Magnesium-aluminum hydrotalcite as well as preparation method and application thereof
By combining carbon nanotubes with magnesium-aluminum hydrotalcite and employing hydrothermal synthesis and calcination processes, the challenges of controlling crystal phase and particle size in the traditional synthesis of magnesium-aluminum hydrotalcite were solved, achieving efficient adsorption of uranium and improving the stability and adsorption performance of the material.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-23
- Publication Date
- 2026-03-10
AI Technical Summary
Traditional synthesis of magnesium-aluminum hydrotalcite is difficult to precisely control the crystal phase structure and particle size distribution, resulting in low adsorption efficiency, poor selectivity and stability, low raw material utilization, resource waste, and potential environmental hazards.
By combining carbon nanotubes with magnesium-aluminum hydrotalcite and using hydrothermal synthesis and calcination processes, the interlayer structure of magnesium-aluminum hydrotalcite is optimized by controlling the hydrothermal reaction conditions and calcination temperature, resulting in a composite material with high crystallinity and small particle size.
It significantly improves the adsorption capacity and efficiency of magnesium aluminum hydrotalcite, with an adsorption efficiency of up to 99.44% for uranium and an adsorption capacity of up to 17.34 mg/g. It has good repeatability and stability and is suitable for the removal of radioactive pollutants.
Smart Images
Figure CN121627010A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the field of magnesium-aluminum hydrotalcite preparation, and more particularly, the application relates to a magnesium-aluminum hydrotalcite and a preparation method and application thereof. BACKGROUND
[0002] Uranium (U) is one of the most commonly used fuels in the nuclear industry and is also an important component of radioactive wastewater. Uranium exists in the form of the most stable hexavalent uranyl ion (UO2 2+ ) in aqueous solution, and UO2 2+ can be complexed with bicarbonate ions, citrate and plasma proteins in blood, etc., thus having high solubility and migration in the ecological environment. Once absorbed by the human body, uranium can remain in multiple organs of the human body, thus causing various health problems such as cancer and kidney damage. Once uranium enters water bodies, it will pose a serious threat to the ecological environment and human health. Therefore, in the waste liquid containing uranium elements, safe and effective removal of uranium elements has become an important direction in the field of environmental protection.
[0003] Magnesium-aluminum hydrotalcite (Mg-Al-LDHs) is a layered double hydroxide material, and its structural characteristics lie in that magnesium ions and aluminum ions are alternately arranged in a two-dimensional plane to form positively charged layer plates, and anions and water molecules are embedded between the layers to maintain charge balance. The unique two-dimensional layered structure, stable chemical properties, low cost and non-toxicity of magnesium-aluminum hydrotalcite not only have good ion exchange performance and thermal stability, but also have excellent adsorption capacity and catalytic activity, especially in the removal of heavy metal ions (such as Pb2 + , Cr3 + , UO2 2+ ) and other pollutants, and exhibit wide application potential. With further demand in the field of environmental pollution, magnesium-aluminum hydrotalcite has very important practical significance for removing radioactive pollutants from water bodies.
[0004] Traditional synthesized Mg-Al-LDHs are usually difficult to accurately control the crystal phase structure and particle size distribution of magnesium-aluminum hydrotalcite, thus affecting its performance in practical applications, especially in terms of adsorption efficiency, selectivity and stability, and the purification efficiency for complex wastewater is low. In addition, the utilization rate of raw materials is low in the traditional synthesis method, which not only causes resource waste, but also may produce harmful waste to the environment.
[0005] Therefore, it is necessary to provide a new type of magnesium-aluminum hydrotalcite and a preparation method and application thereof. SUMMARY
[0006] The purpose of the present application is to overcome at least one defect of the prior art, and to provide a new type of magnesium-aluminum hydrotalcite and a preparation method and application thereof.
