A high-efficiency synthesis device for synthesizing lithium hexafluorophosphate

Abstract

The invention discloses a highly efficient synthesis device for synthesizing lithium hexafluorophosphate, which comprises: a main cavity for containing low-temperature anhydrous hydrofluoric acid; a cover for sealing the main cavity to prevent leakage of gas entering the main cavity; a gas supply convex plate evenly embedded in the side wall of the main cavity, which is an integrated structure with the main cavity and is provided with a plurality of one-way gas delivery valves; a gas delivery device, comprising a gas delivery cavity and a plurality of gas delivery pipelines evenly connected to one side of the gas delivery cavity, the gas delivery cavity being connected to the gas supply convex plate and the one-way gas delivery valve thereon; and a stirring device, comprising a rotating shaft driven by a motor and an impeller arranged on the rotating shaft. The contact area between the gas and the solution is greatly increased, and at the same time, the contact position between the gas and the solution is made more uniform, which solves the problem that the gas in the existing ventilation method is easy to repeatedly contact with the local solution, while reducing the chance of contact with other parts of the solution, resulting in insufficient reaction and reduced synthesis efficiency of lithium hexafluorophosphate.

Description

Technical Field

[0001] The invention is applied to the field of lithium hexafluorophosphate manufacturing, and specifically is a high-efficiency synthesis device for synthesizing lithium hexafluorophosphate. Background Art

[0002] Lithium hexafluorophosphate is the most important component of electrolyte, accounting for about 43% of the total cost of electrolyte. In the fluorine chemical industry, although the year-on-year decline in traditional products is obvious, the growth in demand for high-end products has maintained a strong momentum. In particular, the production and sales of lithium hexafluorophosphate continue to maintain a good trend. With the continued expansion of the new energy field in the future, lithium hexafluorophosphate is expected to usher in a continuous outbreak. In the future, other new lithium salts are expected to replace lithium hexafluorophosphate. The specific steps of manufacturing lithium hexafluorophosphate by wet method are to dissolve the lithium salt in anhydrous hydrogen fluoride to form LiF·HF solution, and then introduce PF5 gas to react and produce lithium hexafluorophosphate crystals. After separation and drying, the product is obtained. How to make the LiF·HF solution formed by dissolving lithium salt in anhydrous hydrogen fluoride react fully with PF5 gas in the overall process is the key to the synthesis efficiency of lithium hexafluorophosphate. The existing methods of introducing PF5 gas mostly use aeration pipes to introduce PF5 gas into the solution, or install the aeration pipes inside the stirring equipment to allow ventilation during stirring to increase the contact opportunity between the gas and the solution and thus perform aeration operation. However, in this method, the contact area between PF5 gas and the solution is still not large enough, and the ventilation device is prone to repeatedly contact with the local solution, while reducing the opportunity of contact with the solution in other parts, resulting in insufficient reaction and reducing the synthesis efficiency of lithium hexafluorophosphate. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a high-efficiency synthesis device for synthesizing lithium hexafluorophosphate in view of the deficiencies of the prior art.

[0004] In order to solve the above technical problems, the present invention provides an efficient synthesis device for synthesizing lithium hexafluorophosphate, which comprises:

[0005] The main chamber is used to contain low-temperature anhydrous hydrofluoric acid, and is divided into a reaction chamber and an operation chamber by a partition;

[0006] The cover body is hingedly installed with the main cavity and is used to seal the main cavity to prevent gas leakage into the main cavity;

[0007] The air supply convex disc is evenly embedded in the side wall of the main cavity, and is an integrated structure with the main cavity, and is provided with multiple sets of one-way air supply valves;

[0008] The gas delivery device comprises a gas delivery cavity and a plurality of gas delivery pipelines uniformly connected to one side of the gas delivery cavity, wherein the gas delivery cavity is connected to the gas supply convex disc and a one-way gas delivery valve thereon;

[0009] The stirring device comprises a rotating shaft driven by a motor and an impeller arranged on the rotating shaft. One end of the rotating shaft passes through the partition and is rotatably connected thereto, and the other end of the rotating shaft is transmission-connected to the motor arranged in the operating chamber.

[0010] As a possible implementation manner, further, the main cavity is a cylindrical tank body, and its side wall is a double-layer insulation structure.

[0011] As a possible implementation mode, further, PF5 gas is introduced into one end of the gas pipeline, passes through the gas delivery cavity, and then enters the reaction cavity through a one-way gas delivery valve provided on the gas supply convex disc that allows the gas to be delivered inward.

