Device suitable for preparing lithium sulfide by continuous double decomposition method

Abstract

The utility model provides a device suitable for preparing lithium sulfide by a continuous double decomposition method. The device mainly comprises a material stirring reaction kettle, a solvent storage tank, continuous solid-liquid separation equipment, continuous solvent evaporation equipment, a first condensing tower and continuous dynamic vacuum calcination equipment, the device disclosed by the utility model can smoothly realize continuous production and preparation of lithium sulfide, and is simple in operation process and free from harmful gas pollution; in the preparation process, a single solvent is used and the solvent is recycled, so that the preparation method has the advantages of energy conservation and low cost, and cross contamination of multiple solvents is avoided; in addition, during continuous production of lithium sulfide, only one-time high-temperature calcination operation is carried out, and a lithium sulfide product with high purity and small particle size is successfully prepared; the composite cathode material can be directly used for preparing a sulfide solid electrolyte and a lithium-sulfur battery. The method has high industrial application value.

Description

Technical Field

[0001] This invention belongs to the field of secondary battery technology, specifically relating to an apparatus suitable for the continuous metathesis method for preparing lithium sulfide. Background Technology

[0002] All-solid-state battery technology is considered at the forefront of next-generation battery technology, promising to solve the safety hazards posed by liquid electrolytes in traditional lithium-ion batteries while providing higher energy density. Lithium sulfide, as a solid electrolyte material in all-solid-state batteries, provides stable ion conduction channels, ensuring high efficiency and safety during charge and discharge. Furthermore, the application of lithium sulfide in metal-sulfur battery systems has demonstrated its significant potential in improving battery capacity and cycle stability.

[0003] However, the production process of lithium sulfide also faces many challenges. Currently, the main methods for synthesizing lithium sulfide include the carbothermic reduction of lithium sulfate and the solution method. Industrial production of lithium sulfide primarily employs the solid-phase method based on carbothermic reduction of lithium sulfate. While this method is mature, it is a thermodynamically non-spontaneous reaction under standard conditions, thus requiring high temperatures of 600–800°C. Further purification of the product using organic solvents and high-temperature calcination are also necessary. The carbothermic reduction of lithium sulfate process typically involves mixing lithium sulfate with a carbon source and reacting at high temperatures to produce lithium sulfide and carbon dioxide. However, this production method suffers from low capacity due to the intermittent reaction, high cost due to process complexity, and high energy consumption due to the high temperature required for the reaction. Furthermore, the carbon dioxide produced during the reaction is a greenhouse gas, adversely affecting the environment; to reduce environmental pollution, the emitted gases need to be treated, which adds further costs.

[0004] In industrial production, to improve the purity and yield of lithium sulfide, a secondary calcination treatment of the reaction products is usually required. This process not only increases the number of production steps but also further increases energy consumption. Due to these drawbacks, the traditional carbothermic reduction of lithium sulfate is difficult to meet the needs of large-scale production and also fails to meet my country's dual carbon targets, namely, carbon peaking and carbon neutrality.

[0005] Solution synthesis is another method for synthesizing lithium sulfide. It typically involves adding a lithium-containing compound (such as lithium hydride, lithium triethylborohydride, etc.) and a sulfur-containing compound (such as sulfur) to an organic solvent, where they react in the solution phase to obtain lithium sulfide. While this method can be carried out at relatively low temperatures, the expensive lithium metal or lithium-containing compounds used make large-scale industrial application difficult. Furthermore, solution synthesis is relatively inefficient, and there are certain technical challenges in handling and recovering the organic solvent.

[0006] Chinese patent CN117720071A discloses a method for obtaining lithium sulfide powder by direct chemical reaction of lithium vapor and sulfur vapor. While this method simplifies the reaction steps, the raw material lithium metal is expensive and poses a high risk of explosion. Furthermore, this method is not suitable for large-scale production due to the difficulty in scaling up the reaction.

[0007] Current methods for producing lithium sulfide still face numerous challenges, including high energy consumption, high cost, environmental pollution, and difficulty in large-scale production. Achieving efficient, low-cost, and environmentally friendly production of lithium sulfide to meet the rapid development needs of all-solid-state batteries and metal-sulfur battery systems is a pressing technical problem that needs to be solved. Utility Model Content

[0008] This invention addresses the problems in existing technologies by disclosing an apparatus suitable for the continuous metathesis method of lithium sulfide preparation. The apparatus requires only one high-temperature calcination process during lithium sulfide preparation, thus achieving low energy consumption and avoiding greenhouse gas emissions, meeting the relevant requirements of the national dual-carbon target. Furthermore, the apparatus enables solvent recovery and reuse during the production process. The prepared lithium sulfide product has small particle size and high purity, and can be directly used in the preparation of sulfide solid electrolytes and as a composite cathode material for alkali metal-sulfur batteries.

