Double-anode electric arc furnace for preparing carbon nanomaterial

Abstract

The utility model discloses a double-anode electric arc furnace device for preparing carbon nanomaterials, which belongs to the field of nanomaterial preparation equipment, and comprises a furnace body, a base, cathode assemblies and anode assemblies, the furnace body comprises a working cavity and a transition cavity, the double-anode electric arc furnace is provided with a group of cathode assemblies and at least two groups of anode assemblies, and a cathode bar rotating rod and an anode bar outer sleeve are arranged outside the working cavity. The electric arc furnace comprises a metal main body, vacuum maintenance and gas inlet and outlet, a plurality of anodes, a cathode, a motion control structure of the anodes and the cathode, an electric control button and the like. Various metal components are respectively added into two (or more) anodes, and the magnitude of arc discharge current is respectively adjusted, so that each component can be evaporated at a proper rate, the concentration proportion of each component at an arc core is relatively proper, and the components interact with one another to form a catalyst with proper size and component, and the catalyst is used for catalyzing the growth of a carbon nanomaterial. The device is simple in structure, remarkable in effect and high in controllability, and universal preparation of the carbon nanomaterial based on the multi-metal-component catalyst can be realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of electric arc furnaces, and in particular relates to a double anode electric arc furnace for preparing carbon nanomaterials. Background Art

[0002] The arc method is the earliest process used to prepare carbon nanomaterials, and is also one of the current methods for mass production of carbon nanomaterials. Using a graphite rod or a composite rod containing metal and graphite as an anode and a graphite rod (disk) as a cathode, in a vacuum reaction chamber filled with inert gas or hydrogen, the cathode and the anode are short-circuited, and the distance between the electrodes is adjusted to generate a discharge arc, and the carbon nanomaterial is obtained by consuming the pure graphite rod or the graphite-metal composite anode.

[0003] It is generally believed that the ultra-high temperature at the arc core sublimates graphite into carbon vapor, and at the same time, when electrons are ejected from the cathode to the anode, carbon precursors are also sputtered, causing carbon to be evaporated out of the anode in the form of atoms or atomic clusters. Under the regulation of temperature gradient and particle concentration gradient, carbon vapor drifts in the gas phase to the cathode and furnace wall with lower temperatures, gradually cools, condenses, nucleates, and grows into various carbon nanoproducts. Depending on the arc conditions such as current and atmosphere and the type and content of the metal components in the anode, the obtained carbon nanoproducts can be fullerenes, carbon nanotubes, graphene, carbon onions, etc.

[0004] The existing electric arc furnaces used to prepare carbon nanomaterials usually have a cathode and an anode. Even if the preparation of the carbon nanomaterials requires a variety of different metal components, they can only be placed in the same anode rod. However, when the same anode contains more than two metal components, the different metal components have different physical and chemical properties such as melting and boiling points and saturated vapor pressure, and the required appropriate discharge current is also different. When the discharge current is adjusted to be suitable for one of the metal components, it may not be suitable for other metal components. The current may be too small and completely unable to evaporate, or the current may be too large and the evaporation rate may be too fast, so that large metal particles are directly splashed out. At this time, it is difficult to have multiple metal components with suitable particle concentrations at the arc core at the same time.

[0005] Therefore, it is necessary to develop an electric arc furnace device that can separate multiple metal components during the evaporation stage, evaporate them separately with different currents, and gather them at the arc core when catalyzing the growth of carbon nanomaterials, so as to achieve the universal preparation of carbon nanomaterials based on multi-metal component catalysts. Utility Model Content

[0006] In order to solve the above problems, the utility model provides a double anode electric arc furnace, which is designed with cathode components and anode components. The cathode rod and anode rod are pushed to the predetermined position of the working chamber of the electric arc furnace by the rotating rod and the screw-in cylinder in the components to work. Several anode components can be set to realize current regulation to meet the requirements of different raw materials. The operation of the electric arc furnace is controlled by the control circuit, which is easy to operate and accurate in control, and is convenient for the preparation of materials such as carbon nanotubes.

[0007] The utility model provides a double-anode electric arc furnace for preparing carbon nanomaterials, which comprises a furnace body, a base, a cathode assembly and an anode assembly.

[0008] The furnace body comprises a working chamber and a transition chamber.

[0009] The dual anode electric arc furnace has one set of cathode assemblies and at least two sets of anode assemblies.

[0010] The cathode assembly comprises a cathode rod rotating rod, a cathode rod screwing column and a cathode rod.

