Strontium nickel titanate electrode for removing uranium as well as preparation method and application of strontium nickel titanate electrode

Abstract

The invention relates to the technical field of water treatment and environmental governance, in particular to a strontium nickel titanate electrode for removing uranium and a preparation method and application thereof.The preparation method comprises the steps that a titanium source, an alcohol amine carrier and an alkaline solution are mixed, and a precursor solution is obtained; adding a nickel source and a strontium source into the precursor solution, and carrying out ultrasonic and hydrothermal reaction to obtain a strontium nickel titanate material; and coating the surface of the carbon fiber substrate material with the strontium nickel titanate material to obtain the strontium nickel titanate electrode without uranium. Through a combined process of nickel doping, hydrothermal reaction and carbon cloth substrate coating, the prepared electrode forms a porous and uniformly dispersed composite structure, and meanwhile, it is ensured that the electrode can have preferable selectivity and removal efficiency on uranium within the pH range of 3-9. The strontium nickel titanate electrode for removing uranium prepared by the invention is suitable for large-scale water treatment application, and especially has a good application prospect in the field of purification of nuclear wastewater and drinking water.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water treatment and environmental governance, in particular to a nickel strontium titanate electrode for removing uranium and a preparation method and application thereof. BACKGROUND

[0002] Uranium is a radioactive metal that exists widely in nature and is discharged in large quantities in industrial activities such as mineral exploitation and nuclear energy production. Due to its long half-life and strong radioactivity, the accumulation of uranium in water bodies can have a serious impact on the ecological environment and human health. Especially in the discharge of nuclear wastewater and the treatment of mine wastewater, the concentration of uranium often exceeds the environmental standard, causing long-term pollution of water sources. Existing uranium removal technologies, such as chemical precipitation, adsorption and reverse osmosis, can reduce the concentration of uranium to some extent, but these methods have low treatment efficiency, high cost, complex operation and may cause secondary pollution, etc., making it difficult to meet the challenges of large-scale and persistent pollution. Therefore, it is urgent to develop an efficient, low-cost and environmentally friendly uranium removal technology to meet the increasingly severe water pollution control needs.

[0003] In recent years, electrochemical removal technology has gradually become an effective means to solve water pollution problems due to its fast reaction speed, simple operation and low energy consumption. The choice of electrode material directly affects the efficiency of electrochemical removal. Currently, strontium titanate electrodes have been widely used in water treatment due to their good chemical stability and electrochemical performance. However, the cyclic stability of strontium titanate electrodes is poor and they are prone to activity decay during use, resulting in short service life and the need for frequent replacement, which increases operational costs and maintenance difficulties. Although some studies have attempted to enhance the performance of strontium titanate electrodes by doping transition metals, the type of doped transition metal, the doping ratio and the reaction conditions during the doping process can all cause changes in the active sites and structure of the strontium titanate electrode surface, thereby affecting the adsorption efficiency and stability of uranium.

[0004] Therefore, it is of great scientific value and has wide practical application prospects to develop an efficient and stable electrode suitable for the treatment of low-concentration uranium-polluted water bodies. SUMMARY

[0005] The purpose of the present application is to provide a nickel strontium titanate electrode for removing uranium and a preparation method and application thereof, in order to solve the problems of low removal efficiency, poor stability and short service life of existing electrode materials in the process of removing uranium.

[0006] To achieve the above-mentioned purpose, the present application provides a preparation method of a nickel strontium titanate electrode for removing uranium, comprising the following preparation steps: S1, mixing a titanium source, an alcohol amine carrier and an alkaline solution to obtain a precursor solution; S2, adding a nickel source and a strontium source to the precursor solution, ultrasonicating, and hydrothermally reacting to obtain a nickel strontium titanate material; S3, coating the nickel strontium titanate material on a surface of a carbon fiber base material to obtain a nickel strontium titanate electrode from which uranium is removed.

[0007] In the present application, the specific process of S1 includes: adding a titanium source to an alcohol amine carrier, and after stirring at a temperature of 60-70 DEG C for 2-3 h, adding a basic solution for mixing.

