Lithium hexafluorophosphate synthesis reaction kettle

Abstract

The utility model relates to a lithium hexafluorophosphate synthesis reaction kettle. The lithium hexafluorophosphate synthesis reaction kettle comprises a kettle body, a reaction liquid inlet pipe is arranged on the kettle body, a gas outlet pipe is arranged on the kettle body, a deep freezer is arranged on the gas outlet pipe, a gas distributor is arranged on the lower side in the kettle body, a reaction gas inlet pipe communicated with the gas distributor is arranged on the kettle body, and a gas outlet pipe communicated with the gas distributor is arranged on the reaction gas inlet pipe. An upper stirring shaft and a lower stirring shaft are rotatably mounted in the kettle body, the lower stirring shaft and the upper stirring shaft are coaxially arranged, a transmission mechanism for realizing reverse rotation of the upper stirring shaft and the lower stirring shaft is arranged in the kettle body, and a driving mechanism for driving the upper stirring shaft to rotate is arranged on the kettle body. Phosphorus pentafluoride gas can enter the kettle body more dispersedly through the gas distributor, so that the dispersity of reaction gas in reaction liquid is improved, and the reaction rate and the utilization rate of the reaction liquid are improved. The upper stirring shaft and the lower stirring shaft which rotate in opposite directions simultaneously stir the reaction liquid in the kettle body, so that the mixing effect of the reaction liquid and the reaction gas is enhanced, and the reaction rate is increased. And the reacted liquid is discharged through a discharge pipe at the bottom, and the gas is discharged after part of phosphorus pentafluoride flows back through a deep freezer.

Description

Technical Field

[0001] The utility model belongs to the technical field of lithium hexafluorophosphate production equipment, and particularly relates to a lithium hexafluorophosphate synthesis reactor. Background Technique

[0002] As the most widely commercialized lithium-ion battery electrolyte, lithium hexafluorophosphate has good ionic conductivity and electrochemical stability, and has become the core raw material for producing lithium-ion battery electrolytes, accounting for about 43% of the total cost of electrolytes. With the rapid development of the new energy industry, its market demand has increased sharply, and the development prospect is good.

[0003] At present, the main domestic and foreign preparation processes of lithium hexafluorophosphate include hydrofluoric acid solvent method, gas-solid reaction method, organic solvent method, ion exchange method, etc. Among them, the hydrofluoric acid solvent method is the most important industrial production method at present. The process is to dissolve lithium fluoride in anhydrous hydrofluoric acid to prepare a lithium fluoride solution, and then charge phosphorus pentafluoride gas into the solution for gas-liquid reaction to generate lithium hexafluorophosphate, which has the advantages of fast reaction speed, easy reaction control, high product conversion rate, relatively few side reactions, and high product purity.

[0004] The preparation of lithium hexafluorophosphate by the hydrofluoric acid solvent method mainly involves the reaction of phosphorus pentachloride and anhydrous hydrofluoric acid to generate phosphorus pentafluoride gas, which is then introduced into a LiF·HF solution formed by dissolving lithium fluoride in anhydrous hydrofluoric acid for reaction to obtain a synthesis solution, and then the product is obtained through cooling crystallization, separation and drying. During the preparation process, it is often necessary to put phosphorus pentafluoride gas and an anhydrous hydrofluoric acid solution containing lithium fluoride into a synthesis kettle for crystallization reaction to obtain pure lithium hexafluorophosphate. In the existing synthesis kettles, the reaction gas is mostly injected directly on the surface of the reaction liquid, resulting in problems such as low reaction rate and low utilization rate of the reaction liquid. In addition, the stirring rod in the existing synthesis kettle stirs the reaction liquid in the kettle body by one-way rotation, and the reaction liquid and the reaction gas are not mixed sufficiently, resulting in a low reaction rate. Content of the Utility Model

[0005] In order to solve the above technical problems, the utility model provides a lithium hexafluorophosphate synthesis reactor.

[0006] The technical solution of a lithium hexafluorophosphate synthesis reactor of the utility model is as follows:

[0007] A lithium hexafluorophosphate synthesis reactor includes a reactor body. A reaction liquid inlet pipe is provided on the reactor body. An air outlet pipe is provided on the reactor body. A cryogenic cooler is provided on the air outlet pipe. A gas distributor is provided on the lower side inside the reactor body. A reaction gas inlet pipe communicating with the gas distributor is provided on the reactor body. An upper stirring shaft and a lower stirring shaft arranged coaxially with the upper stirring shaft are rotatably installed inside the reactor body. A transmission mechanism for enabling the upper stirring shaft and the lower stirring shaft to rotate in opposite directions is provided inside the reactor body. A driving mechanism for driving the upper stirring shaft to rotate is provided on the reactor body.

