a", "an" and "the" include plural references unless the context clearly dictates otherwise. The term "and / or" includes any and all combinations of one or more of the associated listed items.
[0032] The application will be further described below in conjunction with the drawings and specific embodiments, so that those skilled in the art can better understand the application and implement it. However, the embodiments are not intended to limit the application.
[0033] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the materials and reagents used are all commercially available unless otherwise specified.
[0034] Example 1
[0035] A preparation method of a water-soluble nitrogen-containing thorium cluster material (ThC-1) comprises the following steps: placing 15 mmol of 1,2,4-triazole and 1 mmol of thorium nitrate in a cillin bottle, mixing the mixture, capping the cel, and heating the mixture in an oven at 140°C until the 1,2,4-triazole is in a molten state; reacting the mixture for 1 day, cooling the mixture to room temperature, washing the mixture with methanol, and drying the mixture to obtain a water-soluble nitrogen-containing thorium cluster material ([Th6O4(OH)4(Htrz)7(trz)(NO3) 10 (H2O)]·(NO3)·3(Htrz)·5(H2O), ThC-1).
[0036] Figure 1 Schematic diagram of the synthesis of the water-soluble nitrogen-containing thorium cluster material prepared in Example 1, as shown in FIG. Figure 1 As shown, molten triazole reacts with thorium nitrate at 140° C. to self-assemble and construct nitrogen-containing thorium clusters (ThC). The enlarged part is a schematic structural diagram of the thorium cluster constructed in the present invention.
[0037] Figure 2 The comparison diagram of the water-soluble nitrogen-containing thorium cluster material prepared in Example 1 and the simulated powder diffraction is as follows: Figure 2 As shown, the powder diffraction pattern of the synthetic material of Example 1 is compared with the powder diffraction pattern of the simulated nitrogen-containing thorium cluster material (ThC-1). The diffraction peaks of the synthetic material and the simulated pattern correspond one to one, proving that the cluster structure is successfully synthesized and has high purity.
[0038] Figure 3 This is a transmission electron micrograph of the water-soluble nitrogen-containing thorium cluster material prepared in Example 1. The water-soluble nitrogen-containing thorium cluster material after being dissolved in water was characterized using a transmission electron microscope. Figure 3 As shown, the water-soluble nitrogen-containing thorium cluster material prepared by the present invention is nano-scale and does not decompose in water.
[0039] Example 2
[0040] A method for preparing a water-soluble nitrogen-containing thorium cluster material (ThC-1) comprises the following steps: placing 15 mmol of 1,2,4-triazole and 1 mmol of thorium nitrate in a cillin bottle, mixing the mixture, capping the mixture, and heating the mixture in an oven at 140° C. until the 1,2,4-triazole is in a molten state; reacting the mixture for 7 days, cooling the mixture to room temperature, washing the mixture with methanol, and drying the mixture to obtain the water-soluble nitrogen-containing thorium cluster material.
[0041] Example 3
[0042] A method for preparing a water-soluble nitrogen-containing thorium cluster material (ThC-1) includes the following steps: 10 mmol of 1,2,4-triazole and 1 mmol of thorium nitrate are mixed in a flask, the flask is capped and then placed in an oven at 140°C to heat the 1,2,4-triazole to a molten state, the reaction is allowed to proceed for 1 day, and then the mixture is cooled to room temperature, washed with methanol, and dried to obtain the water-soluble nitrogen-containing thorium cluster material.
[0043] Example 4
[0044] A method for preparing a water-soluble nitrogen-containing thorium cluster material (ThC-1) includes the following steps: 20 mmol of 1,2,4-triazole and 1 mmol of thorium nitrate are mixed in a flask, the flask is capped and then placed in an oven at 140°C to heat the 1,2,4-triazole to a molten state, the reaction is allowed to proceed for 1 day, and then the mixture is cooled to room temperature, washed with methanol, and dried to obtain the water-soluble nitrogen-containing thorium cluster material.
[0045] Example 5
[0046] A method for preparing a water-soluble nitrogen-containing thorium cluster material (ThC-1) includes the following steps: 20 mmol of 1H-tetrazole and 1 mmol of thorium nitrate are mixed in a flask, the flask is capped and then placed in an oven at 160°C to heat the 1H-tetrazole to a molten state, the reaction is allowed to proceed for 1 day, and then the mixture is cooled to room temperature, washed with methanol, and dried to obtain the water-soluble nitrogen-containing thorium cluster material.
[0047] The powder diffraction pattern of the water-soluble nitrogen-containing thorium cluster material prepared in Examples 2-5 is substantially the same as the powder diffraction pattern of Example 1, proving that the water-soluble nitrogen-containing thorium cluster material has been successfully prepared.
[0048] Example 6
[0049] A method for preparing a water-soluble nitrogen-containing thorium cluster material (ThC-1) includes the following steps: 10 mmol of 1,2,4-triazole and 1 mmol of thorium nitrate are mixed in a flask, the flask is capped and then placed in an oven at 140°C to heat the 1,2,4-triazole to a molten state, the reaction is allowed to proceed for 1 day, and then the mixture is cooled to room temperature, washed with methanol, and dried to obtain the water-soluble nitrogen-containing thorium cluster material.
[0050] Example 7
[0051] A preparation method of a water-soluble nitrogen-containing plutonium cluster material, comprising the following steps: 15 μmol 1,2,4-triazole and 1 μmol plutonium nitrate are mixed in a flask, after capping, they are placed in an oven at 140 ℃ to heat until the 1,2,4-triazole is in a molten state, after reaction for 1 day, they are cooled to room temperature, washed with methanol and dried to obtain the water-soluble nitrogen-containing plutonium cluster material, and it is proved by characterization that the water-soluble nitrogen-containing plutonium cluster material is successfully prepared.
