System and method for automatically synthesizing binary and ternary layered double hydroxides

Abstract

The invention relates to the field of metal hydroxide material synthesis, in particular to a system for automatically synthesizing binary and ternary layered double hydroxides, which comprises a control module, a signal receiving module, a solution mixing module, an automatic pump module, an automatic valve module, a reaction module and a power supply, the control module is configured to send a synthesis instruction to the signal receiving module; the signal receiving module is configured to receive and process the instruction and send control signals to the automatic pump module, the automatic valve module, the solution mixing module and the reaction module; the automatic valve module is provided with a middle interface and a plurality of peripheral interfaces, the middle interface is connected with the automatic pump module, and the peripheral interfaces can be connected to a solution source, a solution mixing module or a reaction module; the automatic pump module is configured to draw or discharge liquid under the control signal. According to the invention, the automatic preparation of the hydrotalcite material can be realized, the manpower is saved, the synthesis stability and repeatability are improved, the risk of toxic substances is reduced, and the development of the hydrotalcite research field is promoted.

Description

Technical Field

[0001] This invention relates to the field of synthesis of two-dimensional layered metal hydroxide materials (LDHs), specifically a system and method for the automated synthesis of binary and ternary layered double hydroxides (LDHs). Background Technology

[0002] Hydrotalcite, whose main body is generally composed of hydroxides of two or more metals, is also known as layered double hydroxides (LDHs). The structural formula of hydrotalcite is: [M... 2+ 1-x M 3+ x [(OH)2](A n- ) x / n ·mH2O, some of the divalent metal cations (M) on these plates 2+ ) by trivalent metal cations (M 3+ The replacement of M makes the layer positively charged, where M 2+ M 3+ It can be one or more of the following elements: Mg, Zn, Ca, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, In; x represents M. 3+ / (M 2+ +M 3+ The molar ratio of ); the positive charge carried by the plates is generated by interlayer anions (A n- To balance, A n- It can be CO3 2- NO 3- Cl - SO4 2- And polyoxometalates, etc.; m is the molar amount of water molecules in the interlayer. Due to the structural characteristics of hydrotalcite, it has the characteristics of adjustable layer size and thickness, controllable constituent elements, and variable interlayer anions, and is widely used in many fields such as thermocatalysis, photocatalysis, electrocatalysis, biosensing, medicine, and airtight materials.

[0003] As is well known, the structure of a material determines its properties. To meet diverse application needs, researchers have developed various methods for synthesizing hydrotalcite to prepare hydrotalcites with specific properties. The emergence of new synthesis methods, and the diverse types of hydrotalcite obtained using existing methods, have greatly enriched this material system, demonstrating broad application prospects. The core of hydrotalcite synthesis is the mixing process of alkaline and salt solutions, requiring control of stirring time at different crystallization temperatures. Traditional methods (such as single-drop, double-drop, and hydrothermal methods) suffer from low yields, poor reproducibility, and operational hazards; while colloid milling can achieve large-scale rapid synthesis, it is still limited by insufficient reproducibility and high labor costs.

[0004] However, mastering the numerous methods and details of hydrotalcite synthesis often requires significant time and experience. Automated synthesis technology, by integrating different methods, can efficiently prepare target hydrotalcites, significantly saving labor costs and allowing researchers to focus their efforts on material discovery and mechanism research. Simultaneously, automated devices enable non-specialist personnel to synthesize materials on demand. For toxic and hazardous substances, this technology can mitigate operational risks and improve safety. Furthermore, coded steps ensure the repeatability and stability of experiments, promoting communication and development in hydrotalcite research. Summary of the Invention

[0005] This invention aims to provide a system and method for the automated synthesis of binary and ternary layered double hydroxides (LDHs), which can save manpower, improve synthesis stability and reproducibility, reduce the risk of toxic substances, and promote the development of the field of hydrotalcite research by automating the preparation of hydrotalcite materials.

