System and method for synthesizing nanoparticles through double-flame spray pyrolysis

Abstract

The invention relates to a system and a method for synthesizing nano-particles through double-flame spray pyrolysis. The system comprises a double-flame spray pyrolysis burner group (1), a visual flame reaction protection cover (2) and a nano-particle collection device (3), the double-flame spray pyrolysis burner group (1) is arranged in the visual flame reaction protective cover (2) and comprises two spray pyrolysis burners which are arranged at an included angle, the nano-particle collecting device (3) comprises a vacuum pipeline (31) and a particle filtering and collecting assembly (32) arranged on the vacuum pipeline (31), and the vacuum pipeline (31) is communicated with the visual flame reaction protective cover (2). Compared with the prior art, the problems that a single-flame system is uneven in temperature distribution and the reaction atmosphere cannot be accurately controlled can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of nanoparticle preparation, and in particular to a system and method for synthesizing nanoparticles by double flame spray pyrolysis. Background Art

[0002] Spray pyrolysis technology is an important method for synthesizing nanoparticles. It generates nanoparticles by atomizing liquid precursors and combining them with high-temperature combustion reactions. Flame spray pyrolysis relies on the temperature of the flame to drive the reaction. However, the temperature distribution of the flame is often uneven, which leads to non-uniform products. In addition, the reaction atmosphere (such as the proportion of oxygen, nitrogen, hydrogen, etc.) during the flame spray process will affect the morphology and composition of the product. However, since the atmosphere in a single flame environment is difficult to accurately control, the reaction process may be unstable, and the quality and morphology of the generated material may not be accurately controlled. Due to the excessively high local temperature of the flame or the uneven temperature distribution, the precursor material may be over-pyrolyzed, forming larger particles or particle aggregation, affecting the dispersibility and application performance of the nanoparticles. At the same time, the generated nanoparticles need to be effectively collected and post-processed, otherwise the products may adhere to the inside of the equipment, or there may be particle aggregation, affecting the purity and performance of the material.

[0003] Chinese patent CN112610953A describes a flame synthesis system for nanoparticles, which discloses that the system includes a burner, a visualized combustion chamber, and multiple dilution quenching devices. However, the system only uses a single flame to prepare nanoparticles, which cannot meet the requirements for regulating the temperature field and structural morphology of nanoparticles. Summary of the invention

[0004] The purpose of the present invention is to provide a dual-flame spray pyrolysis synthesis nanoparticle system and method to solve the problems of uneven temperature distribution and inability to accurately control the reaction atmosphere in a single flame system.

[0005] The object of the present invention can be achieved by the following technical scheme: a dual flame spray pyrolysis synthesis nanoparticle system, comprising a dual flame spray pyrolysis burner group, a visual flame reaction protection cover and a nanoparticle collection device;

[0006] The dual-flame spray pyrolysis burner group is arranged in a visual flame reaction protection cover, including two spray pyrolysis burners arranged at an angle, and the nanoparticle collection device includes a vacuum pipe and a particle filter collection assembly arranged on the vacuum pipe, and the vacuum pipe is connected to the visual flame reaction protection cover. The particle filter collection device is used to separate and collect particles from flue gas.

[0007] Preferably, the spray pyrolysis burner comprises a main body and a combustion gas inlet, a dispersion gas inlet, a protective gas inlet and a solution inlet opened on the main body;

[0008] The combustion gas inlet is connected to the combustion gas outlet through a combustion gas pipeline, the dispersion gas inlet is connected to the dispersion gas outlet through a dispersion gas pipeline, the protection gas inlet is connected to the protection gas outlet through a protection gas pipeline, and the solution inlet is connected to the solution outlet through a solution pipeline;

[0009] The combustion gas outlet, the protective gas outlet and the solution outlet are arranged on the upper end surface of the main body, and the dispersion gas outlet is connected to the solution outlet.

[0010] Further preferably, the main body is a rotating body structure, and the combustion gas inlet, the dispersion gas inlet and the protection gas inlet are arranged at intervals on the side of the main body along the axis direction of the main body.

[0011] More preferably, the protective gas inlet, the combustion gas inlet and the dispersion gas inlet are sequentially spaced apart along the axis direction of the main body.

[0012] More preferably, the protective gas outlet ring is arranged outside the combustion gas outlet, the combustion gas outlet ring is arranged outside the solution outlet, and the dispersion gas outlet is arranged in the main body and connected to the solution outlet.

[0013] Preferably, a metal foam structure is embedded in the combustion gas outlet and the protective gas outlet.

[0014] Preferably, nickel foam is embedded in the combustion gas outlet and the protective gas outlet.

[0015] In the present invention, each air inlet or liquid inlet of the two spray pyrolysis burners is connected to a corresponding air source or liquid source through a pipeline.

