Vertical reaction frame for preparing novel nano material through Joule thermal reaction

Abstract

The utility model belongs to the technical field of nano material preparation, and particularly relates to a vertical reaction frame for preparing novel nano materials through Joule thermal reaction. The reaction frame mainly comprises a bottom plate, a middle plate, a top plate, guide columns, springs, upper and lower insulating plates, upper and lower graphite electrodes and conductive powder filled in quartz tubes. Power is supplied through a direct-current power source, Joule heat is generated between the graphite electrodes, and the conductive powder is heated to a high-temperature state. In the heating process, the intermediate plate applies continuous pressure to the graphite electrode under the action of the spring, so that good contact between reactant powder and stable resistance are ensured, and normal Joule thermal reaction is ensured. The Joule thermal reaction device is simple in structure and convenient to operate, the efficiency and quality of Joule thermal reaction can be effectively improved, and a new scheme is provided for research and production of novel nano materials such as graphene.

Description

Technical Field

[0001] The utility model belongs to the technical field of nano material preparation, and specifically relates to a vertical reaction rack used for preparing novel nano materials by Joule heat reaction. Background Art

[0002] With the rapid development of science and technology, research in the field of materials science has gradually deepened. Among them, the Joule heat principle, as a powerful tool, has been playing an important role in the field of material preparation since it was discovered by British physicist Joule in 1841. In recent years, researchers have cleverly used the high-temperature Joule heat generated by large currents passing through conductive powders to prepare a variety of cutting-edge nanomaterials in a very short time, such as graphene, carbon fiber, nanotubes, and high-entropy alloys, which has greatly promoted the development of materials science.

[0003] However, during the Joule heat reaction, the conductive powder will undergo significant physical structural changes in a high temperature (2000 to 3000°C) environment, which may even cause volume collapse, making the powder particles that were originally in close contact become loose and the conductivity significantly reduced. This reduction in conductivity will directly affect the size of the Joule heat discharge current, resulting in a reduction in power, which in turn makes it impossible for the Joule heat reaction to continue to proceed efficiently, and the temperature cannot be further increased, which may eventually lead to the termination of the reaction.

[0004] In order to solve this problem, existing reaction rack designs, such as the Joule heat pipe reaction rack disclosed in application number CN202320359603.5, can horizontally support the reaction tube for Joule heat reaction. However, since its horizontal placement design does not take into account the loose contact problem caused by the physical structure change of the reactants at high temperature, the Joule heat discharge current and power cannot be sustainably guaranteed, resulting in a serious impact on the reaction efficiency.

[0005] Therefore, in order to ensure the efficient Joule heat reaction, reach the required reaction temperature, and successfully complete the reaction, we urgently need to redesign a Joule heat reaction rack design. This new reaction rack can continuously apply pressure to the reactant powder during the Joule heat reaction, ensuring that the reactant powder always maintains close contact, thereby maintaining good conductivity and ensuring the efficient and stable Joule heat reaction. Utility Model Content

[0006] The Joule heat pipe reaction rack in the background art does not take into account the loose contact problem caused by the physical structure change of the reactants at high temperature due to its horizontal placement design. At the same time, in order to ensure that the Joule heat reaction of the conductive reactant powder continues to proceed, reach a higher Joule heat temperature, and achieve a better reaction effect, the utility model provides a vertical reaction rack for preparing new nanomaterials by Joule heat reaction.

[0007] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a vertical reaction frame for preparing new nanomaterials by Joule heat reaction, comprising a bottom plate and a top plate, the two being connected by at least one pair of guide columns, an intermediate plate being slidably arranged on the guide columns, a spring being arranged on the guide columns between the bottom plate and the intermediate plate, a quartz tube being placed between the intermediate plate and the bottom plate, a lower graphite electrode and an upper graphite electrode being arranged at both ends of the quartz tube, and conductive powder being filled therein, a lower insulating plate being arranged between the lower graphite electrode and the bottom plate, an upper insulating plate being arranged between the upper graphite electrode and the middle plate, the lower graphite electrode and the upper graphite electrode being electrically connected to a DC power supply through a wire, the DC power supply providing the power required for Joule heat, and the intermediate plate continuously applying a certain pressure to the conductive powder on the upper graphite electrode through the upper insulating plate under the elastic action of the spring, thereby ensuring good conductivity during the entire Joule heat reaction process.