[0007] To achieve the above-mentioned object of the present application, the present application provides a preparation method of magnesium-aluminum hydrotalcite, comprising:
[0008] S1, acid pretreatment of carbon nanotubes, comprising: S11, preparing a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid; S12, adding carbon nanotube powder into the mixed acid solution, and sequentially performing magnetic stirring and ultrasonic dispersion to obtain a mixed solution; S13, diluting and stirring the mixed solution by pouring it into deionized water, and performing suction filtration and repeated washing on the diluted mixed solution, separating and collecting carbon nanotube precipitate, and drying the collected carbon nanotube to obtain a carbon nanotube pretreatment product;
[0009] S2, preparation of magnesium-aluminum hydrotalcite / carbon nanotube composite material, comprising: S21, pouring CO(NH2)2, Mg(NO3)2.6H2O and Al(NO3)3.9H2O into a beaker according to a certain proportion, adding deionized water, and stirring and dissolving to obtain a mixed solution; S22, adding the carbon nanotube pretreatment product obtained in step S13 into the mixed solution of step S21, stirring and applying ultrasonic waves to make the carbon nanotubes fully dispersed to obtain a dispersion liquid; S23, transferring the dispersion liquid obtained in step S22 into a hydrothermal synthesis reaction kettle, placing it into a constant-temperature drying box, and performing hydrothermal synthesis reaction at a constant temperature to obtain a precipitate; S24, after the completion of the hydrothermal synthesis reaction, taking out the hydrothermal reaction kettle and cooling it to room temperature, centrifuging and filtering the generated precipitate, and repeatedly washing it with deionized water, and finally replacing the deionized water with ethanol for centrifugation and filtration, and drying to obtain a hydrotalcite-like precursor;
[0010] S3, preparation of magnesium-aluminum hydrotalcite: placing the dried hydrotalcite-like precursor into an air atmosphere, and performing calcination treatment using a muffle furnace to obtain magnesium-aluminum hydrotalcite.
[0011] According to one embodiment of the preparation method of magnesium-aluminum hydrotalcite of the present application, in step S11, the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is 3:1.
[0012] According to one embodiment of the preparation method of magnesium-aluminum hydrotalcite of the present application, in step S12, magnetic stirring is performed at room temperature using a magnetic stirrer, and the stirring time is 1-10 h.
[0013] According to one embodiment of the preparation method of magnesium-aluminum hydrotalcite of the present application, in step S12, ultrasonic dispersion is performed in an ultrasonic cleaner, the water temperature of the ultrasonic cleaner is 70-80℃, and the ultrasonic dispersion time is 5-10 h.
[0014] According to one embodiment of the preparation method of magnesium-aluminum hydrotalcite of the present application, in step S13, when performing suction filtration, pH test paper is used to detect the pH value of the filtrate until the pH value is 7.
[0015] According to one embodiment of the preparation method of the magnesium-aluminum hydrotalcite, in the step S13, the drying temperature of the carbon nanotube is 60-100 DEG C, and the drying time is 6-24h.
[0016] According to one embodiment of the preparation method of the magnesium-aluminum hydrotalcite, in the step S21, the molar ratio of CO(NH2)2, Mg(NO3)2.6H2O and Al(NO3)3.9H2O is n[CO(NH2)2]:n(Mg 2+ +Al 3+ )]=10:1, n(Mg 2+ ):n(Al 3 + )=(2.5-3):1.
[0017] According to one embodiment of the preparation method of the magnesium-aluminum hydrotalcite, in the step S23, the hydrothermal constant temperature of the hydrothermal synthesis reactor is 140-200 DEG C, and the hydrothermal constant time is 10-24h.
[0018] According to one embodiment of the preparation method of the magnesium-aluminum hydrotalcite, in the step S24, the purity of the deionized water is EC<1us / cm.
[0019] According to one embodiment of the preparation method of the magnesium-aluminum hydrotalcite, in the step S3, the calcination temperature of the hydrotalcite-like precursor calcination treatment is 500-800 DEG C, and the calcination time is 2-10h.
[0020] In order to achieve the above-mentioned purposes, the application further provides a magnesium-aluminum hydrotalcite prepared by the preparation method of the magnesium-aluminum hydrotalcite.
[0021] In order to achieve the above-mentioned purposes, the application further provides the application of the magnesium-aluminum hydrotalcite in the adsorption of uranium elements.
[0022] Compared with the prior art, the preparation method of the magnesium-aluminum hydrotalcite has at least the following advantages:
[0023] The preparation method of the magnesium-aluminum hydrotalcite composites the carbon nanotube with the magnesium-aluminum hydrotalcite, obtains the carbon nanotube / magnesium-aluminum hydrotalcite composite material with higher crystallinity and smaller particle size, optimizes and adjusts by removing the carbon nanotube through calcination, temporarily collapses the interlayer structure of the magnesium-aluminum hydrotalcite material, greatly increases the specific surface area, effectively controls the particle size of the hydrothermal synthesis, significantly enhances the adsorption capacity and adsorption efficiency of the magnesium-aluminum hydrotalcite material, and obtains the magnesium-aluminum hydrotalcite with higher crystallinity and better adsorption performance.
