Amidoxime modified iron / titanium bimetallic doped carbon electrode and preparation method and application thereof

Abstract

The invention relates to the technical field of electrochemical uranium extraction, in particular to an amidoxime modified iron / titanium bimetallic doped carbon electrode and a preparation method and application thereof. The preparation method comprises the following steps: mixing 2-aminoterephthalic acid, N, N-dimethylformamide, methanol, tetrabutyl titanate and acetic acid, and carrying out heat treatment to obtain Ti-MOF; the preparation method comprises the following steps: mixing Ti-MOF with water, then putting the mixture into a composite solution consisting of ferrous acetate, 1, 10-phenanthroline, ethanol and water for reaction, then sequentially carrying out carbonization reduction reaction and nitridation reaction, mixing the obtained Fe / TiOx / C with polyacrylonitrile, azodiisobutyronitrile and N, N-dimethylformamide for oil bath, adding hydroxylamine hydrochloride and sodium carbonate, carrying out amidoximation reaction, coating the obtained carbon material on a graphite felt, and carrying out drying, thereby obtaining the Ti-MOF / polyacrylonitrile composite material. And obtaining the electrode. According to the prepared electrode, on the premise that a penetration type electrolytic cell is adopted, the uranium extraction rate can be increased to 90% only under the voltage of-0.9 V, and energy consumption is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of electrochemical uranium extraction technology, and in particular to a metallo-oxime modified iron / titanium bimetallic doped carbon electrode, its preparation method, and its application. Background Technology

[0002] Nuclear energy is a clean, efficient, and green energy source, and its development is conducive to promoting the transformation of the energy structure. Uranium is the main fuel for the nuclear energy industry, and the uranium content in seawater is about 1,000 times the total reserves of uranium mines on land, which is expected to provide abundant raw materials for the nuclear energy industry.

[0003] Currently, adsorption is the mainstream technology for uranium extraction from seawater. However, due to the low concentration of uranium in seawater, numerous competing ions, and severe biofouling, adsorption-based uranium extraction suffers from technical bottlenecks such as low efficiency and slow rate. Electrochemical uranium extraction technology can utilize an electric field to accelerate the migration and enrichment of uranium acyl ions in seawater towards electrode materials, and further convert uranium acyl ions into solid sediments through electrochemical reactions, facilitating product collection and purification. However, current electrochemical seawater uranium extraction technology relies on high operating voltages above -3V, leading to high energy consumption and costs, and easily triggering side reactions. The main reasons are: 1) a lack of high-performance electrode materials, requiring uranium deposition to overcome high reaction potential energy; and 2) low mass transfer efficiency in the reaction system, making it difficult for uranium acyl ions to contact the electrode surface. Furthermore, seawater contains a large amount of Na+. + It readily reacts with uranium in the form of Na x U y O z The co-deposition of uranium forms affects the purity of uranium products. Summary of the Invention

[0004] The purpose of this invention is to provide a metallo-oxime modified iron / titanium bimetallic doped carbon electrode, its preparation method and application. The electrode has a porous structure, which is conducive to the adsorption of uranyl ions, and the Fe and Ti bimetallic sites have strong catalytic activity, which can promote the electrodeposition efficiency of uranium.

[0005] To achieve the above objectives, the present invention provides a method for preparing a metallo-oxime modified iron / titanium bimetallic doped carbon electrode, comprising the following steps: S1. Mix 2-aminoterephthalic acid, N,N-dimethylformamide, methanol, and tetrabutyl titanate, and sonicate to obtain a suspension. Add acetic acid to the suspension and heat treat to obtain Ti-MOF. S2. Mix ferrous acetate, 1,10-phenanthroline, ethanol, and water to obtain a composite solution; S3. Mix Ti-MOF with water to obtain a Ti-MOF solution. Place the Ti-MOF solution in a composite solution and react to obtain an intermediate product. S4. Under an argon atmosphere, the intermediate product is subjected to a carbonization reduction reaction, followed by a nitriding reaction under an ammonia atmosphere. After cooling, Fe / TiO is obtained. x / C; S5, Fe / TiO x / C, polyacrylonitrile, azobisisobutyronitrile, and N,N-dimethylformamide are mixed and placed in an oil bath. The oil bath product is then dispersed in water, and hydroxylamine hydrochloride and sodium carbonate are added to carry out a geno-oxime reaction to obtain a geno-oxime modified iron / titanium bimetallic doped carbon material. S6. The amylopyrime-modified iron / titanium bimetallic doped carbon material is coated onto graphite felt to obtain the amylopyrime-modified iron / titanium bimetallic doped carbon electrode.

