阅读说明：本技术 包覆型复合粉体制备方法与制备装置 (Coated composite powder preparation method and preparation device ) 是由 严大洲 杨涛 刘诚 孙强 万烨 司文学 张升学 于 2021-07-15 设计创作，主要内容包括：本发明公开了一种包覆型复合粉体制备方法与制备装置,包覆型复合粉体制备方法,包括以下步骤：A)对管式反应器进行加热,以便管式反应器内的温度达到反应温度；B)将硅基反应气体和载气混合,以便得到混合气体,并将混合气体通入管式反应器内；C)利用等离子单元对进入管式反应器内的混合气体等离子化,以便加强混合气体的化学反应活性；D)等离子化后的硅基反应气体在管式反应器内热分解以便产生硅粒；E)将碳基反应气体通入管式反应器内热分解以便产生碳原子,碳原子在硅粒的表面沉积形成包覆层以便产生复合粉体；和F)分离、并收集复合粉体。本发明的包覆型复合粉体制备方法具有生产成本低、能耗低、可持续生产和便于规模化生产的优点。(The invention discloses a preparation method and a preparation device of coated composite powder, and the preparation method of the coated composite powder comprises the following steps: A) heating the tubular reactor so that the temperature in the tubular reactor reaches a reaction temperature; B) mixing silicon-based reaction gas with carrier gas to obtain mixed gas, and introducing the mixed gas into a tubular reactor; C) plasmatizing the mixed gas entering the tubular reactor by using a plasma unit so as to enhance the chemical reaction activity of the mixed gas; D) thermally decomposing the plasmatized silicon-based reaction gas in the tubular reactor to generate silicon particles; E) introducing carbon-based reaction gas into the tubular reactor for thermal decomposition so as to generate carbon atoms, and depositing the carbon atoms on the surface of the silicon particles to form a coating layer so as to generate composite powder; and F) separating and collecting the composite powder. The preparation method of the coated composite powder has the advantages of low production cost, low energy consumption, sustainable production and convenience for large-scale production.)

1. A preparation method of coated composite powder is characterized by comprising the following steps:

A) heating the tubular reactor so that the temperature in the tubular reactor reaches a reaction temperature;

B) mixing silicon-based reaction gas with carrier gas to obtain mixed gas, and introducing the mixed gas into the tubular reactor;

C) plasmatizing the mixed gas entering the tubular reactor by using a plasma unit so as to enhance the chemical reaction activity of the mixed gas;

D) thermally decomposing the silicon-based reaction gas after the plasma treatment in the tubular reactor to produce silicon particles;

E) introducing carbon-based reaction gas into the tubular reactor for thermal decomposition so as to generate carbon atoms, and depositing the carbon atoms on the surfaces of the silicon particles to form coating layers so as to generate composite powder; and

F) separating and collecting the composite powder.

2. The method for preparing the coated composite powder according to claim 1, wherein the step a) comprises:

a-1) closing the gas inlet of the tubular reactor;

a-2) vacuumizing the tubular reactor;

a-3) stopping vacuumizing, opening a gas inlet of the tubular reactor, and filling inert gas into the tubular reactor; and

a-4) heating the tubular reactor so that the temperature in the tubular reactor reaches the reaction temperature;

optionally, the inert gas is nitrogen or argon;

optionally, step A-1), step A-2) and step A-3) are repeated at least 3 times.

3. The method for preparing the coated composite powder according to claim 2, wherein the step B) comprises:

b-1) gasifying a liquid silicon-based raw material so as to obtain the silicon-based reaction gas; and

b-2) mixing the silicon-based reaction gas with the carrier gas to obtain the mixed gas, and introducing the mixed gas into the tubular reactor;

optionally, the silicon-based reaction gas is one of silane, dichlorosilane, trichlorosilane and silicon tetrachloride, and the carbon-based reaction gas is one of acetylene, methane, toluene and ethanol.

