Preparation method and system of ZIF derived carbon carrier based on organic ligand double circulation

Abstract

The invention relates to the field of carbon carrier synthesis, in particular to a preparation method and system of a ZIF derived carbon carrier based on organic ligand double circulation. The preparation method comprises the following steps: S1, uniformly mixing zinc acetate and water to obtain a first mixed solution; s2, determining the mass of 2-methylimidazole supplementary powder, and uniformly mixing the ZIF circulating mother liquor obtained by the previous synthesis, at least optional 2-methylimidazole circulating powder obtained by the previous synthesis and the 2-methylimidazole supplementary powder to obtain a second mixed solution; s3, mixing and reacting the first mixed solution and the second mixed solution, and performing solid-liquid separation to obtain ZIF circulating mother liquor; s5, heating a ZIF filter cake obtained by solid-liquid separation to 270-400 DEG C under the protection of an inert atmosphere, keeping the constant temperature for 2 hours, and collecting 2-methylimidazole circulating powder; and S6, continuously heating the ZIF filter cake to 800-1000 DEG C, and keeping the constant temperature for 2 hours to obtain the ZIF derived carbon carrier.

Description

Technical Field

[0001] The present application relates to the field of carbon carrier synthesis, and in particular, to a method and system for preparing a ZIF-derived carbon carrier based on a double cycle of an organic ligand. Background Art

[0002] Among many nanomaterials, zeolitic imidazole organic framework materials (ZIF) and their derivatives have large specific surface areas, unique nanostructures, and excellent electrochemical properties. Therefore, they are widely used in new energy fields such as medicine, chemical separation, energy storage, supercapacitors, and fuel cells. Researchers have shown great enthusiasm for ZIF materials, and the number of research papers has increased nearly 10 times in ten years. However, there are no commercial production and application cases of ZIF materials on the market, which also indirectly reflects the problems of high production costs and poor material consistency of ZIF materials.

[0003] With the continuous advancement of nanomaterial synthesis technology, researchers have tried to develop new ZIF synthesis technologies such as ultrasound-assisted synthesis, microwave method, accelerated aging method, and solvent injection method in recent years. However, compared with nanomaterial synthesis technology, the material separation and purification process of ZIF has received less attention. First, the synthesized ZIF materials are generally small in size (50-500nm). As the output increases, the traditional filtration separation technology has a low separation efficiency and is an important rate-limiting step in the ZIF synthesis process. Secondly, since the reaction mother liquor obtained in the separation process contains a large amount of unreacted 2-methylimidazole ligands, direct discharge will lead to waste of raw materials and increase in wastewater treatment costs. In addition, since ZIF has a rich microporous structure and can adsorb a large amount of 2-methylimidazole ligands, it will also cause ligand waste, high organic content, and environmental pollution during pyrolysis.

[0004] In view of this, this application is hereby filed. Summary of the invention

[0005] The purpose of the present application is to provide a method and system for preparing a ZIF-derived carbon carrier based on a double circulation of an organic ligand, so as to solve the problems of waste of 2-methylimidazole ligands and high cost of wastewater and waste gas treatment in the prior art.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions: In a first aspect, the present application provides a method for preparing a ZIF-derived carbon carrier based on a double cycle of an organic ligand, comprising: S1, mixing zinc acetate and water uniformly to obtain a first mixed solution; S2. Determine the mass of the 2-methylimidazole supplementary powder according to the mass of the zinc acetate powder, and mix the ZIF circulating mother liquor obtained in the previous synthesis and the 2-methylimidazole supplementary powder to obtain a second mixed solution; Or, the mass of the 2-methylimidazole supplementary powder is determined according to the mass of the ZIF filter cake obtained in the previous synthesis and the mass of the 2-methylimidazole circulating powder obtained in at least the previous synthesis, and the ZIF circulating mother liquor obtained in the previous synthesis, the 2-methylimidazole circulating powder and the 2-methylimidazole supplementary powder are uniformly mixed to obtain a second mixed solution; S3, transferring the first mixed solution and the second mixed solution to a reaction separator for mixed reaction; S4, increasing the pressure of the reaction separator to achieve solid-liquid separation and obtain ZIF circulating mother liquor; S5, heating the ZIF filter cake obtained by solid-liquid separation to 270-400° C. under the protection of an inert atmosphere, maintaining the temperature for 2 hours, and collecting 2-methylimidazole circulating powder; S6. Continue heating the ZIF filter cake to 800-1000° C. and keep the temperature constant for 2 hours to obtain a ZIF-derived carbon carrier.