[0012] As a possible implementation mode, further, one end of the rotating shaft passing through the partition is connected to a main bevel gear, and four groups of motors are symmetrically installed in a ring with the rotating shaft as the center in the operating chamber, and the output shafts of the motors are connected to secondary bevel gears, and the secondary bevel gears are meshed with the main bevel gears. The rotation of the motor drives the main bevel gear to rotate through the secondary bevel gears to achieve the purpose of driving the rotating shaft to rotate.

[0013] As a possible implementation manner, further, the other end of the rotating shaft is rotatably connected to the main cavity through a mounting bracket.

[0014] As a possible implementation manner, further, the impeller adopts an arc-shaped impeller.

[0015] As a possible implementation manner, further, the length of the impeller blades arranged on the rotating shaft increases from bottom to top.

[0016] As a possible implementation mode, further, a group of one-way air supply valves is provided through the center of the air supply boss, and another four groups of one-way air supply valves are evenly arranged in a ring around the central one-way air supply valve on the air supply boss, and the four groups of one-way air supply valves arranged in a ring are opened outward and the air supply direction is perpendicular to the surface of the air supply boss.

[0017] The present invention adopts the above technical solution and has the following beneficial effects:

[0018] 1. By using the gas supply convex plate and the gas delivery device arranged on the side wall of the reaction chamber to perform the gas delivery operation, the PF5 gas is uniformly introduced from all angles of the side wall of the reaction chamber, the contact points and contact areas between the solution and the gas are increased at the introduction end, and the stirring device is arranged to make the lithium salt fully dissolved in the anhydrous hydrofluoric acid. At the same time, the LiF·HF solution is rotated and a water lifting effect is generated under the drive of the stirring device, so that the water lifting height is increased, and the LiF·HF solution is lifted upward along the side wall of the reaction chamber to fully contact with the PF5 gas output by the one-way gas delivery valve on the gas supply convex plate on the side wall of the reaction chamber. Compared with the traditional method of using an aeration pipe to introduce PF5 gas into the solution, or installing the aeration pipe inside the stirring device to ventilate during stirring to increase the contact opportunity between the gas and the solution and thus perform the ventilation operation, the contact area between the gas and the solution is greatly increased, and the contact position between the gas and the solution is made more uniform, which solves the problem that the gas in the existing ventilation method is easy to repeatedly contact with the local solution, while reducing the chance of contacting with other parts of the solution, resulting in insufficient reaction and reduced synthesis efficiency of lithium hexafluorophosphate.

[0019] 2. The impeller with blade length increasing from bottom to top is provided so that the torque on the end of the rotating shaft, i.e., the end connected to the motor transmission, is reduced during the rotation process, thereby solving the problem of the transmission end of the traditional stirring equipment being broken due to excessive torque on the transmission end. The impeller with blade length increasing from bottom to top can extend the service life of the stirring device by reducing the torque on the transmission end, while ensuring that the stirring device can generate sufficient centrifugal force to stir the LiF·HF solution, so that the solution is lifted up and fully contacts with the PF5 gas output by the one-way gas valve on the gas supply convex disc, thereby improving the reaction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0021] Figure 1 It is a schematic diagram of the external structure of the present invention;

[0022] Figure 2 It is a schematic diagram of the internal structure of the present invention;

[0023] Figure 3 It is a cross-sectional view of the impeller structure of the present invention;

[0024] Figure 4 It is a schematic diagram of the layout of the one-way gas supply valve on the surface of the gas supply convex disc of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0026] like Figure 1-4 As shown, the present invention provides an efficient synthesis device for synthesizing lithium hexafluorophosphate, which comprises:

[0027] The main cavity 1 is used to contain low-temperature anhydrous hydrofluoric acid, and is divided into a reaction cavity 102 and an operation cavity 103 by a partition 101; the main cavity 1 is a cylindrical tank, and its side wall is a double-layer insulation structure.

[0028] The cover body 2 is hingedly mounted on the main cavity 1 and is used to seal the main cavity 1 to prevent leakage of gas entering the main cavity 1;

[0029] The gas supply convex disc 3 is evenly embedded in the side wall of the main cavity 1, and is an integrated structure with the main cavity 1, and is provided with multiple groups of one-way gas delivery valves 301; a group of one-way gas delivery valves 301 is provided through the center of the gas supply convex disc 3, and another four groups of one-way gas delivery valves 301 are evenly provided in a ring around the central one-way gas delivery valve 301 on the gas supply convex disc, and the four groups of one-way gas delivery valves 301 arranged in a ring are opened outwards and the gas delivery direction is perpendicular to the surface of the gas supply convex disc 3. By embedding the gas supply convex disc 3 in the side wall of the main cavity 1 and arranging the one-way gas delivery valves 301 perpendicular to the surface of the gas supply convex disc 3 on the gas supply convex disc 3, the number of one-way gas delivery valves 301 that can be arranged on the side wall of the main cavity 1 is significantly increased, and at the same time, the protruding curvature of the gas supply convex disc 3 and the one-way gas delivery valves 301 arranged perpendicular to its surface are used to make the gas input into the main cavity 1 diffuse, thereby increasing the contact area with the solution and preventing the occurrence of uneven contact problems such as local contact that affect the reaction efficiency.