[0016] Further preferably, the spray pyrolysis burner also includes a support adjustment device for supporting and adjusting the height and angle of the main body.

[0017] Preferably, the visual flame reaction protection cover is a protection cover with a glass viewing window.

[0018] Preferably, the dual flame spray pyrolysis nanoparticle synthesis system further includes an igniter.

[0019] Further preferably, the igniter body is arranged outside the visual flame reaction protection cover, and the end thereof can extend into the visual flame reaction protection cover.

[0020] More preferably, the end of the igniter is retractable after providing a spark to avoid interfering with the flame.

[0021] In the present invention, one end of the spray pyrolysis burner provided with the gas outlet is inclined toward the other spray pyrolysis burner, that is, the bottoms of the two spray pyrolysis burners are far apart and the tops are close to each other.

[0022] Preferably, the two spray pyrolysis burners are symmetrically arranged at an angle.

[0023] Preferably, the two spray pyrolysis burners have the same structure.

[0024] Preferably, one end of the vacuum pipe is connected to the top outlet of the visualized flame reaction protection cover, and the other end is connected to the vacuum pump.

[0025] Further preferably, one end of the vacuum pipe connected to the top outlet of the visualized flame synthesis protection cover is provided with a closing structure.

[0026] Preferably, the dual-flame spray pyrolysis nanoparticle synthesis system further comprises a gas supply assembly for providing the dual-flame spray pyrolysis burner group with required gas.

[0027] Further preferably, the gas comprises combustion gas.

[0028] Still further preferably, the combustion gas comprises methane.

[0029] Further preferably, the gas comprises compressed air.

[0030] In the present invention, compressed air can be used as combustion gas and dispersion gas.

[0031] Further preferably, the gas includes a protective gas.

[0032] More preferably, the protective gas comprises nitrogen.

[0033] Further preferably, the gas supply assembly includes a gas cylinder, an air compressor and a gas flow meter, the gas cylinder and the air compressor are connected to the air inlet on the spray pyrolysis burner body through a pipeline, and a gas flow meter is provided on the pipeline.

[0034] More preferably, a flow regulating valve is provided on the pipeline, and the flow regulating valve is connected to the gas flow meter.

[0035] Preferably, the flow regulating valve and the gas flow meter are connected to the control component.

[0036] Further preferably, the control component includes a PLC controller.

[0037] Further preferably, the control component is connected to an air compressor.

[0038] Preferably, the dual-flame spray pyrolysis system for synthesizing nanoparticles further comprises a liquid supply component for providing the dual-flame spray pyrolysis burner group with the required metal salt or organic precursor solution.

[0039] Further preferably, the metal salt or organic precursor solution comprises an ethanol solution of cobalt nitrate and ferric nitrate, or an ethanol solution of ferric nitrate and tetrabutyl titanate.

[0040] Further preferably, the liquid feeding assembly comprises an injection pump, which is connected to a liquid inlet on the spray pyrolysis burner body and a metal salt or organic precursor solution storage tank through a pipeline.

[0041] More preferably, a liquid flow meter is provided on the pipeline.

[0042] Preferably, the injection pump and the liquid flow meter are connected to the control component.

[0043] Further preferably, the control component includes a PLC controller.

[0044] Preferably, the particle filter collection assembly is detachably mounted on the vacuum pipe.

[0045] In the present invention, the particle filtering and collecting component can separate, intercept and collect nanometer particles in the smoke.

[0046] Preferably, the particle filter collection assembly comprises a cyclone dust collector.

[0047] A method for synthesizing nanoparticles by double flame spray pyrolysis, using the above system, comprises the following steps:

[0048] S1: Adjust the height and angle of the two spray pyrolysis burners in the double flame spray pyrolysis burner group;

[0049] S2: a dual flame spray pyrolysis burner group produces nanoparticles by spray pyrolysis in a visualized flame reaction shield;

[0050] S3: Cooling and separating the collected nanoparticles through the vacuum line and particle filtration collection assembly of the nanoparticle collection device.

[0051] Preferably, after the collection is completed, the particle filter collection assembly is removed from the vacuum pipe to collect the nanoparticles.