[0007] In some technical solutions, determining the mass of the 2-methylimidazole supplementary powder according to the mass of the zinc acetate powder includes: The mass of 2-methylimidazole supplement powder was calculated using the following formula: W 补充 =1.49×W 醋酸锌 ; Among them, W 补充 is the mass of 2-methylimidazole supplemented powder, W 醋酸锌 is the mass of zinc acetate powder.

[0008] In some technical solutions, the mass of the 2-methylimidazole supplementary powder is determined according to the mass of the ZIF filter cake obtained in the previous synthesis and the mass of the 2-methylimidazole circulating powder obtained in at least the previous synthesis, including: The mass of 2-methylimidazole supplement powder was calculated using the following formula: W 补充 =(W ZIF滤饼 -W 2-甲基咪唑循环粉体 )×71%; among which, W 补充 is the mass of 2-methylimidazole supplemented powder, W ZIF滤饼 is the mass of the ZIF filter cake obtained in the previous synthesis, W 2-甲基咪唑循环粉体 It is the mass of 2-methylimidazole circulating powder obtained from at least the previous synthesis.

[0009] In some technical solutions, the mixing reaction time in S3 is 2-8 hours.

[0010] In some technical solutions, the pressure of the reaction separator in S4 is 4-6 bar.

[0011] In some technical schemes, in S4, ammonia water is used to adjust the pH value of the liquid obtained by solid-liquid separation to 7-10 to obtain a ZIF circulating mother liquor.

[0012] In a second aspect, the present application provides a preparation system for realizing the above-mentioned ZIF-derived carbon carrier preparation method based on double circulation of organic ligands, comprising: a first mixer, a first centrifugal pump, a reaction separator, a second mixer, a second centrifugal pump and an atmosphere furnace; The first mixer, the first centrifugal pump, the reaction separator, the second mixer, the second centrifugal pump and the reaction separator are connected in sequence; The reaction separator, the atmosphere furnace and the reaction separator are connected in sequence; The first mixer is used to mix zinc acetate and water; The atmosphere furnace is used to heat the ZIF filter cake; The second mixer is used to store ZIF circulating mother liquid.

[0013] In some technical solutions, a porous nickel foam filter column is provided at the gas outlet of the atmosphere furnace.

[0014] In some technical solutions, there are two reaction separators.

[0015] Compared with the prior art, the beneficial effects of this application are: (1) Compared with the prior art, the present application adds a second circulating logistics (2-methylimidazole powder circulation). Based on the different boiling points between ZIF particles and 2-methylimidazole, 2-methylimidazole can be recovered by high-temperature heat treatment, which significantly improves the effective utilization rate of organic ligands and reduces the synthesis cost.

[0016] (2) This application adopts a dual circulation technology, in which the ZIF mother liquor circulation reduces the discharge of wastewater containing 2-methylimidazole; the ligand powder circulation reduces the content of organic matter in the pyrolysis tail gas. The synergistic effect of the two is beneficial to protecting the environment and reducing the cost of waste treatment.

[0017] (3) Based on the principles of membrane separation and positive pressure filtration, this application introduces a reaction-separation integrated design into the process flow of ZIF synthesis for the first time. There is no need to replace equipment during the reaction and separation processes, thereby improving the efficiency of ZIF synthesis and separation.

