Preparation method and production equipment of heteroatom-doped magnetic carbon material

Abstract

The invention discloses a preparation method and production equipment of a heteroatom-doped magnetic carbon material, and the method comprises the following steps: 1, uniformly mixing a raw material with a metallocene catalyst to obtain a mixture, and uniformly dispersing the mixture in a closed reaction kettle; 2, after the closed reaction kettle is completely sealed, inert protective gas is introduced; and 3, carrying out heat treatment, naturally cooling to room temperature, and taking out a product, namely the heteroatom-doped magnetic carbon material. The production equipment comprises a closed reaction kettle and a heteroatom addition tank, the closed reaction kettle comprises a reaction kettle body and an equipment box body; a thermal insulation system is mounted on the outer wall of the reaction kettle body, and a temperature control system is mounted on the equipment box body; and the heteroatom addition tank is communicated with the inner cavity of the reaction kettle body through a pipeline. Graphene can be conveniently and rapidly modified, the purpose of stable modification is achieved, and the prepared magnetic carbon material has the advantages of being low in product cost, simple in process, easy to operate, good in repeatability and high in quality.

Description

Technical Field

[0001] The invention relates to the technical field of fine chemical industry, and in particular to a preparation method and production equipment of a heteroatom-doped magnetic carbon material. Background Art

[0002] Magnetic carbon material is mainly a nitrogen-doped magnetic graphene material loaded with carbon-coated magnetic nanoparticles. Graphene is a sp 2 A new material in which hybrid connected carbon atoms are tightly stacked into a single-layer two-dimensional honeycomb lattice structure, with a thickness of about 0.335nm, which is the thinnest material known so far. Graphene has excellent optical, electrical and mechanical properties, and has important application prospects in materials science, energy, biomedicine and drug delivery, and is considered to be a revolutionary material of the future.

[0003] The preparation methods of magnetic carbon materials can currently be summarized into the following five types: co-precipitation method, hydrothermal method, template method, impregnation method and carbonized metal organic framework material method. The co-precipitation method refers to immersing the pre-synthesized carbon material in a magnetic precursor solution, and then depositing the magnetic nanomaterial in situ in the pores of the porous carbon material to synthesize the magnetic carbon material. The hydrothermal method is to first mix the magnetic source and the carbon source in a certain proportion and evenly place them in a high-pressure reactor, and then perform a hydrothermal reaction under high temperature and high pressure conditions to obtain the target product. The template method refers to a type of synthesis method that uses a substance with a specific structure and morphology as a template and a template molecule as the main body to construct the structure and morphology of the material. According to the different templates, it can be divided into soft template, hard template and dual template method. When preparing magnetic carbon materials by the template method, the magnetic precursor can be introduced during or after the synthesis of the carbon material. The impregnation method is relatively simple. The carbon material precursor or biomass powder is directly impregnated in the magnetic source precursor or magnetic nanoparticle dispersion solution. After the solvent is evaporated and dried, it is directly heat treated and then activated to obtain the magnetic carbon material. Metal organic framework materials are a new type of porous material formed by self-assembly of metal ions and organic ligands through coordination bonds. They have developed pores and a high specific surface area. There are both carbon sources and magnetic sources, so direct carbonization of metal organic framework materials has become a new synthesis method for magnetic carbon materials that have emerged in recent years.

[0004] The traditional synthesis equipment and synthesis process mainly have the following disadvantages: the traditional synthesis method is complicated, environmentally polluting, and has a long process (or high raw material cost), resulting in high product cost and not suitable for large-scale production and use; although the nano-Fe3O4 particle and graphene composite material has the dual properties of nano-Fe3O4 particles and graphene, it is closer to the properties of nano-Fe3O4 rather than the properties of graphene, and does not highlight the specificity of graphene; the exposed nano-Fe3O4 particles in the existing magnetic graphene products have high chemical activity, are easily oxidized in the air, and are easily dissolved in weakly acidic solutions, thereby causing the magnetic graphene composite material to lose its magnetism, making it difficult to obtain a stable magnetic graphene material.

[0005] In addition, traditional graphene material preparation methods have a narrow scope of application, and the graphene products produced have single performance. It is impossible to modify and customize the properties of graphene conveniently and quickly, and does not meet existing needs.

[0006] To this end, a preparation method and production equipment of a heteroatom-doped magnetic carbon material are proposed. Summary of the invention

[0007] The object of the present invention is to provide a method for preparing a heteroatom-doped magnetic carbon material and a production device thereof, aiming to solve or improve at least one of the above-mentioned technical problems.