[0052] In the present invention, the working principle of the double flame spray pyrolysis burner group is as follows:

[0053] More precise thermal control and reaction regulation are achieved by utilizing two independent combustion flames. Metal salts or organic precursor solutions are sprayed into the flame to form tiny droplets. These droplets evaporate rapidly and decompose to produce a pyrolysis reaction. The burner is usually composed of fuel gas and oxygen from the air to ensure flame stability and uniform temperature distribution. After the droplets enter the flame, due to the strong heat transfer, the solvent evaporates rapidly, and the precursor decomposes under high temperature conditions to produce metal oxides or other nanostructured materials. Due to the high temperature in the flame area and the rapid diffusion of the airflow, the products can condense into nanoscale particles in a very short time. Finally, the nanoparticles are quickly condensed and collected through the cooling process, usually collected at the flame outlet by sedimentation or airflow transmission. In the preparation of nanoparticles, the dual-flame burner optimizes the particle growth and condensation process by precisely controlling the relative position and flame intensity between the two flames. The ratio of fuel to oxidant, the combustion temperature, and the airflow rate can be optimized by adjusting the parameters of the two flames to meet the needs of specific material synthesis. In addition, the dual-flame system can effectively reduce the fluctuation of the cooling rate, avoid excessive condensation or sintering, and improve the morphological uniformity and dispersion of the particles. This structure not only improves the yield of particles, but also enables precise control of particle size, crystal form and surface properties.

[0054] Compared with the prior art, the present invention has the following beneficial effects:

[0055] 1. The present invention provides an integrated device for effectively recovering nanoparticles by means of double-flame spray pyrolysis, which prepares and efficiently recovers particles by double-flame spray pyrolysis technology.

[0056] 2. The present invention integrates dual-flame spray pyrolysis technology and nanoparticle deposition and recovery equipment. The dual-flame design achieves uniform distribution of the temperature field and improves the controllability of the particle morphology. At the same time, by optimizing the modular design of the equipment, the full process integration of nanoparticles from generation to recovery is achieved, which can be used for the efficient preparation and effective recovery of nanoparticles.

[0057] 3. The present invention provides an integrated dual-flame spray pyrolysis device, which achieves high efficiency and high quality in the preparation of nanoparticles, as well as high efficiency and environmental protection in the recycling process through innovative dual-flame design and modular integrated structure, and solves the problems of poor multi-component control performance during flame synthesis and difficult collection of flame synthesis in related technologies.

[0058] 4. The dual flames of the present invention work together to optimize temperature distribution and reaction atmosphere. By introducing a dual flame system, the equipment can set different temperatures and reaction atmospheres in the two flame areas, thereby achieving more precise temperature control and atmosphere regulation. This innovative design solves the problem of uneven temperature distribution and inability to accurately control the reaction atmosphere in a single flame system.

[0059] 5. The present invention adopts an adjustable spray system, which can adjust the spray particle size, spray volume and spray angle according to the characteristics of different precursor substances, ensure the uniform distribution of substances during the reaction process, and improve the reaction efficiency and the dispersibility of nanoparticles.

[0060] 6. The present invention is an integrated recovery system, which combines recovery technology to simultaneously recover unreacted precursor substances and by-products during the spray pyrolysis process, greatly improving the utilization efficiency of raw materials.

[0061] 7. The present invention has the advantages of high process flexibility, high recycling efficiency and environmental friendliness, and is widely applicable to the preparation of nano-oxides, metal particles and other functional materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a schematic diagram of the structure of the double flame spray pyrolysis synthesis nanoparticle system of the present invention;

[0063] Figure 2 Schematic diagram of support adjustment of the spray pyrolysis burner of the present invention Figure 1 ;

[0064] Figure 3 Schematic diagram of support adjustment of the spray pyrolysis burner of the present invention Figure 2 ;

[0065] Figure 4 It is a schematic diagram of the structure of the spray pyrolysis burner of the present invention;

[0066] Figure 5 A bottom view of the spray pyrolysis burner of the present invention;

[0067] Figure 6 A top view of the spray pyrolysis burner of the present invention;

[0068] Figure 7 for Figure 6 A cross-sectional view of

[0069] Figure 8 This is a schematic diagram of the internal structure of the spray pyrolysis burner of the present invention;

[0070] Fig. 9 This is a schematic diagram of the process of synthesizing nanoparticles by spray pyrolysis according to the present invention;

[0071] In the figure: 1-double flame spray pyrolysis burner group, 11-main body, 12-combustion gas inlet, 13-dispersion gas inlet, 14-protection gas inlet, 15-solution inlet, 16-combustion gas pipeline, 17-combustion gas outlet, 18-dispersion gas pipeline, 19-dispersion gas outlet, 110-protection gas pipeline, 111-protection gas outlet, 112-solution pipeline, 113-solution outlet, 114-fixed point, 115-support, 116-adjustment part, 2-visualized flame reaction protection cover, 21-igniter, 3-nanoparticle collection device, 31-vacuum pipeline, 32-particle filtering and collecting assembly, 33-vacuum pump, 4-gas supply assembly, 41-gas cylinder, 42-air compressor, 43-gas flow meter, 5-operating table, 6-injection pump. DETAILED DESCRIPTION

[0072] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0073] Example 1

[0074] A dual flame spray pyrolysis system for synthesizing nanoparticles, such as Figure 1 As shown, it includes a double flame spray pyrolysis burner group 1, a visualized flame reaction protection cover 2 and a nanoparticle collection device 3.