[0018] (4) The present application can be applied to both intermittent and continuous methods for synthesizing ZIF-derived carbon carriers to improve synthesis efficiency. The intermittent method is to synthesize the ZIF-derived carbon carriers for the first time before synthesizing them for the second time, while the continuous method is to synthesize the ZIF-derived carbon carriers for the second time during the first synthesis (such as after solid-liquid separation). BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 It is a schematic flow chart of the method for preparing a ZIF-derived carbon carrier based on double circulation of organic ligands provided in the present application; Figure 2 The structure of the ZIF-derived carbon carrier preparation system based on double circulation of organic ligands provided in this application and the corresponding material flow diagram; Figure 3 SEM image of the sample synthesized for the first time in Example 2; Figure 4 SEM image of the sample obtained by the second synthesis of Example 2; Figure 5 SEM image of the sample synthesized for the first time in Example 1; Figure 6 SEM image of the sample obtained by the second synthesis in Example 1; Figure 7 Example 2 XRD curves of ZIF synthesized for the first time and the fourth time. DETAILED DESCRIPTION

[0021] The following is a description of exemplary embodiments of the present application in conjunction with the accompanying drawings, including various details of the embodiments of the present application to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description.

[0022] As mentioned in the background technology, the existing technology has the problem of waste of 2-methylimidazole ligands and high waste gas (liquid) treatment costs. In this regard, the present application couples the ZIF synthesis reaction and separation process, designs a new organic ligand recycling process, and maximizes the recovery of unreacted 2-methylimidazole ligands, thereby achieving improved synthesis efficiency, reduced raw material costs, and reduced waste gas (liquid) treatment costs.

[0023] As one aspect of this application, Figure 1 As shown, the present application provides a method for preparing a ZIF-derived carbon carrier based on a double cycle of an organic ligand, comprising the following steps: S1. Mix zinc acetate and water evenly to obtain a first mixed solution.

[0024] S2. Determine the mass of the 2-methylimidazole supplementary powder according to the mass of the zinc acetate powder, and mix the ZIF circulating mother liquor obtained in the previous synthesis and the 2-methylimidazole supplementary powder to obtain a second mixed solution; Alternatively, the mass of the 2-methylimidazole supplementary powder is determined based on the mass of the ZIF filter cake obtained in the previous synthesis and the mass of the 2-methylimidazole circulating powder obtained in at least the previous synthesis, and the ZIF circulating mother liquor obtained in the previous synthesis, the 2-methylimidazole circulating powder and the 2-methylimidazole supplementary powder are evenly mixed to obtain a second mixed solution.

[0025] Wherein, the mass of the ZIF filter cake is the mass of the dried ZIF filter cake, and the ZIF filter cake contains unreacted 2-methylimidazole. The 2-methylimidazole circulating powder obtained by at least the previous synthesis includes the 2-methylimidazole circulating powder obtained by the previous synthesis, the 2-methylimidazole circulating powder obtained by the previous two syntheses, ..., the 2-methylimidazole circulating powder obtained by the previous N syntheses, N being greater than or equal to 3. In the present application, when the supplemented 2-methylimidazole circulating powder is obtained by the previous synthesis, the process is intermittent or continuous, and when the supplemented 2-methylimidazole circulating powder is obtained by more than the previous two times, the process is continuous, that is, when a continuous process is adopted, a certain amount of 2-methylimidazole circulating powder is first collected and then recycled.

[0026] In an optional embodiment, determining the mass of the 2-methylimidazole supplementary powder according to the mass of the zinc acetate powder comprises: The mass of 2-methylimidazole supplement powder was calculated using the following formula: W 补充 =1.49×W 醋酸锌 ; Among them, W 补充 is the mass of 2-methylimidazole supplemented powder, W 醋酸锌 is the mass of zinc acetate powder.

