Circulation reactor for producing lithium difluoro (oxalato) borate

Abstract

The invention relates to the technical field of lithium difluoro (oxalato) borate preparation equipment, and discloses a circulating reactor for producing lithium difluoro (oxalato) borate, which comprises a material storage unit, a material mixing unit, a reactor body, an auxiliary recovery unit and a vacuum concentration tower, wherein the material storage unit is used for storing a plurality of solid or liquid reaction raw materials, the material mixing unit is used for mixing the plurality of reaction raw materials stored in the material storage unit, the reactor body is used for carrying out chemical reaction on the plurality of reaction raw materials, and the assistant recovery unit is used for recovering the reaction raw materials; the vacuum concentration tower is used for concentrating a product obtained after the reaction of the reactor body. According to the invention, recycling of the auxiliary agent is realized, environmental pollution is reduced, product quality is improved, intermediate links are reduced, the service life is long, the auxiliary agent of the system is recycled, the utilization rate is high, the cost is greatly reduced, no waste gas is generated, and the production equipment belongs to novel environment-friendly and energy-saving production equipment.

Description

Technical Field

[0001] The invention relates to the technical field of lithium difluorooxalate borate preparation equipment, in particular to a circulation reactor for producing lithium difluorooxalate borate. Background Art

[0002] Lithium-ion batteries are one of the most promising energy storage technologies. Lithium salt-based electrolytes are an indispensable and important component of lithium-ion batteries. Lithium difluorooxalate borate (LiODFB) is a chemical with excellent high and low temperature performance, wide operating temperature range and good thermal stability. It is regarded as the most promising electrolyte salt to replace LiPF6. Lithium difluorooxalate borate is mainly used in lithium battery electrolytes as a film-forming additive or conductive salt to improve the battery's cycle efficiency and capacity retention rate.

[0003] There are currently two methods for developing and synthesizing lithium difluorooxalatoborate, both of which have certain technical defects: 1. Lithium difluorooxalatoborate is generated by the reaction of lithium oxalate and boron trifluoride complexes. However, a large amount of lithium tetrafluoroborate is produced as a by-product in this process. Currently, it is mainly purified by recrystallization. However, no single solvent can separate lithium difluorooxalatoborate from lithium tetrafluoroborate. In addition, the yield of lithium difluorooxalatoborate is low through recrystallization, and the industrial production cost is high.

[0004] 2. Lithium oxalate and boron trifluoride complexes are reacted to generate lithium difluorooxalatoborate and lithium tetrafluoroborate, and then oxalic acid is added to the reaction system, followed by silicon tetrachloride dropwise added. Lithium tetrafluoroborate is converted into lithium difluorooxalatoborate by reacting with oxalic acid and silicon tetrafluoride. The reaction will produce a large amount of silicon tetrafluoride and hydrogen chloride waste gas, which will cause certain corrosion to the equipment, and it is easy to block the pipeline after reacting with the alkaline solution of tail gas treatment, causing safety hazards.

[0005] Although the process has been continuously improved in recent years, the reaction of lithium fluoride and boron trifluoride to form lithium tetrafluoroborate, and then adding oxalic acid and silicon tetrafluoride to the system to finally form lithium difluorooxalatoborate, still cannot solve the problem of generating a large amount of silicon tetrafluoride and hydrogen chloride waste gas. Due to many uncertainties and uncontrollable factors, the production operation is unstable, the product quality fluctuates greatly, and there are serious environmental problems and problems of waste of resources and high energy consumption.

[0006] Therefore, there is an urgent need in the art to improve the lithium difluorooxalate borate reactor to address the deficiencies of the prior art. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention provides a circulating reactor for the production of lithium difluorooxalate borate. In the present invention, the recycling of auxiliary agents is achieved, environmental pollution is reduced, product quality is improved, intermediate links are reduced, the service life is long, the system auxiliary agents are recycled, the utilization rate is high, the cost is greatly reduced, and no waste gas is generated. It is a new type of environmentally friendly and energy-saving production equipment.