[0075] The double-flame spray pyrolysis burner 1 includes two spray pyrolysis burners arranged at an angle (i.e., non-parallel) in a visual reaction protection cover 2, and the nanoparticle collection device 3 includes a vacuum pipe 31 connected to the visual reaction protection cover 2 and a particle filter collection assembly 32 detachably mounted on the vacuum pipe 31, and the particle filter collection assembly 32 is used to separate and collect particles from flue gas.

[0076] Example 2

[0077] A dual flame spray pyrolysis system for synthesizing nanoparticles, such as Figures 2-3 As shown, the two spray pyrolysis burners both include a main body 11 and a support and adjustment device for supporting and adjusting the height and angle of the main body 11. In this embodiment, the support and adjustment device includes a support member 115 and an adjustment member 116. The adjustment member 116 is connected to a fixed point 114 at the bottom of the main body 11. The support member 115 is connected to the adjustment member 116 and the operating table 5. The height and angle of the two main bodies 11 can be adjusted by the cooperation of the adjustment member 116 and the support member 115, thereby achieving more precise temperature control. The rest is the same as in Example 1.

[0078] Example 3

[0079] A dual flame spray pyrolysis synthesis nanoparticle system, wherein a support member 115 and an adjusting member 116 are both provided with a connecting plate with a plurality of threaded holes distributed thereon, and the height and angle of a main body 11 and the distance between the two main bodies 11 can be adjusted by bolting the different threaded holes of the connecting plates on the support member 115 and the adjusting member 116.

[0080] As a further preferred solution, in this embodiment, the support member 115 can also be slidably arranged on the track of the operating table 5, and the distance between the two spray pyrolysis burners can be adjusted by adjusting and locking the positions of the support members 115 of the two spray pyrolysis burners on the track. The rest is the same as in Embodiment 2.

[0081] Example 4

[0082] A dual flame spray pyrolysis system for synthesizing nanoparticles, such as Figures 4 to 8 As shown, the spray pyrolysis burner includes a main body 11, a combustion gas inlet 12, a dispersion gas inlet 13, a protective gas inlet 14, a solution inlet 15, a combustion gas pipeline 16, a combustion gas outlet 17, a dispersion gas pipeline 18, a dispersion gas outlet 19, a protective gas pipeline 110, a protective gas outlet 111, a solution pipeline 112 and a solution outlet 113.

[0083] The main body 11 is a cylindrical structure, the combustion gas inlet 12, the dispersion gas inlet 13 and the shielding gas inlet 14 are provided on the side of the main body 11, and the solution inlet 15 is provided at the bottom center of the main body 11. Specifically, the combustion gas inlet 12 is connected to the combustion gas outlet 17 through the combustion gas pipeline 16 in the main body 11, the dispersion gas inlet 13 is connected to the dispersion gas outlet 19 through the dispersion gas pipeline 18 in the main body 11, the shielding gas inlet 14 is connected to the shielding gas outlet 111 through the shielding gas pipeline 110 in the main body 11, and the solution inlet 15 is connected to the solution outlet 113 through the solution pipeline 112 in the main body 11.

[0084] In this embodiment, the combustion gas outlet 17, the protective gas outlet 111 and the solution outlet 113 are arranged on the upper end surface of the main body 11, and the dispersion gas outlet 19 is arranged in the main body 11 and connected to the solution outlet 113. The liquid and the dispersion gas meet below the surface of the main body 11, so that the liquid is broken and rushes out of the surface, and the combustion gas is ignited on the surface of the main body 11. The rest is the same as that of Example 1.

[0085] Example 5

[0086] A dual flame spray pyrolysis synthesis nanoparticle system, in this embodiment, nickel foam is embedded at the combustion gas outlet 17 and the protective gas outlet 111, and the porosity of the nickel foam in this embodiment is 96%. In addition, in this embodiment, the protective gas inlet 14, the combustion gas inlet 12 and the dispersion gas inlet 13 are sequentially arranged from top to bottom along the axis direction of the main body 11, the protective gas outlet 111 is arranged outside the combustion gas outlet 17, and the combustion gas outlet 17 is arranged outside the solution outlet 113.

[0087] In this embodiment, the system further includes an air supply component 4 and a liquid supply component. The air supply component 4 includes a gas cylinder 41, an air compressor 42 and a gas flow meter 43, and the liquid supply component includes an injection pump 6. The protective gas inlet 114 is connected to the protective gas cylinder 41 through a pipeline, the combustion gas inlet 112 is connected to the combustion gas cylinder 41 through a pipeline, and the dispersion gas inlet 113 is connected to the air compressor 42 through a pipeline, and a gas flow meter 43 is provided on each pipeline. The solution inlet 115 is connected to the injection pump 6 through a pipeline.

