Nitride production apparatus based on radio frequency plasma generator and production process

Abstract

The application belongs to the technical field of nitride preparation, and particularly relates to a nitride production device and production process based on a radio frequency plasma generator; wherein the device comprises: a high-temperature reaction furnace, one end of the high-temperature reaction furnace is provided with a radio frequency plasma generator, an arc plasma generator is further arranged on the high-temperature reaction furnace wall close to the radio frequency plasma generator, the flame outlets of the radio frequency plasma generator and the arc plasma generator are both located in the high-temperature reaction furnace, and the included angle between the flame directions of the radio frequency plasma generator and the arc plasma generator is an acute angle; a feeding port is arranged at the central axis of the radio frequency plasma generator; a primary collector is arranged at the other end of the high-temperature reaction furnace, and a discharging port is further arranged on the high-temperature reaction furnace wall close to the primary collector; and nitrogen is used as the working gas of the radio frequency plasma generator and the arc plasma generator. The nitride prepared by the radio frequency plasma generator has the advantages of high purity, good powder particle size consistency and high sphericity.

Description

Technical Field

[0001] This invention relates to the field of nitride preparation technology, and specifically discloses nitride production equipment and production process based on radio frequency plasma generator. Background Technology

[0002] Nitrides, such as magnesium nitride and aluminum nitride, typically possess superior physicochemical properties and are widely used in the preparation of tough ceramic materials and as ammonia storage materials in chemical chain ammonia synthesis processes. The excellent properties of these nitride materials are based on the quality of their powders. The key to preparing high-performance nitride materials lies in preparing high-purity, fine-grained, and high-performance powder raw materials.

[0003] Currently, the main synthesis methods for the industrial production of aluminum nitride powder include direct nitriding and carbothermic reduction. Direct nitriding involves heating aluminum powder directly in a nitrogen atmosphere, causing the aluminum powder to react with nitrogen to form aluminum nitride. Because aluminum powder is easily combustible at high temperatures, and the nitriding reaction is slow at low temperatures, this method requires precise temperature control, and the synthesized AlN suffers from low purity, poor controllability, and high energy consumption. Carbothermic reduction involves heating alumina and carbon powder in a nitrogen atmosphere, generating aluminum nitride through a carbothermic reduction reaction. This method has a complex process flow, produces byproducts such as carbon monoxide and carbon dioxide during the reaction, and may introduce carbon impurities, making it difficult to control the purity of the aluminum nitride.

[0004] It is evident that producing high-purity nitrides using existing technology remains quite challenging. Summary of the Invention

[0005] The purpose of this invention is to provide nitride production equipment and process based on a radio frequency plasma generator, solving the technical problem of low purity in nitride production; the specific solution is as follows:

[0006] Firstly, it provides nitride production equipment based on radio frequency plasma generators, including:

[0007] A high-temperature reactor is provided with a radio frequency plasma generator at one end and an electric arc plasma generator is also provided on the furnace wall near the radio frequency plasma generator. The flame outlets of the radio frequency plasma generator and the electric arc plasma generator are both located inside the high-temperature reactor, and the angle between the flame outlet directions of the radio frequency plasma generator and the electric arc plasma generator is an acute angle.

[0008] The radio frequency plasma generator is provided with a feed port at the central axis.

[0009] A primary collector is provided at the other end of the high-temperature reactor, and a discharge port is also provided on the furnace wall of the high-temperature reactor near the primary collector.

[0010] Both the radio frequency plasma generator and the arc plasma generator use nitrogen as the working gas.

[0011] Furthermore, the furnace wall of the high-temperature reactor consists of a refractory layer, a heat insulation layer, a heat preservation layer, and a cooling jacket, from the inside out.

[0012] A cooling medium inlet is provided at one end of the cooling jacket between the discharge port and the primary collector and near the primary collector, and a cooling medium outlet is provided at the other end of the cooling jacket near the radio frequency plasma generator.

[0013] The high-temperature reactor also has an observation window on the furnace wall near the junction of the flame outlets of the radio frequency plasma generator and the electric arc plasma generator.

[0014] Furthermore, a cooling device is connected to the discharge port, the cooling device comprising a primary cooler and a secondary cooler connected in sequence.