[0008] To achieve the above object, the present invention provides the following technical solution: a circulating reactor for producing lithium difluorooxalate borate, comprising: a material storage unit, a material mixing unit, a reactor body, an auxiliary agent recovery unit and a vacuum concentration tower; The material storage unit is used to store several kinds of solid or liquid reaction raw materials, the mixing unit is used to mix the several kinds of reaction raw materials stored in the material storage unit, the reactor body is used to carry out chemical reactions on the several kinds of reaction raw materials, the auxiliary agent recovery unit is used to recover the reaction raw materials, and the vacuum concentration tower is used to concentrate the products after the reaction of the reactor body; The reactor body comprises a shell, a plurality of micro-channels are elastically connected inside the shell, a fixing ring for fixing the micro-channels is arranged inside the reactor body, a driving motor is arranged inside the reactor body, a rotating shaft concentric with the fixing ring is fixedly mounted on the output end of the driving motor, a plurality of raised blocks are fixedly connected to the inner side wall of the fixing ring, and a cam adapted to the raised blocks is fixedly connected to the side surface of the rotating shaft.

[0009] Preferably, a plurality of annular feed pipes connected to the outside are provided in the shell, and elastic tubes are installed at both upper and lower ends of the plurality of micro-channels, the elastic tubes are elastic and have electrically controlled solenoid valves inside, and connecting pipes are provided between the plurality of micro-channels, and the connecting pipes are connected to the annular feed pipe.

[0010] Preferably, an upper sealing plate and a lower sealing plate are respectively sealed and installed in the upper and lower parts of the shell, several of the elastic tubes penetrate the upper sealing plate and the lower sealing plate, the rotating shaft penetrates the upper sealing plate and the lower sealing plate, and a discharge bin is fixedly installed on the lower surface of the lower sealing plate, and the discharge bin is connected to the vacuum concentration tower.

[0011] Preferably, a plurality of heating rods are installed between the two fixing rings, and the upper sealing plate and the lower sealing plate are filled with heat exchange medium.

[0012] Preferably, blades are fixedly mounted on the side of the rotating shaft, and the blades are in two groups and are respectively located on the back sides of two fixing rings.

[0013] Preferably, a sleeve is fixedly mounted on the side of the rotating shaft, and a material conveying auger is fixedly mounted on the side of the rotating shaft. The material conveying auger is located in the sleeve and is adapted to the sleeve.

[0014] Preferably, the material storage unit includes a boron trifluoride storage device for storing boron trifluoride, a lithium fluoride storage device for storing lithium fluoride, a dimethyl carbonate storage device for storing dimethyl carbonate, an oxalic acid storage device for storing oxalic acid, an auxiliary agent storage device for storing auxiliary agents, and an alkali solution storage device for storing alkali solution.

[0015] Preferably, the mixing unit comprises a first-stage mixing device and a second-stage mixing device located between the storage unit and the reactor body, the first-stage mixing device is used to mix the raw materials in the lithium fluoride storage device and the dimethyl carbonate storage device, and the second-stage mixing device is used to mix the raw materials in the dimethyl carbonate storage device and the oxalic acid storage device. The raw materials mixed by the mixing unit are all transported to the reactor body, and the boron trifluoride storage device and the auxiliary agent storage device directly supply materials to the reactor body.

[0016] Preferably, the additive recovery unit comprises a waste gas absorption reactor and an additive recovery tower, the upper end of the waste gas absorption reactor is connected to the upper end of the reactor body, the additive recovery tower is connected to the additive storage device, and the alkali solution storage device is connected to the waste gas absorption reactor.

[0017] Preferably, a plurality of guide posts are fixedly mounted on the inner wall of the shell, a guide groove adapted to the guide posts is opened on the side of the fixing ring, two bearings are sleeved on the side of each guide post, and a spring sleeved on the side of the guide post is provided between the two bearings.

[0018] In view of the deficiencies of the prior art, the present invention provides a circulating reactor for producing lithium difluorooxalate borate, which overcomes the deficiencies of the prior art. The beneficial effects of the present invention are: 1. In the present invention, the efficiency of preparing lithium difluorooxalate borate is improved, and at the same time, the recycling of auxiliary agents is realized, environmental pollution is reduced, product quality is improved, and intermediate links are reduced. In the equipment system, hexamethyldisiloxane, hexamethyldisilazane or tetramethyldisiloxane is used as an auxiliary agent in the production process, and a recovery section is designed to effectively solve the problem of traditional silicon tetrachloride auxiliary agents producing silicon tetrafluoride and hydrogen fluoride, so that the auxiliary agent can be recovered and put into reproduction, the consumption of the auxiliary agent is greatly reduced, and the problem of corrosion equipment and pipeline blockage during tail gas treatment during production and operation is solved. The whole production process is continuous and smooth, the key equipment has stable performance and long service life, the system auxiliary agent is recycled, the utilization rate is high, the cost is greatly reduced, and no waste gas is generated, which belongs to a new environmentally friendly and energy-saving production equipment.