[0008] In the present application, the titanium source in S1 includes at least one of tetrabutyl titanate, acid tetraisopropyl titanate, and n-octyl titanate; the alcohol amine carrier includes at least one of ethanol amine, monoethanol amine, and propanol amine; the basic solution includes at least one of a sodium hydroxide solution, a potassium hydroxide solution, and ammonia water; and the concentration of the basic solution is 2-2.5 mol / L.

[0009] In the present application, the alcohol amine carrier is selected to provide a stable environment for introducing the nickel element during the reaction.

[0010] In the present application, the volume ratio of the titanium source, the alcohol amine carrier, and the basic solution in S1 is 2-4:20-30:40-60.

[0011] In the present application, the temperature for mixing in S1 is 60-70 DEG C, and the mixing time is 1-1.5 h.

[0012] In the present application, the nickel source in S2 is a nickel-containing salt solution with a concentration of 0.05-0.1 mol / L, and the strontium source is a strontium-containing salt solution with a concentration of 0.3-0.5 mol / L; the volume ratio of the nickel source, the strontium source, and the basic solution is 2-3:5-7:40-60.

[0013] In the present application, the nickel-containing salt solution includes at least one of a nickel chloride solution, a nickel nitrate solution, and a nickel sulfate solution, and the strontium-containing salt solution includes at least one of a strontium nitrate solution, a strontium chloride solution, and a strontium acetate solution.

[0014] In the present application, the ultrasonicating time in S2 is 4-6 h.

[0015] In the present application, the hydrothermal reaction temperature in S2 is 170-190 DEG C, and the hydrothermal reaction time is 20-30 h.

[0016] In the present application, after the hydrothermal reaction in S2 is completed, a hydrothermal reaction product is obtained, the hydrothermal reaction product is sequentially washed with hydrochloric acid and water, and then placed in a centrifuge for centrifugation at a centrifugal speed of 700-800 rpm for 30-50 min to obtain a centrifugal slurry; the centrifugal slurry is placed in a drying box for drying at a temperature of 70-90 DEG C for 10-12 h to obtain the nickel strontium titanate material.

[0017] In the present application, the carbon fiber base material in S3 includes at least one of carbon cloth electrode, carbon felt electrode, carbon paper electrode, and the thickness of the strontium nickel titanate material coating is 0.3-0.5mm.

[0018] The present application also provides a uranium-removed strontium nickel titanate electrode prepared by the preparation method of the uranium-removed strontium nickel titanate electrode.

[0019] The present application also provides the application of the uranium-removed strontium nickel titanate electrode in removing uranium in wastewater.

[0020] The present application has the following beneficial effects: The present application provides a preparation method of a uranium-removed strontium nickel titanate electrode, which comprises the following preparation steps: S1, mixing a titanium source, an alcohol amine carrier and an alkaline solution to obtain a precursor solution; S2, adding a nickel source and a strontium source to the precursor solution, ultrasonicating and hydrothermally reacting to obtain a strontium nickel titanate material; and S3, coating the strontium nickel titanate material on the surface of a carbon fiber base material to obtain a uranium-removed strontium nickel titanate electrode.

[0021] The present application forms a large number of active sites on the surface of the strontium titanate electrode by doping nickel metal, the electronic structure of the nickel ion has a strong interaction with the uranium ion, and the uranium ion can be specifically captured through complexation reaction, electrostatic adsorption and other modes, thereby improving the selective adsorption capacity for uranium.

[0022] The nickel doping not only increases the number of active sites, but also optimizes the electronic transmission characteristics of the electrode: the high stability of strontium titanate provides structural support for the electrode, and the high electrochemical activity of nickel accelerates electron transfer, so that the electrode response current reaches-3.95~-3.8mA. The high response current promotes the electrochemical reduction reaction of the uranium ion on the electrode surface, and significantly improves the removal efficiency.