[0006] In this invention, the specific mixing process described in S1 includes: adding 2-aminoterephthalic acid, N,N-dimethylformamide, and methanol into a beaker, stirring at a stirring rate of 600-700 rpm for 12-18 minutes at a temperature of 18-30°C, then adding tetrabutyl titanate, and sonicating for 10-20 minutes to obtain a suspension.

[0007] In this invention, the preferred mass-to-volume ratio of 2-aminoterephthalic acid, N,N-dimethylformamide, methanol, and tetrabutyl titanate in S1 is 0.1-1g:1-20mL:1-20mL:0.1-20mL, more preferably 0.3-0.6g:8-15mL:1-1.2mL:0.2-0.4mL, and even more preferably 0.54g:9mL:1.1mL:0.26mL; the preferred volume ratio of acetic acid to methanol is 0.01-1:1-20, more preferably 0.01-0.02:1-1.2, and even more preferably 0.015:1.1; the preferred heat treatment temperature is 50-240℃, more preferably 100-200℃, and even more preferably 150℃; the preferred heat treatment time is 6-72h, more preferably 10-20h, and even more preferably 15h.

[0008] In this invention, after the heat treatment in S1 is completed, the product obtained by heat treatment is washed by centrifugation with N,N-dimethylformamide, water and ethanol in sequence, and then dried under vacuum to obtain Ti-MOF.

[0009] In this invention, the preferred mass-to-volume ratio of ferrous acetate, 1,10-phenanthroline, ethanol, and water in S2 is 0.0050-1g:0.0200-1g:1-20mL:1-20mL, more preferably 0.0075-0.0080g:0.0225-0.0300g:2-5mL:5-8mL, and even more preferably 0.0075g:0.0225g:3mL:6mL.

[0010] In this invention, the mass-to-volume ratio of Ti-MOF to water in S3 is preferably 0.01-1g:1-20mL, more preferably 0.02-0.04g:8-12mL, and even more preferably 0.03g:10mL; the mass-to-volume ratio of Ti-MOF to the composite solution is preferably 0.01-1g:1-20mL, more preferably 0.02-0.04g:8-10mL, and even more preferably 0.03g:9mL; the reaction temperature is preferably 20-100℃, more preferably 90-100℃, and even more preferably 100℃; the reaction time is preferably 1-12h, more preferably 9-11h, and even more preferably 10h.

[0011] In this invention, after the reaction described in S3 is completed, the reaction system is subjected to rotary evaporation to obtain an intermediate product.

[0012] In this invention, the temperature of the carbonization reduction reaction in S4 is preferably 500-1000℃, more preferably 700-900℃, and even more preferably 800℃, and the time of the carbonization reduction reaction is preferably 0.1-2h, more preferably 1-1.5h, and even more preferably 1h; The preferred temperature for the nitriding reaction is 500-1000℃, more preferably 700-1000℃, and even more preferably 800℃. The preferred time for the nitriding reaction is 0.1-2h, more preferably 0.5-1.5h, and even more preferably 0.5h.

[0013] In this invention, the cooling process described in S4 includes: introducing argon gas into the system until the system temperature cools to room temperature, thereby obtaining Fe / TiO. x / C.