[0008] To achieve the above object, the present invention provides the following scheme: The present invention provides a method for preparing a heteroatom-doped magnetic carbon material, comprising the following steps:

[0009] Step 1: uniformly mix the raw material and the metallocene catalyst to obtain a mixture, and uniformly disperse the mixture in a closed reactor; the raw material is used to provide a carbon source and a nitrogen source at the same time;

[0010] Step 2: After the closed reactor is completely sealed, it is connected to the heteroatom addition tank through a pipeline, and an inert protective gas is introduced into the closed reactor to make the oxygen content in the closed reactor 0% to 22%;

[0011] Step 3: Use a closed reactor to heat treat the uniform mixture, and after it naturally cools to room temperature, take out the product, which is the magnetic carbon material doped with heteroatoms.

[0012] According to a method for preparing a heteroatom-doped magnetic carbon material provided by the present invention, the specific heat treatment conditions in step three are to increase the temperature to 650°C to 1000°C in 1h to 10h, keep the temperature constant for 10min to 10h, and cool the temperature down to 500°C at 1°C / min to 10°C / min.

[0013] According to a method for preparing a heteroatom-doped magnetic carbon material provided by the present invention, the specific operation of step two is to introduce an inert protective gas into the reaction space through the air intake system of the connected heteroatom addition tank or closed reactor, so that the oxygen content of the reaction space is 0% to 22%; the inert protective gas includes argon, nitrogen or helium.

[0014] According to a method for preparing a heteroatom-doped magnetic carbon material provided by the present invention, the raw material is one or a mixture of melamine, urea, thiourea, dicyandiamide, cyanuric acid, carbon trinitrogen tetranitrate;

[0015] The metallocene catalyst is one or a mixture of ferrocene, nickelocene or cobaltocene; the mass ratio of the raw material to the metallocene catalyst is 100:1-100.

[0016] According to a method for preparing a heteroatom-doped magnetic carbon material provided by the present invention, the mass volume ratio of the mixture in step 1 to the internal effective volume of the closed reactor is 1 g / L to 100 g / L, and the accumulation thickness of the mixture in the closed reactor is 0.01 g / cm 2 ~1g / cm 2 .

[0017] According to the method for preparing a heteroatom-doped magnetic carbon material provided by the present invention, in the step 1, a sodium sulfate solution or a calcium silicate ethanol solution is added to the heteroatom addition tank.

[0018] The present invention also provides a production device for heteroatom-doped magnetic carbon materials, comprising: a closed reaction kettle and a heteroatom addition tank;

[0019] The closed reactor comprises a reactor body and an equipment box; the reactor body is installed in the equipment box, and the top of the reactor body extends out of the equipment box, an insulation system is installed on the outer wall of the reactor body, and the insulation system is located outside the equipment box, and the top of the reactor body is detachably connected to a reactor cover through a closed connection device;

[0020] The reactor body is provided with a stirring device, the heteroatom addition tank is provided with a stirring assembly, and the equipment box is provided with a temperature control system; the heteroatom addition tank is connected with the inner cavity of the reactor body through a pipeline.

[0021] According to the present invention, a production device for heteroatom-doped magnetic carbon materials is provided, wherein a safety air pressure protection device and an inlet and exhaust pipe valve system are installed on the reactor cover, and the safety air pressure protection device and the inlet and exhaust pipe valve system are both connected to the inner cavity of the reactor body; the pipeline is fixedly connected and connected to the inlet and exhaust pipe valve system;

[0022] The airtight connection device adopts any one or more of threads, ground joints, graphite sealing strips or flanges.

[0023] According to the present invention, there is provided a production device for heteroatom-doped magnetic carbon materials, wherein the heteroatom addition tank comprises a heteroatom addition tank body, the top of the heteroatom addition tank body is detachably connected to a heteroatom addition tank cover via a heteroatom addition tank flange, the heteroatom addition tank cover is provided with a heteroatom addition tank pressure display gauge, a heteroatom addition tank air inlet valve and a heteroatom addition tank air outlet valve, the heteroatom addition tank pressure display gauge, the heteroatom addition tank air inlet valve and the heteroatom addition tank air outlet valve are all connected to the inner cavity of the heteroatom addition tank body, and the heteroatom addition tank air outlet valve is fixedly connected to and connected to the pipeline;

[0024] The stirring assembly includes a heteroatom addition tank base installed at the bottom of the heteroatom addition tank body, a driving motor is installed on the top of the heteroatom addition tank base, the driving motor is installed at the bottom of the heteroatom addition tank body, the output shaft of the driving motor is installed with a heteroatom addition tank stirring arm, the heteroatom addition tank stirring arm extends into the heteroatom addition tank body, and the heteroatom addition tank internal stirring head is installed on the heteroatom addition tank stirring arm.