[0008] Further, the upper stirring shaft is rotatably installed at the upper end of the reactor body through a bearing. A mounting plate is fixedly connected to the inner wall of the lower side of the reactor body. The lower stirring shaft is rotatably installed on the mounting plate through a bearing.

[0009] Further, the transmission mechanism includes a sleeve, a connecting rod, a driving gear, a transmission gear, and a driven gear. The sleeve is sleeved on the lower end of the upper stirring shaft and the upper end of the lower stirring shaft. Two ends of the connecting rod are respectively fixedly connected to the sleeve and the inner wall of the reactor body. The driving gear is fixedly connected to the lower end of the upper stirring shaft. The driven gear is fixedly connected to the upper end of the lower stirring shaft. The transmission gear is rotatably installed inside the sleeve. The transmission gear meshes with the driving gear and the driven gear respectively.

[0010] Further, sealing bearings are respectively installed between the sleeve and the upper stirring shaft and the lower stirring shaft.

[0011] Further, a motor fixing seat is fixedly connected to the upper side of the reactor body. The upper end of the upper stirring shaft extends into the motor fixing seat. The driving mechanism includes a reduction motor. The output shaft of the reduction motor extends into the motor fixing seat. The output shaft of the reduction motor is fixedly connected to the upper end of the upper stirring shaft through a coupling.

[0012] Further, a jacket is fixedly connected to the outer wall of the reactor body. A heat exchange cavity is formed between the jacket and the reactor body. A heat exchange medium inlet pipe and a heat exchange medium outlet pipe are provided on the jacket. The heat exchange medium inlet pipe and the heat exchange medium outlet pipe are located on both sides of the jacket. The heat exchange medium inlet pipe is located below the heat exchange medium outlet pipe.

[0013] Further, a discharge pipe is provided at the lower end of the reactor body. A first stop valve is provided on the discharge pipe. A second stop valve is provided on the reaction liquid inlet pipe. A third stop valve is provided on the reaction gas inlet pipe. A fourth stop valve is provided on the air outlet pipe.

[0014] The present utility model provides a lithium hexafluorophosphate synthesis reactor, and its beneficial effects are:

[0015] When the lithium hexafluorophosphate synthesis reactor of the present utility model is in use, the LiF·HF synthesis liquid is added into the reactor body through the reaction liquid inlet pipe, and the phosphorus pentafluoride gas is added into the reactor body through the reaction gas inlet pipe. The phosphorus pentafluoride gas can enter the reactor body more dispersedly through the gas distributor, improving the dispersion degree of the reaction gas in the reaction liquid, and enhancing the reaction rate and the utilization rate of the reaction liquid. The reduction motor is started, and the reduction motor drives the upper stirring shaft to rotate. The upper stirring shaft drives the lower stirring shaft to rotate through the driving gear, the transmission gear and the driven gear. The rotation directions of the upper stirring shaft and the lower stirring shaft are opposite. The upper stirring shaft and the lower stirring shaft with opposite rotation directions simultaneously stir the reaction liquid in the reactor body, enhancing the mixing effect of the reaction liquid and the reaction gas, thereby improving the reaction rate. The reacted liquid is discharged through the discharge pipe at the bottom, and the gas is discharged after part of the phosphorus pentafluoride is refluxed through the cryogenic cooler. Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of the lithium hexafluorophosphate synthesis reactor of the present utility model;

[0017] Figure 2 is Figure 1 the enlarged view of part A in

[0018] In the figure: 1, reactor body; 2, reaction liquid inlet pipe; 3, discharge pipe; 4, gas outlet pipe; 5, cryogenic cooler; 6, reaction gas inlet pipe; 7, first stop valve; 8, second stop valve; 9, third stop valve; 10, fourth stop valve; 11, jacket; 12, heat exchange cavity; 13, heat exchange medium inlet pipe; 14, heat exchange medium outlet pipe; 15, gas distributor; 16, upper stirring shaft; 17, lower stirring shaft; 18, mounting plate; 19, connecting rod; 20, sleeve; 21, driving gear; 22, driven gear; 23, transmission gear; 24, sealing bearing; 25, motor fixing seat; 26, reduction motor; 27, coupling. Detailed Embodiments