[0011] The anode assembly comprises an anode rod outer sleeve, an anode rod screw-in sleeve and an anode rod.

[0012] A cathode rod rotating rod and an anode rod outer sleeve are arranged outside the working chamber.

[0013] The cathode rod is screwed into the column to push the cathode rod to the predetermined position in the working chamber relative to the cathode rod.

[0014] An anode rod screw-in cylinder is arranged inside the anode rod outer sleeve, and the anode rod screw-in cylinder can rotate relative to the anode rod outer sleeve to push the anode rod to a predetermined position in the working chamber of the electric arc furnace.

[0015] The utility model has the following beneficial effects:

[0016] (1) The utility model overcomes the problem that multiple metal catalyst components in a traditional single anode electric arc furnace are difficult to synergistically catalyze the growth of carbon nanomaterials at an appropriate concentration ratio at the arc core due to differences in physical and chemical properties.

[0017] (2) The utility model is the first to use multiple anodes facing the same cathode in an electric arc furnace structure to discharge with currents of different magnitudes simultaneously, so as to achieve separate regulation of the concentrations of various metal components at the arc core. It has broad application prospects in the field of arc preparation of carbon nanomaterials, and is particularly suitable for the preparation of systems that require multiple metal catalysis and have large differences in the melting and boiling points of the metals.

[0018] (3) The cathode assembly and the anode assembly of the utility model are designed to have the function of manually and automatically screwing the cathode rod into a specified position, which is convenient for operation and also convenient for accurately controlling the positions of the cathode and the anode.

[0019] (4) The utility model provides an arc furnace that can realize the control of vacuum extraction, atmosphere gas intake, cooling water and other conditions through a control circuit, and can realize the accurate positioning of the cathode rod and the anode rod, thereby ensuring the repeatability of the experimental conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the external structure of a double anode electric arc furnace of the utility model is shown;

[0021] Figure 2 A schematic diagram of the structure of a cathode assembly of the utility model is shown;

[0022] Figure 3 A structural schematic diagram of an anode assembly 4 of the utility model is shown.

[0023] Description of Figure Numbers

[0024] 1-furnace body;

[0025] 101-working chamber;

[0026] 1011-top cover;

[0027] 1012- material receiving port;

[0028] 1013- Main observation window;

[0029] 1014-side observation window;

[0030] 1015-Vacuum pump;

[0031] 1016-knob type air intake;

[0032] 102-transition cavity;

[0033] 1021-Vacuum gauge;

[0034] 1022-Vacuum gauge;

[0035] 2- base;

[0036] 3- cathode assembly;

[0037] 301- cathode rod rotating rod;

[0038] 3011-bearing;

[0039] 302- cathode rod screws into the column;

[0040] 303- cathode rod;

[0041] 3031-sealing ring;

[0042] 3032-fixing ring;

[0043] 4- anode assembly;

[0044] 401- anode rod outer sleeve;

[0045] 402- anode rod screws into the cylinder;

[0046] 403- anode rod;

[0047] 404 - Stepper motor. DETAILED DESCRIPTION

[0048] The present invention will be described in detail below through specific implementation modes, and the features and advantages of the present invention will become clearer and more explicit with these descriptions.

[0049] The utility model provides a double-anode electric arc furnace for preparing carbon nanomaterials, which comprises a furnace body 1, a base 2, a cathode assembly 3, and an anode assembly 4.

[0050] The furnace body 1 includes a working chamber 101 and a transition chamber 102, wherein the transverse cross section of the working chamber 101 is larger than the transverse cross section of the transition chamber 102. Figure 1 .

[0051] The working chamber 101 is arranged on the base 2, and a top cover 1011 is arranged on the top. A sealing ring is arranged at the contact part between the top cover 1011 and the cavity of the working chamber 101 to seal the top cover 1011 and the cavity. The top cover 1011 is opened to facilitate cleaning of the working chamber 101.

[0052] The transition chamber 102 is arranged on the top cover 1011, and the working chamber 101 and the transition chamber 102 are connected. A vacuum meter 1021 and a vacuum gauge 1022 are arranged on the top of the transition chamber 102 to accurately measure the vacuum degree inside the working chamber 101. The transition chamber 102 is arranged between the working chamber 101 and the vacuum meter 1021 and the vacuum gauge 1022 to prevent the sample from entering the vacuum meter 1021 and the vacuum gauge 1022. The measurement range of the vacuum meter 1021 is -1 to +1.5 atm, and the measurement range of the vacuum gauge 1022 is 0.1 to 993000 Pa, which can accurately measure the pressure below 1000 Pa.