[0015] Furthermore, it also includes a secondary heating system, which includes a heater and a booster pump; the heater includes two air inlets and one air outlet, one air inlet is connected to the cooling medium outlet, and the other air inlet is connected to the air outlet of the booster pump; the air outlet is connected to the working gas storage device.

[0016] The air inlet of the booster pump is connected to the first-stage cooler.

[0017] Furthermore, it also includes a collection system comprising a primary collector, a secondary collector, a dual-chamber glove box collector, and a tertiary collector connected in sequence;

[0018] The inlet of the primary collector is connected to the outlet of the secondary cooler.

[0019] Furthermore, each collection chamber of the dual-chamber glove box collector includes a nitrogen injection port.

[0020] Furthermore, it also includes a vacuum pump, the inlet of which is connected to the outlet of the three-stage collector.

[0021] Secondly, a nitride production process based on a radio frequency plasma generator is provided, which is applied to the aforementioned nitride production equipment based on a radio frequency plasma generator; including the following steps:

[0022] Nitrogen gas is introduced into the high-temperature reactor until the reaction chamber is filled with a pure nitrogen atmosphere;

[0023] Using nitrogen as the working gas, both the radio frequency plasma generator and the electric arc plasma generator are turned on to heat the reaction chamber of the high-temperature reactor; when the temperature inside the reaction chamber of the high-temperature reactor reaches the first preset temperature value, the electric arc plasma generator is turned off.

[0024] After the arc plasma generator is turned off, the feeding begins. The micron-sized powder material fed in through the feed inlet is transformed into nano-sized high-temperature particles by the radio frequency plasma generator.

[0025] Nitride powder is obtained by contacting nanoscale high-temperature particles with nitrogen plasma.

[0026] Furthermore, while simultaneously activating both the radio frequency plasma generator and the arc plasma generator to heat the reaction chamber of the high-temperature reactor using nitrogen as the working gas, the cooling circuit of the high-temperature reactor also enters the working state.

[0027] Furthermore, after shutting down the arc plasma generator, the temperature inside the reaction chamber is continuously monitored. Whenever the temperature inside the reaction chamber is lower than the second preset temperature value, the arc plasma generator is turned on with nitrogen as the working gas until the temperature inside the reaction chamber reaches the first preset temperature value, and then the arc plasma generator is turned off again.

[0028] The beneficial effects of this invention are as follows:

[0029] Nitrides prepared using a radio frequency plasma generator with nitrogen as the working gas have advantages such as high purity, good particle size consistency, and high sphericity. Furthermore, the arrangement of the high-temperature reactor and the radio frequency plasma generator allows the temperature of the high-temperature reactor to gradually decrease from top to bottom. This temperature gradient is beneficial for aluminum nitride in a high-temperature state to achieve rapid quenching as it moves from the top to the bottom of the high-temperature reactor, thereby inhibiting particle growth and crystallization. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the main equipment structure of the nitride production equipment based on the radio frequency plasma generator of the present invention.

[0031] Figure 2 This is a flowchart of the nitride production process based on a radio frequency plasma generator according to the present invention.

[0032] Reference numerals: 1-Radio frequency plasma generator, 2-Arc plasma generator, 3-High temperature reactor, 4-Inlet, 5-Primary collector, 6-Outlet, 7-Refractory layer, 8-Insulation layer, 9-Heat insulation layer, 10-Cooling jacket, 11-Observation window, 12-First stage cooler, 13-Heater, 14-Increase air pump, 15-Air inlet, 16-Cooling medium inlet, 17-Cooling medium outlet, 18-Water-cooled flange. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Currently, the main synthesis methods for the industrial production of aluminum nitride powder include direct nitriding and carbothermic reduction. Direct nitriding involves heating aluminum powder directly in a nitrogen atmosphere, causing the aluminum powder to react with nitrogen to form aluminum nitride. Because aluminum powder is easily combustible at high temperatures, and the nitriding reaction is slow at low temperatures, this method requires precise temperature control, and the synthesized AlN suffers from low purity, poor controllability, and high energy consumption. Carbothermic reduction involves heating alumina and carbon powder in a nitrogen atmosphere to produce aluminum nitride through a carbothermic reduction reaction. This method has a complex process flow, produces byproducts such as carbon monoxide and carbon dioxide during the reaction, and may introduce carbon impurities, making it difficult to control the purity of the aluminum nitride.