[0030] The gas delivery device 4 includes a gas delivery cavity 401 and a plurality of gas delivery pipes 402 uniformly connected to one side of the gas delivery cavity 401. The gas delivery cavity 401 is connected to the gas supply flange 3 and the one-way gas delivery valve 301 thereon; PF5 gas is introduced into one end of the gas delivery pipe 402, and after passing through the gas delivery cavity 401, it enters the reaction cavity 102 through the one-way gas delivery valve 301 set on the gas supply flange 3 to allow gas to be transported inward.

[0031] The stirring device 5 comprises a rotating shaft 501 driven by a motor 6 and an impeller 502 arranged on the rotating shaft 501. One end of the rotating shaft 501 penetrates the partition 101 and is rotatably connected thereto, and one end of the rotating shaft 501 is transmission-connected to the motor 6 arranged in the operating chamber 103. One end of the rotating shaft 501 penetrating the partition 101 is connected to a main bevel gear. Four groups of motors 6 are annularly symmetrically installed in the operating chamber with the rotating shaft 501 as the center, and the output shafts of the motors 6 are all connected to auxiliary bevel gears, and the auxiliary bevel gears are all meshed with the main bevel gears. The rotation of the motor 6 drives the main bevel gears to rotate through the auxiliary bevel gears to achieve the purpose of driving the rotating shaft 501 to rotate. The other end of the rotating shaft 501 is rotatably connected to the main chamber through the mounting frame 7. The impeller 502 adopts an arc-shaped blade. By utilizing the gas supply convex plate 3 and the gas delivery device 4 disposed on the side wall of the reaction chamber 102 to perform the gas delivery operation, the PF5 gas is uniformly introduced from all angles of the side wall of the reaction chamber 102, and the contact points and contact areas between the solution and the gas are increased at the introduction end. The stirring device 5 is provided to allow the lithium salt to be fully dissolved in the anhydrous hydrofluoric acid. At the same time, the LiF·HF solution rotates and produces a water lifting effect under the drive of the stirring device 5, thereby increasing the water lifting height. The LiF·HF solution is lifted upward along the side wall of the reaction chamber 102 and is connected to the one-way gas supply convex plate on the side wall of the reaction chamber 102. The PF5 gas output by the gas valve 301 is fully in contact with the solution. Compared with the traditional method of using an aeration pipe to pass the PF5 gas into the solution, or installing the aeration pipe inside the stirring device to ventilate during stirring to increase the contact opportunity between the gas and the solution, the contact area between the gas and the solution is greatly increased, and the contact between the gas and the solution is more uniform in position, which solves the problem that the gas in the existing ventilation method is easy to repeatedly contact with the local solution, while reducing the chance of contact with other parts of the solution, resulting in insufficient reaction and reducing the synthesis efficiency of lithium hexafluorophosphate. The length of the blade of the impeller 502 set on the rotating shaft 501 increases from bottom to top.Since the longer the blade of the impeller 502 is, the greater the resistance encountered by the impeller 502 during rotation and the greater the torque experienced by the rotating shaft 501, the impeller 502 is provided with blade lengths that increase from bottom to top, so that the torque experienced by the end of the rotating shaft 501, i.e., the end that is driven by the motor 6, is reduced during rotation, thereby solving the problem of the transmission end breaking due to excessive torque experienced by the transmission end of the conventional stirring equipment. When the impeller 502 rotates to drive the solution to pump water upward, the amount of solution at a high position is small and mostly gathers on the outside close to the side wall of the reaction chamber 102. Therefore, the longer blade at a high position can achieve a better stirring, rotating and pumping effect. At the same time, when the impeller 502 is rotated, the solution at a high position is relatively small and mostly gathers on the outside close to the side wall of the reaction chamber 102. 02 rotates to drive the solution to pump water upward, the amount of solution at the low position is large and mostly gathered on the inner side close to the center of the reaction chamber 102. By setting the impeller 502 with a shorter blade length, the unnecessary resistance of the impeller 502 is reduced and a good pumping effect can be ensured. The impeller 502 with a blade length increasing from bottom to top can achieve the purpose of extending the service life of the stirring device by reducing the torque at the transmission end, while ensuring that the stirring device can generate sufficient centrifugal force to stir the LiF·HF solution to make it pump water upward and fully contact with the PF5 gas output by the one-way gas valve 301 on the gas supply convex disc 3 to improve the reaction efficiency.

