Method for extracting uranium from seawater based on radiation and metal organic framework material
By combining radiation technology with metal-organic frameworks (MOFs), the problems of low uranium extraction depth, long cycle and poor selectivity in seawater uranium extraction have been solved, achieving efficient and rapid uranium enrichment and extraction, which is suitable for large-scale applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SUZHOU UNIV
- Filing Date
- 2026-06-22
- Publication Date
- 2026-07-21
AI Technical Summary
In existing seawater uranium extraction technologies, traditional adsorption materials have low uranium extraction depth, long adsorption cycle, and poor selectivity and stability. Photocatalysis requires the addition of small organic molecule sacrificial agents, and the reaction products interfere with uranium reduction, making it difficult to extract uranium efficiently under natural light. The combination of radiation technology and MOF materials has not yet formed a mature system.
By combining radiation technology with metal-organic frameworks (MOFs), the ordered porous structure of MOFs is used to sensitize radiation effects, enabling the rapid extraction of ultra-low concentration uranium from seawater. MOFs, as radiation sensitizers, do not require the addition of auxiliary agents, thus improving energy utilization efficiency and efficiently enriching uranium.
This method efficiently enriches uranium from natural seawater in a short time, possessing advantages such as fast uranium extraction rate, high enrichment capacity, excellent spatiotemporal efficiency, and scalability. The material's morphology, crystal structure, and chemical functional groups remain stable after irradiation, making it suitable for large-scale seawater uranium extraction.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of seawater uranium extraction technology, and particularly relates to a seawater uranium extraction method based on radiation and metal-organic framework materials. Background Technology
[0002] Nuclear energy, as a clean and efficient energy source, occupies an increasingly important position in the global energy structure. Currently, nuclear fuel is mainly composed of uranium oxide, so the stable acquisition of uranium resources directly determines the sustainable development of the nuclear energy industry. Seawater contains abundant uranium resources. Although its uranium concentration is extremely low, due to the vast amount of seawater, the total uranium content is approximately 4.5 billion tons, more than 1,000 times the uranium reserves on land. Therefore, seawater uranium extraction has become an important way to solve the uranium resource shortage and ensure the development of the nuclear energy industry, attracting widespread attention from research fields both domestically and internationally.
[0003] Currently, seawater uranium extraction technologies have made some progress, mainly covering adsorption, electrochemical, photocatalytic, and radiation-assisted uranium extraction methods. Among these, adsorption is the current mainstream technology. Traditional adsorption mainly uses solid-liquid extraction, which is significantly affected by the complex system of seawater. Seawater not only has high salinity and abundant competing ions, but also contains a large number of microorganisms, which can hinder the adsorption of uranium by adsorbent materials and damage the structure of adsorbent materials due to seawater shear forces and biological activity, reducing material stability. In recent years, adsorbent materials modified with functional groups such as amylopectin groups using organic polymer fibers as carriers have become a research hotspot. Although such materials have made some progress, the adsorption process often takes tens of days due to the extremely low uranium concentration in seawater. Long-term exposure to the marine environment will further aggravate the loss of mechanical properties of the materials. At the same time, the adsorption of uranium by amylopectin groups is a kinetically controlled process, while the adsorption of competing ions such as vanadate in seawater is a thermodynamically controlled process. Excessive adsorption time will significantly reduce the adsorption selectivity of uranium. Furthermore, even when biomolecules with high stability constants are selected as adsorption materials, long cycles, low adsorption capacity, and poor material stability remain common shortcomings of adsorption methods, making it difficult to support the efficient and large-scale application of seawater uranium extraction.
[0004] While electrochemical methods can shorten uranium extraction time to some extent, the direct application of potential in high-salinity seawater conditions triggers numerous side reactions such as chlorine oxidation, significantly reducing uranium extraction efficiency. Furthermore, limitations in electrode size hinder large-scale production and make this method unsuitable for the demands of large-scale uranium extraction from natural seawater. Photocatalytic methods generally require the addition of small organic molecule sacrificial agents, increasing extraction costs and making batch operations difficult. Additionally, the peroxide and hydroxyl radicals generated during the reaction can impede uranium reduction. Moreover, most photocatalytic materials cannot effectively extract uranium from seawater under natural light. Even with improved extraction time compared to traditional adsorption methods, their efficiency still has significant room for improvement, making them unsuitable for practical applications.