[0035] It is evident that existing mainstream methods still present considerable challenges in controlling the quality (such as purity) of aluminum nitride preparations. Based on research into the application of plasma generators, this invention proposes a nitride preparation method and related equipment based on a radio frequency plasma generator 1. Please refer to the subsequent specific embodiments for details. It should be noted that the following embodiments all use the preparation of aluminum nitride as an example.

[0036] Example 1

[0037] Nitride (aluminum nitride in this embodiment) production equipment based on radio frequency plasma generator 1, such as Figure 1 As shown; including:

[0038] A high-temperature reactor 3 is provided with a radio frequency plasma generator 1 at one end of the high-temperature reactor 3. An arc plasma generator 2 is also provided on the furnace wall of the high-temperature reactor 3 near the radio frequency plasma generator 1. The flame outlets of the radio frequency plasma generator 1 and the arc plasma generator 2 are both located inside the high-temperature reactor 3, and the angle between the flame outlet directions of the radio frequency plasma generator 1 and the arc plasma generator 2 is an acute angle.

[0039] In practical applications, the plasma flame generated by the radio frequency plasma generator 1 reaches approximately 3000 °C, a temperature sufficient to easily vaporize micron-sized aluminum powder into nano-sized aluminum particles. While this setup can produce aluminum nitride without the additional arc plasma generator 2, the reaction chamber needs to be maintained within a specific temperature range, such as around 1200 °C (primarily the temperature at the center of the reaction chamber). Therefore, once the temperature inside the reaction chamber drops to a preset value (the second preset temperature), the power of the radio frequency plasma generator 1 needs to be increased to raise the temperature back to approximately 1200 °C. However, frequent adjustments to the output power of the radio frequency plasma generator 1 significantly impact its lifespan, resulting in a limited production duration for aluminum nitride. Therefore, adding an additional arc plasma generator 2 to heat the reaction chamber is a more preferable solution.

[0040] Building upon the above, setting the angle between the flame exit directions of the radio frequency plasma generator 1 and the arc plasma generator 2 to an acute angle creates a strong and stable vortex zone downstream of the intersection point. This enhances turbulence intensity, ensuring that aluminum nanoparticles and active nitrogen or nitrogen ions are violently and rapidly mixed in three-dimensional space. This breaks down any potential laminar flow or concentration stratification, maximizing the reaction contact area and resulting in a more uniform and thorough reaction. Simultaneously, the presence of the vortex zone extends the effective residence time of aluminum nanoparticles and aluminum nitride particles in the high-temperature region. They no longer simply pass through in a straight line but circulate and react within the vortex, which helps improve the reaction conversion rate.

[0041] In other words, when the radio frequency plasma generator 1 and the arc plasma generator 2 work simultaneously, they can generate an eddy current region, which increases the aluminum nitride production efficiency. In order to retain this eddy current region for as long as possible, the second preset temperature value can be set slightly higher (it is 1200 ℃ lower than the first preset temperature value) to shorten the start-up interval of the arc plasma generator 2. In this case, the arc plasma generator 2 needs to meet the performance requirements of high-frequency start-up.

[0042] Since it is used to prepare nitrides, such as aluminum nitride, both the radio frequency plasma generator 1 and the arc plasma generator 2 use nitrogen as the working gas to generate nitrogen plasma with high reactivity, thereby accelerating the reaction of aluminum nitride.

[0043] A feed inlet 4 is provided at the central axis of the radio frequency plasma generator 1. In order to enable micron-sized aluminum powder to be rapidly and uniformly vaporized into nano-sized particles, an ultrasonic dispersion device or an airflow dispersion device can be installed at the feed inlet 4 to ensure that the aluminum powder enters the plasma flame generated by the radio frequency plasma generator 1 in a highly dispersed "mist" form, avoiding the formation of clumps, thereby achieving uniform vaporization and generating monodisperse aluminum nanoparticles.

[0044] A primary collector 5 is installed at the other end of the high-temperature reactor 3, and a discharge port 6 is also provided on the furnace wall of the high-temperature reactor 3 near the primary collector 5. A feeder is installed at the discharge port 6 of the primary collector 5. This feeder adopts a dual-valve design. When the first valve is opened, the powder falls into the storage bin section between the first and second valves. Closing the first valve and then opening the second valve allows the powder stored in the storage bin section to be retrieved. This dual-valve design allows for online material retrieval without affecting the continuous operation of the preparation equipment.