4. The method for preparing the coated composite powder of claim 1, wherein the reaction temperature is between 300 ℃ and 1300 ℃.

5. The method for preparing the coated composite powder according to claim 1, wherein the step F) comprises cleaning the composite powder with nitrogen or argon in a vacuum environment, separating, and collecting the composite powder.

6. A coated composite powder preparation device is characterized by comprising:

a gas mixer having a first gas inlet, a second gas inlet, and a first gas outlet;

the tubular reactor is provided with a third air inlet, a fourth air inlet and a first discharge hole, the third air inlet is connected with the first air outlet, and the fourth air inlet is positioned between the third air inlet and the first discharge hole in the length direction of the tubular reactor;

the plasma device comprises a radio frequency power supply and a radio frequency coil, and the radio frequency coil is sleeved on the tubular reactor;

the heating device comprises a heating element and a temperature sensor, the heating element is sleeved on the tubular reactor, and the radio frequency coil is positioned between the heating element and the third air inlet in the length direction of the tubular reactor;

the collector is provided with a first feeding hole, a second discharging hole and a second gas outlet, and the first feeding hole is connected with the first discharging hole; and

and the exhaust device comprises a vacuum generator and a filter, the inlet of the filter is connected with the second air outlet, and the outlet of the filter is connected with the inlet of the vacuum generator.

7. The coated composite powder preparation device as claimed in claim 6, wherein the tubular reactor is vertically or obliquely arranged, the third inlet is located at the upper end of the tubular reactor, the first outlet is located at the lower end of the tubular reactor, and the fourth inlet is located on the sidewall of the tubular reactor.

8. The coated composite powder production apparatus as claimed in claim 7, wherein a plurality of fourth gas inlets are provided in the longitudinal direction of the tubular reactor.

9. The coated composite powder preparation apparatus as claimed in claim 7 or 8, wherein the tubular reactor further comprises an inlet manifold, and an outlet of the inlet manifold is communicated with the fourth inlet.

10. The coated composite powder production apparatus according to claim 7, further comprising:

the liquid evaporation device comprises a first liquid inlet and a third air outlet, and the third air outlet is connected with the first air inlet; and

a mass flow meter cooperating with the gas mixer;

optionally, the liquid evaporation apparatus comprises a flash evaporator and a bubbler.

Technical Field

The invention relates to the field of powder preparation, in particular to a preparation method and a preparation device of coated composite powder.

Background

The cladding composite material combines single materials with different characteristics into a heterostructure in the form of a matrix and a cladding layer, obtains comprehensive excellent performance superior to that of the single material, and meets the requirement of multiple characteristics of the material in a specific application scene. The preparation process of the coated composite powder material is an important material production technology, has important significance for heterostructure materials with special functions, and is an important way for solving the application bottleneck of the silicon-based negative electrode material, but the existing process still has a plurality of defects, such as poor product composite effect, low production efficiency, high production cost and the like.

In the related art, the cladding type composite method is roughly classified into a physical method and a chemical method. The physical method mainly refers to that a mechanical treatment mode such as stirring or grinding is utilized to physically mix the base material and the coating material, and external input energy is used for combining the base material and the coating material together or embedding the base material into a coating medium (the composite material obtained by the mode has weak mutual acting force and cannot achieve the optimal performance of the material). The physical method for preparing the silicon-carbon composite material is to directly add carbon powder to carry out co-grinding in the process of mechanically grinding silicon powder, and high energy is often input from the outside to form a composite structure of silicon and carbon. In addition, the matrix and the coating layer are compounded mainly by Van der Waals force, the binding force is weak, an ideal coating or embedding structure cannot be formed, and the silicon-carbon composite powder is used for preparing silicon-carbon composite powder and has a limited effect on improving the performance of a silicon-based negative electrode.