[0006] To achieve the above objectives, the technical solution specifically adopted by the present invention is as follows: An automated system for synthesizing binary and ternary layered double hydroxides includes a control module, a signal receiving module, a solution mixing module, an automatic pump module, an automatic valve module, a reaction module, and a power supply; wherein, The control module is configured to send a synthesis command to the signal receiving module; The signal receiving module is configured to receive and process the instructions, and send control signals to the automatic pump module, automatic valve module, solution mixing module and reaction module; The automatic valve module has an intermediate interface and multiple peripheral interfaces. The intermediate interface is connected to the automatic pump module, and the peripheral interfaces can be connected to a solution source, a solution mixing module, or a reaction module. The automatic pump module is configured to draw in or discharge liquid upon receiving a control signal.

[0007] Furthermore, the intermediate interface of the automatic valve module can be connected to any external interface via control.

[0008] Further, the material transfer includes: The automatic valve module opens the external interface connecting to the target solution, allowing the automatic pump module to draw in the solution; The automatic valve module opens the external interface connecting the solution mixing module or reaction module, causing the automatic pump module to discharge liquid into the solution mixing module or reaction module.

[0009] Furthermore, the system is configured to control material transfer via signal transmission. The signal transmission path includes: control module → signal receiving module → automatic pump module / automatic valve module / solution mixing module / reaction module. Specifically, the automation device includes signal transmission and material transfer. Information transmission involves the control module sending instructions to the signal receiving module, which then sends signals to the corresponding automatic pump module / automatic valve module, solution mixing module, and reaction module. Upon receiving the signal, the device performs the corresponding operation, thereby controlling the entire device. Material transfer is mainly achieved through the automatic valve module and the automatic pump module. The automatic valve module has an intermediate interface and an external interface. The intermediate interface can be connected to any external interface via control. Generally, the intermediate interface of the automatic valve module is connected to the automatic pump module, while the external interface is connected to different solutions, mixers, or reaction modules. When a target solution needs to be extracted, the automatic valve module is controlled to open the external interface connected to the target solution. At this time, the automatic pump module connected to the intermediate interface and the external interface connected to the target solution are connected, allowing the automatic pump module to draw the required amount of solution, thus completing the extraction task. After the extraction task is completed, the automatic valve module opens the interface connecting to the mixer or reaction module, and the automatic pump module discharges the extracted liquid, so that the required liquid can be transferred to the mixer or reaction module for mixing or reaction.

[0010] Furthermore, the specific chemical formula of the synthesized hydrotalcite material is [M 2+ 1-x M 3+ x (OH)2] x+ ·(A n- ) (x / n) ·mH2O, where M 2+ It is Mg 2+ Co 2+ Ni 2+ or Zn 2+ At least one of them; M 3+ It is Fe 3+ V 3+ Cr 3+ Mn 3+ At least one of them, 0.2≤x≤0.33, A n- It is NO3 - Cl - or CO3 2- n is the valence of the anion; m is the amount of water of crystallization, ranging from 0.5 to 9. By precisely controlling the synthesis method, different binary and ternary hydrotalcites can be synthesized.

[0011] This invention also provides an automated method for synthesizing binary and ternary layered double hydroxides, which, based on the above-described system, prepares binary and / or ternary hydrotalcites, comprising the following steps: (a) Prepare a mixed solution of divalent and trivalent metal salts with a total concentration of 0.01-1.00 mol / L and place it in a salt solution bottle; (b) Prepare an alkaline solution with a concentration of 0.01-0.2 g / ml and place it in an alkaline solution bottle; (c) Prepare an additive solution with a concentration of 0.01-1 mol / L and place it in an additive solution bottle; (d) The mixed solution is drawn into the mixer through the automatic pump module and the automatic valve module to form solution A with a molar ratio of divalent to trivalent metal ions of 2.0-4.0; (e) 1-400 ml of alkaline solution is drawn through the automatic pump module and the automatic valve module to form solution B; (f) Extract 1-400ml of additive solution through the automatic pump module and automatic valve module to form solution C; (g) Perform any of the following operations: (i) Single drop method: Add solution A dropwise to the mixture of solution B and solution C at a rate of 0.01-10 ml / min, while stirring at a rate of 0-1000 rpm; (ii) Double drop method: The mixture of solution A, solution B, and solution C is simultaneously dropped into the reaction module at a rate of 0.01-10 ml / min, and the stirring rate is 0-1000 rpm; (h) Crystallize the reaction solution at 25-100℃ for 0-24 hours; (i) Filter or centrifuge washing to obtain hydrotalcite material.