[0023] The present application selects nickel metal doping, and nickel has certain acid and alkali resistance, is not easily protonated and corroded under acidic conditions, and will not form hydroxide precipitate under alkaline conditions. Strontium titanate has extremely strong chemical inertness and structural stability, a dense crystal structure and high chemical bond energy, and is not easy to hydrolyze or collapse under acidic or alkaline conditions. Therefore, the prepared uranium-removed strontium nickel titanate electrode always maintains adsorption and electrochemical reduction activity for uranium ions under the environment of pH 3-9.

[0024] The present application significantly reduces the charge transfer resistance of the electrode through the synergistic effect of nickel doping and the carbon fiber base material, ensures efficient and continuous performance of the steps of uranium ion adsorption, electron transfer and electrochemical reduction, avoids the problem of slow reaction kinetics caused by blocked electron transfer, and makes the uranium removal efficiency stable at 97%-99% within 6h.

[0025] The present application forms a porous and uniformly dispersed composite structure of the prepared uranium-removing nickel strontium titanate electrode through the combined process of nickel doping, hydrothermal reaction and carbon cloth coating; wherein the nickel doping introduces abundant metal active sites and optimizes the electrochemical performance, the hydrothermal reaction promotes the full formation of mesoporous / microporous structure, and the carbon cloth coating reduces the charge transfer resistance and stabilizes the active layer loading, the three synergistically expand the electrode electrochemical active area, shorten the uranium ion mass transfer distance, accelerate the combination of uranium ions and active sites and the electrochemical reaction process, and greatly improve the uranium selectivity and removal efficiency.

[0026] The preparation method provided by the present application selects low-cost raw materials, and has a simple preparation process and easy operation, and is suitable for large-scale production.

[0027] The present application further limits the temperature of the hydrothermal reaction in S2 to 170-190 DEG C, and the time of the hydrothermal reaction to 20-30 h, thereby improving the structural properties of the nickel strontium titanate by controlling the hydrothermal reaction conditions, forming a composite structure with high electrochemical activity and abundant metal ion sites, ensuring uniform dispersion of nickel ions in the strontium titanate lattice, and avoiding waste of active sites or uneven electrochemical performance caused by local agglomeration.

[0028] The uranium-removing nickel strontium titanate electrode prepared by the preparation method of the present application can efficiently remove uranium elements in wastewater, and the removal efficiency reaches more than 97% within a treatment time of 6 h. After 7 cycles, the removal efficiency still remains at 92%, and has excellent stability.

[0029] The uranium-removing nickel strontium titanate electrode prepared by the preparation method of the present application can still maintain a high removal efficiency in the pH range of 3-9, and can be widely applied to various scale water treatment systems, and has a significant market prospect and wide application potential.

[0030] The technical solutions of the present application are further described in detail below by means of the accompanying drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 is a response current test result graph of the uranium-removing nickel strontium titanate electrode prepared in Examples 1-3; Figure 2 is a response current test result graph of the strontium titanate electrode prepared in Comparative Example 1 and the nickel titanate electrode prepared in Comparative Example 2; Figure 3 is an electrochemical active area test result graph of the uranium-removing nickel strontium titanate electrode prepared in Examples 1-3; Figure 4 is an electrochemical active area test result graph of the strontium titanate electrode prepared in Comparative Example 1 and the nickel titanate electrode prepared in Comparative Example 2; Figure 5is a graph of the test results of the removal efficiency of uranium by the uranium-removing nickel strontium titanate electrode prepared in Example 1-3; Figure 6 is a graph of the test results of the removal efficiency of uranium by the strontium titanate electrode prepared in Comparative Example 1 and the nickel titanate electrode prepared in Comparative Example 2; Figure 7 is a graph of the test results of the removal efficiency of uranium by the uranium-removing nickel strontium titanate electrode prepared in Example 3 under different pH conditions; Figure 8 is a graph of the test results of the removal efficiency of uranium by the uranium-removing nickel strontium titanate electrode prepared in Example 3 after being cycled 7 times under the same conditions. DETAILED DESCRIPTION

[0032] The present application is further described below in conjunction with the accompanying drawings and examples. Unless otherwise defined, technical or scientific terms used in the present application should be understood as having the commonly understood meaning in the field of the present application to which the present application pertains. The features mentioned in the present application or the features mentioned in the specific examples mentioned above can be combined in any manner, and the specific examples are only used to illustrate the present application and not to limit the scope of the present application.