[0005] Furthermore, all existing seawater uranium extraction technologies are constrained by the adsorption-desorption equilibrium. This core issue not only affects the kinetic rate and adsorption capacity of adsorption methods but also hinders further improvements in the efficiency of electrochemical and photocatalytic uranium extraction methods. Although radiation technology has shown some potential in seawater uranium extraction, and materials with ordered channels and high atomic numbers, such as MOFs, possess radiation-sensitized advantages, a mature seawater uranium extraction technology system combining radiation and MOFs materials has not yet been established. Existing technologies still cannot effectively solve the core challenges of high efficiency, stability, selectivity, and scalability in seawater uranium extraction.
[0006] Therefore, developing an efficient, rapid, and stable seawater uranium extraction technology has become a critical technical bottleneck that urgently needs to be addressed in this field, and is of great significance for promoting the independent development of the nuclear energy industry. Summary of the Invention
[0007] Therefore, the technical problem to be solved by the present invention is to overcome the defects of traditional adsorption materials in existing seawater uranium extraction technology, such as low uranium extraction depth, long adsorption cycle, poor selectivity and stability, as well as the problems of photocatalysis requiring the addition of small organic molecule sacrificial agents, the generation of peroxide and hydroxyl radicals interfering with uranium reduction, and the difficulty in efficiently extracting uranium under natural light.
[0008] To address the aforementioned technical problems, this invention provides a seawater uranium extraction method based on radiation and metal-organic frameworks (MOFs). This method combines radiation technology with MOFs, utilizing the ordered porous structure of MOFs to efficiently sensitize radiation effects. This allows for the rapid extraction of ultra-low concentration uranium from seawater without the need for any additives. As a radiation sensitizer, MOFs significantly improve the energy utilization efficiency of the seawater uranium extraction process, enabling efficient enrichment of uranium from natural seawater in a short time. It possesses advantages such as fast uranium extraction rate, high enrichment capacity, excellent spatiotemporal efficiency, and scalability.
[0009] The purpose of this invention is to provide a method for uranium extraction from seawater based on radiation and metal-organic framework materials, comprising the following steps: placing the metal-organic framework material in a uranium-containing solution and irradiating it to obtain a uranium-containing product.
[0010] In one embodiment of the present invention, the metal-organic framework material is selected from one or more of UiO-66, UiO-67 and MOF-808.
[0011] In one embodiment of the present invention, the metal-organic framework material is selected from UiO-66 and / or MOF-808.
[0012] In one embodiment of the present invention, the amount of metal-organic framework material added is 0.2 g / L-0.3 g / L.
[0013] In one embodiment of the present invention, the metal-organic framework material can be recycled more than four times after separation and washing.
[0014] In one embodiment of the present invention, the concentration of uranium in the uranium-containing solution is 3 ppb-8000 ppb.
[0015] In one embodiment of the invention, the irradiation source is selected from one or more of gamma rays, electron beams, and X-rays.
[0016] In one embodiment of the present invention, the γ-ray is 60 Co γ-ray source.
[0017] In one embodiment of the present invention, the irradiation dose is 5kGy-20kGy.
[0018] In one embodiment of the present invention, the solid produced after irradiation is further filtered and washed to obtain uranium-containing products.