[0027] In an optional embodiment, the method of determining the mass of the 2-methylimidazole supplementary powder according to the mass of the ZIF filter cake obtained in the previous synthesis and the mass of the 2-methylimidazole circulating powder obtained in at least the previous synthesis comprises: The mass of 2-methylimidazole supplement powder was calculated using the following formula: W 补充 =(W ZIF滤饼 -W2-甲基咪唑循环粉体 )×71%; among which, W 补充 is the mass of 2-methylimidazole supplemented powder, W ZIF滤饼 is the mass of the ZIF filter cake obtained in the previous synthesis, W 2-甲基咪唑循环粉体 It is the mass of 2-methylimidazole circulating powder obtained from at least the previous synthesis.

[0028] S3, transferring the first mixed solution and the second mixed solution to a reaction separator for mixed reaction.

[0029] Optionally, the mixing reaction time is 2-8 hours, for example 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, 7.5 hours or 8 hours.

[0030] S4, increasing the pressure of the reaction separator to achieve solid-liquid separation and obtain a ZIF circulating mother liquor.

[0031] Optionally, the pressure of the reaction separator in S4 is 4-6 bar, for example, 4 bar, 5 bar or 6 bar.

[0032] Optionally, in S4, the pH value of the liquid obtained by solid-liquid separation is adjusted to 7-10 using aqueous ammonia to obtain a ZIF circulating mother liquor, wherein the pH value is, for example, 7, 8, 9 or 10.

[0033] S5. The ZIF filter cake obtained by solid-liquid separation is heated to 270-400° C. under the protection of an inert atmosphere, maintained at a constant temperature for 2 hours, and 2-methylimidazole circulating powder is collected.

[0034] When the ZIF filter cake is heated to 270-400°C under the protection of an inert atmosphere and kept at a constant temperature for 2 hours, 2-methylimidazole can be vaporized, thereby separating 2-methylimidazole from the main components of ZIF. After 2-methylimidazole is vaporized and cooled, it is further solidified to form 2-methylimidazole circulating powder.

[0035] Optionally, the heating temperature in S5 is, for example, 270° C., 280° C., 290° C., 300° C., 310° C., 320° C., 330° C., 340° C., 350° C., 360° C., 370° C., 380° C., 390° C. or 400° C. When the heating temperature is between 270° C. and 400° C., the evaporation rate of 2-methylimidazole is relatively faster.

[0036] S6. Continue heating the ZIF filter cake to 800-1000° C. and keep the temperature constant for 2 hours to obtain a ZIF-derived carbon carrier.

[0037] Wherein, the heating temperature includes but is not limited to 800°C, 820°C, 840°C, 850°C, 860°C, 880°C, 900°C, 920°C, 940°C, 950°C, 960°C, 980°C or 1000°C.

[0038] The above method has the following advantages: (1) Compared with the prior art, the present application adds a second circulating material flow (2-methylimidazole circulating powder). Based on the different boiling points between ZIF particles and 2-methylimidazole, 2-methylimidazole can be recovered by high-temperature heat treatment, which significantly improves the effective utilization rate of organic ligands and reduces the synthesis cost.

[0039] (2) This application adopts a dual circulation technology, in which the ZIF mother liquor circulation reduces the discharge of wastewater containing 2-methylimidazole; the ligand powder circulation reduces the content of organic matter in the pyrolysis tail gas. The synergistic effect of the two is beneficial to protecting the environment and reducing the cost of waste treatment.

[0040] (3) Based on the principles of membrane separation and positive pressure filtration, this application introduces a reaction-separation integrated design into the process flow of ZIF synthesis for the first time. There is no need to replace equipment during the reaction and separation processes, thereby improving the efficiency of ZIF synthesis and separation.

[0041] (4) The present application can be applied to both intermittent and continuous methods for synthesizing ZIF-derived carbon carriers to improve synthesis efficiency. The intermittent method is to synthesize the ZIF-derived carbon carriers for the first time before synthesizing them for the second time, while the continuous method is to synthesize the ZIF-derived carbon carriers for the second time during the first synthesis (such as after solid-liquid separation).