[0019] 2. In the present invention, when the reaction process is in the reactor body, the driving motor is started, the output end of the driving motor drives the rotating shaft to rotate, the rotating shaft drives the cam to rotate, a plurality of micro-channels are elastically connected in the reactor body, and the plurality of micro-channels are limited by fixed rings. When the raised position of the cam passes through the raised block, a thrust is generated on the raised block, thereby causing the micro-channel to shake, thereby accelerating the reaction time between the lithium fluoride solution, boron trifluoride gas, oxalic acid, alkali solution, auxiliary agent or dimethyl carbonate and other solvents in the micro-channel, thereby improving the efficiency of preparing lithium difluorooxalatoborate.

[0020] 3. In the present invention, a heatable medium is filled between the upper sealing plate and the lower sealing plate, and the heatable medium can be heated by turning on the heating rod. At the same time, the cam and the protruding block are used to drive the heating rod to stir the heat exchange medium between the upper sealing plate and the lower sealing plate when the fixed ring shakes, thereby improving the heating efficiency of the heat exchange medium and the heat exchange efficiency between the heat exchange medium and the micro-channel.

[0021] 4. In the present invention, when the driving motor drives the rotating shaft to rotate, the rotating shaft drives the feeding auger to rotate, and the feeding auger transports the heat exchange medium located in the lower part of the reactor body to the upper part of the reactor body, thereby improving the heat exchange rate of the heat exchange medium in the reactor body.

[0022] 5. In the present invention, when it is necessary to add reaction raw materials into the micro-channel or discharge the reaction products, the drive motor is turned on, the output end of the drive motor drives the rotating shaft to rotate, and the rotating shaft drives the blades to rotate, thereby accelerating the efficiency of the reaction raw materials entering the micro-channel or the reactants discharging from the micro-channel.

[0023] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0025] Figure 1 It is a schematic structural diagram of the overall reaction system of the present invention; Figure 2 It is a structural schematic diagram of another side view of the overall reaction system of the present invention; Figure 3 It is a structural schematic diagram of a partial cross-section of the shell in the present invention; Figure 4 It is a schematic structural diagram of a cross-section of the casing in the present invention; Figure 5 It is a structural schematic diagram of the annular feed pipe in the present invention; Figure 6 It is a structural schematic diagram of the heating rod in the present invention; Figure 7 It is a schematic diagram of the structure of the elastic tube in the present invention; Figure 8 It is a structural schematic diagram of the discharge bin in the present invention; Fig. 9 for Figure 5 The enlarged structural diagram at A in the middle; Fig.10 for Figure 7 The enlarged structural diagram at B in the middle; Fig.11 for Figure 8 The enlarged structural diagram at C in the middle; Fig.12 It is a block diagram of the reaction system of the present invention.

