CN108584882A - A kind of nano material preparation system and the technique using the system production nano material - Google Patents

Abstract

The invention discloses a nano material preparation system and a process for producing nano material by using the system. The system includes an atomization device for quantitative atomization of liquid precursors, a plasma reactor for generating powder nanomaterials, a nanopowder collection device for separating powder nanomaterials from the gas phase, and a tail gas treatment device for treating the separated gas phase device and intelligent control system. The process includes the following processes: (1) Precursor solution configuration; (2) Plasma excitation; (3) Precursor atomization; (4) Atomized liquid droplets are injected into plasma; (5) Collecting powder nano materials; (6) gas-liquid separation; (7) tail gas treatment. The preparation system and process of the present invention can be applied to various precursor substances suitable for atomization, and has the characteristics of wide application range; moreover, the system can continuously prepare and collect nanomaterials, with high production efficiency, simple process flow, and Controllable and highly automated.

Description

A nanomaterial preparation system and a process for producing nanomaterials using the system

technical field

The invention relates to the technical field of nanomaterial preparation, in particular to a nanomaterial preparation system and a process for producing nanomaterials using the system.

Background technique

Nanomaterials refer to materials whose size in at least one direction is less than 100nm, and can be divided into zero-dimensional nanomaterials, one-dimensional nanomaterials and two-dimensional nanomaterials according to their dimensions. Nanomaterials have significant surface effects, small size effects, macroscopic quantum tunneling effects, dielectric confinement effects, etc. These series of effects make nanomaterials exhibit special physical and chemical properties that are significantly different from macroscopic materials. These special properties make nanomaterials have extensive and important applications in the fields of energy, environment, functional new materials, medical treatment, and information technology. However, due to their small size and large specific surface area, the preparation of nanomaterials is difficult. At present, there are few methods and equipment systems that can produce nanomaterials in a large-scale, continuous and batch manner, which puzzles many nanomaterial experts and seriously restricts the development of nanotechnology.

According to the different properties of nanomaterials, there are many and complicated methods for synthesizing or preparing nanomaterials. Traditional nanomaterial preparation methods mainly include chemical methods and physical methods, among which the use of chemical methods is more common, and it can be divided into liquid-phase chemical precipitation and vapor-phase chemical deposition (CVD). Plasma Chemical Vapor Deposition (PCVD) is a very important branch of vapor phase chemical deposition. It uses plasma as a heating source for the preparation of nanomaterial precursors or as an excitation source for chemical reactions, so that the precursors are vaporized, cracked or reacted, and Condensation deposition on the substrate is especially suitable for the preparation of nano-film materials. However, the precursors used in the plasma chemical vapor deposition method are usually gaseous substances or substances that can be vaporized by plasma, which severely limits its application range. Moreover, the PCVD method is usually a batch production with low efficiency and is not suitable for the preparation and collection of powder materials.

Contents of the invention

The object of the present invention is to propose a nano-material preparation system with simple structure and high yield and a process for producing nano-materials by using the system to address the above-mentioned shortcomings of the prior art.

A nanomaterial preparation system of the present invention includes an atomization device for quantitatively atomizing liquid precursors, a plasma reactor for generating powder nanomaterials, a nanopowder collection device for separating powder nanomaterials from the gas phase, and A tail gas treatment device for processing the separated gas phase and an intelligent control system for regulating various reaction parameters and process parameters in the process of preparing nanomaterials from precursors.

Preferably, the plasma reactor includes a plasma generating device, a plasma reaction chamber and a condensation part.

Preferably, the plasma generating device is a DC plasma generator, a microwave plasma generator or an inductively coupled plasma generator.

Preferably, the plasma reaction chamber includes two coaxial socketed cylinders.

Preferably, the atomized liquid precursor is injected into the coaxially arranged plasma reaction chamber by a carrier gas in a normal direction.

Preferably, the atomization device is a high-pressure spray or an ultrasonic spray device.

