Lithium hexafluorophosphate crystallization separation purifier

Abstract

The utility model relates to the technical field of lithium hexafluorophosphate crystallization and purification, and discloses a lithium hexafluorophosphate crystallization, separation and purification device. Comprising a box body and further comprises a feeding port formed in one side of the box body, a sealing plate is arranged at the top of the feeding port, a screening plate for separating a solid-liquid mixture is rotationally connected to the inner wall of the feeding port, and a baffle for preventing crystals from falling off is fixed to the top of the screening plate; a solid-liquid mixture can be separated through the screening plate, wet lithium hexafluorophosphate crystals are obtained, high-purity nitrogen is introduced to expel air out of the box body, phosphorus pentafluoride gas is introduced, heating is started, and after the temperature rises to the drying temperature, the temperature and the flow of the nitrogen and the phosphorus pentafluoride gas are kept for drying. After drying for a certain time, stopping introducing the phosphorus pentafluoride gas, increasing the flow rate of the high-purity nitrogen, and obtaining a purified lithium hexafluorophosphate product after drying is finished.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium hexafluorophosphate crystallization and purification, in particular to a lithium hexafluorophosphate crystallization separation and purification device. Background Art

[0002] Lithium hexafluorophosphate crystals Lithium hexafluorophosphate, as a lithium battery electrolyte, has been widely used in commercial applications because of its balanced performance indicators such as solubility, electrochemical stability, conductivity, high and low temperature performance, and cycle life.

[0003] The existing lithium hexafluorophosphate crystal separation and purification device is usually used in chemical reaction method, thermal vacuum drying method and solvent recrystallization method. The chemical reaction method is easy to introduce other impurities, affecting the purification quality of lithium hexafluorophosphate crystals. The thermal vacuum drying method has a high vacuum degree requirement, is difficult to operate, and easily leads to the decomposition of lithium hexafluorophosphate. The solvent recrystallization method requires lithium hexafluorophosphate to be dissolved in aprotic solvents such as low alkyl ethers, nitriles, alcohols, carbonates, pyridine, etc. for recrystallization and purification, and the process operation is complicated.

[0004] Therefore, it is necessary to provide a new lithium hexafluorophosphate crystal separation purifier to solve the above technical problems. Utility Model Content

[0005] The utility model aims to provide a lithium hexafluorophosphate crystal separation purifier to solve the problems raised in the above background technology.

[0006] To achieve the above object, the utility model provides the following technical solution: a lithium hexafluorophosphate crystallization separation purifier, comprising a box body, and also comprising:

[0007] A feed inlet is arranged on one side of the box body, a sealing plate is arranged on the top of the feed inlet, a sieve plate for separating the solid-liquid mixture is rotatably connected to the inner wall of the feed inlet, and a baffle for preventing crystals from falling is fixed on the top of the sieve plate;

[0008] A mounting frame is fixed to the inner wall of the box, the inner wall of the mounting frame is slidably connected with a filter plate, the top of the filter plate is provided with a scraper for convenient discharge of lithium hexafluorophosphate products, a driving box is provided on one side of the box, a driving mechanism for driving the scraper to move is provided inside the driving box, and a heating rod for heating the lithium hexafluorophosphate crystals is provided on the inner wall of the box.

[0009] Preferably, a support block is fixedly connected to the top of the screen plate, and a guide block is fixedly connected to one side of the support block.

[0010] Preferably, a cylinder is fixedly connected to one side of the box body, a connecting block is fixedly connected to the output end of the cylinder, and a guide frame is fixedly connected to one side of the connecting block.

[0011] Preferably, a liquid storage cavity is provided inside the feed port, and a liquid discharge pipe is provided on one side of the feed port.

[0012] Preferably, the driving mechanism comprises a motor fixed to the inner wall of the driving box, the output end of the motor is fixedly connected to a threaded rod, and the outer side of the threaded rod is threadedly connected to a threaded block.

[0013] Preferably, two groups of fans are arranged at the bottom of the inner cavity of the box, and a temperature sensor is arranged at the bottom of the inner cavity of the box.

[0014] Preferably, a first feed pipe and a second feed pipe are respectively provided on the top of the box body, a sealing cover is provided on the top of each of the first feed pipe and the second feed pipe, and a sealing door is provided on one side of the box body.