[0014] In this invention, the Fe / TiO3 in S5 x The preferred mass-to-volume ratio of Fe / TiO₂, polyacrylonitrile, azobisisobutyronitrile, and N,N-dimethylformamide is 25-35 mg: 10-25 mg: 0.3-0.8 mg: 25 mL, more preferably 28-32 mg: 12-18 mg: 0.4-0.7 mg: 25 mL, and even more preferably 30 mg: 15 mg: 0.5 mg: 25 mL; the preferred temperature of the oil bath is 115-125℃, more preferably 120℃, and the preferred oil bath time is 1-3 h, more preferably 2 h; xThe preferred mass-to-volume ratio of C, water, hydroxylamine hydrochloride, and sodium carbonate is 25-35 mg:30 mL:45-55 mg:70-80 mg, more preferably 28-32 mg:30 mL:48-52 mg:72-78 mg, and even more preferably 30 mg:30 mL:50 mg:75 mg; the preferred temperature for the amylopyroxylation reaction is 65-75°C, more preferably 70°C, and the preferred time for the amylopyroxylation reaction is 10-14 h, more preferably 12 h.

[0015] In this invention, the oil bath in step S5 is carried out under a protective atmosphere, which includes nitrogen. After the oil bath is completed, the reaction system is filtered to obtain the oil bath product.

[0016] In this invention, after the amylopyroxylation reaction described in S5 is completed, the reaction system is centrifuged, the precipitate is collected, washed sequentially with water and ethanol, and then placed in a vacuum drying oven and dried under vacuum at 55-65°C to obtain amylopyroxymethylene-modified iron / titanium bimetallic doped carbon material.

[0017] The present invention also provides a method for preparing the above-mentioned amygdoxime-modified iron / titanium bimetallic doped carbon electrode, which yields the amygdoxime-modified iron / titanium bimetallic doped carbon electrode.

[0018] This invention also provides the application of the above-mentioned amine oxime-modified iron / titanium bimetallic doped carbon electrode in electrochemical seawater uranium extraction.

[0019] This invention also provides a method for applying the above-mentioned amine oxime-modified iron / titanium bimetallic doped carbon electrode in electrochemical seawater uranium extraction, comprising the following steps: (1) Using the above-mentioned iron / titanium bimetallic doped carbon electrode modified with amine oxime as the cathode and a platinum sheet as the anode, the cathode and anode are assembled in a through-type electrolytic cell; (2) After adjusting the pH of the seawater to 2-7, it is introduced into the through-type electrolytic cell. The seawater first flows through the cathode and then through the anode before flowing out of the electrolytic cell. The input constant voltage of the cathode and anode is controlled to be -5~-0.5V to carry out electrochemical seawater uranium extraction.

[0020] In this invention, in step (2), the seawater is first settled and filtered, and then hydrochloric acid is added to adjust the pH of the seawater to 2-7.

[0021] In this invention, the method of introducing seawater in step (2) is to use a peristaltic pump to introduce seawater into the permeation electrolysis cell. The flow rate of the introduction is preferably 1-150 mL / min, more preferably 48 mL / min.

[0022] The present invention has the following beneficial effects: This invention provides a method for preparing a metallo-oxime-modified iron / titanium bimetallic doped carbon electrode, comprising the following steps: S1, mixing 2-aminoterephthalic acid, N,N-dimethylformamide, methanol, and tetrabutyl titanate, sonicating to obtain a suspension, adding acetic acid to the suspension for heat treatment to obtain Ti-MOF; S2, mixing ferrous acetate, 1,10-phenanthroline, ethanol, and water to obtain a composite solution; S3, mixing Ti-MOF with water to obtain a Ti-MOF solution, placing the Ti-MOF solution in the composite solution, reacting to obtain an intermediate product; S4, subjecting the intermediate product to a carbonization reduction reaction under an argon atmosphere, followed by a nitridation reaction under an ammonia atmosphere, cooling to obtain Fe / TiO2. x / C;S5, Fe / TiO x / C. Polyacrylonitrile, azobisisobutyronitrile, and N,N-dimethylformamide are mixed and placed in an oil bath. The oil bath product is then dispersed in water, and hydroxylamine hydrochloride and sodium carbonate are added to carry out a meramine oxime reaction to obtain a meramine oxime-modified iron / titanium bimetallic doped carbon material. S6. The meramine oxime-modified iron / titanium bimetallic doped carbon material is coated onto graphite felt to obtain a meramine oxime-modified iron / titanium bimetallic doped carbon electrode.