[0033] Example 1 A method for preparing a uranium-removing nickel strontium titanate electrode, comprising the following preparation steps: S1, 3 mL of tetrabutyl titanate is added to a beaker containing 30 mL of ethanolamine, stirred at a temperature of 60°C for 3 h, then 40 mL of a sodium hydroxide solution with a concentration of 2.2 mol / L is added, the temperature is kept unchanged, and mixed for 1.5 h to obtain a precursor solution; S2, 2.5 mL of a nickel chloride solution with a concentration of 0.1 mol / L and 6 mL of a strontium nitrate solution with a concentration of 0.5 mol / L are added to the above-mentioned precursor solution, ultrasonic treatment is performed for 5 h to obtain a mixed solution, and then the mixed solution is placed in a polytetrafluoroethylene reaction kettle, hydrothermal reaction is performed at a temperature of 170°C for 30 h to obtain a hydrothermal reaction product, the hydrothermal reaction product is sequentially washed with hydrochloric acid and water, then placed in a centrifuge, centrifuged at a centrifugal speed of 700 rpm for 50 min to obtain a centrifugal slurry, and the centrifugal slurry is placed in a drying box, dried at a temperature of 90°C for 10 h to obtain a nickel strontium titanate material; S3, the nickel strontium titanate material is coated on the surface of a carbon cloth electrode with a coating thickness of 0.3 mm to obtain a uranium-removing nickel strontium titanate electrode, which is denoted as NiSrTiO3-1.

[0034] Example 2 A method for preparing a uranium-removing nickel strontium titanate electrode, comprising the following preparation steps: S1, 4mL of tetrabutyl titanate was added to a beaker containing 25mL of ethanolamine, stirred at a temperature of 70℃ for 2.5h, then 60mL of sodium hydroxide solution with a concentration of 2mol / L was added, the temperature was kept unchanged, mixed for 1h, to obtain a precursor solution; S2, 2mL of nickel chloride solution with a concentration of 0.05mol / L and 5mL of strontium nitrate solution with a concentration of 0.4mol / L were added to the above-mentioned precursor solution, ultrasonic for 4h, to obtain a mixed solution, then the mixed solution was placed in a polytetrafluoroethylene reaction kettle, hydrothermal reaction was carried out at a temperature of 180℃ for 20h, to obtain a hydrothermal reaction product, the hydrothermal reaction product was sequentially washed with hydrochloric acid and water, then was placed in a centrifuge, centrifuged at a centrifugal speed of 750rpm for 30min, to obtain a centrifugal slurry, the centrifugal slurry was placed in a drying box, dried at a temperature of 80℃ for 12h, to obtain a nickel strontium titanate material; S3, the nickel strontium titanate material was coated on the surface of a carbon cloth electrode, the coating thickness was 0.4mm, to obtain a uranium-removed nickel strontium titanate electrode, recorded as NiSrTiO3-2.

[0035] Example 3 A preparation method of a uranium-removed nickel strontium titanate electrode, comprising the following preparation steps: S1, 2mL of tetrabutyl titanate was added to a beaker containing 20mL of ethanolamine, stirred at a temperature of 65℃ for 2h, then 50mL of sodium hydroxide solution with a concentration of 2.5mol / L was added, the temperature was kept unchanged, mixed for 1.2h, to obtain a precursor solution; S2, 3mL of nickel chloride solution with a concentration of 0.075mol / L and 7mL of strontium nitrate solution with a concentration of 0.3mol / L were added to the above-mentioned precursor solution, ultrasonic for 6h, to obtain a mixed solution, then the mixed solution was placed in a polytetrafluoroethylene reaction kettle, hydrothermal reaction was carried out at a temperature of 190℃ for 25h, to obtain a hydrothermal reaction product, the hydrothermal reaction product was sequentially washed with hydrochloric acid and water, then was placed in a centrifuge, centrifuged at a centrifugal speed of 800rpm for 40min, to obtain a centrifugal slurry, the centrifugal slurry was placed in a drying box, dried at a temperature of 70℃ for 11h, to obtain a nickel strontium titanate material; S3, the nickel strontium titanate material was coated on the surface of a carbon cloth electrode, the coating thickness was 0.5mm, to obtain a uranium-removed nickel strontium titanate electrode, recorded as NiSrTiO3-3.