[0026] In the figure: 1, storage unit; 2, mixing unit; 3, reactor body; 4, additive recovery unit; 5, vacuum concentration tower; 6, shell; 7, micro-channel; 8, fixed ring; 9, drive motor; 10, rotating shaft; 11, raised block; 12, cam; 13, annular feed pipe; 14, elastic tube; 15, connecting pipe; 16, upper sealing plate; 17, lower sealing plate; 18, discharge bin; 19, heating rod; 20, paddle ; 21. Casing; 22. Feeding auger; 23. Boron trifluoride storage device; 24. Lithium fluoride storage device; 25. Dimethyl carbonate storage device; 26. Oxalic acid storage device; 27. Auxiliary agent storage device; 28. Alkali solution storage device; 29. ​​First-stage mixing device; 30. Second-stage mixing device; 31. Waste gas absorption reactor; 32. Auxiliary agent recovery tower; 33. Spring; 34. Guide groove; 35. Guide column; 36. Bearing. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] See also Figure 1-Figure 12, a circulating reactor for the production of lithium difluorooxalate borate, comprising: a storage unit 1, a mixing unit 2, a reactor body 3, an auxiliary agent recovery unit 4 and a vacuum concentration tower 5; wherein the storage unit 1 is used to store several kinds of solid or liquid reaction raw materials, the mixing unit 2 is used to mix several kinds of reaction raw materials stored in the storage unit 1, the reactor body 3 is used to chemically react several kinds of reaction raw materials, the auxiliary agent recovery unit 4 is used to recover the reaction raw materials, and the vacuum concentration tower 5 is used to concentrate the products after the reaction of the reactor body 3; the reactor body 3 comprises a shell 6, a plurality of micro-channels 7 are elastically connected in the shell 6, a fixing ring 8 for fixing the micro-channels 7 is provided in the reactor body 3, a driving motor 9 is provided in the reactor body 3, a rotating shaft 10 concentric with the fixing ring 8 is fixedly installed at the output end of the driving motor 9, a plurality of protrusions 11 are fixedly connected to the inner side wall of the fixing ring 8, a cam 12 adapted to the protrusions 11 is fixedly connected to the side of the rotating shaft 10, the storage unit 1 comprises a boron trifluoride storage device 23 for storing boron trifluoride, a boron trifluoride storage device 23 for storing boron trifluoride The mixing unit 2 includes a first-stage mixing device 29 and a second-stage mixing device 30 located between the storage unit 1 and the reactor body 3. The first-stage mixing device 29 is used to mix the raw materials in the lithium fluoride storage device 24 and the dimethyl carbonate storage device 25. The second-stage mixing device 30 is used to mix the raw materials in the lithium fluoride storage device 24 and the dimethyl carbonate storage device 25. The raw materials in the dimethyl carbonate storage device 25 and the oxalic acid storage device 26 are mixed, and the raw materials mixed by the mixing unit 2 are transported to the reactor body 3. The boron trifluoride storage device 23 and the auxiliary agent storage device 27 directly feed into the reactor body 3. The auxiliary agent recovery unit 4 includes a waste gas absorption reactor 31 and an auxiliary agent recovery tower 32. The upper end of the waste gas absorption reactor 31 is connected to the upper end of the reactor body 3, the auxiliary agent recovery tower 32 is connected to the auxiliary agent storage device 27, and the alkali solution storage device 28 is connected to the waste gas absorption reactor 31.

[0029] Specifically, the preparation of lithium difluorooxalate borate includes the following steps: (1): lithium fluoride solution, boron trifluoride gas, oxalic acid, alkali solution, auxiliary agent (including but not limited to hexamethyldisilazane, hexamethyldisiloxane, heptamethyltrisiloxane, etc.) and dimethyl carbonate solvent are respectively introduced into the lithium fluoride storage device 24, the boron trifluoride storage device 23, the oxalic acid storage device 26, the alkali solution storage device 28, the auxiliary agent storage device 27 and the dimethyl carbonate storage device 25 for storage; (2): Lithium fluoride and dimethyl carbonate solvent are pumped into a mixing device 29, the temperature is maintained at 15°C, and the mixture is stirred evenly. The mixed lithium fluoride and dimethyl carbonate solvent is pumped into the reactor body 3; (3): After boron trifluoride is pumped into the reactor body 3, the reaction is carried out at room temperature for 6 hours; (4): After the above steps are completed, oxalic acid and dimethyl carbonate are pumped into the second-stage mixing device 30, stirred evenly and then pumped into the reactor body 3, the temperature is raised to 60°C, and the reaction is carried out for 2-4 hours; (5): After the above steps are completed, one or more auxiliary agents (hexamethyldisilazane, hexamethyldisiloxane, heptamethyltrisiloxane, etc.) are pumped into the reactor body 3 for reaction for 4-8 hours; (6): After the reaction in the reactor body 3 is completed, the reactor body 3 is evacuated to negative pressure through the waste gas absorption reactor 31 by a vacuum pump, and the temperature is increased by the vacuum concentration tower 5 for degassing and concentration, and the temperature is controlled at about 60°C. About 40% of the dimethyl carbonate is removed and recovered through the condenser. The remaining gas is treated by the tail gas treatment device and returned to the auxiliary agent storage device 27 for storage; then the temperature is reduced and crystallized, and the temperature is controlled at about 10°C to obtain a lithium difluorooxalate borate filtrate. The crystallized solution is filtered through a two-in-one filter press to obtain a crude lithium difluorooxalate borate. The dimethyl carbonate filtrate after filtration is transferred to a solvent recovery tank for recovery; the semi-finished crude lithium difluorooxalate borate is placed in a vacuum dryer at a temperature of 130°C and vacuum dried at absolute negative pressure for 10 hours to obtain a finished lithium difluorooxalate borate. The organic gas is first deeply condensed and recovered, and the remaining gas enters the tail gas treatment device for concentration by activated carbon adsorption, and is desorbed and outsourced for treatment.