The chemical method mainly comprises a liquid phase method and a gas phase method, and the principle is that a coating material or a coating material precursor is covered on a substrate through a specific physical and chemical process, and a compact heterogeneous composite structure is formed between the substrate and the coating through post-treatment. For example, in the preparation of coated silicon-carbon composite powder material, the liquid phase method generally coats silicon powder with an organic carbon source and then forms a silicon-carbon composite structure through drying and thermal decomposition, or the gas phase method directly deposits carbon layer on the surface of silicon particles to form a composite material through thermal decomposition with hydrocarbon gas as a raw material. The chemical method product silicon-carbon has tight effect and strong binding force, can greatly improve the electrical conductivity of silicon, and simultaneously the carbon layer provides additional mechanical support for silicon particles, can enhance the mechanical property of the particles and inhibit the structural damage. However, the chemical method compounding currently has a high technical barrier on the process and product quality control, and has the problems of poor production continuity and small processing scale and relatively high cost in the aspect of engineering.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, the embodiment of the invention provides a preparation method and a preparation device of coated composite powder.

The preparation method of the coated composite powder provided by the embodiment of the invention comprises the following steps:

A) heating the tubular reactor so that the temperature in the tubular reactor reaches a reaction temperature;

B) mixing silicon-based reaction gas with carrier gas to obtain mixed gas, and introducing the mixed gas into the tubular reactor;

C) plasmatizing the mixed gas entering the tubular reactor by using a plasma unit so as to enhance the chemical reaction activity of the mixed gas;

D) thermally decomposing the silicon-based reaction gas after the plasma treatment in the tubular reactor to produce silicon particles;

E) introducing carbon-based reaction gas into the tubular reactor for thermal decomposition so as to generate carbon atoms, and depositing the carbon atoms on the surfaces of the silicon particles to form coating layers so as to generate composite powder; and

F) separating and collecting the composite powder.

Therefore, the preparation method of the composite powder provided by the embodiment of the invention has the advantages of low production cost, low energy consumption, sustainable production and convenience for large-scale production.

In some embodiments, the step a) comprises:

a-1) closing the gas inlet of the tubular reactor;

a-2) vacuumizing the tubular reactor;

a-3) stopping vacuumizing, opening a gas inlet of the tubular reactor, and filling inert gas into the tubular reactor; and

a-4) heating the tubular reactor so that the temperature in the tubular reactor reaches the reaction temperature;

optionally, the inert gas is nitrogen or argon;

optionally, step A-1), step A-2) and step A-3) are repeated at least 3 times.

In some embodiments, said step B) comprises:

b-1) gasifying a liquid silicon-based raw material so as to obtain the silicon-based reaction gas; and

b-2) mixing the silicon-based reaction gas with the carrier gas to obtain the mixed gas, and introducing the mixed gas into the tubular reactor;

optionally, the silicon-based reaction gas is one of silane, dichlorosilane, trichlorosilane and silicon tetrachloride, and the carbon-based reaction gas is one of acetylene, methane, toluene and ethanol.

In some embodiments, the reaction temperature is between 300 ℃ and 1300 ℃.

In some embodiments, the step F) includes cleaning the composite powder using nitrogen or argon in a vacuum environment, separating, and collecting the composite powder.

The invention also provides a coated composite powder preparation device, which comprises:

a gas mixer having a first gas inlet, a second gas inlet, and a first gas outlet;

the tubular reactor is provided with a third air inlet, a fourth air inlet and a first discharge hole, the third air inlet is connected with the first air outlet, and the fourth air inlet is positioned between the third air inlet and the first discharge hole in the length direction of the tubular reactor;

the plasma device comprises a radio frequency power supply and a radio frequency coil, and the radio frequency coil is sleeved on the tubular reactor;

the heating device comprises a heating element and a temperature sensor, the heating element is sleeved on the tubular reactor, and the radio frequency coil is positioned between the heating element and the third air inlet in the length direction of the tubular reactor;

the collector is provided with a first feeding hole, a second discharging hole and a second gas outlet, and the first feeding hole is connected with the first discharging hole; and

and the exhaust device comprises a vacuum generator and a filter, the inlet of the filter is connected with the second air outlet, and the outlet of the filter is connected with the inlet of the vacuum generator.