[0019] The present utility model will be further described in detail below in conjunction with the drawings and specific embodiments:

[0020] A specific embodiment of the lithium hexafluorophosphate synthesis reactor of the present utility model is as Figure 1 、 Figure 2As shown in the figure, it includes a kettle body 1. The kettle body 1 has a cylindrical structure. The upper end of the kettle body 1 has a top structure with an arc-shaped upward convexity, and the lower end of the kettle body 1 has a bottom structure with an arc-shaped downward convexity. A discharge pipe 3 is welded at the central position of the lower end of the kettle body 1. A first stop valve 7 is installed on the discharge pipe 3, and the first stop valve 7 is used to control the on-off of the discharge pipe 3. The upper end of the kettle body 1 has a reaction liquid inlet pipe 2, and the reaction liquid inlet pipe 2 extends downward into the interior of the kettle body 1 near the bottom. The kettle body 1 also has an air outlet pipe 4. A cryogenic cooler 5 is installed on the air outlet pipe 4, and the cryogenic cooler 5 is used to reflux phosphorus pentafluoride gas after the reaction ends. A gas distributor 15 is installed near the bottom inside the kettle body 1, and the kettle body 1 has a reaction gas inlet pipe 6 communicated with the gas distributor 15. A second stop valve 8 is installed on the reaction liquid inlet pipe 2, a third stop valve 9 is installed on the reaction gas inlet pipe 6, and a fourth stop valve 10 is installed on the air outlet pipe 4.

[0021] In this embodiment, an upper stirring shaft 16 and a lower stirring shaft 17 arranged coaxially with the upper stirring shaft 16 are rotatably installed inside the kettle body 1. There is a transmission mechanism inside the kettle body 1 for realizing the reverse rotation of the upper stirring shaft 16 and the lower stirring shaft 17, and a driving mechanism for driving the upper stirring shaft 16 to rotate is provided on the kettle body 1. The upper stirring shaft 16 is rotatably installed at the central position of the upper end of the kettle body 1 through a bearing. An installation plate 18 is fixedly connected to the inner wall on the lower side of the kettle body 1, and the lower stirring shaft 17 is rotatably installed on the installation plate 18 through a bearing.

[0022] In this embodiment, the transmission mechanism includes a sleeve 20, a connecting rod 19, a driving gear 21, a transmission gear 23 and a driven gear 22. The sleeve 20 is sleeved on the lower end of the upper stirring shaft 16 and the upper end of the lower stirring shaft 17. Two ends of the connecting rod 19 are respectively fixedly connected with the sleeve 20 and the inner wall of the kettle body 1. The driving gear 21 is fixedly connected to the lower end of the upper stirring shaft 16, the driven gear 22 is fixedly connected to the upper end of the lower stirring shaft 17, the transmission gear 23 is rotatably installed inside the sleeve 20, and the transmission gear 23 meshes with the driving gear 21 and the driven gear 22 respectively. In order to reduce the influence of the reaction liquid on the driving gear 21, the driven gear 22 and the transmission gear 23, sealing bearings 24 are respectively installed between the sleeve 20 and the upper stirring shaft 16 and the lower stirring shaft 17.

[0023] In this embodiment, a motor fixing seat 25 is fixedly connected to the upper side of the kettle body 1, and the upper end of the upper stirring shaft 16 extends into the motor fixing seat 25. The driving mechanism includes a reduction motor 26. The output shaft of the reduction motor 26 extends into the motor fixing seat 25, and the output shaft of the reduction motor 26 is fixedly connected to the upper end of the upper stirring shaft 16 through a coupling 27. An outer jacket 11 is fixedly connected to the outer wall of the kettle body 1. A heat exchange cavity 12 is formed between the outer jacket 11 and the kettle body 1. A heat exchange medium inlet pipe 13 and a heat exchange medium outlet pipe 14 are provided on the outer jacket 11. The heat exchange medium inlet pipe 13 and the heat exchange medium outlet pipe 14 are located on both sides of the outer jacket 11, and the heat exchange medium inlet pipe 13 is located below the heat exchange medium outlet pipe 14.