[0088] In this embodiment, the double-flame spray pyrolysis burner group 1, the visual flame reaction protection cover 2 and the nanoparticle collection device 3 are all arranged on the operating table 5. The rest is the same as that of the embodiment 4.

[0089] Example 6

[0090] A dual flame spray pyrolysis synthesis nanoparticle system. In this embodiment, the combustion gas pipeline 16, the dispersion gas pipeline 18 and the protective gas pipeline 110 all include radial pipelines and axial pipelines. One end of the radial pipeline is connected to the air inlet, and the other end is connected to the axial pipeline through an air vent. A gas outlet is provided at the output end of the axial pipeline.

[0091] Furthermore, in this embodiment, an axial flow guide is also provided on the radial pipeline, which can make the gas more uniform and stable.

[0092] Example 7

[0093] A recycling device for effectively recovering nanoparticles by means of double flame spray pyrolysis, comprising:

[0094] An air supply unit (air supply assembly 4), which is used to supply the burner with the required compressed air and combustion gas;

[0095] Visual flame reaction protection cover 2, used to limit the products of flame synthesis burner in the pipeline and observe the situation after flame combustion;

[0096] A collecting device (nanoparticle collecting device 3); the collecting device includes a collecting piece connected to the visual flame reaction protection cover, the collecting part uses a vacuum pump to form a vacuum, and the collecting part is used to collect the post-combustion flame synthesis product;

[0097] The double flame burner (double flame spray pyrolysis burner group 1) is designed to realize symmetrical double flame burner placement, and the distance, height and angle between the burners are adjusted to realize the regulation of the composition and structure of the nanoparticles.

[0098] Optionally, the gas supply unit includes a gas cylinder, a gas line and an air compressor. The gas cylinder is placed in a gas cylinder cabinet, connected to the gas line and a flow meter, and a pressure gauge monitors the gas line pressure in real time. The air compressor supplies the required air and is connected to the burner using a gas flow meter.

[0099] Optionally, the visualized flame synthesis protective cover is a square protective cover with a glass viewing window, and the double-flame synthesis burner burns in the visualized flame synthesis protective cover.

[0100] Optionally, the collecting part includes a vacuum pipe, one end of which is connected to the top outlet of the visual flame synthesis protection cover, and the other end is connected to the particle filtering and collecting device; a vacuum pump, which is connected to the rear end pipe of the particle filtering and collecting device of the vacuum pipe, and a pressure gauge is provided on the vacuum pump to adjust the vacuum degree, so as to facilitate the control of the air flow velocity in the product recovery process.

[0101] Optionally, the double flame burner includes two burners with the same structure and four supporting devices. The burners with the same structure can achieve similar flame structures. The supporting device is arranged between the test bench and the burner to support the burner and adjust the combustion angle.

[0102] This embodiment also provides a method for adjusting the nanoparticles of flame synthesis products, which uses the collection device of the double flame spray pyrolysis products as described above to collect the products. Among them, a method for adjusting the nanoparticles of flame synthesis products includes adjusting the height of the double flame support angle piece and the angle fixed by the adjustment screw to control the flame combustion angle of the double flame; adjusting the flame height and flame width generated by the flame burner according to the adjustment of the gas flow rate of the air supply part to adjust the nanoparticles; adjusting the vacuum degree of the vacuum pump, controlling the vacuum degree in the pipeline to collect the synthesis products of the flame synthesis burner, and in the product collection part, using the path of the vacuum pipeline to cool the product; collecting the product after the vacuum degree is stable, stopping the vacuum pump after the combustion is completed, and collecting the nanoparticles collected by the particle filtering collection device.

[0103] Example 8

[0104] The existing technology has the following problems: (1) The single flame structure leads to uneven temperature distribution, which affects the uniformity and controllability of nanoparticles; (2) The recovery process of nanoparticles is inefficient, and some particles cannot be effectively collected, resulting in waste of resources; (3) The modularity of the device is low, making it difficult to achieve full process optimization from preparation to recovery. Therefore, there is an urgent need for an integrated device that can integrate spray pyrolysis and recovery functions to solve the above problems. Dual-flame spray pyrolysis is an important method for preparing nanoparticles with high yield, rapid reaction and low equipment requirements.

[0105] The present embodiment provides an integrated device for synthesizing nanoparticles by dual flame spray pyrolysis, including an air supply unit (air supply assembly 4), a visual flame reaction protection cover 2, a collection unit (nanoparticle collection device 3) and a dual flame burner (dual flame spray pyrolysis burner group 1).

[0106] Among them, the air supply part is used to supply the combustion gas and compressed air required by the burner.

[0107] Visual flame reaction shield, used to confine the flame spray pyrolysis burner combustion products can be concentrated in the pipe, and the flame state can be observed.