In some embodiments, the tubular reactor is vertically or obliquely arranged, the third gas inlet is located at the upper end of the tubular reactor, the first discharge outlet is located at the lower end of the tubular reactor, and the fourth gas inlet is located on the side wall of the tubular reactor.

In some embodiments, the fourth gas inlet is provided in plurality in the length direction of the tubular reactor.

In some embodiments, the pipe reactor further comprises an inlet manifold, an outlet of the inlet manifold being in communication with the fourth inlet port.

The coated composite powder preparation device according to the embodiment of the invention further comprises:

the liquid evaporation device comprises a first liquid inlet and a third air outlet, and the third air outlet is connected with the first air inlet; and

a mass flow meter cooperating with the gas mixer;

optionally, the liquid evaporation apparatus comprises a flash evaporator and a bubbler.

Drawings

Fig. 1 is a schematic view of a coated composite powder production apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a gas mixer according to an embodiment of the invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

The preparation method of the coated composite powder provided by the embodiment of the invention comprises the following steps:

A) the tubular reactor 20 is heated so that the temperature inside the tubular reactor 20 reaches the reaction temperature.

B) The silicon-based reaction gas and the carrier gas are mixed to obtain a mixed gas, and the mixed gas is introduced into the tubular reactor 20.

C) The mixed gas entering the pipe reactor 20 is plasmatized by the plasma unit so as to enhance the chemical reactivity of the mixed gas.

D) The plasmatized silicon-based reaction gas is thermally decomposed in the tubular reactor 20 to generate silicon particles.

E) Carbon-based reaction gas is introduced into the tubular reactor 20 to be thermally decomposed so as to generate carbon atoms, and the carbon atoms are deposited on the surfaces of the silicon particles to form coating layers so as to generate the composite powder.

F) Separating and collecting the composite powder.

In the related technology, the physical method matrix and the coating layer in the coating type composite method are mainly compounded by Van der Waals force, the bonding force is weak, an ideal coating or embedding structure cannot be formed, and the coating type composite method is used for preparing silicon-carbon composite powder and has a limited effect on improving the performance of a silicon-based negative electrode. The chemical method compounding has a high technical barrier on the process and product quality control, and has the problems of poor production continuity, small treatment scale and relatively high cost in the aspect of engineering.

According to the preparation method of the coated composite powder, silicon-based reaction gas and carbon-based reaction gas are used as raw materials, silicon particles generated by the silicon-based reaction gas in the tubular reactor 20 are used as a matrix, and carbon atoms generated by the carbon-based reaction gas in the tubular reactor 20 are deposited as a coating layer.

The mixed gas of the silicon-based reaction gas and the carrier gas is introduced into the tubular reactor 20, and the carrier gas can provide the atmosphere required by the reaction for preparing the silicon particles. The mixed gas entering the pipe reactor 20 is plasmatized by the plasma unit so as to enhance the chemical reactivity of the mixed gas. Namely, the silicon-based reaction gas and the carrier gas entering the tubular reactor 20 are plasmatized by the plasma unit, so that the silicon-based reaction gas and the carrier gas are ionized under the action of the radio-frequency electric field and glow discharge is generated. Besides positive particles and negative particles, a large amount of active groups are generated due to the collision of electrons and gas atoms, so that the chemical activity of the silicon-based reaction gas is enhanced (the chemical reaction rate of the silicon-based reaction gas is increased), namely, the conversion rate of the silicon-based reaction gas is accelerated and the overall conversion efficiency of the reaction system is increased.