[0024] When the lithium hexafluorophosphate synthesis reactor of the present utility model is in use, the LiF·HF synthesis liquid is added into the reactor body 1 through the reaction liquid inlet pipe 2, and the phosphorus pentafluoride gas is added into the reactor body 1 through the reaction gas inlet pipe 6. The phosphorus pentafluoride gas can enter the reactor body 1 more dispersedly through the gas distributor 15, improving the dispersion degree of the reaction gas in the reaction liquid, and improving the reaction rate and the utilization rate of the reaction liquid. The reduction motor 26 is started, and the reduction electric drive rotates the upper stirring shaft 16. The upper stirring shaft 16 drives the lower stirring shaft 17 to rotate through the driving gear 21, the transmission gear 23 and the driven gear 22. The rotation directions of the upper stirring shaft 16 and the lower stirring shaft 17 are opposite. The upper stirring shaft 16 and the lower stirring shaft 17 with opposite rotation directions simultaneously stir the reaction liquid in the reactor body 1, enhancing the mixing effect of the reaction liquid and the reaction gas, thereby improving the reaction rate. The reacted liquid is discharged through the discharge pipe 3 at the bottom, and the gas is discharged after part of the phosphorus pentafluoride is refluxed through the cryogenic cooler 5.

[0025] The above are only the preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A lithium hexafluorophosphate synthesis reactor, characterized in that: The invention comprises a kettle body, wherein the kettle body is provided with a reaction liquid inlet pipe, the kettle body is provided with an air outlet pipe, the air outlet pipe is provided with a deep cooler, a gas distributor is provided on the lower side of the kettle body, the kettle body is provided with a reaction gas inlet pipe connected with the gas distributor, an upper stirring shaft and a lower stirring shaft coaxially arranged with the upper stirring shaft are rotatably installed in the kettle body, a transmission mechanism for realizing the reverse rotation of the upper stirring shaft and the lower stirring shaft is provided in the kettle body, and a driving mechanism for driving the upper stirring shaft to rotate is provided on the kettle body.

2. The lithium hexafluorophosphate synthesis reactor according to claim 1, characterized in that: The upper stirring shaft is rotatably mounted on the upper end of the kettle body via a bearing, a mounting plate is fixedly connected to the lower inner wall of the kettle body, and the lower stirring shaft is rotatably mounted on the mounting plate via a bearing.

3. The lithium hexafluorophosphate synthesis reactor according to claim 2, characterized in that: The transmission mechanism includes a sleeve, a connecting rod, a driving gear, a transmission gear and a driven gear. The sleeve is sleeved on the lower end of the upper stirring shaft and the upper end of the lower stirring shaft. The two ends of the connecting rod are respectively fixedly connected to the sleeve and the inner wall of the kettle body. The driving gear is fixedly connected to the lower end of the upper stirring shaft, and the driven gear is fixedly connected to the upper end of the lower stirring shaft. The transmission gear is rotatably installed in the sleeve, and the transmission gear is respectively meshed with the driving gear and the driven gear.

4. The lithium hexafluorophosphate synthesis reactor according to claim 3, characterized in that: Sealed bearings are respectively installed between the sleeve and the upper stirring shaft and the lower stirring shaft.

5. The lithium hexafluorophosphate synthesis reactor according to claim 2, characterized in that: A motor fixing seat is fixedly connected to the upper side of the kettle body, the upper end of the upper stirring shaft extends into the motor fixing seat, the driving mechanism includes a reduction motor, the output shaft of the reduction motor extends into the motor fixing seat, and the output shaft of the reduction motor is fixedly connected to the upper end of the upper stirring shaft through a coupling.

6. The lithium hexafluorophosphate synthesis reactor according to claim 1, characterized in that: A jacket is fixedly connected to the outer wall of the kettle body, a heat exchange cavity is formed between the jacket and the kettle body, a heat exchange medium inlet pipe and a heat exchange medium outlet pipe are arranged on the jacket, the heat exchange medium inlet pipe and the heat exchange medium outlet pipe are located on both sides of the jacket, and the heat exchange medium inlet pipe is located at the lower side of the heat exchange medium outlet pipe.

7. The lithium hexafluorophosphate synthesis reactor according to claim 1, characterized in that: A discharge pipe is provided at the lower end of the kettle body, a first stop valve is provided on the discharge pipe, a second stop valve is provided on the reaction liquid inlet pipe, a third stop valve is provided on the reaction gas inlet pipe, and a fourth stop valve is provided on the gas outlet pipe.

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