[0023] The metallo-amine oxime-modified iron / titanium bimetallic doped carbon electrode (Fe / TiO2) prepared in this invention x The / C-AO material possesses a porous structure, providing a large specific surface area, which is beneficial for adsorbing uranyl ions from seawater. The iron (Fe) and titanium (Ti) bimetallic sites in the material exhibit strong catalytic activity, effectively promoting the electrochemical deposition efficiency of uranium. The amine oxime groups modified on the material surface have a specific coordination effect on uranyl ions, further enhancing the uranium extraction performance.

[0024] This invention also provides a method for applying a metallo-oxime-modified iron / titanium bimetallic doped carbon electrode in electrochemical seawater uranium extraction, comprising the following steps: (1) Using the above-mentioned iron / titanium bimetallic doped carbon electrode modified with amine oxime as the cathode and a platinum sheet as the anode, the cathode and anode are assembled in a through-hole electrolytic cell; (2) After adjusting the pH of seawater to 2-7, it is introduced into the through-hole electrolytic cell. The seawater first flows through the cathode and then through the anode before flowing out of the electrolytic cell. The constant input voltage of the cathode and anode is controlled to be -5~-0.5V to carry out electrochemical seawater uranium extraction.

[0025] The present invention provides a method for applying a genoamine oxime-modified iron / titanium bimetallic doped carbon electrode in electrochemical seawater uranium extraction. The method employs a through-hole electrolyzer, in which seawater with a pH of 2-7 is introduced into the through-hole electrolyzer via a peristaltic pump, passing vertically through the electrode. A constant voltage of -5 to -0.5V is applied to the cathode and anode electrodes. After a certain reaction time, the solid product UO3·H2O can be collected from the electrode surface.

[0026] This invention employs a through-type electrolytic cell. When seawater passes through the electrodes, uranium is retained on the electrode surface due to its better affinity with the electrode material, while sodium... + It passes quickly with the water flow, so uranium and sodium... + There is insufficient time for co-deposition reactions to occur near the electrode; furthermore, adjusting the pH of the seawater to 2-7 also inhibits the co-deposition reaction. Therefore, this invention can directly collect high-purity UO3·H2O solid products from the electrode surface, simplifying subsequent secondary separation and purification steps.

[0027] This invention develops high-performance electrode materials and improves the mass transfer efficiency of the reactor (using a through-type electrolyzer), enabling the uranium extraction rate to be increased to 90% using an ultra-low voltage of -0.9 V, significantly improving uranium extraction efficiency while reducing energy consumption.

[0028] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the through-type electrolytic cell of the present invention; Figure 2 These are TEM and EDS test images of the amylopyridine-modified iron / titanium bimetallic doped carbon material prepared in Example 1 of this invention; in, Figure 2 (a) in the image is a TEM test image. Figure 2 (b) in the figure is the EDS test graph; Figure 3 These are the XRD diagrams of the final products of Application Examples 1 and 2 of this invention.

[0030] Figure label: 1. Water inlet; 2. Water inlet pipe; 3. Water outlet; 4. Anode chamber; 5. Fixing clamp; 6. Cathode. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments. Unless otherwise defined, the technical or scientific terms used in this invention should be understood in their ordinary sense by those skilled in the art. The features mentioned above or in the specific examples mentioned in this invention can be combined arbitrarily, and these specific embodiments are only used to illustrate the invention and are not intended to limit the scope of the invention.