After the reaction temperature of the silicon-based reaction gas after the plasma reaction (for enhancing the chemical reaction activity) reaches the reaction temperature, the silicon-based reaction gas is easy to thermally decompose in the tubular reactor 20 to generate silicon particles, that is, after the reaction temperature of the silicon-based reaction gas after the plasma reaction (for enhancing the chemical reaction activity) reaches the reaction temperature, the silicon particles can be generated and serve as a matrix of the coated composite powder.

The carbon-based reaction gas is thermally decomposed in the tubular reactor 20 brought to the reaction temperature to generate carbon atoms. Due to the existence of the silicon nucleus, compared with the carbon atom homogeneous nucleation, the carbon atom is easier to carry out heterogeneous nucleation and deposit on the surface of the silicon particle, so that the carbon atom is deposited on the surface of the silicon particle to form a coating layer so as to generate the composite powder. Separating and collecting the composite powder to complete the preparation of the composite powder. The silicon-based reaction gas and the carbon-based reaction gas are easy to obtain, the production cost is low, no other solid impurities are mixed in the preparation process of the composite powder, continuous production can be realized without interruption, and the obtained composite powder has high purity and is convenient for large-scale production.

Therefore, the preparation method of the coated composite powder provided by the embodiment of the invention has the advantages of low production cost, low energy consumption, sustainable production and convenience for large-scale production.

As shown in fig. 1 and 2, the present invention also proposes a coated composite powder production apparatus 100, and the coated composite powder production apparatus 100 according to an embodiment of the present invention includes a gas mixer 10, a tubular reactor 20, a heating device 30, a plasma device 40, a collector 50, and an exhaust device.

The gas mixer 10 has a first gas inlet 11, a second gas inlet 12 and a first gas outlet 13. The tubular reactor 20 has a third inlet 21, a fourth inlet 22 and a first outlet 23, the third inlet 21 being connected to the first outlet 13. The fourth gas inlet 22 is located between the third gas inlet 21 and the first discharge port 23 in the length direction of the pipe reactor 20.

The plasma device 40 comprises a radio frequency power supply 42 and a radio frequency coil 41, and the radio frequency coil 41 is sleeved on the tubular reactor 20. The heating device 30 comprises a heating element and a temperature sensor, the heating element is sleeved on the tubular reactor 20, and the radio frequency coil 41 is positioned between the heating element and the third air inlet 21 in the length direction of the tubular reactor 20. The collector 50 has a first inlet 51, a second outlet 52 and a second outlet 53, the first inlet 51 being connected to the first outlet 23. And the exhaust device comprises a vacuum generator and a filter, the inlet of the filter is connected with the second air outlet 53, and the outlet of the filter is connected with the inlet of the vacuum generator.

According to the coated composite powder preparation device 100 provided by the embodiment of the invention, the heating device 30 and the plasma device 40 are arranged, and the radio frequency coil 41 is positioned between the heating element and the third air inlet 21 in the length direction of the tubular reactor 20, so that the silicon-based reaction gas and the carrier gas are firstly ionized under the action of the radio frequency electric field and glow discharge is generated. Besides positive particles and negative particles, a large number of active groups are generated due to collision of electrons and gas atoms, so that the chemical activity of the silicon-based reaction gas is enhanced (the chemical reaction rate of the silicon-based reaction gas is increased), namely, the preparation efficiency of silicon particles is increased.

The heating device 30 heats the gas in the tubular reactor 20 to a reaction temperature, and the silicon-based reaction gas and the carbon-based reaction gas after plasma (which enhance chemical reaction activity) reach the reaction temperature and are easily thermally decomposed in the tubular reactor 20. Thus, after the silicon-based reaction gas after plasma ionization (chemical reaction activity enhancement) reaches the reaction temperature, silicon particles are generated after thermal decomposition, carbon atoms are generated after the thermal decomposition of the carbon-based reaction gas reaches the reaction temperature, and the carbon atoms deposit on the surfaces of the silicon particles to form coating layers, so that the coated composite powder is generated.