[0024] This invention innovatively employs an integrated process combining hydrothermal homogeneous precipitation and calcination to prepare magnesium-aluminum hydrotalcite, overcoming the limitations of traditional magnesium-aluminum hydrotalcite preparation techniques. By precisely controlling the crystallization kinetics through a hydrothermal method, it effectively overcomes technical bottlenecks such as insufficient crystallinity and excessively wide particle size distribution caused by conventional methods, significantly enhancing the stability and adsorption performance of the magnesium-aluminum hydrotalcite material. The magnesium-aluminum hydrotalcite provided by this invention exhibits an adsorption efficiency of up to 99.44% for radioactive uranium and an adsorption capacity as high as 17.34 mg / g, making it a highly efficient uranium adsorbent material that can be used as an adsorbent for radioactive uranium, contributing to environmental protection and improving pollution treatment efficiency. Attached Figure Description
[0025] The magnesium-aluminum hydrotalcite of the present invention, its preparation method, and its applications will be described in detail below with reference to the accompanying drawings and specific embodiments, wherein:
[0026] Figure 1 This is a schematic flowchart of the preparation method of magnesium-aluminum hydrotalcite of the present invention.
[0027] Figure 2A and Figure 2B These are surface morphology images of the magnesium-aluminum hydrotalcite material prepared in Example 1 of the present invention, taken at different shooting positions. Figure 2A Magnification is 2200 (scale bar: 10μm). Figure 2B The magnification is 1600 (scale bar: 10μm).
[0028] Figure 3 This experiment demonstrates the selective adsorption of radioactive uranium onto the magnesium-aluminum hydrotalcite material prepared by the method described in Example 1 of this invention.
[0029] Figure 4 This is a static adsorption experiment of radioactive uranium on magnesium aluminum hydrotalcite prepared by the preparation method of magnesium aluminum hydrotalcite in Example 1 of the present invention. Detailed Implementation
[0030] To make the objectives, technical solutions, and effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described in this specification are merely for explaining the invention and are not intended to limit the invention.
[0031] Example 1: Preparation of magnesium aluminum hydrotalcite
[0032] Please refer to Figure 1 As shown, the preparation method of magnesium aluminum hydrotalcite of the present invention includes the following steps:
[0033] S1. Pretreatment of carbon nanotubes: S11. Prepare a mixed acid solution with a volume ratio of concentrated sulfuric acid to concentrated nitric acid of 3:1. Perform this in a fume hood. Use two 50ml beakers to take 30ml of concentrated sulfuric acid and 10ml of concentrated nitric acid respectively. Slowly pour the concentrated sulfuric acid into the concentrated nitric acid along the beaker wall, stirring constantly with a glass rod to dissipate heat. S12. Ultrasonic dispersion and heat treatment of carbon nanotubes: Place 3g of carbon nanotube powder into a 100ml beaker, add the prepared mixed acid solution, and stir evenly with a glass rod. Seal the mouth of the beaker with plastic wrap and stir with a magnetic stirrer for 1 hour at room temperature. After stirring, transfer to an ultrasonic cleaner, adjust the water temperature in the ultrasonic cleaner to 80℃, and ultrasonically disperse for 5 hours. S13. Separation of carbon nanotubes: After the above operations are completed, remove the small beaker and slowly pour the mixed solution containing carbon nanotubes into water along the glass rod for dilution. Stir continuously with the glass rod to dissipate heat. Filter the diluted solution and discard the filtrate. Add deionized water to the obtained product and filter repeatedly. Use a pH meter to detect the pH value of the filtrate until pH=7. Finally, use ethanol instead of deionized water for filtration to separate the carbon nanotubes and collect the carbon nanotube precipitate. S14. Drying carbon nanotubes: Place the collected carbon nanotubes in a drying oven and dry at 60℃ for 12 hours to obtain the pretreated carbon nanotube product.