[0032] Example 1 This embodiment provides a method for preparing a metallo-oxime modified iron / titanium bimetallic doped carbon electrode, comprising the following steps: S1. Add 0.54 g of 2-aminoterephthalic acid, 9 mL of N,N-dimethylformamide, and 1.1 mL of methanol to a beaker. Stir at 700 rpm for 15 min at 25 °C. Then add 0.26 mL of tetrabutyl titanate and sonicate for 15 min to obtain a suspension. Pour the suspension into a polytetrafluoroethylene-lined reactor and add 0.015 mL of acetic acid. Heat treat at 150 °C for 15 h. After the heat treatment is completed, wash the product obtained by centrifugation with N,N-dimethylformamide, water, and ethanol in sequence. After vacuum drying, obtain Ti-MOF. S2. Mix 0.0075 g of ferrous acetate, 0.0225 g of 1,10-phenanthroline, 3 mL of ethanol, and 6 mL of water to obtain a composite solution; S3. Mix 0.03 g of Ti-MOF with 10 mL of water to obtain a Ti-MOF solution. Place the Ti-MOF solution in 9 mL of a composite solution and react at 100 °C for 10 h. After the reaction is complete, the reaction system is rotary evaporated to obtain an intermediate product. S4. Place the intermediate product in a tube furnace, introduce argon gas, and perform a carbonization and reduction reaction at 800°C for 1 hour. After the carbonization and reduction reaction is completed, stop introducing argon gas and reintroduce ammonia gas. Perform a nitriding reaction at 800°C for 0.5 hours under an ammonia atmosphere. Then stop introducing ammonia gas and reintroduce argon gas until the system temperature cools to room temperature to obtain Fe / TiO₂. x / C; S5, Add 30mg of Fe / TiO₂ x A mixture of 15 mg of polyacrylonitrile, 0.5 mg of azobisisobutyronitrile, and 25 mL of N,N-dimethylformamide was prepared and heated in an oil bath at 120 °C for 2 h under a nitrogen atmosphere. After the oil bath was completed, the reaction system was filtered to obtain the oil bath product. The oil bath product was dispersed in 30 mL of water, and 50 mg of hydroxylamine hydrochloride and 75 mg of sodium carbonate were added. The mixture was subjected to a cycloximation reaction at 70 °C for 12 h. After the cycloximation reaction was completed, the reaction system was centrifuged, the precipitate was collected, washed successively with water and ethanol, and then placed in a vacuum drying oven and dried under vacuum at 60 °C to obtain a cycloximation-modified iron / titanium bimetallic doped carbon material. S6. The amylopyrime-modified iron / titanium bimetallic doped carbon material is coated onto graphite felt to obtain the amylopyrime-modified iron / titanium bimetallic doped carbon electrode.

[0033] Example 2 This embodiment provides a method for preparing a metallo-oxime modified iron / titanium bimetallic doped carbon electrode, comprising the following steps: S1. Add 0.6 g of 2-aminoterephthalic acid, 15 mL of N,N-dimethylformamide, and 1.2 mL of methanol to a beaker. Stir at 700 rpm for 15 min at 25 °C. Then add 0.4 mL of tetrabutyl titanate and sonicate for 15 min to obtain a suspension. Pour the suspension into a polytetrafluoroethylene-lined reactor and add 0.02 mL of acetic acid. Heat treat at 200 °C for 10 h. After the heat treatment is completed, wash the heat-treated product sequentially with N,N-dimethylformamide, water, and ethanol by centrifugation. After vacuum drying, obtain Ti-MOF. S2. Mix 0.0080 g of ferrous acetate, 0.0300 g of 1,10-phenanthroline, 5 mL of ethanol, and 8 mL of water to obtain a composite solution; S3. Mix 0.02 g of Ti-MOF with 8 mL of water to obtain a Ti-MOF solution. Place the Ti-MOF solution in 8 mL of the composite solution and react at 100 °C for 9 h. After the reaction is complete, the reaction system is rotary evaporated to obtain the intermediate product. S4. Place the intermediate product in a tube furnace, introduce argon gas, and perform a carbonization reduction reaction at 700°C for 2 hours. After the carbonization reduction reaction is completed, stop introducing argon gas and reintroduce ammonia gas. Perform a nitriding reaction at 700°C for 2 hours under an ammonia atmosphere. Then stop introducing ammonia gas and reintroduce argon gas until the system temperature cools to room temperature to obtain Fe / TiO₂. x / C; S5, Add 28mg of Fe / TiO₂ x A mixture of 12 mg of polyacrylonitrile, 0.4 mg of azobisisobutyronitrile, and 25 mL of N,N-dimethylformamide was prepared and heated in an oil bath at 125 °C for 3 h under a nitrogen atmosphere. After the oil bath was completed, the reaction system was filtered to obtain the oil bath product. The oil bath product was dispersed in 30 mL of water, and 48 mg of hydroxylamine hydrochloride and 72 mg of sodium carbonate were added. The mixture was subjected to a methylamine oxime reaction at 75 °C for 10 h. After the methylamine oxime reaction was completed, the reaction system was centrifuged, the precipitate was collected, washed successively with water and ethanol, and then placed in a vacuum drying oven and dried under vacuum at 60 °C to obtain a methylamine oxime-modified iron / titanium bimetallic doped carbon material. S6. The amylopyrime-modified iron / titanium bimetallic doped carbon material is coated onto graphite felt to obtain the amylopyrime-modified iron / titanium bimetallic doped carbon electrode.