[0025] According to the present invention, there is provided a production device for heteroatom-doped magnetic carbon materials, wherein the reactor body has a cylindrical structure, and the heat preservation system comprises a heat preservation and heat insulation material installed on the top of the outer wall of the reactor body;

[0026] The closed connection device comprises two sealing flange bodies, which are respectively fixedly mounted on the reactor body and the reactor cover, and the two sealing flange bodies are detachably connected via a plurality of flange bolts, on which flange nuts are threadedly connected.

[0027] The present invention discloses the following technical effects:

[0028] The present invention uniformly mixes raw materials and metallocene catalysts to obtain a mixture, and uniformly disperses the mixture in a closed reactor. The entire reaction process only requires one time of feeding, which is fast, safe, green and environmentally friendly, and the quality of the produced graphene product is stable.

[0029] During the preparation of the present invention, an inert protective gas is introduced into the closed reactor, so that the oxygen content in the closed reactor is 0% to 22%, thereby avoiding the problem that the magnetic nanoparticles are corroded and weakened due to long-term exposure to the air. In addition, since the magnetic nanoparticles are wrapped by the nanocarbon layer, the prepared magnetic carbon material has better structural stability and chemical stability, is resistant to acid and alkali corrosion, and is resistant to air oxidation, and can have long-term magnetic properties.

[0030] The heteroatom addition tank of the present invention is connected to the inner cavity of the reactor body through a pipeline, and a uniform system of target added heteroatoms can be added to the heteroatom addition tank according to demand, which provides more choices and possibilities for dopants and performance modification of production products. The target heteroatoms are doped into the target product through reaction. Due to the characteristics of graphene, the doping atoms can be doped into the graphene structure, and the graphene can be modified quickly and conveniently to achieve the purpose of stable modification.

[0031] The magnetic carbon material such as magnetic graphene prepared by the preparation method of the present invention has the advantages of low product cost, simple process, easy operation, good repeatability, large-scale production, and high graphene quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is a front view of the closed reactor in the present invention;

[0034] Figure 2 It is a side cross-sectional view of the closed reactor in the present invention;

[0035] Figure 3 It is an axonometric view of the heteroatom addition tank in the present invention;

[0036] Figure 4 It is a schematic diagram of the structure of the heteroatom addition tank in the present invention;

[0037] Figure 5 This is a scanning electron microscope photo of the product of Example 1;

[0038] Figure 6 is the X-ray diffraction pattern of the product of Example 1;

[0039] Figure 7 This is a transmission electron microscope photo of the product of Example 1;

[0040] Figure 8 Magnetic properties of the product in Example 1.

[0041] Among them, 1. Reactor body; 2. Sealing flange body; 3. Insulation system; 4. Equipment box; 5. Temperature control system; 6. Safety air pressure protection device; 7. Inlet and exhaust pipe valve system; 8. Flange bolts; 9. Flange nuts; 10. Reactor cover; 11. Heteroatom addition tank inlet valve; 12. Heteroatom addition tank cover; 13. Heteroatom addition tank flange; 14. Heteroatom addition tank body; 15. Heteroatom addition tank pressure display gauge; 16. Heteroatom addition tank outlet valve; 17. Heteroatom addition tank internal stirring head; 18. Heteroatom addition tank stirring arm; 19. Heteroatom addition tank base. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] Reference Figure 1-Figure 8 The present invention provides a method for preparing a heteroatom-doped magnetic carbon material, comprising the following steps:

[0045] Step 1: uniformly mix the raw material and the metallocene catalyst to obtain a mixture, and uniformly disperse the mixture in a closed reactor; the raw material is used to provide a carbon source and a nitrogen source at the same time;

[0046] Step 2: After the closed reactor is completely sealed, it is connected to the heteroatom addition tank through a pipeline, and an inert protective gas is selectively introduced into the closed reactor to make the oxygen content in the closed reactor 0% to 22%;

[0047] Step 3: heat-treating the uniform mixture in a closed reactor, and taking out the product after the mixture naturally cools to room temperature, which is the magnetic carbon material doped with heteroatoms;

[0048] In this way, the present invention mixes the raw materials and the metallocene catalyst to obtain a mixture, and evenly disperses the mixture in a closed reactor. Only one feeding is required in the entire reaction process, which is fast, safe, green and environmentally friendly, and the quality of the produced graphene product is stable.

