Device for synthesizing anhydrous lithium iodide

Abstract

The utility model belongs to the technical field of lithium batteries, and particularly relates to a device for synthesizing anhydrous lithium iodide. Comprising a tubular reactor, a material processing tank and a vacuum dryer, one end of the tubular reactor is provided with a feed port, and the other end is provided with a discharge port; the material treatment tank is connected with the discharge port through a material flowing pipe, a filter membrane is detachably mounted in the material treatment tank, the top of the material treatment tank is connected with a feeder through a feeding pipe, and a first valve is arranged on the feeding pipe; and the vacuum dryer is connected to the bottom of the material treatment tank through a material outlet pipe. By adopting the tubular reactor, the reaction efficiency is effectively improved, and the tubular reactor has the characteristic of small backmixing, so that the volume efficiency (unit volume production capacity) is high, the reaction efficiency of lithium hydroxide and hydrogen iodide is accelerated, the problem of non-uniform concentration of a reaction system in the industrial production process of lithium iodide is avoided, and the product quality is improved. And meanwhile, the production efficiency of anhydrous lithium iodide is improved.

Description

Technical Field

[0001] This invention belongs to the field of lithium battery technology, specifically an apparatus for synthesizing anhydrous lithium iodide. Background Technology

[0002] As an electrolyte in lithium batteries, lithium iodide requires very high purity, especially with strict control over its moisture and iodine content. Currently, the most common industrial synthesis method for lithium iodide involves reacting lithium carbonate or lithium hydroxide with hydroiodic acid. This method produces no waste, but the resulting product is lithium iodide trihydrate. The dehydration process in this method lacks solvent or gas protection; if air enters the disperser at high temperatures, the product is easily oxidized and deteriorated. Furthermore, the acid-base neutralization reaction is too vigorous, leading to uneven concentration in the reaction system during industrial production. Other methods for producing anhydrous lithium iodide include the organic solvent method and the two-stage pump high-vacuum method. The organic solvent method dissolves lithium iodide containing crystal water in several times its volume of organic solvent, utilizing the principle of water forming an azeotropic compound with the organic solvent. The water content of the lithium iodide is carried away during the evaporation of the organic solvent. The biggest drawback of this method is the high cost and environmental impact due to the large amount of organic solvent required. The two-stage pump high-vacuum method involves adding an oil diffusion pump or molecular pump to a rotary vane vacuum pump, resulting in complex equipment that cannot be used for large-scale industrial production. Another method is the hydrogen iodide atmosphere protection method, but this method is difficult to operate and requires highly sophisticated equipment. Utility Model Content

[0003] To address the problems mentioned above, this invention provides an apparatus for synthesizing anhydrous lithium iodide. This apparatus employs a tubular reactor, which accelerates the reaction efficiency of the two raw materials, iodine hydroxide and hydrogen iodide, and avoids the problem of uneven concentration in the lithium iodide production reaction system.

[0004] The present invention adopts the following technical solution:

[0005] An apparatus for synthesizing anhydrous lithium iodide, comprising:

[0006] A tubular reactor, with a feed inlet at one end and a discharge outlet at the other end;

[0007] The material handling tank is connected to the discharge port through a material flow pipe. A filter membrane is removably installed inside the material handling tank. A feeder is connected to the top of the material handling tank through a feeding pipe, and a first valve is installed on the feeding pipe.

[0008] The vacuum dryer is connected to the bottom of the material handling tank via a material outlet pipe.

[0009] Furthermore, the tubular reactor includes a material reaction tube arranged in an S-shape and multiple cooling water sleeves fitted on the material reaction tube. The multiple cooling water sleeves are interconnected through a cooling water connecting pipe. The water flow direction in the multiple cooling water sleeves is consistent with the material flow direction in the tubular reactor. The inlet and outlet are both located on the material reaction tube. The inlet of the cooling water sleeve is close to the inlet, and the outlet of the cooling water sleeve is close to the outlet.

[0010] Furthermore, a quick-opening valve is installed above the filter membrane inside the material processing tank. The quick-opening valve divides the space inside the material processing tank into an upper space and a lower space. The upper space is for pH value adjustment of the material, and the lower space is for filtration of the material.

[0011] Furthermore, a buffer element is installed inside the material handling tank between the quick-opening valve and the filter membrane. The buffer element has a conical structure and a material passage hole.

[0012] Furthermore, the location where the filter membrane is installed inside the material handling tank is provided with a stepped structure, and the filter membrane is detachably fixed to the stepped structure.

[0013] Furthermore, the filter membrane is an oil film with a pore size of 0.3-0.6 micrometers.