Preferably, the nanopowder collection device 4 includes a gas-liquid separation device 50, a collection bottle 41, and a gas-solid separation device 45, and the gas-solid separation device 45 is a cyclone separator 40, a wet separator or a bag collector.

Preferably, the cooling method of the gas-liquid separation device is water cooling, air cooling or cooling liquid cooling.

Preferably, the tail gas treatment device includes a treatment tank filled with an absorption liquid; the absorption liquid is an acidic absorption liquid or an alkaline absorption liquid.

The process of producing nanomaterials using the above-mentioned system of the present invention includes the following processes: (1) Precursor solution configuration; (2) Plasma excitation; (3) Precursor atomization; (4) Atomized droplet normal direction Plasma injection; (5) collection of powder nanomaterials; (6) gas-liquid separation; (7) tail gas treatment.

A nanomaterial preparation system provided by the present invention and a process for producing nanomaterials using the system can be applied to various precursor substances suitable for atomization, and have the characteristics of a wide range of applications; moreover, the system can be continuously prepared and Collect various zero-dimensional, one-dimensional or two-dimensional inorganic nanomaterials, metal nanomaterials, nanometal oxides or sulfides, carbon nanomaterials and hybrid nanomaterials, with high production efficiency, simple process flow, controllable process, and automation It is a new type of powder nanomaterial preparation technology and system.

Description of drawings

Fig. 1 is a schematic diagram of a nanomaterial preparation system of the present invention;

Fig. 2 is a process flow diagram of the present invention.

1-plasma reactor; 10-plasma generator; 11-plasma power supply; 12-plasma gun; 13-plasma gun intake valve; 14-plasma working gas; 15-cooling medium; 16-plasma Front end of body gun; 17-plasma; 20-precursor atomization device; 21-peristaltic pump; 22-precursor; 23-atomizer; 24-spray chamber; 25-carrier gas pipeline solenoid valve; 27- Front end of atomization chamber; 30- Plasma reaction chamber; 31- External cavity of plasma reaction chamber; 32- Internal cavity of plasma reaction chamber; 321- Injection port; 34- Plasma auxiliary gas inlet ; 341-plasma auxiliary gas; 35-plasma auxiliary gas pipeline electromagnetic valve; 36-plasma reaction chamber inner cavity tail end; 3-condensing part; 37-cooling medium electromagnetic valve; 38-condensing pipe; Tail of the plasma reaction chamber; 4-nanometer powder collection device; 40-cyclone separator; 41-collection bottle; 42-the lower end of the cyclone separator; 43-the upper end of the cyclone separator; 44-the air inlet of the cyclone separator; 45 -gas-solid separation device; 50-gas-liquid separation device; 51-condenser; 52-cooling medium solenoid valve; 53-front end of gas-liquid separation device; 54-bottom of gas-liquid separation device; 55-gas-liquid separation device Bottom liquid outlet; 56-tail of gas-liquid separation device; 57-liquid phase collection bottle; 60-tail gas treatment device; 61-inlet pipe; 62-bottom of air inlet pipe; Bottom; 65-processing tank; 70-intelligent control system; 71, 72, 73, 74, 75-thermocouple; 81, 82, 83, 84, 85, 86-connecting flange.

Detailed ways

The following are specific embodiments of the present invention and in conjunction with the accompanying drawings, the technical solutions of the present invention are further described, but the present invention is not limited to these embodiments.

As shown in FIG. 1 , the nanomaterial preparation system of the present invention includes: a precursor atomization device 20 for quantitatively atomizing liquid precursors, a plasma reactor 1 for generating powder nanomaterials, and a powder nanomaterial and The nanopowder collection device 4 for gas phase separation, the tail gas treatment device 60 for treating the separated gas phase, and the intelligent control system 70 for regulating various reaction parameters and process parameters in the process of preparing nanomaterials from precursors.

The plasma reactor 1 may include a plasma generating device 10 , a plasma reaction chamber 30 and a condensation part 3 .