[0012] Furthermore, the divalent metal salt is selected from salts of Mg, Zn, Ca, Mn, Fe, Co, Ni, and Cu; The trivalent metal salt is selected from salts of Al, Cr, Fe, In, and Rh; The alkaline solution is NaOH, sodium carbonate, ammonia, urea, or hexamethylenetetramine solution; The additive is formamide, ammonium fluoride, boric acid, sodium dodecyl sulfate, or tris(hydroxymethyl)aminomethane.

[0013] Furthermore, in step (d), Ti is further incorporated. 4+ ,Rh 3+ Or Ru 3+ Metal salt solution.

[0014] Furthermore, the automatic valve module is connected to the automatic pump module via an intermediate interface, and to a solution source, mixer, or reaction module via an external interface; solution transfer is controlled by switching interface paths. This invention presents a modularly designed device for the automated synthesis of binary and ternary hydrotalcites, based on the conditions for hydrotalcite synthesis and the controllable and adjustable factors of hydrotalcite. This device offers the following significant advantages: 1) Digital precision control: Under digital control, the reliability and consistency of experimental results are ensured; 2) Remote intelligent operation: Supports remote control via the Internet, reducing manpower input and enabling researchers to focus on the exploration and understanding of new materials (such as LDH nanomaterials); 3) Non-expert friendly: Untrained non-chemists can easily operate and synthesize the required hydrotalcite on demand; 4) Enhanced safety: Automated processing of toxic and hazardous substances, mitigating operational risks; 5) Scalability potential: Currently capable of laboratory-scale synthesis, but can be upgraded to large-scale production by increasing the size of the syringe pump. Attached Figure Description

[0015] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a block diagram of a system for automatically synthesizing binary and ternary layered double hydroxides according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the connection method of the automatic hydrotalcite synthesis device in an embodiment of the present invention.

[0016] Figure 3 This is the piping connection diagram for automatic valve No. 2.

[0017] Figure 4 This is the piping connection diagram for automatic valve No. 3.

[0018] Figure 5 The image shows the XRD results of MgAl-LDH synthesized in Example 2 of this invention.

[0019] Figure 6 The image shows the XRD results of the MgFe-LDH synthesized in Example 3 of this invention.

[0020] Figure 7 The image shows the XRD results of MgFeAl-LDH synthesized in Example 4 of this invention.

[0021] Figure 8 This is a schematic diagram showing the adsorption performance of Ni on the three hydrotalcites synthesized in this embodiment of the invention: MgFe-LDH, MgAl-LDH, and MgFeAl-LDH. Detailed Implementation

[0022] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. Example 1

[0023] Design principle and connection method of automatic hydrotalcite synthesis device like Figure 1 As shown, this embodiment of the invention provides a system for the automated synthesis of binary and ternary layered double hydroxides, including a control module, a signal receiving module, a solution mixing module, an automatic pump module, an automatic valve module, a reaction module, and a power supply. The control module is configured to send synthesis instructions to the signal receiving module. The signal receiving module is configured to receive and process the instructions, and send control signals to the automatic pump module, the automatic valve module, the solution mixing module, and the reaction module. The automatic valve module has an intermediate interface and multiple peripheral interfaces. The intermediate interface is connected to the automatic pump module, and the peripheral interfaces can be connected to a solution source, the solution mixing module, or the reaction module. The automatic pump module is configured to draw in or discharge liquid upon receiving a control signal.