[0034] S2. Preparation of magnesium-aluminum hydrotalcite material: S21. Mix urea, magnesium nitrate hexahydrate, and aluminum nitrate nonahydrate in a molar ratio of n[CO(NH2)2]:n(Mg) 2+ +Al 3+ ) = 10:1, n(Mg 2+ ): n(Al 3+ The experiment was conducted with a ratio of 2.5:1. 42g of CO(NH2)2, 12.8g of Mg(NO3)2·6H2O, and 7.5g of Al(NO3)3·9H2O were weighed and dissolved in 200mL of deionized water. The solution was stirred with a magnetic stirrer until dissolved. S22. 0.3g of pretreated carbon nanotubes were added to the solution, stirred, and then sonicated for 30min to ensure complete dispersion. S23. The solution was transferred to a 300ml hydrothermal synthesis reactor lined with polytetrafluoroethylene. The reactor was placed in an oven and crystallized at 140℃ for 24h. The reactor was then removed and cooled to room temperature. The resulting precipitate was centrifuged and filtered, then repeatedly washed with deionized water. Finally, ethanol was used instead of deionized water for centrifugation. The precipitate was dried at 60℃ for 10h to obtain a hydrotalcite-like precursor.
[0035] S3. Place the initial hydrotalcite precursor sample into a crucible and calcine it at 500°C for 3 hours in a box-type resistance furnace to obtain magnesium aluminum hydrotalcite material 1.
[0036] Figure 2A and Figure 2BThe images shown are surface morphology images of different locations of the magnesium-aluminum hydrotalcite material obtained in Example 1 of this invention. The images were taken using a scanning electron microscope (JSM-IT500LV) manufactured by JEOL Ltd. of Japan. Figure 2A Magnification is 2200 (scale bar: 10μm). Figure 2B The magnification is 1600 (scale bar: 10μm). From Figure 2A and 2B As can be seen, the layered structure formed by the stacking of thin sheets is clearly visible, indicating that magnesium aluminum hydrotalcite was successfully synthesized during the preparation process.
[0037] Example 2: Preparation of magnesium aluminum hydrotalcite material
[0038] Except for the ultrasonic water temperature of 70℃, 75℃, and 80℃, the other conditions are the same as in Example 1, and are referred to as magnesium aluminum hydrotalcite materials 2, 3, and 4.
[0039] Example 3: Preparation of magnesium aluminum hydrotalcite material
[0040] Except for the ultrasonic dispersion time of 5h, 8h, and 10h, the other conditions are the same as in Example 1, and are referred to as magnesium aluminum hydrotalcite materials 5, 6, and 7.
[0041] Example 4: Preparation of magnesium aluminum hydrotalcite material
[0042] Except for n(Mg) 2+ ): n(Al 3+ Except for changing the ratio to 2.5:1, 2.8:1, or 3:1, everything else is the same as in Example 1, and they are referred to as magnesium aluminum hydrotalcite materials 8, 9, and 10.
[0043] Example 5: Preparation of magnesium aluminum hydrotalcite material
[0044] Except for the hydrothermal temperature being changed to 160℃, 180℃, and 200℃, the other conditions are the same as in Example 1, and are referred to as magnesium aluminum hydrotalcite materials 11, 12, and 13.
[0045] Example 6: Preparation of Magnesium Aluminum Hydrotalcite Material
[0046] Except for the hydrothermal time being changed to 12h, 18h, and 24h, the other methods are the same as in Example 1, and are referred to as magnesium aluminum hydrotalcite materials 14, 15, and 16.
[0047] Example 7: Preparation of Magnesium Aluminum Hydrotalcite Material
[0048] Except for the calcination temperature being changed to 500℃, 600℃, and 800℃, the rest is the same as in Example 1, and they are referred to as magnesium aluminum hydrotalcite materials 17, 18, and 19.
[0049] Example 8: Preparation of magnesium aluminum hydrotalcite material
[0050] Except for the calcination time being changed to 2h, 5h, and 10h, the rest is the same as in Example 1, and are referred to as magnesium aluminum hydrotalcite materials 20, 21, and 22.
[0051] In the above embodiments, all pharmaceutical products were purchased from Aladdin. The multi-walled carbon nanotubes had an outer diameter of 8-50 nm, a length of <50 μm, and a specific surface area >140 m². 2 / g, and all percentages in the examples are mass percentages.