[0030] Among them, the molar ratio of lithium fluoride, boron trifluoride and oxalic acid is 1:1.1:1.

[0031] (7): The alkali liquid in the alkali liquid storage device 28 is transported to the exhaust gas absorption reactor 31. After the gas generated during the reaction is passed into the exhaust gas absorption reactor 31 containing a large amount of alkali liquid, the solution is pumped to negative pressure through the vacuum pump in the auxiliary agent recovery tower 32, and the temperature is increased by a temperature regulating tank to degas and concentrate, and impurities such as water are removed, and then the temperature is reduced and liquefied, and then pumped to the auxiliary agent storage device 27 for storage and reuse.

[0032] When the reactor body 3 is in the reaction process, the driving motor 9 is started, and the output end of the driving motor 9 drives the rotating shaft 10 to rotate, and the rotating shaft 10 drives the cam 12 to rotate, and a plurality of micro-channels 7 are elastically connected in the reactor body 3, and the plurality of micro-channels 7 are limited by the fixing ring 8. When the raised position of the cam 12 passes through the raised block 11, a thrust is generated on the raised block 11, so that the micro-channel 7 is shaken, and the reaction time between the lithium fluoride solution, boron trifluoride gas, oxalic acid, alkali solution, auxiliary agent or dimethyl carbonate and other solvents located in the micro-channel 7 is accelerated, so as to improve the efficiency of preparing lithium difluorooxalate borate, and at the same time, the recycling of the auxiliary agent is realized, and the reduction Less environmental pollution, improved product quality, and reduced intermediate links. In this equipment system, hexamethyldisiloxane, hexamethyldisilazane or tetramethyldisiloxane are used as additives in the production process. The design and use of the recovery section effectively solves the problem of traditional silicon tetrachloride additives producing silicon tetrafluoride and hydrogen fluoride, and the additives are recovered and put into reproduction, which greatly reduces the consumption of additives and solves the problems of corrosion equipment during production and pipeline blockage during tail gas treatment. The entire production process is continuous and smooth, the key equipment has stable performance and long service life, the system additives are recycled, the utilization rate is high, the cost is greatly reduced, and no waste gas is generated. It is a new type of environmentally friendly and energy-saving production equipment.

[0033] Among them, the driving motor 9 mentioned above can be purchased on the market. It is a mature technology and has been fully disclosed, so it is not repeated in the specification. The driving motor 9 is equipped with a power connection line, and it is electrically connected to the external main controller and 220V phase voltage (or 380V line voltage) through the power line, and the main controller can be a conventional known device such as a computer that plays a control role.

[0034] As a technical optimization solution of the present invention, a plurality of annular feed pipes 13 connected to the outside are provided in the shell 6, and elastic tubes 14 are installed at both ends of the upper and lower ends of the plurality of micro-channels 7. The elastic tubes 14 are elastic and have electrically controlled magnetic valves inside. Connecting pipes 15 are provided between the plurality of micro-channels 7, and the connecting pipes 15 are connected to the annular feed pipe 13.

[0035] Specifically, the elastic tube 14 is elastic, and each elastic tube 14 is sealed and connected to the micro-channel 7. The lithium fluoride solution, boron trifluoride gas, oxalic acid, alkali solution, additives and dimethyl carbonate solvent are fed through the corresponding annular feed pipes 13, and each micro-channel 7 is connected through a connecting pipe 15. An electrically controlled magnetic valve is provided in each elastic tube 14, which can open and close the micro-channel 7.

[0036] As a technical optimization scheme of the present invention, an upper sealing plate 16 and a lower sealing plate 17 are respectively sealed and installed in the upper and lower parts of the shell 6, a plurality of elastic tubes 14 penetrate the upper sealing plate 16 and the lower sealing plate 17, a rotating shaft 10 penetrates the upper sealing plate 16 and the lower sealing plate 17, a discharge bin 18 is fixedly installed on the lower surface of the lower sealing plate 17, the discharge bin 18 is connected to the vacuum concentration tower 5, a plurality of heating rods 19 are penetrated and installed between the two fixed rings 8, and the upper sealing plate 16 and the lower sealing plate 17 are filled with heat exchange medium.