[0024] Based on the specific synthesis method of hydrotalcite, this example is equipped with two vertical injection pumps (automatic pump modules), labeled Pump 0 and Pump 1. It also includes two switching valves (automatic valve modules), labeled Valve 2 and Valve 3. A signal receiving module is provided, which can connect via wired or WiFi connection to receive commands from a computer. A power supply is provided to power the automatic pump modules, automatic valve modules, and signal receiving modules. The connections of the automatic pump modules, automatic valve modules, mixer, and synthesizer are as follows: Figure 2 As shown. The maximum capacity of the automatic pump module is 20ml. The automatic valve module has 11 connection ports, and the middle port can be connected to any of the other 10 ports. Pump 1 and valve 2 are connected via their middle interfaces, and pump 0 and valve 3 are connected via their middle interfaces. Figure 3 This is a piping connection diagram for the No. 2 automatic valve module and the solution bottle. In the No. 2 automatic valve module, port 1 is connected to air, port 2 is connected to the synthesizer, port 3 is connected to Co salt, port 4 is connected to Ni salt, port 5 is connected to V or Cr salt, port 6 is connected to the mixer, port 7 is connected to Mn salt, port 8 is connected to Fe salt, port 9 is connected to ultrapure water, and port 10 is connected to waste liquid. Figure 4 This is a piping connection diagram for the No. 3 automatic valve module and the solution bottle. The No. 3 automatic valve module is connected to air, synthesizer, Zn salt, Mg salt, Al salt, mixer, additive, alkali solution, ultrapure water, and waste liquid from port 1 to port 10, respectively. Example 2

[0025] Automatic synthesis of Mg3Al-LDH - single drop The connection is made using the description in Example 1. The synthesis of the automatic hydrotalcite is controlled by a computer. The automatic control commands are intelligently sent by the computer, and the commands are written without human intervention. The specific command content is as follows.

[0026] S1. Return all pumps and valves to the zero position.

[0027] S2. Turn valve 3 to port 4 and use pump 0 to draw 15 ml of 0.2 mol / L Mg(NO3)2·6H2O solution.

[0028] S3. Turn valve #3 to port #6 and use pump #0 to push 15ml of liquid into the mixer.

[0029] S4. Turn valve 3 to port 9 and use pump 0 to draw 20ml of pure water. Then turn valve 3 to port 10 and use pump 0 to discharge 20ml of liquid. Repeat this step 3 times to clean pump 0.

[0030] S5. Turn valve 3 to port 5 and use pump 0 to draw 5 ml of 0.2 mol / L Al(NO3)3·9H2O solution.

[0031] S6. Turn valve #3 to port #6 and use pump #0 to push 5ml of liquid into the mixer.

[0032] S7. Use the command in step S4 to clean pump 0.

[0033] S8. Turn valve 3 to port 8 and use pump 0 to draw 20 ml of a solution containing 1 g / 100 ml NaOH and 0.2 mol / L Na2CO3.

[0034] S9. Turn valve #3 to port #2 and use pump #0 to push 20ml of liquid into the synthesizer.

[0035] S10. Use the command in step S4 to clean pump 0.

[0036] S11. Turn valve 3 to port 6 and use pump 0 to draw 20ml of salt solution.

[0037] S12. Turn valve 3 to port 2, use pump 0 to drop the solution into the synthesizer at a rate of 1 ml / min, turn on the stirrer, set the stirring speed to 500 rpm, the crystallization temperature to room temperature, and the duration to 20 min.

[0038] S13. Turn valve 2 to port 9 and use pump 1 to draw 20ml of pure water. Then turn valve 2 to port 10 and use pump 0 to discharge 20ml of liquid. Repeat this step 3 times to clean pump 1.

[0039] S14. Use the commands in step S4 to clean pump 0.

[0040] S15. Return all pumps and valves to the zero position.

[0041] S16. Centrifuge and wash the product, then dry it at 60°C to obtain the sample. The XRD pattern of the sample is shown below. Figure 5 As shown.

