Synthesis method and application of high-efficiency iodine adsorption material

Abstract

This invention belongs to the field of iodine adsorption material technology, and discloses a method for synthesizing and applying a highly efficient iodine adsorption material. The synthesis method includes: S1, adding an organic aldehyde ligand to a container, adding a solvent, and stirring to completely dissolve the aldehyde ligand; S2, slowly adding the above solution dropwise to an organic amine ligand solution to completely mix it with the amine ligand; S3, sealing the above mixed solution and stirring at room temperature until the color deepens; S4, after the reaction is complete, separating the reaction solution into small glass vials, tightening the caps, loosening them by half a turn, and placing them in a protective atmosphere; after several days of gas-liquid diffusion, visible crystals form at the bottom of the glass vials. The synthesized adsorption material has applications in volatile and radioactive iodine. The crystalline adsorption material synthesized by this invention has good stability, high adsorption efficiency for iodine, and a fast adsorption rate, and can be used for nuclear waste treatment and the capture of radioactive iodine.

Description

Technical Field

[0001] This invention relates to the field of iodine adsorption materials technology, specifically to a method for synthesizing and applying a highly efficient iodine adsorption material. Background Technology

[0002] Nuclear energy is one of the most promising clean energy sources for humanity's future. However, limitations in spent nuclear fuel reprocessing and improper handling of radioactive nuclide waste hinder its further sustainable development. Among these, volatile and radioactive iodine isotopes (such as...) 129 I and 131 I) Due to its dangerous effects of radioactivity, chemical and biological toxicity, it has attracted great attention from environmental and safety perspectives.

[0003] Porous covalent cages (PCCs) are cage-like organic molecules with a three-dimensional spatial structure formed by covalent bonds of light elements such as C, H, O, N, and B. These materials have broad application prospects in adsorption separation, energy storage, sensing, catalysis, and pollutant capture due to their advantages such as rigid framework structure, durable shape, tunable pore structure, large specific surface area, good thermal / chemical stability, and ease of post-modification. For example, metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and porous organic polymers (POPs) can all effectively capture iodine; however, finding iodine capture materials with directly visualized interactions remains extremely challenging. Summary of the Invention

[0004] This invention aims to provide a method for synthesizing and applying a highly efficient iodine adsorbent material, yielding a crystalline adsorbent material with good stability, high iodine adsorption efficiency, and fast adsorption rate. This material can be used for nuclear waste treatment, radioactive iodine capture, etc., thus solving the problems in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for synthesizing a highly efficient iodine adsorbent material, characterized by comprising the following steps:

[0007] S1. Add the organic aldehyde ligand to the container, add solvent, and stir to completely dissolve the aldehyde ligand;

[0008] S2. Slowly add the solution prepared in S1 to the organic amine ligand solution and stir until it is completely mixed with the amine ligand;

[0009] S3. Seal the mixed solution prepared in S2 and stir it at room temperature until the color darkens;

[0010] S4. After the solution in S3 has reacted completely, the reaction solution is transferred to a small glass bottle, the cap is tightened and then loosened by half a turn. The bottle is placed in a protective atmosphere for gas-liquid diffusion. Visible crystals form at the bottom of the glass bottle, thus synthesizing the iodine adsorbent material.

[0011] Furthermore, in S1, the aldehyde ligand is a bidentate, tridentate, tetradentate or other toothed organic compound based on an aromatic or aliphatic parent nucleus, and such aldehyde ligands have a planar or stereostructure.

[0012] Furthermore, in S2, the amino ligand is a bidentate, tridentate, tetradentate or other toothed organic compound based on an aliphatic or aromatic core; and such amino ligands have a planar or stereostructure.

[0013] Furthermore, in S2, the molar ratio of aldehyde ligand to amino ligand is 0.8 to 1.5:1.

[0014] Furthermore, in S1, the solvent is a polar organic solvent.

[0015] Furthermore, in S2, the solvent for the amino ligand is a polar organic solvent, and the addition time is 5 minutes.

[0016] Furthermore, in S3, the sealed mixture was stirred at 298 K for 8 hours.

[0017] Furthermore, in S4, equal volumes of haloaromatic hydrocarbons and acetonitrile were added to a glass vial containing the reaction solution, and the mixture was subjected to gas-liquid diffusion in an acetonitrile atmosphere for 15 days. The resulting crystals were yellow-green regular blocks.