[0019] The technical solution of the present invention has the following advantages compared with the prior art: The method described in this invention utilizes the coupling of radiation technology and metal-organic framework materials to achieve uranium extraction from seawater. The radiation source used has a high energy density and can directly interact with the water-containing seawater system to generate highly reactive species. The strongly reducing hydrated electrons can efficiently reduce the highly mobile hexavalent uranium in seawater to the less mobile tetravalent uranium. The reduced and fixed tetravalent uranium is deposited in the pores of the metal-organic framework material, thereby achieving efficient enrichment and extraction of uranium. At the same time, the metal nodes of the metal-organic framework material are constructed using high atomic number metal elements, which can effectively deposit radiation energy. Combined with the radiation sensitization effect generated by the ordered porous structure of the material itself, the radiation utilization rate in the process of uranium extraction from seawater is significantly improved. Finally, high spatiotemporal efficiency extraction of uranium from natural seawater can be achieved without the addition of sacrificial agents and other additives. Attached Figure Description
[0020] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein: Figure 1 These are morphological images of MOF-808 before and after irradiation in seawater in Test Example 1 of this invention; Figure 2 The powder diffraction patterns of MOF-808 before and after irradiation in seawater in Test Example 1 of this invention; Figure 3 Solid-state NMR spectra of MOF-808 before and after irradiation in seawater in Test Example 1 of this invention. 13 C spectrum; Figure 4The infrared absorption spectra of MOF-808 before and after irradiation in seawater in Test Example 1 of this invention are shown. Figure 5 The theoretical pore size and uranium extraction performance of different Zr-based materials under γ-ray irradiation in Test Example 2 of this invention are shown in the figure below. The left figure is a comparison of the theoretical pore size of different Zr-based materials, and the right figure is the uranium adsorption performance of different Zr-based materials under γ-ray irradiation. Figure 6 The extraction rate of uranium from simulated seawater by the material under different radiation doses in Test Example 3 of this invention; Figure 7 The extraction rate of uranium from uranium-added seawater by MOF-808 under different radiation doses in Test Example 3 of this invention; Figure 8 The extraction rate of uranium from natural seawater by MOF-808 under different radiation doses in Test Example 3 of this invention; Figure 9 This refers to the extraction rate of uranium from different uranium-containing solutions under different conditions in Test Example 3 of the present invention; Figure 10 The recycling performance of MOF-808 in Test Example 4 of this invention; Figure 11 This is a schematic diagram of the large-scale seawater uranium extraction experimental apparatus in Test Example 5 of the present invention; Figure 12 The test example 5 of this invention demonstrates the uranium extraction kinetics performance of MOF-808 on 20L of natural seawater. Detailed Implementation
[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. It should be understood that the specific embodiments are only used to explain the present invention, but the embodiments are not intended to limit the present invention.
[0022] In this invention, unless otherwise stated, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0023] In this invention, unless otherwise stated, the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0024] In this invention, unless otherwise specified, the experimental methods used in the embodiments of this invention are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.
[0025] Example 1
[0026] The seawater uranium extraction method based on radiation and metal-organic framework materials in this embodiment specifically includes the following steps: S1. Add 20 mL of a mixed solution of N,N-dimethylformamide and 20 mL of formic acid to a headspace vial, then add 0.5 mmol of trimesic acid and 0.5 mmol of zirconium chloride octahydrate. After sonicating the resulting mixture for 15 min, react it at 100 °C for 7 days. After the solid product precipitates, wash it with methanol. Then, use dichloromethane and n-propane to exchange the solid with solvent for 3 h. After the solvent is removed, transfer the solid to a reaction tube and heat it at 150 °C under vacuum to remove the residual solvent in the pores, thus obtaining MOF-808. S2. Soak 0.25g of MOF-808 in 1L of seawater, using... 60 Uranium can be extracted by irradiating a Co gamma-ray source with a dose of 20 kGy.
[0027] Example 2
[0028] The process is basically the same as in Example 1, except that MOF-808 is replaced with UiO-66. The preparation of MOF-808 specifically includes the following steps: 40.8 mL of N,N-dimethylformamide and 3.6 g of glacial acetic acid were added to a headspace vial, followed by 0.4 mmol of zirconium tetrachloride and 0.4 mmol of terephthalic acid. After sonication for 20 min, the mixture was reacted at 120 °C for 24 h. After the reaction was completed, the solid was centrifuged and washed three times each with N,N-dimethylformamide and methanol. The product was then transferred to a reaction tube and dried under vacuum at 90 °C to remove residual solvent from the pores, yielding UiO-66.
[0029] Comparative Example 1
[0030] The process is basically the same as in Example 1, except that MOF-808 is replaced with PCN-224, and its preparation specifically includes the following steps: A mixture of 40 mL N,N-dimethylformamide and 0.8 mL water was added to a reaction vessel, followed by 0.85 mmol zirconium tetrachloride and 50 mmol terephthalic acid. After the solid dissolved, 0.25 mmol tetra(4-carboxyphenyl)porphyrin was added, and the mixture was stirred for 20 min after dissolution. The mixture was then placed in an oven at 120 °C for 24 h. After the reaction was completed, the solid was separated by centrifugation. The solid was dried and placed in a solution of N,N-dimethylformamide containing 1.5 mL of 4 mol / L hydrochloric acid. The solution was heated and stirred at 120 °C for 12 h. The solid was then soaked in methanol and acetone for 48 h, with the solvent replaced every 8 h. After the solvent was removed, the solid was transferred to a reaction tube and dried under vacuum at 100 °C for 12 h to obtain PCN-224.
[0031] Comparative Example 2
[0032] The basic principle is the same as in Example 1, except that MOF-808 is replaced with nano ZrO2.