[0037] Specifically, the upper sealing plate 16 and the lower sealing plate 17 are used for sealing. A heatable medium is filled between the upper sealing plate 16 and the lower sealing plate 17. The heatable medium can be heated by turning on the heating rod 19. At the same time, the cam 12 and the protruding block 11 are cooperated to drive the heating rod 19 to stir the heat exchange medium between the upper sealing plate 16 and the lower sealing plate 17 when the fixing ring 8 is shaken, thereby improving the heating efficiency of the heat exchange medium and the heat exchange efficiency between the heat exchange medium and the micro-channel 7.

[0038] As a technical optimization solution of the present invention, blades 20 are fixedly installed on the side of the rotating shaft 10. The blades 20 are divided into two groups and are respectively located on the back sides of the two fixing rings 8.

[0039] Specifically, when it is necessary to add reaction raw materials into the micro-channel 7, the electrically controlled magnetic valves in all the elastic tubes 14 on the lower surface of the upper sealing plate 16 are opened, and the drive motor 9 is turned on. The output end of the drive motor 9 drives the rotating shaft 10 to rotate, and the rotating shaft 10 drives the paddle 20 to rotate, thereby accelerating the reaction raw materials to enter the micro-channel 7. When the reactants need to be discharged after the reaction is completed, the electrically controlled magnetic valves in all the elastic tubes 14 on the upper surface of the lower sealing plate 17 are opened, and the output end of the drive motor 9 drives the paddle 20 to rotate, thereby accelerating the efficiency of the discharge of the reactants.

[0040] As a technical optimization solution of the present invention, a sleeve 21 is fixedly installed on the side of the rotating shaft 10 , and a feed auger 22 is fixedly installed on the side of the rotating shaft 10 . The feed auger 22 is located in the sleeve 21 and is adapted to the sleeve 21 .

[0041] Specifically, when the driving motor 9 drives the rotating shaft 10 to rotate, the rotating shaft 10 drives the feeding auger 22 to rotate, and the feeding auger 22 transports the heat exchange medium located in the lower part of the reactor body 3 to the upper part of the reactor body 3, thereby improving the heat exchange rate of the heat exchange medium in the reactor body 3.

[0042] As a technical optimization solution of the present invention, a plurality of guide columns 35 are fixedly installed on the inner wall of the shell 6, and a guide groove 34 adapted to the guide column 35 is opened on the side of the fixing ring 8. Two bearings 36 are sleeved on the side of each guide column 35, and a spring 33 sleeved on the side of the guide column 35 is provided between the two bearings 36.

[0043] Specifically, when the rotating shaft 10 drives the cam 12 to squeeze the protruding block 11, the spring 33 at the position corresponding to the protruding block 11 is compressed, and at the same time, the remaining guide columns 35 slide laterally in the guide groove 34, thereby improving the automatic return effect of the fixing ring 8. When the rotating shaft 10 does not rotate, the position of the fixing ring 8 is limited, and the bearing 36 reduces the friction coefficient between the spring 33 and the side of the fixing ring 8.

[0044] Finally, it should be noted that in the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0045] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A circulating reactor for producing lithium difluorooxalate borate, characterized in that: include: A material storage unit (1), a material mixing unit (2), a reactor body (3), an auxiliary agent recovery unit (4) and a vacuum concentration tower (5); The material storage unit (1) is used to store a plurality of solid or liquid reaction raw materials, the material mixing unit (2) is used to mix the plurality of reaction raw materials stored in the material storage unit (1), the reactor body (3) is used to carry out a chemical reaction on the plurality of reaction raw materials, the auxiliary agent recovery unit (4) is used to recover the reaction raw materials, and the vacuum concentration tower (5) is used to concentrate the product after the reaction of the reactor body (3); The reactor body (3) comprises a shell (6), a plurality of micro-channels (7) are elastically connected inside the shell (6), a fixing ring (8) for fixing the micro-channels (7) is provided inside the reactor body (3), a driving motor (9) is provided inside the reactor body (3), a rotating shaft (10) concentric with the fixing ring (8) is fixedly mounted on the output end of the driving motor (9), a plurality of protruding blocks (11) are fixedly connected to the inner side wall of the fixing ring (8), and a cam (12) adapted to the protruding blocks (11) is fixedly connected to the side of the rotating shaft (10).