[0049] During the preparation of the present invention, an inert protective gas is introduced into the closed reactor, so that the oxygen content in the closed reactor is 0% to 22%, thereby avoiding the problem that the magnetic nanoparticles are corroded and weakened due to long-term exposure to the air. In addition, since the magnetic nanoparticles are wrapped by the nanocarbon layer, the prepared magnetic carbon material has better structural stability and chemical stability, is resistant to acid and alkali corrosion, and is resistant to air oxidation, and can have long-term magnetic properties.

[0050] The heteroatom addition tank of the present invention is connected to the inner cavity of the reactor body through a pipeline, and a uniform system of target added heteroatoms can be added to the heteroatom addition tank according to demand, which provides more choices and possibilities for dopants and performance modification of production products. The target heteroatoms are doped into the target product through reaction. Due to the characteristics of graphene, the doping atoms can be doped into the graphene structure, and the graphene can be modified quickly and conveniently to achieve the purpose of stable modification.

[0051] The magnetic carbon material such as magnetic graphene prepared by the preparation method of the present invention has the advantages of low product cost, simple process, easy operation, good repeatability, large-scale production, and high graphene quality;

[0052] The preparation method of the present invention has the advantages of simple operation, good airtightness, high safety factor, high reaction efficiency, high product quality, controllable product characteristics, large-scale preparation, and controllable parameters such as material specific surface area, product morphology, structure, composition, and magnetic properties, surface functional groups, hydrophilic and hydrophobic properties, and other properties.

[0053] To further optimize the scheme, the specific heat treatment conditions in step three are to raise the temperature to 650°C to 1000°C in 1h to 10h, keep the temperature constant for 10min to 10h, and cool down to 500°C at a rate of 1°C / min to 10°C / min.

[0054] Further optimizing the scheme, the ambient atmosphere with an oxygen content of 0% to 22% can be flexibly adjusted according to the experimental conditions and the properties of the product. The specific operation of step 2 is to introduce an inert protective gas into the reaction space through the air intake system of the connected heteroatom addition tank or the closed reactor, so that the oxygen content of the reaction space is 0% to 22%; the inert protective gas includes argon, nitrogen or helium; the introduction ratio of the inert protective gas is 0% to 100%; other reaction vessels have no restrictions on whether there is a protective atmosphere, that is, heat treatment can also be carried out in the air;

[0055] Further optimizing the scheme, the raw material is one or a mixture of melamine, urea, thiourea, dicyandiamide, cyanuric acid, carbon trinitrogen tetrachloride; or a mixture of one or more of other molecules that can provide carbon source and nitrogen source at the same time in any ratio;

[0056] The metallocene catalyst is one or a mixture of ferrocene, nickelocene or cobaltocene; the mass ratio of the raw material to the metallocene catalyst is 100:1-100.

[0057] Further optimization scheme, the mass volume ratio of the mixture in step 1 to the internal effective volume of the closed reactor is 1g / L to 100g / L, and the accumulation thickness of the mixture in the closed reactor is 0.01g / cm 2 ~1g / cm 2 .

[0058] To further optimize the scheme, in step 1, sodium sulfate solution or calcium silicate ethanol solution is added to the heteroatom addition tank according to the properties of the product.

[0059] The present invention also provides a production device for heteroatom-doped magnetic carbon materials, comprising: a closed reaction kettle and a heteroatom addition tank;

[0060] The closed reactor comprises a reactor body 1 and an equipment box 4; the reactor body 1 is installed in the equipment box 4, and the top of the reactor body 1 extends out of the equipment box 4, an insulation system 3 is installed on the outer wall of the reactor body 1, and the insulation system 3 is located outside the equipment box 4, and the top of the reactor body 1 is detachably connected to a reactor cover 10 through a closed connection device;

[0061] The heat preservation system 3 is used to reduce the heat exchange between the reaction system and the environment during the reaction process, and reduce the heat loss in the reaction system;

[0062] The reactor body 1 is equipped with a stirring device, the heteroatom addition tank is equipped with a stirring assembly, and the equipment box 4 is equipped with a temperature control system 5; the heteroatom addition tank is connected to the inner cavity of the reactor body 1 through a pipeline;

[0063] The temperature control system 5 is used to realize the reaction program control and temperature display and detection functions of the reactor body 1 .

[0064] Further optimization scheme, the reactor cover 10 is equipped with a safety air pressure protection device 6 and an inlet and exhaust pipe valve system 7, and the safety air pressure protection device 6 and the inlet and exhaust pipe valve system 7 are both connected to the inner cavity of the reactor body 1; the pipeline is fixedly connected and connected to the inlet and exhaust pipe valve system 7;

[0065] The closed connection device adopts any one or more of threads, ground joints, graphite sealing strips or flanges.