[0042] like Figure 5 As shown, XRD results indicate that MgAl-LDH was successfully synthesized. Example 3

[0043] Automatic synthesis of Mg3Fe-LDH - double drop The connection is made using the description in Example 1. The synthesis of the automatic hydrotalcite is controlled by a computer. The automatic control commands are intelligently sent by the computer, and the commands are written without human intervention. The specific command content is as follows.

[0044] S1. Return all pumps and valves to the zero position.

[0045] S2. Turn valve 3 to port 4 and use pump 0 to draw 3.75 ml of 0.2 mol / L Mg(NO3)2·6H2O solution.

[0046] S3. Turn valve #3 to port #6 and use pump #0 to push 3.75ml of liquid into the mixer.

[0047] S4. Turn valve 3 to port 9 and use pump 0 to draw 20ml of pure water. Then turn valve 3 to port 10 and use pump 0 to discharge 20ml of liquid. Repeat this step 3 times to clean pump 0.

[0048] S5. Turn valve 2 to port 8 and use pump 1 to draw 1.25 ml of 0.2 mol / L Fe(NO3)3·9H2O solution.

[0049] S6. Turn valve 2 to port 6 and use pump 1 to push 1.25 ml of liquid into the mixer to mix the two metal salt solutions.

[0050] S7. Turn valve 2 to port 9 and use pump 1 to draw 20ml of pure water. Then turn valve 2 to port 10 and use pump 0 to discharge 20ml of liquid. Repeat this step 3 times to clean pump 1.

[0051] S8. Turn valve 3 to port 9 and use pump 0 to draw 15ml of pure water. Turn valve 3 to port 2 and use pump 0 to discharge 15ml of pure water into the synthesis tube.

[0052] S9. Repeat the operation in step S8. S10. Turn valve 3 to port 8, use pump 0 to draw 1 ml of solution containing 1 g / 100 ml NaOH and 0.2 mol / L Na2CO3, turn valve 3 to port 2, and use pump 0 to discharge 1 ml of alkaline solution into the synthesis tube to provide an alkaline environment before the double drop.

[0053] S11. Turn valve 3 to port 8 and use pump 0 to draw 20 ml of a solution containing 1 g / 100 ml NaOH and 0.2 mol / L Na2CO3.

[0054] S12. Turn valve 2 to port 9 and use pump 1 to draw 15ml of pure water. Then turn valve 2 to port 6 and use pump 1 to drain the liquid into the mixing tube.

[0055] S13. Turn valve 2 to port 6 and use pump 1 to extract 20ml of salt solution from the mixing tube.

[0056] S14. Turn valve 3 to port 2, and valve 2 to port 2. Using pumps 0 and 1, add the alkaline solution and salt solution dropwise into the synthesizer at a rate of 1 ml / min. Turn on the stirrer and set the stirring speed to 500 rpm. Set the crystallization temperature to room temperature and the duration to 20 min.

[0057] S15. Clean pumps 0 and 1 using the commands in steps 4 and 7.

[0058] S16. Return all pumps and valves to the zero position.

[0059] S17. Centrifuge and wash the product at 60°C. o The sample was obtained by drying at C, and the XRD pattern of the sample is shown below. Figure 6 As shown.

[0060] like Figure 6 As shown, XRD results indicate that MgFe-LDH was successfully synthesized. Example 4

[0061] Automatic synthesis of MgFeAl-LDH - single drop The connection is made using the description in Example 1. The synthesis of the automatic hydrotalcite is controlled by a computer. The automatic control commands are intelligently sent by the computer, and the commands are written without human intervention. The specific command content is as follows.

[0062] S1. Return all pumps and valves to the zero position.

[0063] S2. Turn valve 3 to port 4 and use pump 0 to draw 3.75 ml of 0.2 mol / L Mg(NO3)2·6H2O solution.

[0064] S3. Turn valve #3 to port #6 and use pump #0 to push 3.75ml of liquid into the mixer.

[0065] S4. Turn valve 3 to port 9 and use pump 0 to draw 20ml of pure water. Then turn valve 3 to port 10 and use pump 0 to discharge 20ml of liquid. Repeat this step 3 times to clean pump 0.