[0014] Furthermore, a second valve is installed on the material flow pipe, and a ball valve is installed on the material outlet pipe.

[0015] Furthermore, the inner wall of the material handling tank is lined with a polypropylene coating.

[0016] Furthermore, the inner wall of the vacuum dryer is lined with a titanium alloy coating.

[0017] Furthermore, the total length of the tubular reactor is 6-12 meters.

[0018] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0019] (1) The device of this utility model includes a tubular reactor, a material processing tank and a vacuum dryer connected in sequence. A 13% lithium hydroxide aqueous solution and 57% hydroiodic acid are introduced into the tubular reactor through the feed port to react. After acid-base neutralization reaction and cooling with circulating water, a lithium iodide aqueous solution is obtained. The lithium iodide aqueous solution flows out from the discharge port of the tubular reactor and flows into the material processing tank through the material flow pipe. The pH of the lithium iodide aqueous solution is then adjusted to about 7 by a feeder. After that, the lithium iodide aqueous solution is filtered through a filter membrane and flows into the vacuum dryer. It is dried at 150°C for 24 hours to obtain anhydrous lithium iodide product. The entire process of lithium iodide production is isolated from air, which reduces material exposure and improves product quality. At the same time, the device has a simple structure, is easy to operate, and is suitable for industrial production.

[0020] (2) The tubular reactor of this utility model includes a material reaction tube arranged in an S-shape and multiple cooling water sleeves fitted on the material reaction tube. The multiple cooling water sleeves are connected in sequence through a cooling water connecting pipe. The water flow direction in the multiple cooling water sleeves is consistent with the material flow direction in the tubular reactor. The cooling water sleeves are set around the material reaction tube. The cooling water circulating water at 0℃~15℃ flows in the cooling water sleeves to avoid the phenomenon of rapid increase in system temperature due to acid-base neutralization and to avoid product decomposition. At the same time, the cooling water temperature is set above 0℃ to avoid temperature transition and decrease in reaction rate.

[0021] (3) The device of this utility model has a buffer component located between the quick-opening valve and the filter membrane in the material processing tank. The buffer component has a conical structure. Before the lithium iodide aqueous solution flows from the upper space to the filter membrane in the lower space, it is buffered and decelerated on the buffer component to avoid excessive impact on the filter membrane and extend the service life of the filter membrane. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 An overall structural diagram of an apparatus for synthesizing anhydrous lithium iodide provided in an embodiment of this application;

[0024] Figure 2 This is a structural diagram of a material handling tank provided in an embodiment of this application;

[0025] Figure 3 This is a diagram showing the open state of a quick-opening valve according to an embodiment of this application;

[0026] Wherein: 1-Tube reactor, 11-Inlet, 12-Outlet, 13-Material reaction pipe, 14-Cooling water jacket, 141-Water inlet, 142-Water outlet, 15-Cooling water connecting pipe, 2-Material processing tank, 21-Filter membrane, 22-Quick-opening valve, 221-Baffle, 23-Upper space, 24-Lower space, 25-Buffer, 26-Step structure, 3-Vacuum dryer, 4-Material flow pipe, 41-Second valve, 5-Feeding pipe, 51-First valve, 6-Feeder, 7-Material outlet pipe, 71-Ball valve. Detailed Implementation

[0027] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0028] The following is in conjunction with the appendix Figure 1 To be continued Figure 3 The present invention will be described in detail with specific embodiments.

[0029] See Figures 1 to 3 This utility model provides an apparatus for synthesizing anhydrous lithium iodide, used for producing lithium iodide, including a tubular reactor 1, a material processing tank 2, and a vacuum dryer 3. The tubular reactor 1 has an inlet 11 at one end and an outlet 12 at the other end. The material processing tank 2 is connected to the outlet 12 through a material flow pipe 4. A filter membrane 21 is removably installed inside the material processing tank 2. A feeder 6 is connected to the top of the material processing tank 2 through a feeding pipe 5, and a first valve 51 is provided on the feeding pipe 5. The vacuum dryer 3 is connected to the bottom of the material processing tank 2 through a material outlet pipe 7. The process of synthesizing lithium iodide using the apparatus of this application is as follows: First, a 3% lithium hydroxide aqueous solution and 57% hydroiodic acid are introduced into tubular reactor 1 through the inlet 11 to react. After acid-base neutralization and cooling with circulating water, a lithium iodide aqueous solution is obtained. The lithium iodide aqueous solution flows out from the outlet 12 of tubular reactor 1 and flows into the material processing tank 2 through the material flow pipe 4. Then, the pH of the lithium iodide aqueous solution is adjusted to about 7 by the feeder 6. After that, the lithium iodide aqueous solution is filtered through the filter membrane 21 and flows into the vacuum dryer 3, where it is dried at 150°C for 24 hours to obtain anhydrous lithium iodide product. The entire process of producing lithium iodide using the apparatus of this application is isolated from air, minimizing material exposure and improving product quality. At the same time, the apparatus has a simple structure, is easy to operate, and is suitable for industrial production.