[0036] Comparative Example 1 A preparation method of a strontium titanate electrode, comprising the following preparation steps: S1, 2mL of tetrabutyl titanate was added to a beaker containing 20mL of ethanolamine, stirred at a temperature of 65℃ for 2h, then 50mL of sodium hydroxide solution with a concentration of 2.5mol / L was added, the temperature was kept unchanged, mixed for 1.2h, to obtain a precursor solution; S2, 7 mL of a strontium nitrate solution with a concentration of 0.3 mol / L was added to the precursor solution, and ultrasonic treatment was performed for 6 h to obtain a mixed solution. Subsequently, the mixed solution was placed in a polytetrafluoroethylene reaction kettle, and hydrothermal reaction was performed at a temperature of 190 °C for 25 h to obtain a hydrothermal reaction product. After the hydrothermal reaction product was sequentially washed with hydrochloric acid and water, it was placed in a centrifuge, and centrifugation was performed at a centrifugal speed of 800 rpm for 40 min to obtain a centrifugal slurry. The centrifugal slurry was placed in a drying box, and drying was performed at a temperature of 70 °C for 11 h to obtain a strontium titanate material; S3, the strontium titanate material was coated on the surface of a carbon cloth electrode with a coating thickness of 0.5 mm to obtain a strontium titanate electrode from which uranium was removed, denoted as SrTiO3.

[0037] Comparative Example 2 A preparation method of a nickel titanate electrode includes the following preparation steps: S1, 2 mL of tetrabutyl titanate was added to a beaker containing 20 mL of ethanolamine, and stirring was performed at a temperature of 65 °C for 2 h. Subsequently, 50 mL of a sodium hydroxide solution with a concentration of 2.5 mol / L was added, and the temperature was maintained. Mixing was performed for 1.2 h to obtain a precursor solution; S2, 3 mL of a nickel chloride solution with a concentration of 0.75 mol / L was added to the precursor solution, and ultrasonic treatment was performed for 6 h to obtain a mixed solution. Subsequently, the mixed solution was placed in a polytetrafluoroethylene reaction kettle, and hydrothermal reaction was performed at a temperature of 190 °C for 25 h to obtain a hydrothermal reaction product. After the hydrothermal reaction product was sequentially washed with hydrochloric acid and water, it was placed in a centrifuge, and centrifugation was performed at a centrifugal speed of 800 rpm for 40 min to obtain a centrifugal slurry. The centrifugal slurry was placed in a drying box, and drying was performed at a temperature of 70 °C for 11 h to obtain a nickel titanate material; S3, the nickel titanate material was coated on the surface of a carbon cloth electrode with a coating thickness of 0.5 mm to obtain a nickel titanate electrode from which uranium was removed, denoted as NiTiO3.

[0038] Performance test: The response current of the nickel titanate electrode from which uranium was removed prepared in Example 1-3 was tested by an electrochemical workstation, and the results are shown in Figure 1 From Figure 1 it can be seen that the response current of NiSrTiO3-1 prepared in Example 1 was -3.85 mA, the response current of NiSrTiO3-2 prepared in Example 2 was -3.81 mA, and the response current of NiSrTiO3-3 prepared in Example 3 was -3.95 mA.

[0039] The response current of the strontium titanate electrode prepared in Comparative Example 1 and the nickel titanate electrode prepared in Comparative Example 2 was tested by an electrochemical workstation, and the results are shown in Figure 2 From Figure 2It can be seen that the response current of SrTiO3 prepared in Comparative Example 1 is -1.32 mA, and the response current of NiTiO3 prepared in Comparative Example 2 is -1.05 mA.