[0032] When the device is used to prepare lithium hexafluorophosphate, first, at the required temperature of anhydrous hydrofluoric acid, it is poured into the main cavity 1 through the liquid inlet or by opening the cover 2, and the required temperature is ensured. The cover 2 is opened to put the lithium salt into the main cavity 1 containing the anhydrous hydrofluoric acid, the cover 2 is closed, and the motor 6 is turned on to drive the rotating shaft 501 to rotate to achieve the purpose of the stirring device 5 so that the lithium salt is dissolved in the anhydrous hydrofluoric acid to form a LiF·HF solution. At this time, PF5 gas is introduced into the main cavity 1 by using the connected gas pipeline 402, the gas cavity 401 and the one-way gas valve 301 installed on the gas supply convex plate 3. The rotating stirring device 5 pulls the LiF·HF solution upward to fully contact with the multiple groups of one-way gas valves 301 to react and generate lithium hexafluorophosphate.

[0033] The above are embodiments of the present invention. For ordinary technicians in this field, according to the teachings of the present invention, all equivalent changes, modifications, substitutions and variations made within the scope of the patent application of the present invention without departing from the principles and spirit of the present invention should fall within the scope of the present invention.

Claims

1. An efficient synthesis device for synthesizing lithium hexafluorophosphate, characterized in that: It includes: The main chamber is used to contain low-temperature anhydrous hydrofluoric acid, which is divided into a reaction chamber and an operation chamber by a partition, wherein the reaction chamber is located above the partition, and the operation chamber is located below the partition; The cover body is hingedly installed with the main cavity and is used to seal the main cavity to prevent gas leakage into the main cavity; The gas supply convex disc is evenly embedded in the side wall of the main cavity, and is an integrated structure with the main cavity, and is provided with multiple groups of one-way gas supply valves; a group of one-way gas supply valves is provided through the center of the gas supply convex disc, and another four groups of one-way gas supply valves are evenly provided in a ring around the central one-way gas supply valve on the gas supply convex disc, and the four groups of one-way gas supply valves arranged in a ring are opened outwards and the gas supply direction is perpendicular to the surface of the gas supply convex disc; the gas is diffused when it is input into the main cavity by utilizing the protruding curvature of the gas supply convex disc and the one-way gas supply valves arranged outwards perpendicular to its surface; The gas delivery device comprises a gas delivery cavity and a plurality of gas delivery pipelines uniformly connected to one side of the gas delivery cavity, wherein the gas delivery cavity is connected to the gas supply convex disc and a one-way gas delivery valve thereon; The stirring device comprises a rotating shaft driven by a motor and an impeller arranged on the rotating shaft, wherein the rotating shaft and the impeller are arranged in a reaction chamber, one end of the rotating shaft passes through a partition and is rotatably connected thereto, and one end of the rotating shaft is transmission-connected to a motor arranged inside an operating chamber; the length of the impeller blade increases from bottom to top.

2. The high-efficiency synthesis device for synthesizing lithium hexafluorophosphate according to claim 1, characterized in that: The main cavity is a cylindrical tank body, and its side wall is a double-layer heat-insulating structure.

3. The high-efficiency synthesis device for synthesizing lithium hexafluorophosphate according to claim 1, characterized in that: PF5 gas is introduced into one end of the gas delivery pipeline, and after passing through the gas delivery cavity, it enters the reaction cavity through a one-way gas delivery valve arranged on the gas supply convex disc to allow gas to be delivered inwards.

4. The high-efficiency synthesis device for synthesizing lithium hexafluorophosphate according to claim 1, characterized in that: One end of the rotating shaft passing through the partition is connected to a main bevel gear, and four groups of motors are symmetrically installed in a ring with the rotating shaft as the center in the operating chamber, and the output shafts of the motors are all connected to auxiliary bevel gears, and the auxiliary bevel gears are all meshed with the main bevel gears. The rotation of the motor drives the main bevel gear to rotate through the auxiliary bevel gears to achieve the purpose of driving the rotating shaft to rotate.

5. The high-efficiency synthesis device for synthesizing lithium hexafluorophosphate according to claim 1, characterized in that: The other end of the rotating shaft is rotatably connected to the main cavity through a mounting bracket.

6. The high-efficiency synthesis device for synthesizing lithium hexafluorophosphate according to claim 1, characterized in that: The impeller adopts an arc-shaped blade.

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