[0053] The dual anode electric arc furnace has a cathode assembly 3. The cathode assembly 3 includes a cathode rod rotating rod 301, a cathode rod rotating column 302, and a cathode rod 303. Figure 2 shown.

[0054] The cathode rod screw-in column 302 can rotate relative to the cathode rod rotating rod 301 to push the cathode rod 303 to a predetermined position in the working chamber 101 .

[0055] The working chamber 101 is provided with a fixed bearing 3011 on the outer side of the working chamber 101, and the cathode rod rotating rod 301 is fixed at the tail end of the bearing 3011, so that the cathode rod rotating rod 301 can rotate relative to the bearing. A handle is provided at the outer end of the cathode rod rotating rod 301 for easy operation. The surfaces of the cathode rod rotating rod 301 and the cathode rod screw-in column 302 are both provided with spiral gear teeth, and the two are meshed through the gear teeth. The cathode rod screw-in column 302 can be screwed in and out relative to the cathode rod rotating rod 301. The cathode rod screw-in column 302 is pushed forward or backward by rotating the cathode rod rotating rod 301, so as to accurately adjust the length of the cathode rod 303 extending out of the working chamber 101.

[0056] The cathode rod is screwed into the column 302 to fix the tail of the cathode rod 303 , and the cathode rod is screwed into the column 302 and can be electrically connected to the cathode rod 303 .

[0057] One end of the cathode rod 303 is fixed inside the cathode rod screw-in column 302 and extends horizontally to the inside of the working chamber 101. The outer side of the working chamber 101 is disconnected from the cathode rod 303. A sealing ring 3031 is sleeved on the outside of the cathode rod 303 and is pressed and fixed by a fixing ring 3032 to keep the cathode rod 303 and the working chamber 101 sealed.

[0058] The cathode rod 303 is connected to a plurality of conductors, each of which is connected to the negative electrode of a DC arc welding machine.

[0059] The double anode electric arc furnace has at least two groups of anode assemblies 4. The anode assembly 4 includes an anode rod outer sleeve 401, an anode rod screw-in sleeve 402, and an anode rod 403.

[0060] A cathode rod rotating rod 301 and an anode rod outer sleeve 401 are arranged outside the working chamber 101. Preferably, two or more anode rod outer sleeves 401 are arranged and fixed on the side of the working chamber 101 opposite to the side where the cathode rod rotating rod 301 is arranged, such as two upper and lower anode rod outer sleeves 401, and threads are arranged on the inner wall of the anode rod outer sleeve 401. An anode rod screw-in cylinder 402 is arranged inside the anode rod outer sleeve 401, and the anode rod screw-in cylinder 402 can rotate relative to the anode rod outer sleeve 401 to push the anode rod 403 to a predetermined position in the working chamber 101 of the electric arc furnace. The tail of the anode rod 403 is fixed inside the anode rod screw-in cylinder 402, and threads are arranged on the outer surface, so that the anode rod screw-in cylinder 402 can be screwed in and out inside the anode rod outer sleeve 401 to adjust the length of the anode rod 403 extending out. Specifically, Figure 3 shown.

[0061] Each anode rod 403 is connected to a conductor, which is connected to the positive pole of a DC arc welding machine.

[0062] The anode rod screw-in cylinder 402 is connected to a stepping motor 404 , and the anode rod screw-in cylinder 402 can be rotated when the motor is turned on.

[0063] The inclination angle of the anode rod outer sleeve 401 enables the extended anode rod 403 to be docked with the extended cathode rod 303 .

[0064] The working chamber 101 is provided with an interlayer for introducing cooling water, which is connected to a water chiller through a water distributor to control the temperature of the cooling water.

[0065] A receiving port 1012 is provided at the bottom of the working chamber 101 for discharging powder products, such as carbon nanotubes, produced in the working chamber 101 .

[0066] The working chamber 101 is provided with a vacuum valve to control the opening or closing of vacuuming. The vacuum valve is connected to the vacuum pump 1015.

[0067] The working chamber 101 is provided with a knob-type air inlet 1016 for introducing gas, and the air inlet is connected to a gas flow meter for measuring the air inlet flow.

[0068] The side of the working chamber 101 is also provided with a main observation window 1013 and a side observation window 1014 for observing the situation in the chamber. The main observation window 1013 and the side observation window 1014 are made of quartz glass or organic glass. The main observation window 1013 and the side observation window 1014 are provided with slots outside for inserting a shading plate.

[0069] The double anode electric arc furnace is controlled by a control circuit.