[0030] In some embodiments, the tubular reactor 1 includes a material reaction tube 13 arranged in an S-shape and multiple cooling water sleeves 14 fitted onto the material reaction tube 13. The multiple cooling water sleeves 14 are interconnected through cooling water connecting pipes 15. The water flow direction in the multiple cooling water sleeves 14 is consistent with the material flow direction in the tubular reactor 1. The inlet 141 of the cooling water sleeve 14 is close to the feed inlet 11, and the outlet 142 of the cooling water sleeve 14 is close to the discharge outlet 12. For example, the material reaction tube 13 includes multiple horizontal tubes arranged side by side and an arc-shaped bend connecting two adjacent horizontal tubes. Each horizontal tube is fitted with a cooling water sleeve 14, and the annular gap between the cooling water sleeve 14 and the horizontal tube forms a cooling water space. A cooling water connecting pipe 15 is provided on the side of each arc-shaped bend. This application uses an S-shaped material reaction pipe 13 and a cooling water jacket 14 to introduce cooling circulating water at 0℃~15℃ during the acid-base neutralization process of the raw materials. This can avoid the phenomenon of a sharp rise in system temperature caused by acid-base neutralization and prevent product decomposition. At the same time, setting the cooling water temperature above 0℃ can prevent temperature over-extension and a decrease in reaction rate.

[0031] In some embodiments, a quick-opening valve 22 is also provided above the filter membrane 21 inside the material processing tank 2. The quick-opening valve 22 divides the space inside the material processing tank 2 into an upper space 23 and a lower space 24. The upper space 23 is the pH adjustment space for the material, and the lower space 24 is the filtration space for the material. Before filtration, the pH value of the lithium iodide aqueous solution is first adjusted to about 7, and then it is placed into the lower space 24 for filtration to remove insoluble substances in the solution. This application, by setting the quick-opening valve 22, can achieve simultaneous pH adjustment in the upper space 23 and material filtration in the lower space 24, thereby improving production efficiency.

[0032] See Figure 3 In a specific embodiment, the quick-opening valve 22 consists of two horizontally arranged partitions 221. After the two partitions 221 are joined together, they divide the material handling tank 2 into an upper space 23 and a lower space 24. The two partitions 221 are respectively connected to an external motor drive through a rotating shaft that passes through the material handling tank 2. The motor drives the rotating shaft to rotate the partitions 221, so that the two partitions 221 change from the joined state to the downward opening state, opening the material flow channel, and allowing the material to fall from the upper space 23 into the lower space 24 under the action of gravity.

[0033] It should be noted that when the two partitions 221 are in a mating state, a sealing barrier needs to be formed to prevent material leakage. For example, a sealing strip is used on the outer edge of the partition 221 to enhance air tightness and liquid tightness. In addition, the connection between the rotating shaft and the material handling tank also needs to be sealed to prevent material from flowing out.

[0034] Furthermore, this application does not limit the specific driving method. All driving means that can achieve the opening and sealing of the two partitions 221 are within the protection scope of this application.

[0035] In some embodiments, a buffer element 25 is also provided inside the material handling tank 2 between the quick-opening valve 22 and the filter membrane 21. The buffer element 25 has a conical structure and a material passage hole. Before the lithium iodide aqueous solution flows from the upper space to the filter membrane 21 in the lower space, it is buffered and slowed down by the buffer element 25 to avoid excessive impact on the filter membrane 21 and extend the service life of the filter membrane 21.

[0036] In some embodiments, a stepped structure 26 is provided at the location where the filter membrane 21 is installed inside the material handling tank 2, and the filter membrane 21 is detachably connected to the stepped structure 26. For example, the filter membrane 21 is connected to the stepped structure 26 by an annular mounting plate. The annular mounting plate is made of rigid material and can be directly placed on the stepped structure 26 to cooperate with the stepped structure without the need for other parts, making installation and replacement easier.

[0037] In some embodiments, the filter membrane 21 is an oil film with a pore size of 0.3-0.6 micrometers. Preferably, the pore size of the oil film is 0.45 micrometers, which can filter out almost all impurities, resulting in higher purity of lithium iodide.