[0108] The collecting part includes a connector starting from the connection between the collecting part and the visual flame reaction protection cover, and a particle filtering and collecting device part. A vacuum environment is formed between the collecting part and the protection cover to collect flame combustion pyrolysis products.

[0109] The double flame burner is used to adjust the angle and distance of the burner, as well as the combustion atmosphere and temperature to regulate the nanoparticles.

[0110] Among them, the particle filtering and collecting device in the collecting part can use a cyclone dust collector, etc., which can be set according to actual conditions. The particle collector used in the following embodiments is used to collect and explain the product.

[0111] It is understandable that during the reaction process, the products formed by the dual flame spray pyrolysis are mixed with the high-temperature flue gas formed after the combustion of the combustion gas, thereby achieving the cooling of the high-temperature flue gas and the products in this embodiment, and utilizing a recovery path with controllable length so that the products can be fully cooled before reaching the particle filter collection device. The dual flame spray pyrolysis burner is completely wrapped in a visual flame reaction protective cover, and the combustion products are fully confined in the protective cover, thereby maximizing the recovery rate of the products. A vacuum is formed between the collection portion and the visual flame reaction protective cover, and the vacuum is utilized to accurately cause the products to fall into the particle filter collection device.

[0112] In this embodiment, the gas supply unit is a collection unit of a gas cylinder cabinet and an air compressor, which supplies the burner and air to the flame burner.

[0113] It is understandable that the gas supply unit of this embodiment includes a gas cylinder and an air compressor, a pressure gauge is used to control the pipeline pressure, and a gas flow meter is used to accurately control the flame combustion gas and air, so that the flame combustion can effectively control the height and width of the flame and achieve effective symmetry of the double flame.

[0114] In this embodiment, the visualized flame reaction protection cover is a square technical device with a visualized glass window, and the flame of the double-flame burner is completely burned in the visualized flame reaction protection cover.

[0115] It can be understood that the visual flame reaction protection cover of this embodiment is a square technical device with a visual glass window. The flame of the dual-flame burner is completely burned inside it, and the combustion products are completely confined in the pipeline. The particle filtering and collecting device is used to separate, intercept and collect the particles in the flue gas. The visual flame reaction protection cover isolates the flame from the outside air, preventing the outside air from entering the flame field during the reaction and affecting the reaction, and effectively prevents the particles after the reaction from diffusing into the air due to the air flow field and gravity, causing product loss, low recovery rate, and air pollution. The problem improves the effective recovery of the product. The device is equipped with a glass visualization window, which can observe the combustion of the dual flames during the combustion process, and whether the flow changes in the air supply section can be responded to in time. In addition, it is convenient to adjust the angle and height changes of the dual flames.

[0116] In an embodiment of the present application, the collecting part includes: a vacuum pipe, one end of which is connected to the top outlet of the visual flame synthesis protective cover, and the other end is connected to the particle filtering and collecting device; a vacuum pump, which is connected to the rear end pipe of the particle filtering and collecting device of the vacuum pipe, and a pressure gauge is provided on the vacuum pump to adjust the vacuum degree, so as to facilitate the control of the air flow velocity in the product recovery process.

[0117] It is understood that the vacuum pipe cools the products and high-temperature flue gas after the reaction and is a channel for recovering the products. Different vacuum degrees of the vacuum pump will produce different recovery air flow velocities.

[0118] In this embodiment, the collecting part further includes: a particle filtering and collecting device.

[0119] It is understandable that the collection part may also include a particle filter collection device, that is, a particle filter collection device may also be provided in this embodiment to separate and collect particles from the flue gas. Since there are sufficient cooling paths in the vacuum pipe, in this case, after the particle filter collection device is installed, it is ensured that it will not be affected by the high-temperature flue gas.

[0120] In this embodiment, the double flame burner includes: two burners with the same structure, a protective gas inlet, a dispersion gas inlet, a combustion gas inlet arranged on both sides of the burner, and a liquid feed port located at the lower end of the burner, and supporting parts.

[0121] It is understandable that in this embodiment, a support part can be arranged below the burner, and a fixing screw can be arranged outside the burner to adjust the height and angle of the burner, and the liquid feed hose can ensure the safe injection of liquid. A metal foam structure can be placed to achieve uniformity of the flame surface.

[0122] Among them, the metal foam is embedded in the burner, between the upper surface and the groove at the gas outlet; the use of metal foam can make the flame surface burn evenly and stably. The metal foam can be nickel-based, etc., and there is no clear limitation on this. The following embodiments use nickel-based metal foam as an example for explanation.

[0123] It is understandable that the present embodiment can be supported and adjusted with a supporting device. Adjustment member 116 is a connector responsible for connecting the burner and the bottom support (support member 115), which mainly plays the role of adjusting the burner angle, and the surface is evenly distributed with M6 threaded holes. Support member 115 is responsible for connecting adjustment member 116 and platform (operating platform 5), plays the role of being fixed on a stable experimental platform, and is responsible for fixing the horizontal distance between the two burners, and the same evenly distributed M6 threaded holes. On the basis of meeting the different requirements of nanoparticle preparation requirements, cost saving and simple adjustment.