[0070] The utility model places multiple metal components on two (or more) anodes respectively, and uses the cathode assembly 3 and the anode assembly 4 to accurately control the accurate positioning of the cathode rod 301 and the anode rod 401. The design is reasonable, and the operation is accurate and simple. The arc discharge current is adjusted separately, so that each component can be evaporated at a suitable rate, so that the concentration gradient at the arc core is suitable, and the catalyst with suitable size and components is formed by interaction to catalyze the growth of carbon nanotubes.

[0071] The present invention is described in detail above in conjunction with the specific implementation methods and the accompanying drawings, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, the technical solution of the present invention and its implementation methods may be subjected to a variety of equivalent substitutions, modifications or improvements, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

Claims

1. A double anode electric arc furnace for preparing carbon nanomaterials, characterized in that: It comprises a furnace body (1), a base (2), a cathode assembly (3) and an anode assembly (4). The furnace body (1) comprises a working chamber (101) and a transition chamber (102). The double anode electric arc furnace has a set of cathode assemblies (3) and at least two sets of anode assemblies (4). The cathode assembly (3) comprises a cathode rod rotating rod (301), a cathode rod screwing column (302) and a cathode rod (303). The anode assembly (4) comprises an anode rod outer sleeve (401), an anode rod screw-in sleeve (402) and an anode rod (403). A cathode rod rotating rod (301) and an anode rod outer sleeve (401) are arranged outside the working chamber (101). The cathode rod screw-in column (302) can rotate relative to the cathode rod screw rod (301) to push the cathode rod (303) to a predetermined position in the working chamber (101). An anode rod screw-in cylinder (402) is arranged inside the anode rod outer sleeve (401). The anode rod screw-in cylinder (402) can rotate relative to the anode rod outer sleeve (401) to push the anode rod (403) to a predetermined position in the arc furnace working chamber (101).

2. The double anode electric arc furnace according to claim 1, characterized in that: The transverse cross-section of the working chamber (101) is larger than the transverse cross-section of the transition chamber (102).

3. The double anode electric arc furnace according to claim 1, characterized in that: The working chamber (101) is arranged on the base (2), a top cover (1011) is arranged on the top, and a sealing ring is arranged at the contact portion between the top cover (1011) and the cavity body of the working chamber (101).

4. The double anode electric arc furnace according to claim 3, characterized in that: The transition chamber (102) is arranged on the top cover (1011), and the working chamber (101) and the transition chamber (102) are connected.

5. The double anode electric arc furnace according to claim 1, characterized in that: A vacuum meter (1021) and a vacuum gauge (1022) are arranged on the top of the transition chamber (102).

6. The double anode electric arc furnace according to claim 1, characterized in that: A horizontal cathode rod rotating rod (301) is arranged outside the side of the working chamber (101). The cathode rod rotating rod (301) and the cathode rod screwing-in column (302) are both provided with spiral gear teeth on their surfaces, and the two are meshed through the gear teeth, so that the cathode rod screwing-in column (302) can be screwed in and out relative to the cathode rod rotating rod (301).

7. The double anode electric arc furnace according to claim 1, characterized in that: The cathode rod is screwed into the column (302) to fix the tail of the cathode rod (303), and the cathode rod is screwed into the column (302) and can be connected to the cathode rod (303). The cathode rod is screwed into the column (302) to connect a plurality of wires, each of which is connected to the negative electrode of a DC arc welding machine.

8. The double anode electric arc furnace according to claim 1, characterized in that: Two or more anode rod outer sleeves (401) are fixedly arranged on the side of the working chamber (101) opposite to the side where the cathode rod rotating rod (301) is arranged. The inner wall of the anode rod outer sleeve (401) is provided with threads.

9. The double anode electric arc furnace according to claim 1, characterized in that: The anode rod screw-in cylinder (402) is used to fix the tail of the anode rod (403) and has a threaded surface on the outside so that the anode rod screw-in cylinder (402) can be screwed in and out of the anode rod outer sleeve (401). Each anode rod is screwed into the cylinder (402) and connected to a conductor, which is connected to the positive electrode of a DC arc welding machine.

10. The double anode electric arc furnace according to claim 1, characterized in that: The working chamber (101) is provided with an interlayer for passing cooling water. A material receiving port (1012) is provided at the bottom of the working chamber (101). The working chamber (101) is provided with a vacuum valve. The working chamber (101) is provided with a knob-type air inlet (1016). A main observation window (1013) and a side observation window (1014) are also provided on the side of the working chamber (101).

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