[0052] Specific steps for the uranium adsorption selectivity experiment:
[0053] Experimental instrument: ICP-AES (Inductively Coupled Plasma Optical Emission Spectrometer, HORIBA Corporation, Japan, model Ultima Expert)
[0054] Experimental steps:
[0055] S1. Weigh 16 mg UO2(NO3)2·6H2O, 16 mg potassium chloride (KCl), 16 mg sodium chloride (NaCl), 16 mg calcium chloride (CaCl2), and 16 mg magnesium chloride (MgCl2), dissolve them in 1 L of deionized water, and prepare U... 4+ :K + Na + Ca 2+ Mg 2+ A mixed ionic solution with a mass concentration ratio of 1:1:1:1:1 (1 ppm = 1 mg / L) was prepared. The above mixed solution was divided into three equal portions, and a small amount of dilute hydrochloric acid was added to adjust the pH value of the solution to obtain solutions with pH=4, pH=5, and pH=6, respectively.
[0056] S2. Take a small amount of the initial mixed solution with different pH values and use an ICP-AES instrument to determine the initial concentration of U(IV) in the stock solution. Since adjusting the pH of the solution may cause changes in concentration, the actual initial concentration of U(IV) should be based on the result measured by the ICP-AES instrument.
[0057] S3. Take 5 mL of mixed ionic solutions under different pH conditions and place them in sealable transparent glass bottles. Then add 0.02 g of the magnesium aluminum hydrotalcite material prepared in Example 1 to each bottle. Place the bottles in a 25°C constant temperature water bath shaker and shake at 160 rpm for 10 minutes to allow the material to react with various coexisting ions (K+, K+, K+). + Na + Ca 2+ Mg 2+ Under the interference of ), it selectively adsorbs U(IV).
[0058] S4. After shaking, the remaining concentration of U(IV) in the supernatant was determined using an ICP-AES instrument, and the uranium adsorption rate was calculated using the formula: U adsorption rate = (initial U concentration - remaining U concentration) / initial U concentration. The experimental conditions and results are as follows: Figure 3 As shown.
[0059] from Figure 3 It can be seen that the magnesium-aluminum hydrotalcite prepared by the method of the present invention can be used as an adsorbent for uranium in the water pollution control industry. It has an adsorption efficiency of up to 99.44% for radioactive uranium, making it a highly efficient uranium adsorbent material. Its application as an adsorbent for radioactive uranium is beneficial to environmental protection and improves pollution treatment efficiency.
[0060] Figure 4 The static adsorption experiment of radioactive uranium on the magnesium-aluminum hydrotalcite material prepared in Example 1 was conducted under the test conditions of pH = 7, m / V = 0.003, T = 25℃, and [U] = 20ppm. Figure 4 As can be seen, the magnesium-aluminum hydrotalcite prepared in this invention has an adsorption capacity of up to 17.34 mg / g for uranium.
[0061] Based on the above detailed description of the embodiments of the present invention, it can be seen that, compared with the prior art, the preparation method of magnesium aluminum hydrotalcite of the present invention has at least the following advantages:
[0062] This invention discloses a method for preparing magnesium-aluminum hydrotalcite (MgA) by combining carbon nanotubes with MgA to obtain a carbon nanotube / MgA A toluene composite material with higher crystallinity and smaller particle size. Further optimization is achieved by removing carbon nanotubes through calcination, which temporarily collapses the interlayer structure of the MgA A toluene material, significantly increasing its specific surface area. This effectively controls the particle size generated by hydrothermal synthesis, significantly enhancing the adsorption capacity and efficiency of the MgA A toluene material, and resulting in MgA A toluene with higher crystallinity and better adsorption performance. After adsorbing water molecules and anions, the MgA A toluene material gradually restores its original interlayer structure, exhibiting good repeatability and stability.
[0063] This invention innovatively employs an integrated process combining hydrothermal homogeneous precipitation and calcination to prepare magnesium-aluminum hydrotalcite, significantly overcoming the limitations of traditional magnesium-aluminum hydrotalcite preparation techniques. By precisely controlling the crystallization kinetics through a hydrothermal method, it effectively overcomes technical bottlenecks such as insufficient crystallinity and excessively wide particle size distribution caused by conventional methods, significantly enhancing the stability and adsorption performance of the magnesium-aluminum hydrotalcite material. The magnesium-aluminum hydrotalcite provided by this invention exhibits an adsorption efficiency of up to 99.44% for radioactive uranium and an adsorption capacity as high as 17.34 mg / g, making it a highly efficient uranium adsorbent material that can be used as an adsorbent for radioactive uranium, contributing to environmental protection and improving pollution treatment efficiency.