[0066] Further optimizing the scheme, the heteroatom addition tank comprises a heteroatom addition tank body 14, the top of the heteroatom addition tank body 14 is detachably connected with a heteroatom addition tank cover 12 through a heteroatom addition tank flange 13, a heteroatom addition tank pressure display gauge 15, a heteroatom addition tank air inlet valve 11 and a heteroatom addition tank air outlet valve 16 are installed on the heteroatom addition tank cover 12, the heteroatom addition tank pressure display gauge 15, the heteroatom addition tank air inlet valve 11 and the heteroatom addition tank air outlet valve 16 are all communicated with the inner cavity of the heteroatom addition tank body 14, and the heteroatom addition tank air outlet valve 16 is fixedly connected and communicated with a pipeline;

[0067] A liquid solvent system or a gas system that evenly disperses the target doping atoms can be added to the heteroatom addition tank body 14, and the gas can carry the target doping atoms into the reaction space of the reactor body 1 after passing through the heteroatom addition tank body 14;

[0068] The stirring assembly includes a heteroatom addition tank base 19 installed at the bottom of the heteroatom addition tank body 14, a driving motor is installed on the top of the heteroatom addition tank base 19, the driving motor is installed at the bottom of the heteroatom addition tank body 14, the output shaft of the driving motor is installed with a heteroatom addition tank stirring arm 18, the heteroatom addition tank stirring arm 18 extends into the heteroatom addition tank body 14, and the heteroatom addition tank internal stirring head 17 is installed on the heteroatom addition tank stirring arm 18.

[0069] Further optimization scheme, the reactor body 1 has a cylindrical structure, and the heat preservation system 3 includes a heat preservation and heat insulation material installed on the top of the outer wall of the reactor body 1; the heat preservation and heat insulation material includes but is not limited to heat preservation and heat insulation cotton;

[0070] The closed connection device includes two sealing flange bodies 2, which are fixedly mounted on the reactor body 1 and the reactor cover 10 respectively. The two sealing flange bodies 2 are detachably connected by a plurality of flange bolts 8, and flange nuts 9 are threadedly connected to the flange bolts 8.

[0071] As a further optimization scheme, the safety air pressure protection device 6 includes but is not limited to the use of an automatic exhaust valve with a rated maximum air pressure, which can be used in conjunction with a real-time pressure detection instrument to detect and control the air pressure in the reactor body 1.

[0072] Example 1

[0073] Take 75g of melamine as raw material and 25g of ferrocene as catalyst, mix them evenly, and put them into the reactor body 1 with an internal effective volume of 10L in air atmosphere (oxygen content 22%), and the accumulation thickness is 0.2g / cm 2 , heat treatment was carried out under the following conditions: rise to 800°C for 3h, keep constant temperature for 2h, decrease to 500°C at 10°C / min, and after naturally cooling to room temperature, take out the product, which is heteroatom-doped magnetic graphene.

[0074] Figure 5 is a scanning electron microscope photo of the product of Example 1, from Figure 5 It can be seen that the graphene sheets prepared with melamine as raw material are uniformly loaded with many nanoparticles, and the particle size distribution is about 10 to 30 nm.

[0075] Figure 6 The X-ray diffraction pattern of the product of implementation 1 is compared with the standard material card and it can be seen that the characteristic peaks in the XRD pattern correspond to C 0.08 Fe 1.92 , indicating that the magnetic nanoparticles in the sample are C 0.08 Fe 1.92 (pdf card number 44-1291);

[0076] Figure 7 This is a high-resolution transmission electron microscopy photograph of the product of Example 1, which shows that the black particles in the transmission electron microscopy photograph are actually nanoparticles with a carbon coating layer on the surface, and the coating layer has about 6 to 7 graphene layers; the presence of the coating carbon layer is beneficial to the stability of the magnetic properties of the material, otherwise it is easy to react with water and oxygen in the surrounding environment.

[0077] Figure 8 The magnetic properties of the product of Example 1. The larger hysteresis loop indicates that the material has stronger magnetic properties and can still maintain high magnetism after the magnetic field is removed.

[0078] Example 2

[0079] Take 5g urea as raw material and 0.05g ferrocene as catalyst, mix them evenly, put them into a threaded sealable graphite can with an internal effective volume of 1000mL in a high-purity nitrogen atmosphere (oxygen content 0%), and place it in the reactor body 1. The stacking thickness is 0.05g / cm 2 , heat treatment was carried out under the following conditions: rise to 1000°C for 10h, keep constant temperature for 10min, decrease to 500°C at 5°C / min, and after naturally cooling to room temperature, take out the product, which is heteroatom-doped magnetic graphene.