[0124] Specifically, the specific structure of the burner in this embodiment includes a protective gas inlet, a dispersion gas inlet, a combustion gas inlet, and a liquid feed port at the lower end of the burner, and supporting parts. In this embodiment, all air inlet diameters are of uniform size, and a common gas quick valve is used as a connection, which is convenient for the equipment to change the gas path in the process of adjusting the distance and angle, and avoid the danger to the gas path caused by changing the position of the burner. In the burner, all air inlet paths are separate paths, and all paths do not affect each other. Among them, the liquid feed pipe diameter is a separate pipe diameter, which is connected to the soft rubber hose through a metal valve at the bottom. A hose connection is used to connect the liquid feed pipe and the injection pump, which is convenient for timely movement with the burner while changing the position.

[0125] In this embodiment, the dual flame burner also includes dual air intake paths, including multiple one-to-many conversion joints, which are directly connected to the quick interfaces on both sides of the burner to facilitate better mixing of combustion gas and compressed air. In addition, this embodiment does not require an external atomizing nozzle, and can directly achieve effective crushing and atomization of the liquid at the moment of passing through the upper surface of the burner through the internal structure design of the burner, and achieve condensation and growth in the process of passing through the combustion field.

[0126] In summary, according to the integrated device for synthesizing nanoparticles by dual flame spray pyrolysis proposed in the embodiment, the particle size and morphology of nanoparticles can be controlled by utilizing dual flames; a visual flame synthesis protective cover is used to isolate the flame spray pyrolysis products from the surrounding environment, thereby reducing the loss of flame spray pyrolysis products; the use of a collecting part can increase the cooling path of the nanoparticles and improve the collection rate of flame pyrolysis products; and the use of a vacuum pipeline can ensure that the particles pass through the particle filtration and collection device with the surrounding fluid and are effectively blocked at the particle filtration and collection device, thereby improving the working efficiency of the vacuum pump and the collection rate of the flame spray pyrolysis products.

[0127] Fig. 9 The schematic diagram of the process of an integrated device for synthesizing nanoparticles by dual flame spray pyrolysis provided in this embodiment. The integrated device for synthesizing nanoparticles by dual flame spray pyrolysis utilizes all the above-mentioned devices to perform the process of preparing nanoparticles by flame spray pyrolysis and collecting nanoparticles, wherein the method comprises the following steps:

[0128] In step S1 , the angle and height of the dual-flame burner, as well as the distance between the two burners are adjusted according to the desired design.

[0129] It is understandable that the present embodiment can adjust the distance, height and angle parameters to facilitate the subsequent control of the composition and structure of the nanoparticles.

[0130] In step S2, the air flow velocity and liquid velocity are adjusted according to the requirements of the nanoparticles, the height of the vacuum pipeline between the visual flame reaction protection cover and the particle filter collection assembly is adjusted, and the vacuum degree of the vacuum pump is designed to collect the flame pyrolysis products.

[0131] It is understandable that the present embodiment can change the parameters of the combustion reaction, achieve ultimate control over the nanoparticles through the combustion process, avoid impurities and environmental pollution caused by combustion, and improve the purity of the final product.

[0132] In step S3, when the feed amount reaches the expected design, the flame combustion is stopped and the product is collected by a particle filtering and recovery device.

[0133] It is understandable that, in this embodiment, after the injection process is completed, the particle recovery device can be removed in time and the final product can be collected. At this time, the combustion flame and the injection can be terminated.

[0134] According to the integrated device for synthesizing nanoparticles by dual flame spray pyrolysis proposed in this embodiment, nanoparticles with multiple components can be prepared under simple operation, and the structure can be designed according to requirements, such as core-shell structure, etc. At the same time, the cooling path required by the nanoparticles is realized by using a vacuum pipe, simplifying the integrated device.

[0135] In the prior art, the single flame structure leads to uneven temperature distribution, which affects the uniformity and controllability of nanoparticles, as well as the inefficiency of the recovery link of nanoparticles. Some particles cannot be effectively collected, resulting in difficulties such as waste of resources. In addition, the modularity of the device is low, making it difficult to achieve full process optimization from preparation to recovery. The double flame spray pyrolysis method of this embodiment is an efficient means of preparing nanoparticles. It uses two overlapping flames to provide a uniform and high-temperature reaction environment to quickly evaporate, decompose and form nanoparticles from the sprayed liquid precursor. This method can achieve precise control of the temperature field and reaction rate by adjusting the flame angle and height. Double flame spray pyrolysis can accurately control the particle size, cleanliness and purity of multi-component nanoparticles, quickly synthesize nanoparticles, and is suitable for preparing high-performance materials such as metal oxides, metal nanoparticles and composite materials.