[0008] As a further supplement to the above technical solution, the lower graphite electrode has the same structure as the upper graphite electrode, both of which are divided into two parts: a square graphite block and a graphite cylinder. The square graphite block is used to connect a DC power supply through a wire, and the graphite cylinder is inserted in a quartz tube.

[0009] As a further supplement to the above technical solution, the bottom plate, middle plate and top plate are respectively made of aluminum plates, the guide column is the optical axis and is provided with external threads at both ends, the bottom plate and the top plate are fixedly connected by external threads and nuts at both ends of the optical axis, a through hole is provided in the middle plate, and the middle plate is slidably set on the optical axis using the through hole.

[0010] As a further explanation and limitation of the above technical solution, the lower insulating plate and the upper insulating plate are both high-temperature fire-resistant plates.

[0011] As a further explanation and limitation of the above technical solution, the DC power supply is voltage and current adjustable, with a maximum voltage of 100V and a maximum current of 400A.

[0012] Compared with the prior art, the utility model has the following advantages:

[0013] 1. The utility model utilizes the spring on the guide column to generate continuous and uniform pressure on the reactant powder through the middle plate, the upper insulating plate, and the graphite upper electrode; during discharge, when the current passes through the conductive reactant to generate Joule heat and the temperature rises, the reactant becomes loose, and at this time the graphite upper electrode moves downward under pressure to maintain good conductivity of the reactant, and finally the reactant generates a new type of nanomaterial under high Joule heat.

[0014] 2. The utility model can adjust the resistance of the Joule heat reactant by adjusting the pressure of the spring, further control the Joule heat heating speed and the maximum temperature, and meet different Joule heat reaction conditions.

[0015] 3. The vertical reaction rack designed by the utility model has a simple structure and is easy to operate. It can effectively improve the efficiency and quality of Joule heat reaction and provide a new solution for the research and production of new nanomaterials such as graphene. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural diagram of the Joule heat vertical reaction frame in the utility model;

[0017] In the figure: the bottom plate is 1, the middle plate is 2, the top plate is 3, the guide column is 4, the spring is 5, the lower insulating plate is 6, the lower graphite electrode is 7, the quartz tube is 8, the upper graphite electrode is 9, the upper insulating plate is 10, the conductive powder is 11, and the DC power supply is 12. DETAILED DESCRIPTION

[0018] In order to further illustrate the technical solution of the utility model, the following Figure 1 According to the manufacturing process of the Joule heat vertical reaction rack and the implementation process of the Joule heat reaction, we further illustrate the utility model through the optimal embodiment.

[0019] As attached Figure 1 As shown, a vertical reaction rack for preparing new nanomaterials by Joule heat reaction includes a bottom plate 1 and a top plate 3, which are connected by at least one pair of guide columns 4, an intermediate plate 2 is slidably arranged on the guide columns 4, a spring 5 is arranged on the guide columns 4 between the bottom plate 1 and the intermediate plate 2, a quartz tube 8 is placed between the intermediate plate 2 and the bottom plate 1, a lower graphite electrode 7 and an upper graphite electrode 9 are arranged at both ends of the quartz tube 8, the lower graphite electrode 7 and the upper graphite electrode 9 have the same structure, and both are divided into two parts, a square graphite block and a graphite cylinder, the graphite cylinder is inserted in the quartz tube 8, and the quartz The tube 8 is sealed with two graphite cylinders and filled with conductive powder 11. A lower insulating plate 6 is arranged between the lower graphite electrode 7 and the bottom plate 1, and an upper insulating plate 10 is arranged between the upper graphite electrode 9 and the middle plate 2. The upper and lower square graphite blocks are in contact with the upper insulating plate 10 and the lower insulating plate 6 respectively, and the two are used to connect a DC power supply 12 through a wire. The DC power supply 12 provides the electricity required for Joule heat. Under the elastic action of the spring 5, the middle plate 2 continuously applies a certain pressure to the conductive powder 11 through the upper insulating plate 10 on the upper graphite electrode 9 to ensure good conductivity during the entire Joule heat reaction process.