[0015] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0016] The utility model can separate the solid-liquid mixture through the screening plate, the liquid flows into the liquid storage cavity to obtain wet lithium hexafluorophosphate crystals, high-purity nitrogen is introduced to drive out the air in the box, then the nitrogen flow is reduced, phosphorus pentafluoride gas is introduced, heating and temperature rise are started, and after the temperature is raised to the drying temperature, the temperature and the nitrogen and phosphorus pentafluoride gas flows are maintained for drying, after drying for a certain time, the heating is turned off, the introduction of phosphorus pentafluoride gas is stopped, the high-purity nitrogen flow is increased, and after a certain time, the drying is completed to obtain a purified lithium hexafluorophosphate product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of a preferred embodiment of a lithium hexafluorophosphate crystallization separation and purification device provided by the utility model;

[0018] Figure 2 This is a schematic diagram of the structure inside the box in the utility model;

[0019] Figure 3 It is a structural schematic diagram of the driving mechanism in the utility model;

[0020] Figure 4 It is a structural schematic diagram of the feed port in the utility model;

[0021] Figure 5 It is a structural schematic diagram of the screening plate in the utility model.

[0022] In the figure: 1. box body; 2. feed inlet; 3. sealing plate; 4. screening plate; 5. baffle; 6. mounting frame; 7. filter plate; 8. scraper; 9. driving mechanism; 91. motor; 92. threaded rod; 93. threaded block; 10. driving box; 11. support block; 12. guide block; 13. cylinder; 14. connecting block; 15. guide frame; 16. liquid storage chamber; 17. drain pipe; 18. fan; 19. temperature sensor; 20. first feed pipe; 21. second feed pipe; 22. sealing cover; 23. heating rod; 24. sealing door. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] See also Figure 1-5 As shown, a lithium hexafluorophosphate crystallization separation and purification device comprises a casing 1, a feed port 2 is arranged on one side of the casing 1, a sealing plate 3 is arranged on the top of the feed port 2, a screening plate 4 is rotatably connected to the inner wall of the feed port 2, a solid-liquid mixture can be separated by the screening plate 4, a baffle 5 is fixed on the top of the screening plate 4, the baffle 5 can prevent crystals from falling, a mounting frame 6 is fixed to the inner wall of the casing 1, a filter plate 7 is slidably connected to the inner wall of the mounting frame 6, a scraper 8 is arranged on the top of the filter plate 7, the scraper 8 is convenient for discharging the lithium hexafluorophosphate product, a driving box 10 is arranged on one side of the casing 1, a driving mechanism 9 is arranged inside the driving box 10, the scraper 8 can be driven to move by the driving mechanism 9, a heating rod 23 is arranged on the inner wall of the casing 1, the heating rod 23 is convenient for heating the lithium hexafluorophosphate crystals.

[0025] refer to Figure 4 and Figure 5As shown, a support block 11 is fixedly connected to the top of the screening plate 4, a guide block 12 is fixedly connected to one side of the support block 11, a cylinder 13 is fixedly connected to one side of the box body 1, a connecting block 14 is fixedly connected to the output end of the cylinder 13, the outer side of the connecting block 14 is slidably connected to the inner cavity of the feed port 2, a guide frame 15 is fixedly connected to one side of the connecting block 14, the guide block 12 can slide inside the guide frame 15, a liquid storage cavity 16 is provided inside the feed port 2, and a drain pipe 17 is provided on one side of the feed port 2. After the lithium hexafluorophosphate crystallizes, the solid The liquid mixture is poured into the feed port 2, the solid-liquid mixture can be separated by the screening plate 4, the liquid flows into the liquid storage chamber 16, the liquid is discharged through the drain pipe 17, and the solid remains on the top of the screening plate 4 to obtain wet lithium hexafluorophosphate crystals, and the cylinder 13 is started to push the connecting block 14 to slide inside the box 1, driving the guide frame 15 to move, and the guide frame 15 pulls the guide block 12 to slide, so that the support block 11 drives the screening plate 4 to rotate, so that the screening plate 4 pours the wet lithium hexafluorophosphate crystals on the top onto the filter plate 7.

[0026] refer to Figure 2 and Figure 3 As shown, the driving mechanism 9 includes a motor 91 fixed to the inner wall of the driving box 10, the output end of the motor 91 is fixedly connected to a threaded rod 92, the outer side of the threaded rod 92 is threadedly connected to a threaded block 93, the outer side of the threaded block 93 is slidably connected to the inner cavity of the box body 1, one side of the threaded block 93 is fixedly connected to one side of the scraper 8, the motor 91 is started to drive the threaded rod 92 to rotate, so that the threaded block 93 drives the scraper 8 to move, and the scraper 8 can push out the purified lithium hexafluorophosphate product on the filter plate 7, and two sets of fans 18 are arranged at the bottom of the inner cavity of the box body 1. A temperature sensor 19 is provided, the heating rod 23 is started for heating, and the fan 18 is started to blow the hot air upwards, so that the hot air inside the box 1 is more uniform, thereby improving the effect of heating and drying the wet lithium hexafluorophosphate crystals. A first feed pipe 20 and a second feed pipe 21 are respectively provided on the top of the box 1. High-purity nitrogen can be introduced into the box 1 through the first feed pipe 20, and phosphorus pentafluoride gas can be introduced into the box 1 through the second feed pipe 21. A sealing cover 22 is provided on the top of the first feed pipe 20 and the second feed pipe 21, and a sealing door 24 is provided on one side of the box 1.