[0042] As another aspect of this application, Figure 2 As shown, the present application provides a preparation system for the above-mentioned ZIF-derived carbon carrier preparation method based on double circulation of organic ligands, comprising: a first mixer 1, a first centrifugal pump 2, a reaction separator 3, a second mixer 4, a second centrifugal pump 5 and an atmosphere furnace 6; The first mixer 1, the first centrifugal pump 2, the reaction separator 3, the second mixer 4, the second centrifugal pump 5 and the reaction separator 3 are connected in sequence; The reaction separator 3, the atmosphere furnace 6 and the reaction separator 3 are connected in sequence; Mixer 1 is used for mixing zinc acetate and water; The atmosphere furnace 6 is used to heat the ZIF filter cake; The second mixer 4 is used to store the ZIF circulating mother liquid.

[0043] In an optional embodiment, a porous nickel foam filter column is provided at the gas outlet of the atmosphere furnace. Providing a porous nickel foam filter column at the gas outlet can increase the cooling area and further improve the recovery rate of 2-methylimidazole powder.

[0044] In an optional embodiment, there are two reaction separators. In this embodiment, two reaction separators are provided, and after the first synthesis is completed using one of the reaction separators, the second synthesis can be started using the other reaction separator, and the first reaction separator is cleaned at the same time, and the two reaction separators are used alternately.

[0045] The present application is described in detail below with reference to embodiments.

[0046] Example 1 (1) 21 g of anhydrous zinc acetate S-1 and 30 L of distilled water S-2 are respectively introduced into the first mixer 1 and stirred evenly.

[0047] (2) A mixed solution S-3 containing 370 g of 2-methylimidazole and 70 L of distilled water was introduced into the first reaction separator 3-1 and mixed uniformly. The mixed solution S-4 in the mixer 1 was transferred to the first reaction separator 3-1 by the first centrifugal pump 2. The above reaction solution was stirred at a speed of 300 rpm for 6 hours.

[0048] (3) After the reaction is completed, the pressure of the first reaction separator 3-1 is increased to 4 bar, and solid-liquid separation is achieved through the microfiltration membrane at the bottom of the first reaction separator 3-1. The filtered liquid S-10 is transferred to the second mixer 4, and the pH value is adjusted to 11 by adding ammonia water S-11 to obtain a circulating material 1 (ZIF circulating mother liquor S-5), which is transferred to the second reaction separator 3-2 through the second centrifugal pump 5.

[0049] (4) The ZIF filter cake S-6 obtained by filtration was dried overnight at 60°C and weighed to be 35 g.

[0050] (5) The ZIF filter cake was transferred to the atmosphere furnace 6, and the temperature was raised to 300 °C under the protection of the inert atmosphere S-7, and the temperature was kept constant for 2 hours. The recycled material II (2-methylimidazole recycled powder S-9) weighing 15 g was collected from the gas outlet, and the temperature was further raised to 800 °C and the temperature was kept constant for 2 hours to obtain the ZIF-derived carbon carrier S-8.

[0051] Example 2 (1) 21 g of anhydrous zinc acetate S-1 and 0.5 L of distilled water S-2 are respectively introduced into the first mixer 1 and stirred evenly.

[0052] (2) 14.2 g of supplementary 2-methylimidazole powder S-3 and 15 g of recycled material 2 (2-methylimidazole recycled powder S-9) were added to the second reaction separator 3-2, and at the same time, recycled material 1 (ZIF recycled mother liquor S-5) was introduced into the second reaction separator 3-2.

[0053] (3) The mixed solution S-4 in the first mixer 1 is transferred to the second reaction separator 3-2 by the first centrifugal pump 2, and the reaction solution is stirred at a speed of 300 rpm for 4 hours.