[0045] Since the reaction chamber in the high-temperature reactor 3 needs to vaporize aluminum powder and produce aluminum nitride, the high-temperature reactor 3 needs to withstand high temperatures. To ensure the sustainable production of aluminum nitride, its furnace wall consists of a refractory layer 7, a heat insulation layer 8, a thermal insulation layer 9, and a cooling interlayer 10, from the inside out. The materials used for the refractory layer 7, the heat insulation layer 8, and the thermal insulation layer 9 are not special, and the materials can be replaced depending on the type of nitride to be produced (different nitrides require different temperatures in the reaction chamber).

[0046] A cooling medium inlet 16 is provided at one end of the cooling jacket 10 between the discharge port 6 and the primary collector 5, and a cooling medium outlet 17 is provided at the other end of the cooling jacket 10 near the radio frequency plasma generator 1. To achieve rapid cooling and a gradual temperature decrease from top to bottom in the high-temperature reactor 3, this temperature gradient facilitates rapid quenching of the aluminum nitride at high temperatures as it moves from the upper part of the reactor to the lower part, thereby inhibiting particle growth and crystallization. Therefore, the cooling medium inlet 16 is located at the lower part of the high-temperature reactor 3, and the outlet is located at the upper part. In this embodiment, liquid nitrogen is used as the cooling medium. After being pumped into the cooling jacket 10 at the lower part of the high-temperature reactor 3, the liquid nitrogen rapidly absorbs heat and vaporizes to form nitrogen gas, which is then discharged from the cooling medium outlet 17.

[0047] To allow observation of the reaction chamber, the high-temperature reactor 3 has an observation window 11 installed on the furnace wall near the flame junction of the radio frequency plasma generator 1 and the arc plasma generator 2. The observation window 11 extends through the furnace wall and connects to the reaction chamber. Due to the high temperature, a cooling layer (water cooling is acceptable) is also applied to the wall of the observation window 11 channel. Since the temperature inside the reaction chamber needs continuous monitoring, a temperature sensor is also installed within the chamber. To increase the sensor's lifespan, it is positioned within the observation window 11 channel, close to the reaction chamber, where the temperature is slightly lower than the internal temperature. To ensure the temperature sensor accurately reflects the reaction chamber temperature, calibration is required before production. This involves measuring the temperature difference between the middle section of the reaction chamber during production and the temperature collected by the sensor at the aforementioned location. Compensation is then performed based on this difference to accurately reflect the internal temperature of the reaction chamber.

[0048] In addition to the aforementioned temperature sensor placement locations, the temperature sensor can also be directly placed on the inner wall in the middle of the reaction chamber, allowing for more direct measurement of the temperature within the reaction chamber. It should be noted that because the reaction chamber is cylindrical, and both the frequency plasma generator and the arc plasma generator 2 are located within one section, the temperature within the reaction chamber will not be uniform during actual production. The temperature gradually decreases from one end (where the frequency plasma generator and arc plasma generator 2 are installed) to the other end. Therefore, the monitored temperatures in this embodiment are based on the temperature in the middle of the reaction chamber.

[0049] The discharge port 6 is located at the lower part of the high-temperature reactor 3 (i.e., at the end away from the radio frequency plasma generator 1). As mentioned above, the direction in which the temperature in the reaction chamber gradually decreases (here, the direction from the end where the radio frequency plasma generator 1 is installed to the other end) is consistent with the discharge direction of the reaction product nitride, which is conducive to the rapid quenching of aluminum nitride at high temperature, thereby inhibiting particle growth and crystallization.

[0050] Although liquid nitrogen is introduced through the cooling medium inlet 16 near the discharge port 6 to reduce the temperature of the reaction chamber near the discharge port 6, the quenching effect at this point is limited. In order to further suppress the growth and crystallization of aluminum nitride particles, a cooling device is first connected at the discharge port 6 before collection. The cooling device includes a primary cooler 12 and a secondary cooler connected in sequence.