[0064] Based on the above principles, the present invention can also make appropriate changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the present invention.
Claims
1. A process for the preparation of a magnesium aluminium hydrotalcite, characterised in that, The preparation method of the magnesium-aluminum hydrotalcite comprises the following steps: S1, acid pretreatment of carbon nanotubes, comprising: S11, preparing a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid; S12, adding carbon nanotube powder into the mixed acid solution, and sequentially performing magnetic stirring and ultrasonic dispersion to obtain a mixed solution; S13, diluting and stirring the mixed solution by pouring it into deionized water, and then performing suction filtration and repeated washing on the diluted mixed solution, and then separating and collecting carbon nanotube precipitate, and then drying the collected carbon nanotube to obtain a carbon nanotube pretreatment product; S2, preparation of magnesium-aluminum hydrotalcite / carbon nanotube composite material, comprising: S21, pouring CO(NH2)2, Mg(NO3)2·6H2O and Al(NO3)3·9H2O into a beaker according to a certain proportion, adding deionized water, and stirring and dissolving to obtain a mixed solution; S22, adding the carbon nanotube pretreatment product obtained in step S13 into the mixed solution in step S21, stirring and applying ultrasonic waves to completely disperse the carbon nanotube, and obtaining a dispersion liquid; S23, transferring the dispersion liquid obtained in step S22 into a hydrothermal synthesis reaction kettle, placing it into a constant-temperature drying box, and performing hydrothermal synthesis reaction at a constant temperature to obtain a precipitate; S24, after the completion of the hydrothermal synthesis reaction, taking out the hydrothermal reaction kettle and cooling it to room temperature, centrifuging and filtering the generated precipitate, repeatedly washing it with deionized water, and finally performing centrifugation and filtration with ethanol instead of deionized water, and then drying to obtain a hydrotalcite-like precursor; S3, preparation of magnesium-aluminum hydrotalcite: placing the dried hydrotalcite-like precursor into an air atmosphere, and performing calcination treatment by using a muffle furnace to obtain the magnesium-aluminum hydrotalcite.
2. The method for producing magnesium-aluminum hydrotalcite according to claim 1, characterized by, In the step S11, the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is 3:
1.
3. The method of preparing magnesium aluminometallic ferrite according to claim 1, characterized by, In the step S12, the magnetic stirrer is used for stirring at room temperature, and the stirring time is 1-10 h.
4. The method of preparing magnesium aluminum hydrotalcite according to claim 1, characterized by, In the step S12, the ultrasonic dispersion is performed in an ultrasonic cleaner, the water temperature of the ultrasonic cleaner is 70-80℃, and the ultrasonic dispersion time is 5-10 h.
5. The method of preparing magnesium aluminum hydrotalcite according to claim 1, characterized by, In the step S13, when performing suction filtration, the pH value of the filtrate is detected by using pH test paper until the pH value is 7.
6. The method of preparing magnesium aluminum hydrotalcite according to claim 1, characterized by, In the step S13, the drying temperature of the carbon nanotube is 60-100℃, and the drying time is 6-24 h.
7. The method of preparation of magnesium aluminometallic ferrite according to claim 1, characterized in that, The molar ratio of CO(NH2)2, Mg(NO3)2·6H2O and Al(NO3)3·9H2O in the step S21 is n[CO(NH2)2]:n(Mg 2+ +Al 3+ )=10:1, n(Mg 2+ ):n(Al 3+ )=(2.5-3):
1.
8. The method of preparation of magnesium aluminometallic ferrite according to claim 1, characterized in that, In the step S23, the hydrothermal constant-temperature temperature of the hydrothermal synthesis reaction kettle is 140-200℃, and the hydrothermal constant-temperature time is 10-24 h.
9. The method for preparing magnesium-aluminum hydrotalcite according to claim 1, characterized in that, In the step S24, the purity of the deionized water is EC<1 us / cm.
10. The method of producing magnesium aluminum hydrotalcite according to claim 1, characterized by, In the step S3, the calcination temperature of the calcination treatment of the hydrotalcite-like precursor is 500-800℃, and the calcination time is 2-10 h.
11. A magnesium aluminium hydrotalcite characterised in that, The magnesium-aluminum hydrotalcite is prepared according to the preparation method of the magnesium-aluminum hydrotalcite in any one of claims 1-10.
12. The magnesium-aluminum hydrotalcite according to claim 11, applied in uranium element adsorption.