[0033] Test Example 1
[0034] Based on Example 1, MOF-808 was characterized before and after irradiation, and the results are as follows: Figures 1-4 As shown.
[0035] from Figure 1 It can be seen that the MOF-808 material still maintains a regular microstructure after irradiation, and the crystal particles do not show obvious breakage, agglomeration or structural collapse. The morphology is basically consistent with that before irradiation, indicating that the material has excellent morphological stability under seawater system and target radiation dose.
[0036] from Figure 2 It can be seen that the position and intensity of the characteristic diffraction peaks of MOF-808 after irradiation are basically consistent with those of the original material. There is no obvious disappearance, shift or appearance of new impurity peaks, indicating that its periodic crystal structure has not been damaged by irradiation and the crystal phase remains highly intact.
[0037] from Figure 3 It can be seen that the characteristic chemical shifts of the ligands of MOF-808 did not change significantly before and after irradiation, the ligand skeleton structure was stable, and no obvious degradation or chemical bond breakage occurred.
[0038] from Figure 4 It can be seen that the position and intensity of the characteristic functional group absorption peaks of MOF-808 did not change significantly after irradiation, and the coordination structure and chemical composition remained stable.
[0039] The above results indicate that MOF-808 maintains its morphology, crystal structure, ligand framework, and chemical functional groups intact after γ-ray irradiation in seawater, exhibiting excellent irradiation stability. It can serve as a highly efficient and stable adsorbent carrier for radiation-assisted seawater uranium extraction.
[0040] Test Example 2
[0041] Based on the examples and comparative examples, after irradiation, the solid and liquid phases were separated by filtration. The supernatant was taken and the concentration of residual uranium in the solution was quantitatively detected by ICP-MS. The uranium removal rate was calculated to evaluate the radiation-assisted seawater uranium extraction performance of different materials. The results are as follows: Figure 5 As shown. From Figure 5It can be seen that the pore size and Zr node density (content of high atomic number elements) of MOF materials have a key impact on the performance of uranium extraction from irradiated seawater. UiO-66 has a small pore size and a high node density, which can increase the concentration of hydrated electrons per unit pore, but the diffusion of uranyl ions is limited, resulting in a generally average uranium extraction capacity. PCN-224 has a large pore size, but the node density is too low, making it difficult to fully utilize the active reducing species generated by irradiation, resulting in poor uranium extraction performance. ZrO2 lacks ordered channels and a high specific surface area, resulting in weak synergistic effects of radiation sensitization and adsorption, and the worst uranium extraction effect. MOF-808, on the other hand, has a moderate pore size and a reasonable node density, which is conducive to the diffusion and transport of uranyl ions in the channels and can efficiently utilize the reducing active sites generated in situ by irradiation to achieve uranium enrichment and fixation. Its uranium removal rate is significantly higher than that of UiO-66, PCN-224 and ZrO2, showing the best performance of uranium extraction from irradiated seawater.
[0042] Test Example 3
[0043] Based on Example 1 and Comparative Example 2, MOF-808 or ZrO2 was mixed with different uranium-containing solutions (simulated seawater, uranium-added seawater, and natural seawater), and conventional adsorption experiments were conducted or the mixtures were placed in a controlled environment. 60 Irradiation was performed using a Co gamma-ray source. After adsorption or irradiation, the solid and liquid phases were separated by filtration. The supernatant was collected, and the concentration of residual uranium in the solution was quantitatively detected by ICP-MS. The uranium removal rate was calculated to evaluate the radiation-assisted seawater uranium extraction performance under different radiation doses, different uranium-containing solution systems, and different reaction conditions. The original uranium concentration in simulated seawater was 8000 ppb, the original uranium concentration in uranium-added seawater was 300 ppb, and the original uranium concentration in natural seawater was 3.3 ppb. The results are as follows: Figures 6-9 As shown.
[0044] from Figure 6 It can be seen that with the increase of radiation dose, the extraction rate of uranium from simulated seawater by both MOF-808 and ZrO2 gradually increases, and at the same dose, the extraction rate of MOF-808 is significantly higher than that of ZrO2, indicating that MOF-808 has a better ability to enrich uranium in simulated seawater under radiation assistance.
[0045] from Figure 7 It can be seen that in uranium-enriched seawater, the uranium extraction rate of MOF-808 continuously increases with increasing radiation dose, showing a good dose dependence, which verifies the positive effect of radiation enhancement on uranium extraction efficiency.