[0009] This utility model is achieved through the following technical solution:

[0010] In a first aspect, this utility model provides an apparatus suitable for the continuous metathesis method of preparing lithium sulfide; the apparatus includes:

[0011] A material stirring reactor is used to receive reactants for reaction.

[0012] A solvent storage tank is connected to the material stirring reactor and is used to supply the reaction solvent required for the reaction to the material stirring reactor;

[0013] A continuous solid-liquid separation device is connected to a material stirring reactor and is used to receive and separate the reaction liquid from the material stirring reactor.

[0014] A continuous solvent evaporation device, connected to a continuous solid-liquid separation device; used to receive liquid phase mixtures from the continuous solid-liquid separation device and evaporate the solvent;

[0015] The first condenser tower is connected between the continuous solvent evaporation equipment and the solvent storage tank. It is used to condense the evaporated solvent from the continuous solvent evaporation equipment and recover it to the solvent storage tank.

[0016] The continuous dynamic vacuum calcination equipment is connected to the continuous solvent evaporation equipment. It is used to receive the product-containing solid material from the continuous solvent evaporation equipment and perform vacuum calcination on the product-containing solid material to obtain the product.

[0017] As a further embodiment, the device also includes a product storage tank connected to a continuous dynamic vacuum calcination device for collecting products from the continuous dynamic vacuum calcination device.

[0018] As a further embodiment, the apparatus also includes a second condensation tower connected between the continuous dynamic vacuum calcination equipment and the solvent storage tank, used to condense the evaporated solvent generated during the calcination of the product-containing solid phase material in the continuous dynamic vacuum calcination equipment and recover it to the solvent storage tank.

[0019] As a further embodiment, the apparatus also includes a first solvent recovery tank; the first solvent recovery tank is connected between the first condenser and the solvent storage tank, and is used to receive solvent condensed from the first condenser and recover it to the solvent storage tank.

[0020] As a further embodiment, the apparatus also includes a second solvent storage tank; the second solvent storage tank is connected between the second condenser and the solvent storage tank, and is used to receive solvent condensed from the second condenser and recover it to the solvent storage tank.

[0021] As a further embodiment, the device also includes a refrigeration unit, which is connected to the first condensing tower and the second condensing tower respectively, and is used to provide the refrigeration function required for the condensation process of the first condensing tower and the second condensing tower.

[0022] In the device of this utility model, the methods commonly used by those skilled in the art are continued to be used. The refrigerator is connected to the cold side inlet and outlet of the first condensing tower and the second condensing tower respectively, and is used to provide the temperature required when the cooling medium circulates in the condensing tower; the hot side inlet of the first condensing tower is connected to the outlet of the continuous solvent evaporation equipment, and the hot side outlet of the first condensing tower is connected to the inlet of the first solvent recovery tank; the hot side inlet of the second condensing tower is connected to the outlet of the continuous dynamic vacuum calcination equipment, and the hot side outlet of the second condensing tower is connected to the inlet of the second solvent storage tank.

[0023] As a further embodiment, the device also includes an inert gas tank connected to a material stirring reactor, which is used to provide inert gas to the reaction system through the material stirring reactor to maintain the inertness of the reaction environment.

[0024] As a further provision, this utility model does not specifically limit the type of inert gas container in principle; as some exemplary descriptions, the inert gas container is selected from nitrogen gas container and argon gas container.

[0025] As a further embodiment, the device also includes a first vacuum pump and a second vacuum pump; the first vacuum pump is connected to the first condensing tower, and on the one hand, it works in conjunction with the inert gas tank to maintain the inert gas environment inside the entire device, and on the other hand, it provides a negative pressure environment for the condensing tower by extracting and discharging gas, maintaining the vacuum degree inside the condensing tower, thereby improving the cooling recovery rate of the condensing tower; the second vacuum pump is connected to the second condensing tower.

[0026] As a further embodiment, the device also includes a solid by-product storage tank connected to a continuous solid-liquid separation device for collecting solid by-products generated during the separation of the reaction liquid by the continuous solid-liquid separation device.

[0027] As a further embodiment, the device also includes a quality controller connected to the material stirring reactor to control the amount of reactants added to the reactor and the reaction process, thereby ensuring the stability of the reaction and the quality of the product.