[0054] (4) After the reaction is completed, the pressure of the second reaction separator 3-2 is increased to 6 bar, and solid-liquid separation is achieved through the microfiltration membrane at the bottom of the second reaction separator 3-2. The filtered liquid S-10 is transferred to the second mixer 4, and the pH value is adjusted to 10 by adding ammonia water S-11 to obtain a circulating material 1 (ZIF circulating mother liquor S-5), which is transferred to the first reaction separator 3-1 through the second centrifugal pump 5.

[0055] (5) The ZIF filter cake S-6 obtained by filtration weighed 33 g after high-temperature drying.

[0056] (6) The ZIF filter cake was transferred to an atmosphere furnace 6, and the temperature was raised to 270 °C under the protection of an inert atmosphere S-7. The temperature was maintained constant for 2 hours, and the recycled material II (2-methylimidazole recycled powder S-9) obtained at the gas outlet was collected. The weight of the recycled material was 13 g.

[0057] (7) The temperature of the un-volatilized sample in atmosphere furnace 6 was further raised to 900 °C and kept at this temperature for 2 hours to obtain the ZIF-derived carbon support S-8.

[0058] (8) Repeat steps 1 to 4, using the first reaction separator 3-1 and the second reaction separator 3-2 alternately to obtain a second synthesized ZIF sample.

[0059] Example 3 (1) 25 g of anhydrous zinc acetate S-1 and 0.5 L of distilled water S-2 are respectively introduced into the first mixer 1 and stirred evenly.

[0060] (2) 17.75 g of 2-methylimidazole supplementary powder S-3 and 10 g of recycled material 2 (2-methylimidazole recycled powder S-9) were added to the second reaction separator 3-2, and the recycled material 1 (ZIF recycled mother liquor S-5) was introduced into the second reaction separator 3-2.

[0061] (3) The mixed solution S-4 in the first mixer 1 is transferred to the second reaction separator 3-2 by the first centrifugal pump 2, and the reaction solution is stirred at a speed of 300 rpm for 3 hours.

[0062] (4) After the reaction is completed, the pressure of the second reaction separator 3-2 is increased to 4 bar, solid-liquid separation is achieved through the microfiltration membrane at the bottom of the second reaction separator 3-2, and the filtered liquid S-10 is transferred to the second mixer 4. The pH value is adjusted to 9 by adding ammonia water S-11 to obtain a circulating material 1 (ZIF circulating mother liquor S-5), which is transferred to the first reaction separator 3-1 through the second centrifugal pump 5.

[0063] (5) The ZIF filter cake S-6 obtained by filtration was dried at 80°C and weighed to be 35 g.

[0064] (6) The obtained filter cake was transferred to the atmosphere furnace 6, and the temperature was raised to 270 °C under the protection of the inert atmosphere S-7. The temperature was kept constant for 2 hours, and the gas outlet circulating material 2 (2-methylimidazole circulating powder S-9) was collected and weighed to be 10 g.

[0065] (7) The non-volatile components were heated to 1000 °C and kept at this temperature for 2 h to obtain the ZIF-derived carbon support S-8.

[0066] (8) Repeat steps 1 to 4, and use the first reaction separator 3-1 and the first reaction separator 3-2 alternately twice to obtain a total of three batches of ZIF samples.

[0067] from Figure 3-Figure 7 It can be seen that different batches of cycles can synthesize polyhedral ZIF nanoparticles. Among them, the size of ZIF particles in each batch is relatively uniform. By comparing the XRD data of the powder synthesized for the first time and the fourth time, it can be seen that the obtained samples have obvious ZIF structure and high crystallinity.

[0068] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this application can be executed in parallel, sequentially or in different orders, as long as the expected results of the technical solution disclosed in this application can be achieved, and this document is not limited here.

[0069] The above specific implementations do not constitute a limitation on the protection scope of this application. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application should be included in the protection scope of this application.