[0027] Working principle: When the device is in use, after the lithium hexafluorophosphate crystallizes, the solid-liquid mixture is poured into the feed port 2, the solid-liquid mixture can be separated through the screening plate 4, the liquid flows into the liquid storage chamber 16, the liquid is discharged through the drain pipe 17, and the solid remains on the top of the screening plate 4 to obtain wet lithium hexafluorophosphate crystals. The cylinder 13 is started to push the connecting block 14 to slide inside the box 1, driving the guide frame 15 to move, and the guide frame 15 pulls the guide block 12 to slide, so that the support block 11 drives the screening plate 4 to rotate, so that the screening plate 4 pours the wet lithium hexafluorophosphate crystals on the top onto the filter plate 7, and the high-purity nitrogen can be introduced into the box 1 through the first feed pipe 20, and the second feed pipe 21 can be used to Phosphorus pentafluoride gas is introduced into the box 1. First, high-purity nitrogen is introduced to drive out the air in the box 1. Then, the nitrogen flow rate is reduced, and phosphorus pentafluoride gas is introduced to start heating and temperature rise. Then, the heating rod 23 is started for heating, and the fan 18 is started to blow the hot air upward to make the hot air in the box 1 more uniform, thereby improving the effect of heating and drying the wet lithium hexafluorophosphate crystals. The heating temperature is strictly controlled to make the upper limit of the temperature lower than the decomposition temperature of lithium hexafluorophosphate. After the temperature is raised to the drying temperature, the temperature and the nitrogen and phosphorus pentafluoride gas flows are maintained for drying. After drying for a certain period of time, the heating is turned off, the introduction of phosphorus pentafluoride gas is stopped, and the high-purity nitrogen flow rate is increased. After a certain period of time, the drying is completed to obtain a purified lithium hexafluorophosphate product.

[0028] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0029] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A lithium hexafluorophosphate crystallization separation purifier, comprising a housing (1), characterized in that: Also includes: A feed inlet (2) is arranged on one side of the box body (1), a sealing plate (3) is arranged on the top of the feed inlet (2), a sieve plate (4) for separating a solid-liquid mixture is rotatably connected to the inner wall of the feed inlet (2), and a baffle (5) for preventing crystals from falling is fixed on the top of the sieve plate (4); A mounting frame (6) is fixed to the inner wall of a box body (1), a filter plate (7) is slidably connected to the inner wall of the mounting frame (6), a scraper (8) is arranged on the top of the filter plate (7) for facilitating the discharge of lithium hexafluorophosphate products, a drive box (10) is arranged on one side of the box body (1), a drive mechanism (9) is arranged inside the drive box (10) for driving the scraper (8) to move, and a heating rod (23) is arranged on the inner wall of the box body (1) for heating lithium hexafluorophosphate crystals.

2. A lithium hexafluorophosphate crystallization separation purifier according to claim 1, characterized in that: A support block (11) is fixedly connected to the top of the screening plate (4), and a guide block (12) is fixedly connected to one side of the support block (11).

3. A lithium hexafluorophosphate crystallization separation purifier according to claim 2, characterized in that: A cylinder (13) is fixedly connected to one side of the box body (1), a connecting block (14) is fixedly connected to the output end of the cylinder (13), and a guide frame (15) is fixedly connected to one side of the connecting block (14).

4. A lithium hexafluorophosphate crystallization separation purifier according to claim 1, characterized in that: A liquid storage cavity (16) is provided inside the feed port (2), and a liquid discharge pipe (17) is provided on one side of the feed port (2).

5. A lithium hexafluorophosphate crystallization separation purifier according to claim 1, characterized in that: The driving mechanism (9) comprises a motor (91) fixed to the inner wall of the driving box (10); the output end of the motor (91) is fixedly connected to a threaded rod (92); and the outer side of the threaded rod (92) is threadedly connected to a threaded block (93).

6. A lithium hexafluorophosphate crystallization separation purifier according to claim 1, characterized in that: Two groups of fans (18) are arranged at the bottom of the inner cavity of the box body (1), and a temperature sensor (19) is arranged at the bottom of the inner cavity of the box body (1).

7. A lithium hexafluorophosphate crystallization separation purifier according to claim 1, characterized in that: A first feed pipe (20) and a second feed pipe (21) are respectively arranged on the top of the box body (1), a sealing cover (22) is arranged on the top of each of the first feed pipe (20) and the second feed pipe (21), and a sealing door (24) is arranged on one side of the box body (1).

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