[0034] Example 3 This embodiment provides a method for preparing a metallo-oxime modified iron / titanium bimetallic doped carbon electrode, comprising the following steps: S1. Add 0.3 g of 2-aminoterephthalic acid, 8 mL of N,N-dimethylformamide, and 1.1 mL of methanol to a beaker. Stir at 700 rpm for 15 min at 25 °C. Then add 0.2 mL of tetrabutyl titanate and sonicate for 15 min to obtain a suspension. Pour the suspension into a polytetrafluoroethylene-lined reactor and add 0.01 mL of acetic acid. Heat treat at 100 °C for 20 h. After the heat treatment is completed, wash the product obtained by centrifugation with N,N-dimethylformamide, water, and ethanol in sequence. After vacuum drying, obtain Ti-MOF. S2. Mix 0.0090 g of ferrous acetate, 0.0200 g of 1,10-phenanthroline, 2 mL of ethanol, and 5 mL of water to obtain a composite solution; S3. Mix 0.04 g of Ti-MOF with 12 mL of water to obtain a Ti-MOF solution. Place the Ti-MOF solution in 10 mL of the composite solution and react at 90 °C for 11 h. After the reaction is complete, the reaction system is rotary evaporated to obtain the intermediate product. S4. Place the intermediate product in a tube furnace, introduce argon gas, and perform a carbonization reduction reaction at 900℃ for 1.5 h. After the carbonization reduction reaction is completed, stop introducing argon gas and reintroduce ammonia gas. Perform a nitriding reaction at 1000℃ for 1.5 h under an ammonia atmosphere. Then stop introducing ammonia gas and reintroduce argon gas until the system temperature cools to room temperature to obtain Fe / TiO. x / C; S5, 32mg of Fe / TiO x A mixture of 18 mg of polyacrylonitrile, 0.7 mg of azobisisobutyronitrile, and 25 mL of N,N-dimethylformamide was prepared and heated in an oil bath at 115 °C for 1 h under a nitrogen atmosphere. After the oil bath was completed, the reaction system was filtered to obtain the oil bath product. The oil bath product was dispersed in 30 mL of water, and 52 mg of hydroxylamine hydrochloride and 78 mg of sodium carbonate were added. The mixture was subjected to a methylamine oxime reaction at 65 °C for 14 h. After the methylamine oxime reaction was completed, the reaction system was centrifuged, the precipitate was collected, washed successively with water and ethanol, and then placed in a vacuum drying oven and dried under vacuum at 60 °C to obtain a methylamine oxime-modified iron / titanium bimetallic doped carbon material. S6. The amylopyrime-modified iron / titanium bimetallic doped carbon material is coated onto graphite felt to obtain the amylopyrime-modified iron / titanium bimetallic doped carbon electrode.

[0035] Characterization tests: The TEM and EDS observations were performed on the amylopyridine-modified iron / titanium bimetallic doped carbon material prepared in Example 1, and the results are as follows: Figure 2 As shown. From Figure 2As can be seen from (a) in the present invention, the amylopyrime-modified iron / titanium bimetallic doped carbon material is nanoscale. Figure 2 As can be seen from (b) in this paper, the present invention has successfully prepared carbon-supported Fe / TiOx bimetallic materials, namely, a amine oxime-modified iron / titanium bimetallic doped carbon materials.