[0018] Furthermore, in S1, the solvent is a low-polarity organic solvent.

[0019] Furthermore, in S2, the solvent for the amine ligand solution is a low-polarity organic solvent, and the addition time is 10 minutes.

[0020] Furthermore, in S3, the sealed mixed solution was stirred at 298K for 3 hours, and the color of the mixed solution changed from orange-yellow to fluorescent green and the solution became turbid.

[0021] Furthermore, in S4, a glass vial containing the reaction solution was subjected to gas-liquid diffusion in an ether atmosphere for 3 days to synthesize crystals that appeared as yellow-green clusters.

[0022] The above-mentioned method for synthesizing a highly efficient iodine adsorbent material has been applied to volatile and radioactive iodine. The adsorption of iodide ions or iodine molecules by the adsorbent material includes physical adsorption and chemical adsorption. Iodide ions form various effective hydrogen bonds and other weak forces near the framework of the adsorbent material.

[0023] The beneficial effects of the technical solution are:

[0024] 1. The synthesized adsorbent material has a rich pore structure and a large specific surface area, providing more active sites for the adsorption of iodine molecules; the functional groups such as amino and aldehyde groups in the adsorbent material can form stable interactions with iodine molecules, resulting in high adsorption efficiency and capacity of iodine.

[0025] 2. The solvents used in the synthesis process can be recycled and reused during the preparation process, reducing environmental pollution and waste; moreover, the preparation process is simple and easy to operate, without the need for harmful catalysts or additives, which is in line with the concept of green chemistry.

[0026] 3. During the synthesis process, the reaction is uniform, and the product has good crystallinity and stability; moreover, the bulk crystals are slowly obtained in a protective atmosphere through gas-liquid diffusion, which makes the material structurally stable and has strong adsorption properties.

[0027] 4. The synthesized adsorbent material exhibits both physical and chemical adsorption of iodine (ions or molecules); among which, the iodine adsorbed on the material is primarily composed of polyiodide ions (I3). - I5 - Or I7 - The iodine species, located near the material's framework, can form various effective hydrogen bonds and other weak interactions. Adsorbed iodine species can be directly observed using X-ray single-crystal diffraction. The adsorption rate is relatively fast, generally reaching saturation within 10 minutes. The adsorption capacity is substantial, typically 4-6 g / g, with a maximum exceeding 7 g / g. This makes it valuable for treating iodine-containing wastewater and exhaust gases, demonstrating significant application value. Furthermore, this material can be used in nuclear waste treatment and radioactive iodine capture, providing strong support for nuclear safety and environmental protection. Attached Figure Description

[0028] Figure 1 This is a crystal diagram of the adsorbent material synthesized in Example 1 of the present invention;

[0029] Figure 2 The chemical reaction equation for synthesizing the adsorbent material in Example 1 of this invention is shown below.

[0030] Figure 3 This is a crystal diagram of the adsorbent material synthesized in Example 2 of the present invention. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments:

[0032] Example 1

[0033] 118 mg (0.20 mmol) of an organic aldehyde ligand (the aldehyde ligand was an aromatic bidentate organic compound) was added to a 100 mL round-bottom flask, followed by 30 mL of CHCl3 and stirring until completely dissolved. A solution of 38 mg (0.26 mmol) of tris(2-aminoethyl)amine (TREN) dissolved in 10 mL of CHCl3 was slowly added dropwise (approximately 5 minutes) to the stirred mixture. The mixture was then sealed and stirred at room temperature (298 K) for 8 hours until the color changed from orange-yellow to fluorescent green. After the reaction was complete, the reaction solution was divided into 40 5 mL glass vials, each containing 1 mL of chlorobenzene and 1 mL of acetonitrile. After mixing 3 mL of the solution, the vials were tightened, then loosened half a turn, and placed in an acetonitrile atmosphere for gas-liquid diffusion for 15 days. Finally, regular yellow-green blocky crystals formed at the bottom of the vials, which were the desired adsorbent material. The crystal diagram of the synthesized adsorbent material is shown below. Figure 1 As shown, the chemical formula for synthesizing this adsorbent material is as follows: Figure 2 As shown.