[0136] The present invention can control the composition and structure of the product by adjusting the height and angle of the double flame burner; reduce the loss of flame synthesis particle products by using a visual flame synthesis protective cover, and control the flame by visually adjusting the flame height; and improve the collection efficiency of the double flame synthesis particle products by using a collecting part.

[0137] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A dual flame spray pyrolysis synthesis nanoparticle system, characterized in that: It comprises a double flame spray pyrolysis burner group (1), a visual flame reaction protection cover (2) and a nanoparticle collection device (3); The dual-flame spray pyrolysis burner group (1) is arranged in a visual flame reaction protection cover (2), and comprises two spray pyrolysis burners arranged at an angle. The nanoparticle collection device (3) comprises a vacuum pipe (31) and a particle filtering collection assembly (32) arranged on the vacuum pipe (31), and the vacuum pipe (31) is connected to the visual flame reaction protection cover (2).

2. The dual flame spray pyrolysis synthesis nanoparticle system according to claim 1, characterized in that: The spray pyrolysis burner comprises a main body (11) and a combustion gas inlet (12), a dispersion gas inlet (13), a protective gas inlet (14) and a solution inlet (15) which are arranged on the main body (11); The combustion gas inlet (12) is connected to the combustion gas outlet (17) via a combustion gas pipeline (16), the dispersion gas inlet (13) is connected to the dispersion gas outlet (19) via a dispersion gas pipeline (18), the protection gas inlet (14) is connected to the protection gas outlet (111) via a protection gas pipeline (110), and the solution inlet (15) is connected to the solution outlet (113) via a solution pipeline (112); The combustion gas outlet (17), the protective gas outlet (111) and the solution outlet (113) are arranged on the upper end surface of the main body (11), and the dispersion gas outlet (19) is connected to the solution outlet (113).

3. The dual flame spray pyrolysis synthesis nanoparticle system according to claim 2, characterized in that: The main body (11) is a rotating body structure, and the combustion gas inlet (12), the dispersion gas inlet (13) and the protection gas inlet (14) are arranged at intervals on the side of the main body (11) along the axial direction of the main body (11).

4. The dual flame spray pyrolysis synthesis nanoparticle system according to claim 3, characterized in that: The protective gas inlet (14), the combustion gas inlet (12) and the dispersion gas inlet (13) are arranged in sequence and at intervals along the axial direction of the main body (11); The protective gas outlet (111) is arranged outside the combustion gas outlet (17), the combustion gas outlet (17) is arranged outside the solution outlet (113), and the dispersion gas outlet (19) is arranged in the main body (11) and connected to the solution outlet (113).

5. The dual flame spray pyrolysis synthesis nanoparticle system according to claim 2, characterized in that: The spray pyrolysis burner also includes a support and adjustment device for supporting and adjusting the height and angle of the main body (11).

6. The dual flame spray pyrolysis synthesis nanoparticle system according to claim 1, characterized in that: The visual flame reaction protection cover (2) is a protection cover with a glass viewing window, and an igniter (21) is contained in the cover.

7. The dual flame spray pyrolysis synthesis nanoparticle system according to claim 1, characterized in that: One end of the vacuum pipe (31) is connected to the top outlet of the visualized flame reaction protection cover (2), and the other end is connected to the vacuum pump (33). The end of the vacuum pipe (31) connected to the top outlet of the visualized flame synthesis protection cover (2) is provided with a closing structure.

8. The dual flame spray pyrolysis synthesis nanoparticle system according to claim 1, characterized in that: It also includes a gas supply component (4) for providing the double flame spray pyrolysis burner group (1) with the required gas and a liquid supply component for providing the double flame spray pyrolysis burner group (1) with the required metal salt or organic precursor solution.

9. The dual flame spray pyrolysis synthesis nanoparticle system according to claim 8, characterized in that: The gas supply assembly (4) comprises a gas cylinder (41), an air compressor (42) and a gas flow meter (43); the gas cylinder (41) and the air compressor (42) are connected to the air inlet of the spray pyrolysis burner through a pipeline, and the gas flow meter (43) is provided on the pipeline.

10. A method for synthesizing nanoparticles by double flame spray pyrolysis, characterized in that: Using the system according to any one of claims 1 to 9, The following steps are involved: S1: Adjust the height and angle of the two spray pyrolysis burners in the double flame spray pyrolysis burner group (1); S2: A dual flame spray pyrolysis burner group (1) produces nanoparticles by spray pyrolysis in a visible flame reaction protection cover (2); S3: Cooling and separating the collected nanoparticles through the vacuum pipe (31) and the particle filtration collection assembly (32) of the nanoparticle collection device (3).

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