A plasma generating device 10 consisting of a plasma power source 11 and a plasma gun 12, a precursor atomization device 20, a cylindrical plasma reaction chamber outer chamber 31 and a plasma reaction chamber inner chamber 32 coaxial Horizontally arranged plasma reaction chamber 30, a cyclone separator 40, a gas-liquid separation device 50, a tail gas treatment device 60 and an intelligent control system 70; The plasma working gas 14 in the body gun 12 is excited, and forms a plasma 17 in the plasma reaction chamber 30 composed of two circular, coaxially arranged plasma reaction chamber outer chambers 31 and inner chambers 32, which Finally, the precursor 22 is quantitatively sent to the atomizer 23 through the peristaltic pump 21 for atomization, and the atomized droplets enter the atomization chamber 24 to form high-concentration precursor atomized droplets, and then the carrier gas 26 passes through The injection port 321 of the atomization chamber 24 connected to the plasma reaction inner cavity 32 injects the atomized liquid droplets of the precursor into the plasma 17 in the normal direction to make it react rapidly, wherein the carrier gas is controlled by the electromagnetic valve 25 of the carrier gas pipeline 26 flow rate, the product after the reaction is condensed into powder nanomaterials in the condensation part 3 of plasma reaction chamber tail 39, and powder nanomaterials are jointly formed by plasma working gas 14, plasma auxiliary gas 341 and carrier gas 26. It is sent into the cyclone separator 40, the plasma gun inlet valve 13 controls the entering amount of the plasma working gas 14, the powder nano material is collected in the collection bottle 41, and the gas phase part enters in the gas-liquid separation device 50, After being condensed by the condensation pipe 51 installed at the front end 53 of the gas-liquid separation device 50, the part with low boiling point is cooled into a liquid state and collected in the liquid phase collection bottle 57, and the remaining gas phase part is sent to the tail gas treatment device 60 for Remove polluting toxic gases. The intelligent control system 70 regulates the diameter and temperature of the plasma 17 by controlling the power of the plasma power supply 11, the switch and flow of the plasma working gas 14, and collecting the data of the thermocouple 71, and controls the electromagnetic flow rate of the carrier gas pipeline by collecting the speed data of the peristaltic pump 21 and controlling the temperature of the plasma 17. Valve switch, set the flow rate of the precursor 22 into the atomizer 23, make it quantitatively atomized, and control its speed into the plasma 17, so as to achieve the appropriate reaction conditions and reaction rate; The data of the thermocouples 72, 73, 74, 75 and the cooling medium solenoid valves 37, 52 controlling each cooling medium pipeline intelligently adjust and set the temperature of the condensation zone of the powder nanomaterial and the temperature of the gas-liquid separation.

The plasma generator 10 can be composed of a plasma power source 11 and a plasma gun 12 . The plasma power supply 11 can be a DC plasma power supply, a microwave plasma power supply or an inductively coupled plasma power supply.

The front end 16 of the plasma gun can extend into the cavity 32 of the plasma reaction chamber and be arranged coaxially with it. The tail end 18 of the plasma gun 12 is connected with the air intake pipeline of the plasma working gas 14 and the cooling medium 15 of the gun body. The pipeline, and the inlet pipeline of the plasma working gas 14 is connected with a solenoid valve, which can control its opening and flow rate, so as to adjust the diameter and temperature of the plasma 17. The cooling medium 15 is used to cool the parts of the gun body so as not to be damaged and affect the service life.

The precursor atomization device 20 may consist of a peristaltic pump 21 , an atomizer 23 and an atomization chamber 24 . The peristaltic pump 21 quantitatively sends the precursor 22 into the atomizer 23 for atomization, and the atomized tiny droplets enter the atomization chamber 24, the front end 27 of the atomization chamber is connected to the pipeline of the carrier gas 26, and the other end passes through The flange 81 is connected to the injection port 321 , and the atomized precursor is normally injected into the plasma by the carrier gas 26 to react. According to the number of injection ports 321 , the precursor atomization device 20 is matched with the corresponding connection.