[0051] The primary cooling unit 12 is an air-cooled cooling unit, and the working gas of the air-cooled cooling unit is nitrogen. The secondary cooling unit is a condenser; after passing through the primary cooling unit 12 and the secondary cooling unit, the aluminum nitride powder and nitrogen are rapidly quenched and cooled to 100 to 150 ℃ before entering the subsequent collection device.

[0052] After quenching, the resulting aluminum nitride powder is relatively stable. Gas containing the aluminum nitride powder is then introduced into the collection system through the outlet of the secondary cooler. The collection system consists of a primary collector, a secondary collector, a double-chamber glove box collector, and a tertiary collector connected in sequence. Specifically, the inlet of the primary collector is connected to the outlet of the secondary cooler. It should be noted that the discharge ports 6 of the primary, secondary, and tertiary collectors are all equipped with the same feeders as the primary collector 5, for online material collection. Furthermore, the primary and secondary collectors are actually cyclone separation collection devices. Each collection chamber of the double-chamber glove box collector includes a nitrogen injection port. By introducing nitrogen, the ultrafine aluminum nitride powder from the reactor is always in a nitrogen environment, preventing oxidation-reduction reactions due to oxygen contact, thus further ensuring its purity. The double-chamber glove box operates on a one-for-one standby principle. When one chamber is in ash discharge (aluminum nitride) mode, the other can filter and collect powder in the system; the two collection boxes can be used alternately.

[0053] Understandably, in order to enable the products and gases in the reaction chamber to quickly enter the cooling and collection devices, a vacuum pump is connected to the outlet of the three-stage collector. The residence time of the nitride in the reaction chamber can be controlled by the vacuum pump's suction rate, thereby accelerating the flow rate of the nitride and gas in the entire system.

[0054] It should be noted that the entire equipment, from the secondary cooler to the final vacuum pump, utilizes existing technologies, such as the gas-powder cooler, primary separator, secondary separator, pre-collector, post-collector, and vacuum pump unit described in Chinese Invention Patent 2022103950284. This part of the equipment structure does not constitute a technical improvement of this invention.

[0055] To reduce nitrogen usage costs and the number of times the arc plasma generator 2 is started, this invention also includes a secondary heating system for recovering and heating nitrogen. The recovered nitrogen is heated by this secondary heating system and used as the working gas for the radio frequency plasma generator 1, thereby reducing nitrogen consumption. Furthermore, the preheating of the nitrogen effectively reduces the rate of temperature drop within the reaction chamber. Specifically, the secondary heating system includes a heater 13 and a booster pump. The heater 13 includes two inlets 15 and one outlet. One inlet 15 is connected to the cooling medium outlet 17 to recover nitrogen generated after heat exchange in the cooling jacket 10. The other inlet 15 is connected to the outlet of the booster pump. The outlet is connected to a working gas storage device. The inlet 15 of the booster pump is connected to the primary cooler 12. A filter layer is also provided at the inlet 15 of the booster pump for filtering the prepared aluminum nitride powder.

[0056] It is understandable that the outlet of heater 13 can also be connected to a separate gas storage device, which can directly supply working gas to radio frequency plasma generator 1 or arc plasma generator 2. The heater 13 contains porous graphite material, which increases the gas travel path and allows for more thorough heating. An electric heating wire is installed inside the housing of heater 13, heating the graphite inside the heater 13 by energizing it. The two air inlets 15 of heater 13 are located at opposite ends, thus the outlet is located in the middle of heater 13; a booster suction pump is also installed in the external connecting pipeline of the outlet.

[0057] It should also be noted that when the height of the high-temperature reactor 3 needs to be increased, the two sections of the reactor can be connected by a flange with water cooling to increase the height of the high-temperature reactor 3; the increase in the height of the reactor means that the reaction channel for producing aluminum nitride is longer, which is conducive to a more complete reaction.

[0058] Example 2

[0059] This embodiment, based on the equipment provided in Embodiment 1, proposes a nitride production process based on the radio frequency plasma generator 1, such as... Figure 2 As shown, it includes the following steps:

[0060] Nitrogen gas is introduced into the high-temperature reactor 3 until the reaction chamber is filled with a pure nitrogen atmosphere; this is to prevent other gases from entering and causing a decrease in the purity of the generated aluminum nitride.