[0040] The electrochemical active area of ​​the uranium-removing strontium nickel titanate electrodes prepared in Examples 1-3 was tested using an electrochemical workstation, and the results are as follows: Figure 3 As shown. From Figure 3 It can be seen that the electrochemically active area of ​​NiSrTiO3-1 prepared in Example 1 is 109 cm⁻¹. 2 The electrochemically active area of ​​NiSrTiO3- prepared in Example 2 is 114 cm². 2 The electrochemically active area of ​​NiSrTiO3-3 prepared in Example 3 is 122 cm². 2 .

[0041] The electrochemical active areas of the strontium titanate electrode prepared in Comparative Example 1 and the nickel titanate electrode prepared in Comparative Example 2 were measured using an electrochemical workstation. The results are as follows: Figure 4 As shown. From Figure 4 It can be seen that the electrochemically active area of ​​SrTiO3 prepared in Comparative Example 1 is 46 cm². 2 The electrochemically active area of ​​NiTiO3 prepared in Comparative Example 2 was 34 cm². 2 .

[0042] Using the uranium-removed strontium nickel titanate electrode prepared in Examples 1-3 as the anode and a titanium sheet as the cathode, respectively, they were placed in 200 mL of a mixed solution containing coexisting ions (the mixed solution included: uranium ions, chloride ions, nitrate ions, bicarbonate ions, sodium ions, potassium ions, and magnesium ions, with each ion concentration of 10 mg / L and the pH of the mixed solution being 5). A current density of 5 mA / cm² was applied. 2 The uranium removal effect was tested at an experimental temperature of 25℃, and the results are as follows: Figure 5 As shown.

[0043] from Figure 5 It can be seen that the NiSrTiO3-1 prepared in Example 1 achieved a uranium removal efficiency of 98.2% within 6 hours, the NiSrTiO3-2 prepared in Example 2 achieved a uranium removal efficiency of 99.1% within 6 hours, and the NiSrTiO3-3 prepared in Example 3 achieved a uranium removal efficiency of 99.8% within 6 hours. This confirms that the strontium nickel titanate electrode for uranium removal prepared in this invention has excellent selectivity and high removal efficiency for uranium.

[0044] The titanium oxide electrode prepared in Comparative Example 1 and the titanium oxide electrode prepared in Comparative Example 2 were used as an anode, and a titanium sheet was used as a cathode, and then the electrodes were placed in 200 mL of a mixed solution containing coexisting ions (the mixed solution included: uranium ions, chloride ions, nitrate ions, bicarbonate ions, sodium ions, potassium ions, and magnesium ions, and the concentration of each ion was 10 mg / L, and the pH of the mixed solution was 5). The uranium removal effect was tested under the condition that the current density was 5 mA / cm 2 , and the experimental temperature was 25°C, and the results are shown in Figure 6 .

[0045] As can be seen from Figure 6 , the uranium removal rate of the SrTiO3 prepared in Comparative Example 1 was 60.5% within 6 h, and the uranium removal rate of the NiTiO3 prepared in Comparative Example 2 was 37.6% within 6 h, which were significantly lower than the uranium removal efficiency of the nickel strontium titanate electrode prepared by the preparation method of the present application.

[0046] The uranium removal nickel strontium titanate electrode prepared in Example 3 was used as an anode, and a titanium sheet was used as a cathode, and then the electrodes were placed in 200 mL of a mixed solution containing coexisting ions (the mixed solution included: uranium ions, chloride ions, nitrate ions, bicarbonate ions, sodium ions, potassium ions, and magnesium ions, and the concentration of each ion was 10 mg / L, and the pH of the mixed solution was 5) with different pH (pH was 3, 4, 5, 6, 7, 8, 9). The uranium removal effect was tested under the condition that the current density was 5 mA / cm 2 , and the experimental temperature was 25°C, and the results are shown in Figure 7 . As can be seen from Figure 7 , the uranium removal rate of the NiSrTiO3-3 prepared in Example 3 was 96.5%-99.8% within the pH range of 3-9, which confirmed that the uranium removal nickel strontium titanate electrode prepared by the present application had a wide pH range of use.