The collector 50 and the exhaust device are used for separating and collecting the composite powder to complete the preparation of the composite powder. The silicon-based reaction gas and the carbon-based reaction gas are easy to obtain, the production cost is low, no other solid impurities are mixed in the preparation process of the composite powder, intermittent sustainable production is not needed in the middle, and large-scale production is facilitated.

Therefore, the coated composite powder preparation apparatus 100 according to the embodiment of the present invention has the advantages of low production cost, low energy consumption, sustainable production, and convenience for mass production.

The method for producing a coated composite powder according to an embodiment of the present invention is specifically described below.

In some embodiments, step a) comprises:

a-1) closing the air inlet of the tubular reactor 20, preventing air from re-entering the tubular reactor 20.

A-2) evacuating the tubular reactor 20 and drawing out air from the tubular reactor 20.

And A-3) stopping vacuumizing, opening a gas inlet of the tubular reactor, and filling gas in the tubular reactor 20 by using inert gas to further reduce gas impurities in the tubular reactor 20, thereby reducing the pollution of the impurities.

A-4) heating the tubular reactor 20 so that the temperature inside the tubular reactor 20 reaches the reaction temperature, so that the silicon-based reaction gas can be thermally decomposed after entering the tubular reactor 20.

Optionally, the inert gas is nitrogen or argon.

Optionally, the step A-1), the step A-2) and the step A-3) are repeatedly carried out for at least 3 times, so that impurities in the tubular reactor 20 are further reduced, and pollution caused by the impurities in the process of preparing the composite powder is reduced.

In some embodiments, step a) comprises: the inert gas is replaced with a carrier gas (which is not required if both the carrier gas and the inert gas are nitrogen) so that the carrier gas is filled in the tubular reactor 20, the carrier gas being one of nitrogen, argon and hydrogen. The carrier gas can provide the atmosphere required by the reaction for preparing the silicon particles and simultaneously plays a role in conveying the silicon particle products.

Alternatively, the carrier gas is hydrogen, and hydrogen generated after plasma ionization can react with some particles (other than silicon particles) in the silicon-based reaction gas more easily to facilitate silicon particle generation.

In some embodiments, step B) comprises:

b-1) gasifying liquid silicon-based raw material gas so as to obtain silicon-based reaction gas. The raw material cost can be reduced by gasifying cheap liquid silicon-based raw materials so as to obtain silicon-based reaction gas required by the reaction, thereby facilitating the obtaining of gas raw materials.

B-2) mixing the silicon-based reaction gas with a carrier gas to obtain a mixed gas, and introducing the mixed gas into the tubular reactor 20. The mixed gas contains a silicon-based reaction gas and a carrier gas so that the inlet into the tubular reactor 20 has an atmosphere suitable for the reaction to occur.

Optionally, the silicon-based reaction gas is one of silane, dichlorosilane, trichlorosilane, and silicon tetrachloride. For example, when the silicon-based reaction gas is trichlorosilane, trichlorosilane is thermally decomposed to generate silicon particles, hydrogen chloride, silicon tetrachloride and the like. The silicon particles are collected after being prepared into composite powder, and the hydrogen chloride, the silicon tetrachloride and a part of the remaining incompletely reacted trichlorosilane are discharged.

Optionally, the carbon-based reaction gas is one of acetylene, methane, toluene, and ethanol.

In some embodiments, the reaction temperature is between 300 ℃ and 1300 ℃. The silicon-based reaction gas comprises silane, dichlorosilane, trichlorosilane and silicon tetrachloride, the decomposition temperatures of the silane, dichlorosilane, trichlorosilane and silicon tetrachloride are sequentially increased, and the appropriate reaction temperature can be selected according to different silicon-based reaction gases.

In some embodiments, step F) includes cleaning the composite powder with nitrogen or argon in a vacuum environment, separating, and collecting the composite powder, so that the obtained composite powder is purer and the product quality is improved.