[0036] Application Example 1 The iron / titanium bimetallic doped carbon electrode modified with amine oxime prepared in Example 1 was assembled into a battery for electrochemical seawater uranium extraction. A schematic diagram of the through-hole electrolyzer structure is shown below. Figure 1 As shown. The process includes: (1) Using the iron / titanium bimetallic doped carbon electrode modified with amine oxime prepared in Example 1 as the cathode and a platinum sheet as the anode, the cathode 6 is fixed on the fixing clamp 5 of the through-type electrolytic cell, and the anode is placed in the anode chamber 4 of the through-type electrolytic cell to complete the assembly. (2) After the seawater is settled and filtered, hydrochloric acid is added to adjust the pH of the seawater to 6. Then, a peristaltic pump is used to push the seawater into the permeation electrolytic cell through the inlet pipe 2 at the water inlet 1 (the flow rate is 48 mL / min). The seawater first flows through the cathode 6 and then through the anode chamber 4 before flowing out from the outlet 3 of the permeation electrolytic cell. The input constant voltage of the cathode 6 and the anode is controlled to be -0.9V to carry out electrochemical seawater uranium extraction.

[0037] Application Example 2 (1) Using the iron / titanium bimetallic doped carbon electrode modified with amine oxime prepared in Example 1 as the cathode and a platinum sheet as the anode, the cathode 6 is fixed on the fixing clamp 5 of the through-type electrolytic cell, and the anode is placed in the anode chamber 4 of the through-type electrolytic cell to complete the assembly. (2) After the seawater is settled and filtered, the pH is not adjusted. The seawater (pH 7.8) is directly fed into the permeation electrolytic cell through the inlet pipe 2 at the water inlet 1 (the flow rate is 0.5 mL / min). The seawater first flows through the cathode 6 and then through the anode chamber 4 and then flows out from the outlet 3 of the permeation electrolytic cell. The input constant voltage of the cathode 6 and the anode is controlled to be -0.9V to carry out electrochemical seawater uranium extraction.

[0038] Performance testing: The final products obtained from the corresponding use case 1 and application example 2 were subjected to XRD testing, and the results are as follows: Figure 3 As shown.

[0039] Simultaneously, the extraction rate is calculated using the formula: .

[0040] from Figure 3It can be seen that the final product obtained is different under different conditions of seawater pH and different infusion rates. The product obtained in Example 1 is UO3·H2O, while the product obtained in Example 2 is Na2O(UO3·H2O). This is because seawater naturally contains a relatively large amount of Na. + When the seawater current is slow, the Na+ in the seawater... + With sufficient contact time with the uranium deposited on the electrode, a reaction easily occurs to form Na₂O (UO₃·H₂O); however, when the seawater flow rate is high, Na₂O... + Reducing the contact time with uranium can suppress co-deposition. On the other hand, seawater has a naturally alkaline pH of 7.8, with a relatively high concentration of OH-. - It can promote the formation of Na2O (UO3·H2O); conversely, when pH=6, H + Furthermore, it can suppress the formation of Na₂O (UO₃·H₂O). For these two reasons, using the conditions in Application Example 1 can prevent Na… + The co-deposition process results in a purer uranium product.

[0041] According to the formula, the uranium extraction rate in Application Example 1 was 90%, and the uranium extraction rate in Application Example 2 was 75%. Combining the final extraction rate and... Figure 3 XRD analysis of the product shows that the oxime-modified iron / titanium bimetallic doped carbon electrode provided by this invention, when used as the cathode for electrochemical seawater uranium extraction, requires only an ultra-low voltage of -0.9V to increase the uranium extraction rate to 90% under the premise of using a through-hole electrolyzer, which greatly improves the uranium extraction efficiency while reducing energy consumption.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a metallo-oxime modified iron / titanium bimetallic doped carbon electrode, characterized in that, Includes the following steps: S1. Mix 2-aminoterephthalic acid, N,N-dimethylformamide, methanol, and tetrabutyl titanate, and sonicate to obtain a suspension. Add acetic acid to the suspension and heat treat to obtain Ti-MOF. S2. Mix ferrous acetate, 1,10-phenanthroline, ethanol, and water to obtain a composite solution; S3. Mix Ti-MOF with water to obtain a Ti-MOF solution. Place the Ti-MOF solution in a composite solution and react to obtain an intermediate product. S4. Under an argon atmosphere, the intermediate product is subjected to a carbonization reduction reaction, followed by a nitridation reaction under an ammonia atmosphere. After cooling, Fe / TiO is obtained. x / C; S5, Fe / TiO x / C, polyacrylonitrile, azobisisobutyronitrile, and N,N-dimethylformamide are mixed and placed in an oil bath. The oil bath product is then dispersed in water, and hydroxylamine hydrochloride and sodium carbonate are added to carry out a geno-oxime reaction to obtain a geno-oxime modified iron / titanium bimetallic doped carbon material. S6. The amylopyrime-modified iron / titanium bimetallic doped carbon material is coated onto graphite felt to obtain the amylopyrime-modified iron / titanium bimetallic doped carbon electrode.