[0047] The uranium removal nickel strontium titanate electrode prepared in Example 3 was used as an anode, and a titanium sheet was used as a cathode, and then the electrodes were placed in 200 mL of a mixed solution containing coexisting ions (the mixed solution included: uranium ions, chloride ions, nitrate ions, bicarbonate ions, sodium ions, potassium ions, and magnesium ions, and the concentration of each ion was 10 mg / L, and the pH of the mixed solution was 5). The uranium removal effect was tested under the condition that the current density was 5 mA / cm 2 , and the experimental temperature was 25°C for 6 h, and then the mixed solution was replaced (the ion concentration, pH condition, etc. of the mixed solution were unchanged), and after 7 cycles, the uranium removal efficiency was recorded each time, and the results are shown in Figure 8 . As can be seen from Figure 8It can be seen that the removal efficiency of uranium still remains at 98.1% at the 8th cycle, which proves that the nickel strontium titanate electrode prepared by the preparation method of the application has excellent electrochemical stability and service life.

[0048] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, but not to limit them. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can still be modified or equivalently replaced, and these modifications or equivalent replacements should not make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. A method for preparing a nickel strontium titanate electrode from which uranium is removed, characterized in that, The preparation method comprises the following steps: S1, mixing a titanium source, an alcohol amine carrier, and a basic solution to obtain a precursor solution; S2, adding a nickel source and a strontium source to the precursor solution, ultrasonicating, and hydrothermally reacting to obtain a nickel strontium titanate material; S3, coating the nickel strontium titanate material on a surface of a carbon fiber base material to obtain a uranium-removed nickel strontium titanate electrode.

2. The method of claim 1, wherein the method is characterized by: The titanium source in S1 comprises at least one of tetrabutyl titanate, tetraisopropyl titanate, and n-octyl titanate; the alcohol amine carrier comprises at least one of ethanol amine, monoethanol amine, and propanol amine; the basic solution comprises at least one of a sodium hydroxide solution, a potassium hydroxide solution, and ammonia water; and the concentration of the basic solution is 2-2.5 mol / L.

3. The method of claim 2, wherein the method further comprises the step of: The volume ratio of the titanium source, the alcohol amine carrier, and the basic solution in S1 is 2-4:20-30:40-60. ​ 4. The method of claim 1, wherein the method further comprises the step of: 5 annealing the nickel strontium titanate electrode at a temperature of about 600 °C to about 800 °C for about 1 hour to about 10 hours in air. The mixing temperature in S1 is 60-70 DEG C, and the mixing time is 1-1.5 h.

5. The method of claim 1, wherein the method further comprises the step of: The nickel source in S2 is a nickel-containing salt solution with a concentration of 0.05-0.1 mol / L, and the strontium source is a strontium-containing salt solution with a concentration of 0.3-0.5 mol / L; the volume ratio of the nickel source, the strontium source, and the basic solution is 2-3:5-7:40-60. ​ 6. The method of claim 5, wherein the method further comprises the step of: The nickel-containing salt solution comprises at least one of a nickel chloride solution, a nickel nitrate solution, and a nickel sulfate solution; and the strontium-containing salt solution comprises at least one of a strontium nitrate solution, a strontium chloride solution, and a strontium acetate solution. ​ 7. The method of claim 1, wherein the method further comprises the step of: The hydrothermal reaction temperature in S2 is 170-190 DEG C, and the hydrothermal reaction time is 20-30 h. ​ 8. The method for preparing a strontium nickel titanate electrode for uranium removal according to claim 1, characterized in that, The carbon fiber base material in S3 comprises at least one of a carbon cloth electrode, a carbon felt electrode, and a carbon paper electrode, and the coating thickness of the nickel strontium titanate material is 0.3-0.5 mm.

9. A uranium-removed nickel strontium titanate electrode prepared by the preparation method of the uranium-removed nickel strontium titanate electrode according to any one of claims 1-8.

10. The uranium-removed nickel strontium titanate electrode according to claim 9 is used for removing uranium in wastewater.

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