[0034] Example 2

[0035] 353 mg (0.60 mmol) of an organic aldehyde ligand (the aldehyde ligand is a tridentate organic compound based on an aliphatic core) was added to a 250 mL round-bottom flask, followed by the addition of 100 mL of CH₂Cl₂ and stirring until dissolved. A solution of 114 mg (0.78 mmol) of tris(2-aminoethyl)amine (TREN) dissolved in 20 mL of CH₂Cl₂ was slowly added dropwise (over approximately 10 minutes) to the stirred mixture. The mixture was then sealed and stirred at room temperature (298 K) for 3 hours until the color changed from orange-yellow to fluorescent green and the solution became turbid. After the reaction was complete, the reaction solution was evenly divided into 60 5 mL glass vials, the caps were tightened and loosened by half a turn, and the vials were placed in an ether atmosphere for gas-liquid diffusion for 3 days. A large number of yellow-green clusters of crystals formed at the bottom of the vials, which is the desired adsorbent material. The crystal diagram of the synthesized adsorbent material is shown below. Figure 3 As shown.

[0036] Example 3

[0037] When the adsorbent material crystals are placed in an environment of 101.325 kPa and 273-373 K and iodine vapor is introduced, after a period of time, the adsorption saturation is reached, and the crystal color can be observed to turn into an opaque black.

[0038] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific technical solutions or characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for synthesizing a high-efficiency iodine adsorbent material, characterized in that, Includes the following steps: S1. Add the organic aldehyde ligand to the container, add solvent, and stir to completely dissolve the aldehyde ligand; S2. Slowly add the solution prepared in S1 to the organic amine ligand solution and stir until it is completely mixed with the amine ligand; S3. Seal the mixed solution prepared in S2 and stir it at room temperature until the color darkens; S4. After the solution in S3 has reacted completely, the reaction solution is transferred to a small glass bottle, the cap is tightened and then loosened by half a turn. The bottle is placed in a protective atmosphere. After the gas and liquid diffuse for several days, visible crystals form at the bottom of the glass bottle, thus synthesizing the iodine adsorbent material. In S1, the aldehyde ligand is a dipentate, tridentate, tetradentate or other toothed organic compound based on an aromatic or aliphatic parent nucleus. These aldehyde ligands have a planar or stereostructure. In S2, the amino ligand is a dipentate, tridentate, tetradentate or other toothed organic compound based on an aliphatic or aromatic core. These amino ligands have a planar or stereostructure. In S2, the molar ratio of aldehyde ligand to amino ligand is 0.8–1.5:1; In S4, equal volumes of haloaromatic hydrocarbons and acetonitrile are added to a glass vial containing the reaction solution, and the mixture is subjected to gas-liquid diffusion in an acetonitrile atmosphere for 15 days. The resulting crystals are yellow-green and regularly shaped blocks. Alternatively, in S4, a glass vial containing the reaction solution is subjected to gas-liquid diffusion in an ether atmosphere for 3 days. The resulting crystals are yellow-green and clustered.

2. The method for synthesizing a high-efficiency iodine adsorbent material according to claim 1, characterized in that, In S1, the solvent is a polar organic solvent.

3. The method for synthesizing a high-efficiency iodine adsorbent material according to claim 2, characterized in that, In S2, the solvent for the amine ligand is a polar organic solvent, and the addition time is 5 minutes.

4. The method for synthesizing a high-efficiency iodine adsorbent material according to claim 3, characterized in that, In S3, the sealed mixture was stirred at 298 K for 8 hours.

5. The method for synthesizing a high-efficiency iodine adsorbent material according to claim 1, characterized in that, In S1, the solvent is a low-polarity organic solvent.

6. The method for synthesizing a high-efficiency iodine adsorbent material according to claim 5, characterized in that, In S2, the solvent for the amine ligand solution is a low-polarity organic solvent, and the addition time is 10 minutes.

7. The method for synthesizing a high-efficiency iodine adsorbent material according to claim 6, characterized in that, In S3, the sealed mixed solution was stirred at 298 K for 3 hours, and the color of the mixed solution changed from orange-yellow to fluorescent green and the solution became turbid.

8. The application of the adsorbent material synthesized by the method for synthesizing a high-efficiency iodine adsorbent according to any one of claims 1 to 7 in the treatment of volatile and radioactive iodine, characterized in that, The adsorption of iodide ions or iodine molecules by adsorbent materials includes physical adsorption and chemical adsorption; iodide ions form various effective hydrogen bonds and other weak forces near the framework of the adsorbent material.

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