[0080] Example 3

[0081] Take 0.5g of dicyandiamide as raw material and 0.5g of nickelocene as catalyst, mix them evenly, and put them into the reactor body 1 with an internal effective volume of 100mL in a nitrogen and oxygen mixed atmosphere (oxygen content 30%), and the stacking thickness is 0.01g / cm 2 , sealed and placed in a muffle furnace, raised to 910°C for 2h, kept constant for 10h, decreased to 500°C at 10°C / min, and naturally cooled to room temperature before taking out the product, which is heteroatom-doped magnetic graphene.

[0082] Example 4

[0083] Take 90g of cyanuric acid as raw material and 10g of cobaltocene as catalyst, mix them evenly, put them into a sealable quartz tank with an internal effective volume of 10L in a high-purity argon atmosphere (oxygen content 0%), and place it in the reactor body 1. The stacking thickness is 1g / cm 2 , rise to 650°C for 1h, keep constant temperature for 2h, decrease to 500°C at 1°C / min, and naturally cool to room temperature before taking out the product, which is heteroatom-doped magnetic graphene.

[0084] Example 5

[0085] Take 1.5g thiourea as raw material and 0.5g ferrocene as catalyst, mix well, and put into a sealable quartz jar with an internal effective volume of 10mL. The stacking thickness is 0.2g / cm 2 , placed in the reactor body 1, add 5% by mass sodium sulfate solution in the heteroatom addition tank, uniformly introduce argon gas (0% in air atmosphere) into the reaction system, raise the temperature to 650°C for 4 hours, keep the temperature constant for 5 hours, cool naturally to room temperature, and take out the product, which is heteroatom-doped magnetic graphene.

[0086] Example 6

[0087] Take 1.5g melamine as raw material and 1.5g ferrocene as catalyst, mix them evenly, put them into a sealable ceramic jar with an internal effective volume of 100mL in an air atmosphere (oxygen content 22%), and the stacking thickness is 0.1g / cm 2 , placed in the reactor body 1, add 3% calcium silicate ethanol solution by mass into the heteroatom addition tank, raise the temperature to 850°C for 6 hours, keep the temperature constant for 4 hours, cool naturally to room temperature, and take out the product, which is heteroatom-doped magnetic graphene.

[0088] Example 7

[0089] Take 1.5g of carbon trinitrogen tetrachloride as raw material and 1.5g of ferrocene as catalyst, mix well, put into a sealable graphite can with an internal effective volume of 100mL in argon atmosphere (oxygen content 0%), and the stacking thickness is 0.2g / cm 2 , placed in the reactor body 1, add 3% calcium silicate ethanol solution by mass into the heteroatom addition tank, raise the temperature to 650°C for 6 hours, keep the temperature constant for 4 hours, cool naturally to room temperature, and take out the product, which is heteroatom-doped magnetic graphene.

[0090] Example 8

[0091] Raw materials: 70 g of urea was selected as the carbon source and nitrogen source.

[0092] Catalyst: 20 g of cobaltocene was used as the metallocene catalyst.

[0093] Atmosphere control: High-purity helium is used as the inert protective gas to ensure that the oxygen content in the reactor is 0%.

[0094] Preparation process:

[0095] The urea and the cobaltocene are uniformly mixed to form a mixture.

[0096] The mixture was loaded into a reactor with an effective internal volume of 5 L, ensuring that the stacking thickness was 0.5 g / cm 2 .

[0097] High-purity helium gas was introduced into the reactor through the connected heteroatom addition tank until the oxygen content dropped to 0%.

[0098] The reactor was heat treated by heating to 750 °C in 4 h, maintaining the temperature for 3 h, then decreasing to 500 °C at a rate of 5 °C / min, and finally naturally decreasing to room temperature.

[0099] The product is heteroatom-doped magnetic graphene.

[0100] Example 9

[0101] Raw materials: A mixture of 50 g melamine and 20 g thiourea was selected to provide both a carbon source and a nitrogen source.

[0102] Catalyst: A mixture of 10 g of ferrocene and 5 g of nickelocene was used as the catalyst.

[0103] Atmosphere control: A mixed gas of nitrogen and argon (70% nitrogen and 30% argon) was used to ensure that the oxygen content in the reactor was 5%.

[0104] Preparation process:

[0105] Mix the raw materials and catalyst evenly.

[0106] The mixture was loaded into a reactor with an effective internal volume of 2 L and a deposition thickness of 0.3 g / cm 2 .