The plasma reaction chamber 30 may include two coaxial socketed cylinders. In this embodiment, the plasma reaction chamber 30 is formed by coaxially nesting two cylindrical plasma reaction chamber outer chambers 31 and plasma reaction chamber inner chambers 32 of different sizes. The outer chamber body 31 and the inner chamber The body 32 can be made of high temperature resistant metal alloy, corundum, quartz or refractory bricks, and the outer cavity 31 is preferably made of refractory bricks to improve its thermal insulation efficiency. A plurality of symmetrically distributed injection ports 321 are opened in the inner cavity 32 near the front end 16 of the plasma gun along the radial direction of the cavity, and extend to the outside of the outer cavity 31 to connect with the precursor atomization device 20 . A plurality of auxiliary gas inlets 34 are distributed between the inner cavity body 32 and the outer cavity body 31 at one end connected to the plasma reaction chamber 30 and the plasma gun 12, and the switch and flow of the auxiliary gas 341 are electromagnetically controlled by the plasma auxiliary gas pipeline. The valve 35 is controlled to cool the inner cavity 32 to avoid its high-temperature damage, and at the same time, purge the powder nanomaterials and send them into the cyclone separator 40 . A thermocouple is installed near the injection port 321 and at the outlet of the tail end 36 of the inner cavity 32 to detect the plasma reaction temperature and the plasma outlet temperature. A condenser tube 38 is installed at the tail part 39 of the plasma reaction chamber. The cooling medium flows through the condenser tube 38 to reduce the temperature in the chamber. The temperature in the chamber is detected by a thermocouple 73. The purpose of reducing the temperature in the reaction chamber is to promote the reaction. The final product is condensed to form powder nanomaterials, while providing subsequent gas-liquid separation efficiency.

The nanopowder collection device 4 includes a gas-liquid separation device 50, a collection bottle 41, and a gas-solid separation device 45. The gas-solid separation device 45 can be a cyclone separator 40, a wet separator or a bag collector. In this embodiment, the gas-solid separation device 45 is a cyclone separator 40 .

The air inlet 44 of the cyclone separator 40 is coaxially connected with the plasma reaction chamber 30 through the flange 82, the lower end 42 of the cyclone separator is connected with the collection bottle 41 of powder nanomaterial through the flange 84, and the upper end 43 of the cyclone separator is connected with the gas The liquid separator 50 is connected by a flange 83 .

The front end 53 of the gas-liquid separation device 50 is connected with the cyclone separator 40 by a flange, and a thermocouple 74 is arranged at the front end 53 of the gas-liquid separation device 50 to detect the temperature of the gas phase part entering the gas-liquid separation device 50, and pass Adjust the cooling medium solenoid valve 52 of the condensation pipe 51 installed at the front end of the gas-liquid separation device, and detect the temperature of the gas phase after condensation by the thermocouple 75, control the switch of the cooling medium, and realize the condensation of low boiling point substances in the gas phase, and remove it from the gas phase and flow into the liquid phase collection bottle 57 connected to the bottom 54 liquid discharge port 55 of the gas-liquid separation device 50, the liquid discharge port 55 is connected with the liquid phase collection bottle 57 by a flange 85 to realize the separation of the low boiling point substance and the gas phase part separation.

The inlet pipe 61 of the tail gas treatment device 60 is connected to the tail portion 56 of the gas-liquid separation device 50 through a flange 86, the bottom end 62 of the inlet pipe 61 is immersed below the liquid level of the tail gas absorption liquid in the treatment tank 65, and the bottom end 64 of the exhaust port 63 above the liquid surface. Tail gas treatment devices can be connected in series in a similar manner, and the absorption liquid can be acidic absorption liquid, alkaline absorption liquid or a combination of the two, depending on the nature of the reaction product gas.

The intelligent control system 70 is equipped with a human-computer interaction interface, which controls the flow and opening of the working gas and liquid in each gas and liquid pipeline by collecting the temperature parameters of the thermocouples in each key area. Combined with specific algorithms, it can intelligently adjust the power of the plasma power supply, each Gas and liquid flow and opening, realize the continuous preparation of various nanomaterials.