[0066] S5. Turn valve 3 to port 5 and use pump 0 to draw 0.625 ml of 0.2 mol / L Al(NO3)3·9H2O solution. S6. Turn valve #3 to port #6 and use pump #0 to push 0.625ml of liquid into the mixer.

[0067] S7. Use the command from step S4 to clean pump #0. S8. Turn valve 2 to port 8 and use pump 1 to draw 0.625 ml of 0.2 mol / L Fe(NO3)3·9H2O solution.

[0068] S9. Turn valve #2 to port #6 and use pump #1 to dispense 0.625 ml of liquid into the mixer. S10. Turn valve 2 to port 9 and use pump 1 to draw 20ml of pure water. Then turn valve 2 to port 10 and use pump 0 to discharge 20ml of liquid. Repeat this step 3 times to clean pump 1.

[0069] S11. Turn valve 3 to port 8 and use pump 0 to draw 20 ml of a solution containing 1 g / 100 ml NaOH and 0.2 mol / L Na2CO3. Turn valve 3 to port 6 and use pump 1 to push 20 ml of alkaline solution into the mixer.

[0070] S12. Turn valve 2 to port 9 and use pump 1 to draw 15ml of pure water. Then turn valve 2 to port 6 and use pump 1 to drain the liquid into the mixing tube.

[0071] S13. Turn valve 2 to port 6 and use pump 1 to extract 20ml of salt solution from the mixing tube.

[0072] S14. Turn valve 3 to port 2, use pump 0 to drop the salt solution into the synthesizer at a rate of 1 ml / min, turn on the stirrer, set the stirring speed to 500 rpm, the crystallization temperature to room temperature, and the duration to 20 min.

[0073] S15. Use the commands in steps 4 and 10 to clean pumps 0 and 1.

[0074] S16. Centrifuge and wash the product at 60°C. o The sample was obtained by drying at C, and the XRD pattern of the sample is shown below. Figure 7 As shown.

[0075] like Figure 7 As shown, the XRD results indicate that the (110) peak position of MgFeAl-LDH shifts to the left compared to MgAl-LDH, proving that MgFeAl-LDH was successfully synthesized. Example 5

[0076] The synthesized binary and ternary hydrotalcites were used to remove nickel, a heavy metal, from electroplating wastewater. First, 30 mg of MgFe-LDH was placed in a beaker and then added to 30 mL of nickel-containing electroplating waste liquid. The mixture was magnetically stirred to ensure uniform dispersion. After 24 hours, 1 mL of the solution was collected, and the concentration of heavy metal ions was monitored. The concentration of metals in the supernatant was then determined using ICP-OES. The mineralization experiments for MgAl-LDH and MgFeAl-LDH followed the same steps.

[0077] The final result is as follows Figure 8 As shown, the three automatically synthesized hydrotalcites, MgFe-LDH, MgAl-LDH, and MgFeAl-LDH, all exhibited good adsorption performance for Ni. MgFeAl-LDH showed particularly good adsorption performance for Ni. 2+ Its adsorption capacity can reach 208.15 mgg. -1 .

[0078] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A system for the automated synthesis of binary and ternary layered double hydroxides, characterized in that: It includes a control module, a signal receiving module, a solution mixing module, an automatic pump module, an automatic valve module, a reaction module, and a power supply; among which, The control module is configured to send a synthesis command to the signal receiving module; The signal receiving module is configured to receive and process the instructions, and send control signals to the automatic pump module, automatic valve module, solution mixing module and reaction module; The automatic valve module has an intermediate interface and multiple peripheral interfaces. The intermediate interface is connected to the automatic pump module, and the peripheral interfaces can be connected to a solution source, a solution mixing module, or a reaction module. The automatic pump module is configured to draw in or discharge liquid upon receiving a control signal.

2. The system for automated synthesis of binary and ternary layered double hydroxides as described in claim 1, characterized in that: The intermediate interface of the automatic valve module can be connected to any external interface through control.