[0020] Furthermore, the bottom plate 1, the middle plate 2 and the top plate 3 are respectively made of aluminum plates, the guide column 4 is an optical axis and is provided with external threads at both ends, the bottom plate 1 and the top plate 3 are fixedly connected by external threads and nuts at both ends of the optical axis, a through hole is provided in the middle plate 2, and the middle plate 2 is slidably set on the optical axis using the through hole.

[0021] In this embodiment, the DC power supply 12 is a 40 kW DC power supply with adjustable voltage and current, a maximum voltage of 100 V, and a maximum current of 400 A.

[0022] Based on the above embodiments, we list the specific implementation methods for the implementation process of producing new graphene nanomaterials using the Joule heat method: Take three 300mm×100mm×10mm aluminum plates, two of which are made with M6 threads at a distance of 20mm from the four corners, which serve as the bottom plate and the top plate respectively; the third one is drilled with a through hole of 17mm in diameter at a distance of 20mm from the four corners, which serves as the middle plate. Take four optical axes with a diameter of 16mm and a length of 300mm, with M6 threads at both ends, as guide columns. Take four springs with a wire diameter of 1.5mm, a length of 100mm and an outer diameter of 21mm as pressure springs. Fix the bottom plate, the middle plate, the guide column, the top plate, and the spring with screws at the four corners to obtain. Figure 1 Of course, since the diameters of the four holes in the middle plate are slightly larger than the guide posts, the middle plate can freely move up and down along the guide posts under the expansion and contraction of the spring.

[0023] The insulating plates are two 100mm×100mm×10mm high temperature fireproof plates; the lower electrode is a 100mm×100mm×20mm graphite block with a graphite cylinder with a diameter of 40mm and a length of 20mm on it; the upper electrode is a 100mm×100mm×20mm graphite block with a graphite cylinder with a diameter of 40mm and a length of 60mm on it; the quartz tube is a quartz tube with an outer diameter of 50mm and an inner diameter of 40mm, and 60 grams of granulated conductive carbon black is placed in the middle. Figure 1 Assemble and install the Joule heat vertical reaction frame. At this time, the 100mm long spring is compressed to 40mm, generating a certain pressure, and the cylindrical part of the graphite upper electrode is 40mm outside the quartz tube.

[0024] Put the assembled vertical reaction rack into a vacuum box as a whole, then connect it to a DC power supply, adjust the DC power supply to a maximum voltage of 100V and a maximum current of 400A, close the vacuum box, and evacuate to -0.098MPa. At this time, adjust the maximum output voltage to 90V and the maximum output current to 350A for discharge. The current flows through the conductive carbon black through the lower graphite electrode, and finally returns to the negative pole of the DC power supply through the upper graphite electrode. Because the resistance of the conductive carbon black is relatively large, the current generates Joule heat, gradually heating the conductive carbon black. As the temperature rises to 800°C, the upper graphite electrode begins to move slowly downward, keeping the resistance below 1 ohm, and the temperature continues to rise. After the upper graphite electrode moves down 30mm, it basically stops moving downward. The temperature rises further until 3000°C. Turn off the DC power supply, the Joule heat reaction stops, and the temperature of the carbon black in the quartz tube drops rapidly from 3000°C to 1500°C, and then gradually and slowly drops to room temperature. At this time, the Joule heat reaction product was taken out and Raman spectroscopy was performed, and an obvious 2D peak of graphene appeared, indicating that the conductive carbon black had generated graphene after the Joule heat reaction.