Claims

1. A method for preparing a ZIF-derived carbon carrier based on double circulation of organic ligands, characterized in that: include: S1, mixing zinc acetate and water uniformly to obtain a first mixed solution; S2. Determine the mass of the 2-methylimidazole supplementary powder according to the mass of the zinc acetate powder, and mix the ZIF circulating mother liquor obtained in the previous synthesis and the 2-methylimidazole supplementary powder to obtain a second mixed solution; Or, the mass of the 2-methylimidazole supplementary powder is determined according to the mass of the ZIF filter cake obtained in the previous synthesis and the mass of the 2-methylimidazole circulating powder obtained in at least the previous synthesis, and the ZIF circulating mother liquor obtained in the previous synthesis, the 2-methylimidazole circulating powder and the 2-methylimidazole supplementary powder are uniformly mixed to obtain a second mixed solution; S3, transferring the first mixed solution and the second mixed solution to a reaction separator for mixed reaction; S4, increasing the pressure of the reaction separator to achieve solid-liquid separation and obtain a ZIF circulating mother liquor; S5, heating the ZIF filter cake obtained by solid-liquid separation to 270-400° C. under the protection of an inert atmosphere, maintaining the temperature for 2 hours, and collecting 2-methylimidazole circulating powder; S6. Continue heating the ZIF filter cake to 800-1000° C. and keep the temperature constant for 2 hours to obtain a ZIF-derived carbon carrier.

2. The method for preparing a ZIF-derived carbon carrier based on double circulation of organic ligands according to claim 1, characterized in that: The method of determining the mass of the 2-methylimidazole supplementary powder according to the mass of the zinc acetate powder comprises: The mass of 2-methylimidazole supplement powder was calculated using the following formula: W 补充 =1.49×W 醋酸锌 ; Among them, W 补充 is the mass of 2-methylimidazole supplemented powder, W 醋酸锌 is the mass of zinc acetate powder.

3. The method for preparing a ZIF-derived carbon carrier based on double circulation of organic ligands according to claim 1, characterized in that: The method of determining the mass of the 2-methylimidazole supplementary powder according to the mass of the ZIF filter cake obtained in the previous synthesis and the mass of the 2-methylimidazole circulating powder obtained in at least the previous synthesis comprises: The mass of 2-methylimidazole supplement powder was calculated using the following formula: W 补充 =(W ZIF滤饼 -W 2-甲基咪唑循环粉体 )×71%; among which, W 补充 is the mass of 2-methylimidazole supplemented powder, W ZIF滤饼 is the mass of the ZIF filter cake obtained in the previous synthesis, W 2-甲基咪唑循环粉体 It is the mass of 2-methylimidazole circulating powder obtained from at least the previous synthesis.

4. According to the method for preparing a ZIF-derived carbon carrier based on double circulation of organic ligands according to claim 1, the time of the mixing reaction in S3 is 2-8 hours.

5. According to the method for preparing ZIF-derived carbon carrier based on double circulation of organic ligands according to claim 1, the pressure of the reaction separator in S4 is 4-6 bar.

6. According to the method for preparing a ZIF-derived carbon carrier based on double circulation of organic ligands in claim 1, in said S4, ammonia water is used to adjust the pH value of the liquid obtained by solid-liquid separation to 7-10 to obtain a ZIF circulating mother liquor.

7. A preparation system for realizing the preparation method of ZIF-derived carbon carrier based on double circulation of organic ligands according to any one of claims 1 to 6, characterized in that: include: A first mixer, a first centrifugal pump, a reaction separator, a second mixer, a second centrifugal pump and an atmosphere furnace; The first mixer, the first centrifugal pump, the reaction separator, the second mixer, the second centrifugal pump and the reaction separator are connected in sequence; The reaction separator, the atmosphere furnace and the reaction separator are connected in sequence; The first mixer is used to mix zinc acetate and water; The atmosphere furnace is used to heat the ZIF filter cake; The second mixer is used to store ZIF circulating mother liquid.

8. The preparation system according to claim 7, characterized in that: A porous nickel foam filter column is arranged at the gas outlet of the atmosphere furnace.

9. The preparation system according to claim 7, characterized in that: There are two reaction separators.

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