[0038] Specifically, a second valve 41 is provided on the material flow pipe 4, which is used to control the volume of material entering the material processing tank 2; a ball valve 71 is provided on the material outlet pipe 7, which is used to control the volume of material entering the vacuum dryer 3.

[0039] In some embodiments, the inner wall of the material handling tank 2 is lined with a polypropylene coating. Polypropylene (PP) is a semi-crystalline thermoplastic with high impact resistance, strong mechanical properties, and resistance to various organic solvents and acid and alkali corrosion. Laying it on the lining of the material handling tank can prevent it from chemically reacting with lithium iodide.

[0040] Furthermore, the inner wall of the vacuum dryer 3 is lined with a titanium alloy coating. Titanium alloy has the advantage of high temperature resistance, so temperature increases will not affect the vacuum dryer 3 itself.

[0041] In some embodiments, the diameter of the tubular reactor 1 is 10-20 mm, which effectively improves the reaction efficiency and avoids pipeline blockage in the reactor; the total length of the tubular reactor 1 is 6-12 meters, allowing the material to react fully inside.

[0042] In some embodiments, the tubular reactor 1 is made of a material that is resistant to acids, alkalis and corrosion, such as stainless steel, to further ensure product quality.

[0043] This application uses a tubular reactor, which effectively improves the reaction efficiency. The tubular reactor itself has the characteristic of low backmixing, so the volumetric efficiency (production capacity per unit volume) is high, which accelerates the reaction efficiency of lithium hydroxide and hydrogen iodide, avoids the problem of uneven concentration of the reaction system of lithium iodide in the industrial production process, and improves the production efficiency of anhydrous lithium iodide.

[0044] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the substance and scope of the present invention. Various modifications made by those skilled in the art to the above embodiments after reading this specification are all within the scope of protection of the present invention.

Claims

1. An apparatus for synthesizing anhydrous lithium iodide, characterized by, The utility model relates to a kind of material processing device, including: Tubular reactor, one end of the tubular reactor is provided with feed inlet, the other end is provided with discharge port; Material processing tank, the material processing tank is connected with the discharge port by material flow pipe, detachable replacement filter membrane is installed in the material processing tank, the top of the material processing tank is connected with feeder by feeding pipe, first valve is equipped on the feeding pipe; Vacuum drying machine, the vacuum drying machine is connected to the bottom of the material processing tank by material outlet pipe.

2. The apparatus for synthesizing anhydrous lithium iodide according to claim 1, wherein The tubular reactor includes material reaction tube arranged in S-shaped structure and multiple cooling water jacket pipes sleeved on the material reaction tube, multiple cooling water jacket pipes are communicated with each other by cooling water communication pipe, water flow direction in multiple cooling water jacket pipes is consistent with material flow direction in the tubular reactor;The feed inlet and the discharge port are arranged on the material reaction tube, the water inlet of the cooling water jacket pipe is close to the feed inlet, and the water outlet of the cooling water jacket pipe is close to the discharge port.

3. The apparatus for synthesizing anhydrous lithium iodide according to claim 1, wherein The material processing tank is further provided with quick-opening valve above the filter membrane, the quick-opening valve divides the space in the material processing tank into upper space and lower space, the upper space is PH value control space of material, and the lower space is filter space of material.

4. The apparatus for synthesizing anhydrous lithium iodide according to claim 3, wherein The material processing tank is further provided with buffer between the quick-opening valve and the filter membrane, the buffer is in conical structure, and the buffer is provided with material passing hole.

5. The apparatus for synthesizing anhydrous lithium iodide according to claim 1, wherein The position of the filter membrane installed in the material processing tank is provided with step structure, and the filter membrane is detachably fixed on the step structure.

6. The apparatus for synthesizing anhydrous lithium iodide according to claim 1, wherein The filter membrane is oil membrane with pore size of 0.3-0.6 microns.

7. The apparatus for synthesizing anhydrous lithium iodide according to claim 1, wherein The material flow pipe is provided with second valve, and the material outlet pipe is provided with ball valve.

8. The apparatus for synthesizing anhydrous lithium iodide according to claim 1, wherein The inner wall of the material processing tank is lined with polypropylene coating.

9. The apparatus for synthesizing anhydrous lithium iodide according to claim 1, wherein The inner wall of the vacuum drying machine is lined with titanium alloy coating.

10. The apparatus for synthesizing anhydrous lithium iodide according to claim 1, wherein The total length of the tubular reactor is 6-12 meters.

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