[0107] A mixed gas of nitrogen and argon was introduced through the air inlet system of the reactor and adjusted to an oxygen content of 5%.

[0108] Heat treatment: raise the temperature to 900°C in 6 h, keep the temperature constant for 1 h, then decrease to 500°C at a rate of 8°C / min, and finally cool naturally to room temperature.

[0109] The product is taken out to obtain heteroatom-doped magnetic graphene.

[0110] Example 10

[0111] Raw materials: 80g of dicyandiamide was used as the only raw material.

[0112] Catalyst: 10 g of cobaltocene was used as the catalyst.

[0113] Atmosphere control: Use high-purity nitrogen to ensure that the oxygen content in the reactor is 0%.

[0114] Preparation process:

[0115] Mix dicyandiamide and cobaltocene evenly.

[0116] The mixture was loaded into a reactor with an effective internal volume of 8 L, and the stacking thickness was 0.8 g / cm 2 .

[0117] High-purity nitrogen was introduced into the reactor to adjust the oxygen content to 0%.

[0118] Heat treatment: increase to 850°C in 2 h, keep constant temperature for 4 h, then decrease to 500°C at a rate of 2°C / min, and finally cool naturally to room temperature.

[0119] The product is heteroatom-doped magnetic graphene.

[0120] Embodiment 11

[0121] Raw materials: Select a mixture of 60g cyanuric acid and 10g urea.

[0122] Catalyst: 30 g of ferrocene was used as a catalyst.

[0123] Atmosphere control: A mixed gas of nitrogen and a small amount of oxygen (nitrogen accounts for 90%, oxygen accounts for 10%) is used to ensure that the oxygen content in the reactor is 10%.

[0124] Preparation process:

[0125] Mix the raw materials and catalyst evenly.

[0126] The mixture was loaded into a reactor with an effective internal volume of 3 L and a deposition thickness of 0.4 g / cm 2 .

[0127] A mixed gas of nitrogen and oxygen was introduced into the reactor through the connected heteroatom addition tank and adjusted to an oxygen content of 10%.

[0128] Heat treatment: increase the temperature to 700°C in 5 h, keep the temperature constant for 5 h, then decrease to 500°C at a rate of 6°C / min, and finally cool naturally to room temperature.

[0129] The product is taken out to obtain heteroatom-doped magnetic graphene.

[0130] Example 12

[0131] Raw materials: 40g of carbon trinitrogen tetrakis used as raw material.

[0132] Catalyst: Equal amounts of nickelocene (20 g) and cobaltocene (20 g) were used as a mixed catalyst.

[0133] Atmosphere control: Use high-purity argon as the inert protective gas to ensure that the oxygen content in the reactor is 0%.

[0134] Preparation process:

[0135] The carbon trinitrogen tetrakis mixed with the mixed catalyst (nickelocene and cobaltocene) is mixed evenly.

[0136] The mixture was loaded into a reactor with an effective internal volume of 1 L, and the stacking thickness was 0.6 g / cm 2 .

[0137] High-purity argon gas was introduced into the reactor through the connected heteroatom addition tank and adjusted to an oxygen content of 0%.

[0138] Heat treatment: raise the temperature to 1000°C in 8 hours, keep the temperature constant for 0.5 hours, then reduce the temperature to 500°C at a rate of 10°C / min, and finally cool naturally to room temperature.

[0139] The product is heteroatom-doped magnetic graphene.

[0140] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0141] Obviously, the above embodiments of the present invention are merely examples for clearly explaining the present invention, and are not intended to limit the implementation methods of the present invention. For ordinary technical users in the relevant field, other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to list all the implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for preparing a heteroatom-doped magnetic carbon material, characterized in that: The following steps are involved: Step 1: uniformly mix the raw material and the metallocene catalyst to obtain a mixture, and uniformly disperse the mixture in a closed reactor; the raw material is used to provide a carbon source and a nitrogen source at the same time; Step 2: After the closed reactor is completely sealed, it is connected to the heteroatom addition tank through a pipeline, and an inert protective gas is introduced into the closed reactor to make the oxygen content in the closed reactor 0% to 22%; Step 3: Use a closed reactor to heat treat the uniform mixture, and after it naturally cools to room temperature, take out the product, which is the magnetic carbon material doped with heteroatoms.

2. The method for preparing a heteroatom-doped magnetic carbon material according to claim 1, characterized in that: The specific heat treatment conditions in step three are to increase the temperature to 650°C to 1000°C in 1h to 10h, keep the temperature constant for 10min to 10h, and cool the temperature down to 500°C at 1°C / min to 10°C / min.