2. The circulating reactor for producing lithium difluorooxalate borate according to claim 1, characterized in that: A plurality of annular feed pipes (13) connected to the outside are arranged in the shell (6); elastic tubes (14) are installed at both upper and lower ends of the plurality of micro-channels (7); the elastic tubes (14) are elastic and have an electrically controlled magnetic valve arranged therein; and connecting pipes (15) are arranged between the plurality of micro-channels (7), and the connecting pipes (15) are connected to the annular feed pipe (13).

3. The circulating reactor for producing lithium difluorooxalate borate according to claim 2, characterized in that: An upper sealing plate (16) and a lower sealing plate (17) are respectively installed in a sealed manner at the upper and lower parts of the shell (6); a plurality of the elastic tubes (14) penetrate the upper sealing plate (16) and the lower sealing plate (17); the rotating shaft (10) penetrates the upper sealing plate (16) and the lower sealing plate (17); a discharge bin (18) is fixedly installed on the lower surface of the lower sealing plate (17); and the discharge bin (18) is connected to the vacuum concentration tower (5).

4. The circulating reactor for producing lithium difluorooxalate borate according to claim 3, characterized in that: A plurality of heating rods (19) are installed through the two fixing rings (8), and the upper sealing plate (16) and the lower sealing plate (17) are both filled with heat exchange medium.

5. The circulating reactor for producing lithium difluorooxalate borate according to claim 1, characterized in that: Paddle blades (20) are fixedly mounted on the side of the rotating shaft (10), and the paddle blades (20) are in two groups and are respectively located on the back sides of two fixing rings (8).

6. The circulating reactor for producing lithium difluorooxalate borate according to claim 3, characterized in that: A sleeve (21) is fixedly mounted on the side of the rotating shaft (10), and a material conveying auger (22) is fixedly mounted on the side of the rotating shaft (10); the material conveying auger (22) is located inside the sleeve (21) and is adapted to fit the sleeve (21).

7. The circulating reactor for producing lithium difluorooxalatoborate according to claim 1, characterized in that: The material storage unit (1) comprises a boron trifluoride storage device (23) for storing boron trifluoride, a lithium fluoride storage device (24) for storing lithium fluoride, a dimethyl carbonate storage device (25) for storing dimethyl carbonate, an oxalic acid storage device (26) for storing oxalic acid, an auxiliary agent storage device (27) for storing auxiliary agents, and an alkali solution storage device (28) for storing alkali solution.

8. The circulating reactor for producing lithium difluorooxalatoborate according to claim 7, characterized in that: The mixing unit (2) comprises two mixing devices, a first-stage mixing device (29) and a second-stage mixing device (30), which are located between the storage unit (1) and the reactor body (3). The first-stage mixing device (29) is used to mix the raw materials in the lithium fluoride storage device (24) and the dimethyl carbonate storage device (25), and the second-stage mixing device (30) is used to mix the raw materials in the dimethyl carbonate storage device (25) and the oxalic acid storage device (26). The raw materials mixed by the mixing unit (2) are all transported to the reactor body (3), and the boron trifluoride storage device (23) and the auxiliary agent storage device (27) directly supply materials to the reactor body (3).

9. The circulating reactor for producing lithium difluorooxalate borate according to claim 7, characterized in that: The auxiliary agent recovery unit (4) comprises a waste gas absorption reactor (31) and an auxiliary agent recovery tower (32); the upper end of the waste gas absorption reactor (31) is connected to the upper end of the reactor body (3); the auxiliary agent recovery tower (32) is connected to the auxiliary agent storage device (27); and the alkali solution storage device (28) is connected to the waste gas absorption reactor (31).

10. The circulating reactor for producing lithium difluorooxalate borate according to claim 1, characterized in that: A plurality of guide posts (35) are fixedly mounted on the inner wall of the housing (6); a guide groove (34) adapted to the guide posts (35) is provided on the side of the fixing ring (8); two bearings (36) are sleeved on the side of each guide post (35); and a spring (33) sleeved on the side of the guide post (35) is provided between the two bearings (36).

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