As shown in Figure 2, the process of utilizing the above-mentioned system to produce powder nanomaterials of the present invention includes the configuration of precursor solution, plasma excitation, precursor atomization, atomized liquid droplets are injected into plasma, and powder nanomaterials are collected. , gas-liquid separation and tail gas treatment. First configure the precursor solution, then adjust the flow rate of the plasma working gas and auxiliary gas, turn on the plasma power supply, and excite the working gas to form a stable plasma. At the same time, the precursor solution is quantitatively atomized, and the atomized liquid droplets are injected into the plasma from the carrier gas to react, and the reacted products are condensed in the reaction chamber to form powder nanomaterials, and then the working gas, auxiliary gas and carrier gas The gas is sent to the gas-solid separation device to collect powder nanomaterials, the gas phase part is further cooled in the gas-liquid separation device to remove low boiling point substances and solvents, and the rest enters the tail gas absorption device to remove polluting toxic gases , Harmless gas discharge or recycling.

What is not involved above is applicable to the prior art.

Although some specific embodiments of the present invention have been described in detail by examples, those skilled in the art should understand that the above examples are only for illustration, rather than for limiting the scope of the present invention. Various modifications or additions or similar substitutions can be made to the described specific embodiments without departing from the direction of the present invention or exceeding the scope defined by the appended claims. Those skilled in the art should understand that any modifications, equivalent replacements, improvements, etc. made to the above implementations based on the technical essence of the present invention shall be included in the protection scope of the present invention.

Claims (10)

1. A nanomaterial preparation system, characterized in that it includes a precursor atomization device (20) for quantitatively atomizing liquid precursors, a plasma reactor (1) for generating powder nanomaterials, and a powder nanomaterial A nanopowder collection device (4) for separating from the gas phase, a tail gas treatment device (60) for treating the separated gas phase, and an intelligent control system (70) for regulating various reaction parameters and process parameters in the process of preparing nanomaterials from precursors . 2. A nanomaterial preparation system according to claim 1, characterized in that: the plasma reactor (1) includes a plasma generating device (10), a plasma reaction chamber (30) and a condensation part (3 ). 3. A nanomaterial preparation system according to claim 2, characterized in that: the plasma generator (10) is a DC plasma generator, a microwave plasma generator or an inductively coupled plasma generator. 4. A nanomaterial preparation system according to claim 2, characterized in that: the plasma reaction chamber (30) comprises two coaxial socketed cylinders. 5. A nanomaterial preparation system according to claim 4, characterized in that: the atomized liquid precursor is injected into the coaxially arranged plasma reaction chamber (30) in a normal direction by a carrier gas. 6. A nanomaterial preparation system according to claim 1, characterized in that: the precursor atomization device (20) is a high-pressure spray or ultrasonic spray device. 7. A nanomaterial preparation system according to claim 1, characterized in that: the nanopowder collection device (4) includes a gas-liquid separation device (50), a collection bottle (41), a gas-solid separation device (45) , the gas-solid separation device (45) is a cyclone separator (40), a wet separator or a bag collector. 8. The nanomaterial preparation system according to claim 7, characterized in that: the cooling method of the gas-liquid separation device (50) is water cooling, air cooling or cooling liquid cooling. 9. A nanomaterial preparation system according to claim 1, characterized in that: the tail gas treatment device (60) includes a treatment tank (65) filled with an absorption liquid; the absorption liquid is an acidic absorption liquid or an alkali absorbent liquid. 10. A process for producing nanomaterials using the system as claimed in claims 1-9, characterized in that it includes the following processes: (1) Precursor solution configuration; (2) Plasma excitation; (3) Precursor mist (4) Atomized liquid droplets are injected into the plasma; (5) Collecting powder nanomaterials; (6) Gas-liquid separation; (7) Tail gas treatment.