3. The method for preparing a heteroatom-doped magnetic carbon material according to claim 1, characterized in that: The specific operation of step 2 is to introduce an inert protective gas into the reaction space through the air intake system of the connected heteroatom addition tank or closed reactor, so that the oxygen content of the reaction space is 0% to 22%; the inert protective gas includes argon, nitrogen or helium.

4. The method for preparing a heteroatom-doped magnetic carbon material according to claim 1, characterized in that: The raw material is one or a mixture of melamine, urea, thiourea, dicyandiamide, cyanuric acid, and C3N4; The metallocene catalyst is one or a mixture of ferrocene, nickelocene or cobaltocene; the mass ratio of the raw material to the metallocene catalyst is 100:1-100.

5. The method for preparing a heteroatom-doped magnetic carbon material according to claim 1, characterized in that: The mass volume ratio of the mixture in step 1 to the internal effective volume of the closed reactor is 1 g / L to 100 g / L, and the accumulation thickness of the mixture in the closed reactor is 0.01 g / cm 2 ~1g / cm 2 .

6. The method for preparing a heteroatom-doped magnetic carbon material according to claim 1, characterized in that: In the step 1, a sodium sulfate solution or a calcium silicate ethanol solution is added to the heteroatom addition tank.

7. A heteroatom-doped magnetic carbon material production device, based on the preparation method of the heteroatom-doped magnetic carbon material according to any one of claims 1 to 6, characterized in that: Including: closed reactor and heteroatom addition tank; The closed reactor comprises a reactor body (1) and an equipment box (4); the reactor body (1) is installed in the equipment box (4), and the top of the reactor body (1) extends out of the equipment box (4); a heat preservation system (3) is installed on the outer wall of the reactor body (1), and the heat preservation system (3) is located outside the equipment box (4); the top of the reactor body (1) is detachably connected to a reactor cover (10) via a closed connection device; The reactor body (1) is provided with a stirring device, the heteroatom addition tank is provided with a stirring assembly, and the equipment box (4) is provided with a temperature control system (5); the heteroatom addition tank is connected to the inner cavity of the reactor body (1) through a pipeline.

8. The method for preparing a heteroatom-doped magnetic carbon material according to claim 7, characterized in that: The reactor cover (10) is provided with a safety air pressure protection device (6) and an inlet and exhaust pipe valve system (7), and the safety air pressure protection device (6) and the inlet and exhaust pipe valve system (7) are both connected to the inner cavity of the reactor body (1); the pipeline is fixedly connected to and connected to the inlet and exhaust pipe valve system (7); The airtight connection device adopts any one or more of threads, ground joints, graphite sealing strips or flanges.

9. The method for preparing a heteroatom-doped magnetic carbon material according to claim 7, characterized in that: The heteroatom addition tank comprises a heteroatom addition tank body (14); the top of the heteroatom addition tank body (14) is detachably connected to a heteroatom addition tank cover (12) via a heteroatom addition tank flange (13); a heteroatom addition tank pressure display gauge (15), a heteroatom addition tank air inlet valve (11) and a heteroatom addition tank air outlet valve (16) are installed on the heteroatom addition tank cover (12); the heteroatom addition tank pressure display gauge (15), the heteroatom addition tank air inlet valve (11) and the heteroatom addition tank air outlet valve (16) are all in communication with the inner cavity of the heteroatom addition tank body (14); and the heteroatom addition tank air outlet valve (16) is fixedly connected to and in communication with the pipeline; The stirring assembly comprises a heteroatom addition tank base (19) mounted at the bottom of the heteroatom addition tank body (14); a driving motor is mounted on the top of the heteroatom addition tank base (19); the driving motor is mounted at the bottom of the heteroatom addition tank body (14); a heteroatom addition tank stirring arm (18) is mounted on the output shaft of the driving motor; the heteroatom addition tank stirring arm (18) extends into the heteroatom addition tank body (14); and a heteroatom addition tank internal stirring head (17) is mounted on the heteroatom addition tank stirring arm (18).

10. The method for preparing a heteroatom-doped magnetic carbon material according to claim 8, characterized in that: The reactor body (1) has a cylindrical structure, and the heat preservation system (3) comprises a heat preservation and heat insulation material installed on the top of the outer wall of the reactor body (1); The sealed connection device comprises two sealing flange bodies (2), the two sealing flange bodies (2) are fixedly mounted on the reactor body (1) and the reactor cover (10) respectively, the two sealing flange bodies (2) are detachably connected via a plurality of flange bolts (8), and flange nuts (9) are threadedly connected to the flange bolts (8).

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