[0046] from Figure 8 It can be seen that even in natural seawater with extremely low uranium concentrations, MOF-808 can still achieve efficient uranium extraction with the aid of radiation. The extraction rate steadily increases with the increase of radiation dose, demonstrating excellent adaptability to actual seawater.
[0047] from Figure 9It can be seen that in the three systems of simulated seawater, uranium-added seawater and natural seawater, the uranium extraction efficiency of the MOF-808+ irradiated group is much higher than that of the non-MOF-808+ irradiated group and the MOF-808+ irradiated group, and is also higher than the sum of the efficiencies of the latter two groups. Meanwhile, the uranium extraction efficiency of ZrO2, which has the highest metal content, in irradiated seawater is much lower than that of MOF-808.
[0048] The above results show that the pore-confined structure of MOFs materials can produce a highly efficient sensitization effect to radiation, generate more reducing active species in situ, and significantly improve the efficiency of uranium extraction from seawater in synergy with adsorption. Moreover, MOF-808 has the best uranium extraction performance in different uranium-containing solution systems and under different radiation conditions.
[0049] Test Example 4
[0050] Based on Example 1, after irradiation, the MOF-808 material was filtered, thoroughly washed with deionized water, vacuum dried, and then recovered. Repeatability tests were conducted under the same seawater system, radiation dose, and reaction conditions as the initial experiment, completing four cycles. The single-cycle uranium enrichment capacity and cumulative enrichment capacity after each cycle were recorded. The results are as follows: Figure 10 As shown. By Figure 10 It can be seen that during the four consecutive cycles, the single-cycle uranium enrichment capacity of MOF-808 remained stable without significant decrease, and the cumulative enrichment capacity increased steadily and linearly with the number of cycles, without any performance degradation or failure. These results indicate that MOF-808 is structurally stable, not easily damaged, and does not easily lose active sites under the coupled environment of seawater and gamma-ray irradiation, possessing excellent recycling performance. It can be used multiple times for radiation-assisted seawater uranium extraction, significantly reducing material costs.
[0051] Test Example 5
[0052] Reference Figure 11 The large-scale seawater uranium extraction device shown places the reaction vessel in 60 Under a Co gamma-ray radiation field, 20 L of natural seawater was continuously pumped into the reaction vessel using a circulating pump. MOF-808 material was added to the system for irradiation experiments. After irradiation for different times, the mixture was removed and filtered. The residual uranium concentration in the filtrate was accurately determined using ICP-MS, and the uranium extraction rate was calculated to evaluate the radiation-assisted uranium extraction performance of MOF-808 under large-scale conditions. The results are as follows: Figure 12 As shown. From Figure 12It can be seen that the radiation-induced seawater uranium extraction system can quickly reach extraction equilibrium in just 1 hour, which is much shorter than the processing cycle of dozens of days for traditional adsorption methods. Moreover, the seawater uranium extraction efficiency per unit mass of MOF-808 material per unit time is significantly higher than that of other existing seawater uranium extraction materials. This fully demonstrates that the technology has an ultra-high uranium extraction rate and excellent spatiotemporal efficiency in large-scale natural seawater uranium extraction scenarios, and can meet the needs of large-scale and efficient seawater uranium extraction applications.
[0053] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A method for uranium extraction from seawater based on radiation and metal-organic framework materials, characterized in that, Includes the following steps: The metal-organic framework material was placed in a uranium-containing solution and irradiated to obtain uranium-containing products.
2. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 1, characterized in that, The metal-organic framework material is selected from one or more of UiO-66, UiO-67 and MOF-808.
3. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 2, characterized in that, The metal-organic framework material is selected from UiO-66 and / or MOF-808.
4. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 1, characterized in that, The amount of the metal-organic framework material added is 0.2 g / L-0.3 g / L.
5. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 1, characterized in that, The metal-organic framework material can be recycled more than four times after separation and washing.
6. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 1, characterized in that, The concentration of uranium in the uranium-containing solution is 3 ppb-8000 ppb.
7. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 1, characterized in that, The irradiation source is selected from one or more of gamma rays, electron beams, and X-rays.
8. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 7, characterized in that, The gamma rays are 60 Co γ-ray source.
9. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 1, characterized in that, The irradiation dose is 5kGy-20kGy.
10. The seawater uranium extraction method based on radiation and metal-organic framework materials according to claim 1, characterized in that, It also includes filtering and washing the solids produced after irradiation to obtain uranium-containing products.