[0061] Using nitrogen as the working gas, the radio frequency plasma generator 1 and the electric arc plasma generator 2 are simultaneously turned on to heat the reaction chamber of the high-temperature reactor 3; when the temperature in the reaction chamber of the high-temperature reactor 3 reaches the first preset temperature value, the electric arc plasma generator 2 is turned off.

[0062] In this embodiment for producing aluminum nitride, the radio frequency plasma generator 1 has a power of 100 kW, which can raise the plasma temperature to 3000 ℃. Since radio frequency plasma has no electrode contamination, it is the primary heat source for vaporizing micron-sized aluminum powder. The arc plasma generator 2 in this embodiment has a power of 50-70 kW and its function is to assist in heating, ensuring that the temperature inside the reactor is maintained between a second preset temperature value and a first preset temperature value. In this embodiment, the first preset temperature value is 1200 ℃, and the second preset temperature value can be 800 ℃. It should be noted that although the plasma flame temperature of the radio frequency plasma generator 1 is as high as 3000 ℃, it requires a large amount of heat to vaporize aluminum powder, and the reaction chamber of the high-temperature reactor 3 is also large. In addition, the high-temperature reactor 3 also has a cooling system to protect the furnace wall from being burned. Therefore, even though the production of aluminum nitride is an exothermic reaction, the temperature inside the reactor is difficult to maintain at 1200 ℃ without the supplement of other heat sources or an increase in the power of the radio frequency plasma generator 1. Therefore, the arc plasma generator 2 is required to provide supplementary heating.

[0063] After the arc plasma generator 2 is turned off, the feeding begins. The micron-sized powder material fed in through the feed port 4 is transformed into nano-sized high-temperature aluminum particles by the radio frequency plasma generator 1. The nano-sized high-temperature particles come into contact with nitrogen plasma to obtain nitride powder.

[0064] Since both nanoscale high-temperature aluminum particles and nitrogen plasma have high activity, they can increase the reaction rate, thereby rapidly and fully generating micron-sized or even nanoscale aluminum nitride powder.

[0065] It should be further explained that, based on the above, further increasing the power of the radio frequency plasma generator 1 to make the plasma flame it produces have a higher temperature can make the generated powder finer.

[0066] While simultaneously activating both the radio frequency plasma generator 1 and the arc plasma generator 2 to heat the reaction chamber of the high-temperature reactor 3 using nitrogen as the working gas, the cooling circuit of the high-temperature reactor 3 also enters its operational state. This is to prevent the furnace wall of the high-temperature reactor 3 from being eroded, which would affect production. At the same time, once the cooling circuit of the high-temperature reactor 3 is operational, the temperature of the high-temperature reactor 3 gradually decreases from top to bottom, causing the produced aluminum nitride to gradually move from the high-temperature zone to the low-temperature zone (meaning the temperature of the low-temperature zone, compared to the high-temperature zone, is still around 600-800 ℃), achieving preliminary quenching.

[0067] After the arc plasma generator 2 is turned off, the temperature inside the reaction chamber is continuously monitored. Whenever the temperature inside the reaction chamber is lower than the second preset temperature value (as mentioned above, 800 ℃ in this embodiment), the arc plasma generator 2 is turned on with nitrogen as the working gas until the temperature inside the reaction chamber reaches the first preset temperature value (as mentioned above, 1200 ℃ in this embodiment), and then the arc plasma generator 2 is turned off again.

[0068] To further explain the working process of this invention, the decision-making method and basis for material feeding control are further explained. While detecting the temperature within the reaction chamber, it is also necessary to obtain the rate of temperature decrease within the reaction chamber based on the temperature monitoring data. When the rate of temperature decrease within the reaction chamber exceeds a first preset threshold, the feeding rate needs to be slowed down; that is, the feeding rate is inversely proportional to the rate of temperature decrease within the reaction chamber. It can be understood that if the rate of temperature decrease within the reaction chamber is slow (in actual production, a second preset threshold is set, i.e., the rate of temperature decrease within the reaction chamber is less than the second preset threshold), it means that the amount of material fed is insufficient, and in this case, the amount of material fed needs to be increased.