[0052] Comparative Example 1
[0053] 10 mmol 1,2,4-triazole and 1 mmol thorium chloride are mixed in a flask, after capping, they are placed in an oven at 140 ℃ to heat until the 1,2,4-triazole is in a molten state, after reaction for 7 days, they are cooled to room temperature, and there are still solid particles (thorium chloride), and no crystals are generated, indicating that no nitrogen-containing thorium cluster material is generated.
[0054] Comparative Example 2
[0055] 10 mmol 1,2,4-triazole and 1 mmol thorium acetate are mixed in a flask, after capping, they are placed in an oven at 140 ℃ to heat until the 1,2,4-triazole is in a molten state, after reaction for 7 days, they are cooled to room temperature, and there are still solid particles (thorium acetate), and no crystals are generated, indicating that no nitrogen-containing thorium cluster material is generated.
[0056] Comparative Example 3
[0057] 10 mmol 1,2,4-triazole and 1 mmol thorium nitrate are mixed in a flask, after capping, they are placed in an oven at 180 ℃ to heat until the 1,2,4-triazole is in a molten state, after reaction for 1 day, the solution is cold yellow, and after cooling to room temperature, the solution becomes a solid, and no nitrogen-containing thorium cluster material is generated.
[0058] Comparative Example 4
[0059] 10 mmol 1,2,4-triazole and 1 mmol thorium nitrate are mixed in a flask, after capping, they are placed in an oven at 220 ℃ to heat until the 1,2,4-triazole is in a molten state, after reaction for 1 day, the solution is cold yellow, and after cooling to room temperature, the solution becomes a solid, and no nitrogen-containing thorium cluster material is generated.
[0060] Comparative Example 5
[0061] 10 mmol imidazole and 1 mmol thorium nitrate are mixed in a flask, after capping, they are placed in an oven at 140 ℃ to heat until the imidazole is in a molten state, after reaction for 1 day, there are still solid particles (thorium nitrate), and no crystals are generated, indicating that no nitrogen-containing thorium cluster material is generated.
[0062] Application Example 1
[0063] The water-soluble nitrogen-containing thorium cluster material prepared in Example 1 is used as a nanocatalyst to catalyze the reaction of carbon dioxide and epoxide, and a reaction schematic diagram is shown in Figure 4 The triazole (Htrz) and thorium (Th) can provide active sites for the reaction, and finally realize the fixation of carbon dioxide, and the specific experiment is as follows:
[0064] 2 mmol of styrene oxide, 0.025 mmol of tetrabutylammonium bromide and 0.01 mmol of the water-soluble nitrogen-containing thorium cluster material (ThC-1) prepared in Example 1 are added into a 10 mL glass vial, the vial is placed in a 1000 mL screw cap bottle, the screw cap bottle is filled with carbon dioxide for 10 minutes, the screw cap bottle is heated to 75℃, and the reaction is carried out for 24 h.
[0065] The reaction results prove that after adding the water-soluble nitrogen-containing thorium cluster material as a nanocatalyst, the reaction yield is increased by 10% to 20% compared with the reaction yield without adding the catalyst.
[0066] The preparation method of the water-soluble nitrogen-containing actinide cluster material provided by the application is not only fast and simple, mild in conditions, low in cost, large in yield, clean and green, but also low in equipment requirement, can effectively avoid volatile pollution generated by the solvent method, the synthesized cluster can be well dissolved in water, and the reactants are simple and no other by-products are generated. The water-soluble nitrogen-containing actinide cluster material prepared by the application has stable structure and wide application range, can effectively fix carbon dioxide due to the Lewis acid and nitrogen-containing sites, and has excellent catalytic effect on the reaction of carbon dioxide and epoxide as a nanocatalyst.
[0067] Obviously, the above embodiments of the application are only examples for clearly illustrating the application, and are not intended to limit the implementation modes of the application. Those skilled in the art should understand that on the basis of the above description, other different forms of changes or variations can also be made. Here, all the implementation modes are not required or can not be exhausted. Any modification, equivalent replacement and improvement made within the spirit and principle of the application should be included in the protection scope of the claims of the application.
Claims
1. A method for preparing a water-soluble nitrogen-containing actinide cluster material, characterized in that: The following steps are involved: The azole ligand and the tetravalent actinide nitrate are mixed and heated to a temperature 1 to 50°C higher than the melting point of the azole ligand so that the azole ligand is in a molten state, and the water-soluble nitrogen-containing actinide cluster material is reacted; the tetravalent actinide nitrate is thorium nitrate; and the azole ligand is triazole.
2. The preparation method according to claim 1, wherein The temperature is 10-30° C. higher than the melting point of triazole.
3. The preparation method according to claim 1, characterized in that The molar ratio of the azole ligand to the tetravalent actinide nitrate is (10-20):
1.
4. The preparation method according to claim 1, characterized in that The nitrogen azole ligand and the tetravalent actinide nitrate are mixed and placed in a container, and reacted in a sealed state.
5. The preparation method according to claim 1, characterized in that The reaction time is 1 to 7 days.
6. The preparation method according to claim 1, characterized in that After the reaction is completed, the steps of washing and drying are also included.
7. A water-soluble nitrogen-containing actinide cluster material prepared by the method according to any one of claims 1 to 6.
8. Use of the water-soluble nitrogen-containing actinide cluster material according to claim 7 as a nanocatalyst, wherein the nanocatalyst is used to catalyze the reaction of carbon dioxide and epoxide.