[0025] It can be seen that when preparing new nanomaterials by Joule heat reaction, the particle or powder reactant will collapse at high temperature, resulting in poor contact between the reactant particles, thereby increasing the reactant resistance and preventing the normal Joule heat reaction. In order to keep the reactant particles in good contact during the heating process, the vertical reaction rack can continuously apply pressure during the Joule heat reaction, keep the reactant powder in good contact, and keep the resistance stable, further ensuring the normal Joule heat reaction.

[0026] It should be noted that the insulating plate in the above embodiment can also be made of quartz, alumina ceramics, magnesium oxide ceramics, boron nitride ceramics, polytetrafluoroethylene (PTFE), para-polyphenylene (PPL), polybenzimidazole (PBI), polyetheretherketone (PEEK), polyimide (PI) or polyamideimide (PAI). In addition, the graphite electrode material can also be replaced by stainless steel, tungsten, tungsten steel, and iron. For those skilled in the art, it is obvious that the specific implementation of the utility model is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the utility model, the above-mentioned equivalent replacement means, in other specific forms to realize the creative ideas and design ideas of the utility model, should be equivalent to the protection scope disclosed in the technical solution of the utility model.

[0027] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A vertical reaction rack for preparing novel nanomaterials by Joule heat reaction, comprising a bottom plate (1) and a top plate (3), characterized in that: The two are connected by at least one pair of guide columns (4), an intermediate plate (2) is slidably arranged on the guide columns (4), a spring (5) is arranged on the guide columns (4) between the bottom plate (1) and the intermediate plate (2), a quartz tube (8) is placed between the intermediate plate (2) and the bottom plate (1), a lower graphite electrode (7) and an upper graphite electrode (9) are arranged at both ends of the quartz tube (8), and conductive powder (11) is filled inside the quartz tube, and a conductive electrode (11) is arranged between the lower graphite electrode (7) and the bottom plate (1). A lower insulating plate (6) is provided, and an upper insulating plate (10) is provided between the upper graphite electrode (9) and the middle plate (2). The lower graphite electrode (7) and the upper graphite electrode (9) are electrically connected to a DC power supply (12) via a wire, and the DC power supply (12) provides the power required for Joule heat. Under the elastic action of the spring (5), the middle plate (2) continuously applies a certain pressure to the upper graphite electrode (9) through the upper insulating plate (10), thereby ensuring good conductivity during the entire Joule heat reaction process.

2. A vertical reaction rack for preparing novel nanomaterials by Joule heat reaction according to claim 1, characterized in that: The lower graphite electrode (7) and the upper graphite electrode (9) have the same structure, and both are divided into two parts: a square graphite block and a graphite cylinder. The square graphite block is used to connect a DC power supply (12) through a wire, and the graphite cylinder is inserted in a quartz tube (8).

3. A vertical reaction rack for preparing novel nanomaterials by Joule heat reaction according to claim 1 or 2, characterized in that: The bottom plate (1), the middle plate (2) and the top plate (3) are respectively made of aluminum plates; the guide column (4) is an optical axis and is provided with external threads at both ends; the bottom plate (1) and the top plate (3) are fixedly connected via external threads at both ends of the optical axis and nuts; a through hole is provided in the middle plate (2); and the middle plate (2) is slidably arranged on the optical axis using the through hole.

4. A vertical reaction rack for preparing novel nanomaterials by Joule heat reaction according to claim 3, characterized in that: The lower insulating plate (6) and the upper insulating plate (10) are both high-temperature fire-resistant plates.

5. A vertical reaction rack for preparing novel nanomaterials by Joule heat reaction according to claim 4, characterized in that: The DC power supply (12) is of a voltage and current adjustable type, with a maximum voltage of 100V and a maximum current of 400A.

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