[0069] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A nitride production device based on a radio frequency plasma generator (1), characterized in that, include: A high-temperature reactor (3) is provided with a radio frequency plasma generator (1) at one end of the high-temperature reactor (3). An electric arc plasma generator (2) is also provided on the furnace wall of the high-temperature reactor (3) near the radio frequency plasma generator (1). The flame outlets of the radio frequency plasma generator (1) and the electric arc plasma generator (2) are both located inside the high-temperature reactor (3), and the angle between the flame outlet directions of the radio frequency plasma generator (1) and the electric arc plasma generator (2) is an acute angle. The radio frequency plasma generator (1) has a feed inlet (4) at its central axis; A primary collector (5) is provided at the other end of the high-temperature reactor (3), and a discharge port (6) is also provided on the furnace wall of the high-temperature reactor (3) near the primary collector (5); a cooling device is connected to the discharge port (6), and the cooling device includes a first-stage cooler (12) and a second-stage cooler connected in sequence. Both the radio frequency plasma generator (1) and the arc plasma generator (2) use nitrogen as the working gas. It also includes a secondary heating system, which includes a heater (13) and a booster pump; the heater (13) includes two air inlets (15) and one air outlet, one of the air inlets (15) is connected to the cooling medium outlet (17), and the other air inlet (15) is connected to the air outlet of the booster pump; the air outlet is connected to the working gas storage device. The air inlet (15) of the booster pump is connected to the first-stage cooler (12).

2. The nitride production equipment based on the radio frequency plasma generator (1) as described in claim 1, characterized in that, The furnace wall of the high-temperature reactor (3) consists of a refractory layer (7), a heat insulation layer (8), a heat preservation layer (9), and a cooling jacket (10) from the inside out. A cooling medium inlet (16) is provided at one end of the cooling jacket (10) between the discharge port (6) and the primary collector (5) and near the primary collector (5), and a cooling medium outlet (17) is provided at the other end of the cooling jacket (10) near the radio frequency plasma generator (1). The high-temperature reactor (3) is also provided with an observation window (11) on the furnace wall near the junction of the flame outlets of the radio frequency plasma generator (1) and the electric arc plasma generator (2).

3. The nitride production equipment based on the radio frequency plasma generator (1) as described in claim 2, characterized in that, It also includes a collection system, which comprises a primary collector, a secondary collector, a dual-chamber glove box collector, and a tertiary collector connected in sequence. The inlet of the primary collector is connected to the outlet of the secondary cooler.

4. The nitride production equipment based on the radio frequency plasma generator (1) as described in claim 3, characterized in that, Each collection chamber of the dual-chamber glove box collector includes a nitrogen injection port.

5. The nitride production equipment based on the radio frequency plasma generator (1) as described in claim 3, characterized in that, It also includes a vacuum pump, the inlet (15) of which is connected to the outlet of the three-stage collector.

6. A nitride production process based on a radio frequency plasma generator, characterized in that, The method is applied to the nitride production equipment based on the radio frequency plasma generator (1) as described in any one of claims 1-5, comprising the following steps: Nitrogen gas is introduced into the high-temperature reactor (3) until the reaction chamber is filled with a pure nitrogen atmosphere; Using nitrogen as the working gas, the radio frequency plasma generator (1) and the electric arc plasma generator (2) are turned on simultaneously to heat the reaction chamber of the high-temperature reactor (3); when the temperature in the reaction chamber of the high-temperature reactor (3) reaches the first preset temperature value, the electric arc plasma generator (2) is turned off. After the arc plasma generator (2) is turned off, the feeding begins. The micron-sized powder material fed in through the feed inlet (4) is transformed into nano-sized high-temperature particles by the radio frequency plasma generator (1). Nitride powder is obtained by contacting nano-sized high-temperature particles with nitrogen plasma. After the arc plasma generator (2) is turned off, the temperature inside the reaction chamber is continuously monitored. Whenever the temperature inside the reaction chamber is lower than the second preset temperature value, the arc plasma generator (2) is turned on with nitrogen as the working gas until the temperature inside the reaction chamber reaches the first preset temperature value and then the arc plasma generator (2) is turned off again.

7. The nitride production process based on a radio frequency plasma generator as described in claim 6, characterized in that, At the same time that the radio frequency plasma generator (1) and the arc plasma generator (2) are turned on simultaneously with nitrogen as the working gas to heat the reaction chamber of the high-temperature reactor (3), the cooling circuit of the high-temperature reactor (3) enters the working state.

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