In some embodiments, the tubular reactor 20 is vertically disposed or obliquely disposed. The third inlet 21 is located at the upper end of the pipe reactor 20, the first outlet 23 is located at the lower end of the pipe reactor 20, and the fourth inlet 22 is located on the sidewall of the pipe reactor 20. Thereby facilitating the composite powder to be discharged downwards from the tubular reactor 20 after being produced.

In some embodiments, the fourth gas inlet 22 is disposed in plurality along the length of the tubular reactor 20. In the process of preparing the powder, the length of the coating layer or the residence time of the carbon-based reaction gas is adjusted by selecting different fourth gas inlets 22 and introducing the carbon-based reaction gas into the tubular reactor 20 so as to control the thickness of the coating layer of the composite powder. For example, the thickness of the composite powder coating layer is increased as the carbon-based reaction gas passing through the selected fourth gas inlet 22 is closer to the third gas inlet 21 in the longitudinal direction of the tubular reactor 20.

In some embodiments, the pipe reactor 20 further comprises a gas inlet manifold 24, an outlet of the gas inlet manifold 24 is in communication with the fourth gas inlet 22, and the carbon-based reactant gas passes through the gas inlet manifold 24 to the fourth gas inlet 22. For the fourth inlet port 22 located in the region of the heating element in the length direction of the tubular reactor 20, the outlet of the inlet manifold 24 communicates with the fourth inlet port 22 through the heating element.

In some embodiments, the coated composite powder manufacturing apparatus 100 according to embodiments of the present invention further includes a liquid evaporation apparatus and a mass flow meter.

The liquid evaporation device is used for gasifying the liquid precursor into a gas raw material, namely gasifying the liquid silicon-based raw material into a silicon-based reaction gas. The liquid evaporation device comprises a first liquid inlet and a third air outlet, and the third air outlet is connected with the first air inlet 11.

Optionally, the liquid evaporation apparatus comprises a flash evaporator and a bubbler.

The mass flow meter is matched with the gas mixer 10 for metering and controlling the silicon-based reaction gas entering the gas mixer 10, for example, an inlet of the mass flow meter is connected with the third gas outlet, and an outlet of the mass flow meter is connected with the first gas inlet 11. The silicon-based reaction gas after the gasification of the liquid silicon-based raw material is discharged from the third gas outlet, passes through the mass flow meter, and then enters the first gas inlet 11, so as to enter the gas mixer 10. The carrier gas and the auxiliary gas may enter the gas mixer 10 from the second gas inlet 12.

In some embodiments, the tubular reactor 20 is made of quartz or corundum. The first discharge port 23 of the tubular reactor 20 is of a tapered diameter-variable structure, the first discharge port 23 is located at the bottom of the tubular reactor 20, and the tapered diameter-variable structure facilitates the sliding of the composite powder, so that the composite powder can be collected conveniently.

In some embodiments, the heating element is a silicon-molybdenum rod, the silicon-molybdenum rod has unique high-temperature oxidation resistance, and the heating element adopts independent multi-section intelligent program control arrangement with multiple temperature zones, for example, the heating element can ensure that the reaction temperature range of the matrix generation zone is 300-. The shell of the heating unit is a steel shell which is openable, and alumina fiber heat-insulating materials are filled between the steel shell of the heating unit and the tubular reactor 20, so that heat insulation and energy conservation are facilitated.

In some embodiments, the frequency of the radio frequency power supply is set to be 13.56MHz, and the input power range is 0-1000W, so that the reaction mixed gas is plasmatized and the reaction activity is enhanced.

In some embodiments, the first gas inlet 11 and the second gas inlet 12 of the gas mixer 10 are tangential inlet gases.

In some embodiments, the collector 50 is an electrostatic collector or a cyclone separator.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the present disclosure, the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" and the like mean that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.