3. The system for automated synthesis of binary and ternary layered double hydroxides as described in claim 1, characterized in that: The material transfer includes: The automatic valve module opens the external interface connecting to the target solution, allowing the automatic pump module to draw in the solution; The automatic valve module opens the external interface connecting the solution mixing module or reaction module, causing the automatic pump module to discharge liquid into the solution mixing module or reaction module.

4. The system for automated synthesis of binary and ternary layered double hydroxides as described in claim 1, characterized in that: The system is configured to control material transfer via signal transmission, and the signal transmission path includes: control module → signal receiving module → automatic pump module / automatic valve module / solution mixing module / reaction module.

5. The system for automated synthesis of binary and ternary layered double hydroxides as described in claim 1, characterized in that: The specific chemical formula of the synthesized hydrotalcite material is [M 2+ 1-x M 3+ x (OH)2] x+ ·(A n- ) (x / n) ·mH2O, where M 2+ It is Mg 2+ Co 2+ Ni 2+ or Zn 2+ At least one of them; M 3+ It is Fe 3+ V 3+ Cr 3+ Mn 3+ At least one of them, 0.2≤x≤0.33, A n- It is NO3 - Cl - or CO3 2- n is the valence of the anion; m is the amount of water of crystallization, ranging from 0.5 to 9. By precisely controlling the synthesis method, different binary and ternary hydrotalcites can be synthesized.

6. A method for the automated synthesis of binary and ternary layered double hydroxides, characterized in that: The preparation of binary and / or ternary hydrotalcites is achieved based on the system described in any one of claims 1-5.

7. The method for automated synthesis of binary and ternary layered double hydroxides as described in claim 6, characterized in that: Includes the following steps: (a) Prepare a mixed solution of divalent and trivalent metal salts with a total concentration of 0.01-1.00 mol / L and place it in a salt solution bottle; (b) Prepare an alkaline solution with a concentration of 0.01-0.2 g / ml and place it in an alkaline solution bottle; (c) Prepare an additive solution with a concentration of 0.01-1 mol / L and place it in an additive solution bottle; (d) The mixed solution is drawn into the mixer through the automatic pump module and the automatic valve module to form solution A with a molar ratio of divalent to trivalent metal ions of 2.0-4.0; (e) 1-400 ml of alkaline solution is drawn through the automatic pump module and the automatic valve module to form solution B; (f) Extract 1-400ml of additive solution through the automatic pump module and automatic valve module to form solution C; (g) Perform any of the following operations: (i) Single drop method: Add solution A dropwise to the mixture of solution B and solution C at a rate of 0.01-10 ml / min, while stirring at a rate of 0-1000 rpm; (ii) Double drop method: The mixture of solution A, solution B, and solution C is simultaneously dropped into the reaction module at a rate of 0.01-10 ml / min, and the stirring rate is 0-1000 rpm; (h) Crystallize the reaction solution at 25-100℃ for 0-24 hours; (i) Filter or centrifuge washing to obtain hydrotalcite material.

8. The method for automated synthesis of binary and ternary layered double hydroxides as described in claim 7, characterized in that: The divalent metal salt is selected from salts of Mg, Zn, Ca, Mn, Fe, Co, Ni, and Cu; The trivalent metal salt is selected from salts of Al, Cr, Fe, In, and Rh; The alkaline solution is NaOH, sodium carbonate, ammonia, urea, or hexamethylenetetramine solution; The additive is formamide, ammonium fluoride, boric acid, sodium dodecyl sulfate, or tris(hydroxymethyl)aminomethane.

9. The method for automated synthesis of binary and ternary layered double hydroxides as described in claim 7, characterized in that: In step (d), Ti is further incorporated. 4+ ,Rh 3+ Or Ru 3+ Metal salt solution.

10. The method for automated synthesis of binary and ternary layered double hydroxides as described in claim 7, characterized in that: The automatic valve module is connected to the automatic pump module through an intermediate interface, and to a solution source, mixer, or reaction module through an external interface; the solution transfer is controlled by switching the interface path.

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