2. The method for preparing a metallo-oxime modified iron / titanium bimetallic doped carbon electrode according to claim 1, characterized in that, The mass-to-volume ratio of 2-aminoterephthalic acid, N,N-dimethylformamide, methanol, and tetrabutyl titanate in S1 is 0.1-1 g : 1-20 mL : 1-20 mL : 0.1-20 mL; the volume ratio of acetic acid to methanol is 0.01-1 : 1-20. The heat treatment temperature is 50-240℃, and the heat treatment time is 6-72h.

3. The method for preparing a metallo-oxime modified iron / titanium bimetallic doped carbon electrode according to claim 1, characterized in that, The mass-to-volume ratio of ferrous acetate, 1,10-phenanthroline, ethanol, and water in S2 is 0.0050-1g:0.0200-1g:1-20mL:1-20mL.

4. The method for preparing a geminal oxime-modified iron / titanium bimetallic doped carbon electrode according to claim 1, characterized in that, The mass-to-volume ratio of Ti-MOF to water in S3 is 0.01-1g:1-20mL, and the mass-to-volume ratio of Ti-MOF to the composite solution is 0.01-1g:1-20mL. The reaction temperature is 20-100℃, and the reaction time is 1-12h.

5. The method for preparing a metallo-oxime modified iron / titanium bimetallic doped carbon electrode according to claim 1, characterized in that, The carbonization-reduction reaction described in S4 is carried out at a temperature of 500-1000℃ for 0.1-2 hours. The nitriding reaction is carried out at a temperature of 500-1000℃ for a duration of 0.1-2 hours.

6. The method for preparing a geminal oxime-modified iron / titanium bimetallic doped carbon electrode according to claim 1, characterized in that, The Fe / TiO3 mentioned in S5 x The mass-to-volume ratio of C, polyacrylonitrile, azobisisobutyronitrile, and N,N-dimethylformamide is 25-35 mg: 10-25 mg: 0.3-0.8 mg: 25 mL, the oil bath temperature is 115-125℃, and the oil bath time is 1-3 h. The Fe / TiO x The mass-to-volume ratio of C, water, hydroxylamine hydrochloride, and sodium carbonate is 25-35 mg: 30 mL: 45-55 mg: 70-80 mg; The amylopyroxylation reaction is carried out at a temperature of 65-75°C for 10-14 hours.

7. A metallo-oxime-modified iron / titanium bimetallic doped carbon electrode prepared by the method for preparing a metallo-oxime-modified iron / titanium bimetallic doped carbon electrode according to any one of claims 1-6.

8. The application of the amine oxime-modified iron / titanium bimetallic doped carbon electrode according to claim 7 in electrochemical seawater uranium extraction.

9. The method for applying the geminal oxime-modified iron / titanium bimetallic doped carbon electrode of claim 8 in electrochemical seawater uranium extraction, characterized in that, Includes the following steps: (1) Using the iron / titanium bimetallic doped carbon electrode modified with amine oxime as described in claim 7 as the cathode and a platinum sheet as the anode, the cathode and anode are assembled in a through-type electrolytic cell; (2) After adjusting the pH of the seawater to 2-7, it is introduced into the through-type electrolytic cell. The seawater first flows through the cathode and then through the anode before flowing out of the electrolytic cell. The input constant voltage of the cathode and anode is controlled to be -5~-0.5V to carry out electrochemical seawater uranium extraction.

10. The method for applying the geminal oxime-modified iron / titanium bimetallic doped carbon electrode of claim 9 in electrochemical seawater uranium extraction, characterized in that, The flow rate introduced in step (2) is 1-150 mL / min.

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