[0028] As a further embodiment, the device also includes a liquid flow controller; disposed between the solvent storage tank and the material stirring reactor, for controlling the flow rate ratio of solvent added to the material stirring reactor.

[0029] As a further embodiment, the device also includes a first liquid transfer pump, a second liquid transfer pump, and a third liquid transfer pump; used to transfer liquid to the corresponding equipment. The first liquid transfer pump is connected to the solvent storage tank and the material stirring reactor, ensuring that the solvent in the solvent storage tank can be smoothly added to the material stirring reactor. The second liquid transfer pump is connected to the continuous solid-liquid separation equipment and the continuous solvent evaporation equipment, responsible for transporting the liquid phase mixture separated by the continuous solid-liquid separation equipment to the continuous solvent evaporation equipment. The third liquid transfer pump is connected to the first solvent recovery tank and the solvent storage tank, used to transport the solvent recovered and stored in the first solvent recovery tank back to the solvent storage tank, realizing the recycling of solvent.

[0030] This invention does not, in principle, impose specific limitations on the type and configuration of the solution pump. Those skilled in the art can select appropriate pump types and configurations to meet production needs based on actual production requirements and equipment conditions. For example, gear pumps, diaphragm pumps, or centrifugal pumps can be selected to adapt to the transport of different types and flow rates of liquids.

[0031] The features and beneficial effects of this utility model are as follows:

[0032] This invention enables solvent recycling during the production process, using only a single solvent and avoiding the possibility of solvent contamination. Secondly, the device allows for completely continuous operation, significantly improving production efficiency. Furthermore, by employing continuous solid-liquid separation, continuous solvent evaporation, and continuous dynamic vacuum calcination technologies, high product purity is ensured. In addition, the device avoids high-pressure reactions during preparation, achieving low energy consumption. The metathesis reaction for lithium sulfide preparation involves only one calcination and drying step, effectively preventing greenhouse gas emissions and meeting the relevant requirements of the national dual-carbon target. The continuous nature and ease of operation of this production process make it suitable for industrial continuous production. The resulting lithium sulfide product has high purity and small particle size, and can be directly used to prepare sulfide solid electrolytes and composite cathode materials for alkali metal-sulfur batteries. This provides an efficient and environmentally friendly solution for lithium sulfide production. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in this utility model, 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.

[0034] Figure 1 This is a process flow diagram of the device of this utility model;

[0035] Figure 2 This is an XRD pattern of the lithium sulfide product prepared in the embodiment of the present invention.

[0036] Figure 3 This is a SEM image of the lithium sulfide product prepared in the embodiment of the present invention.

[0037] Reference numerals:

[0038] Material stirring reactor 1, solvent storage tank 2, liquid flow controller 21, first liquid transfer pump 22, continuous solid-liquid separation equipment 3, second liquid transfer pump 31, continuous solvent evaporation equipment 4, first solvent recovery tank 5, third liquid transfer pump 51, continuous dynamic vacuum calcination equipment 6, product storage tank 7, second solvent storage tank 8, first condensing tower 9, first vacuum pump 91, second condensing tower 10, second vacuum pump 101, inert gas tank 11, solid by-product storage tank 12, quality controller 13, and refrigeration unit 14. Detailed Implementation

[0039] To facilitate understanding of this utility model, a more comprehensive description of this utility model will be provided below, along with embodiments of this utility model, but this does not limit the scope of this utility model.

[0040] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the term "comprising" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusion.

[0041] like Figure 1 As shown; the apparatus of this utility model will be described in detail using the production process of lithium sulfide as an example. The apparatus of this utility model includes:

[0042] Material stirring reactor 1 is used to receive reaction raw materials for reaction;

[0043] Solvent storage tank 2 is connected to material stirring reactor 1 and is used to supply the reaction solvent required for the reaction to material stirring reactor 1;

[0044] The continuous solid-liquid separation device 3 is connected to the material stirring reactor 1 and is used to receive and separate the reaction liquid from the reaction in the material stirring reactor 1.

[0045] A continuous solvent evaporation device 4 is connected to a continuous solid-liquid separation device 3; it is used to receive a liquid mixture from the continuous solid-liquid separation device 3 and evaporate the solvent.

[0046] The first condenser tower 9 is connected between the continuous solvent evaporation equipment 4 and the solvent storage tank 2, and is used to condense the evaporated solvent from the continuous solvent evaporation equipment 4 and recover it to the solvent storage tank 2.

[0047] The continuous dynamic vacuum calcination equipment 6 is connected to the continuous solvent evaporation equipment 4 and is used to receive the product-containing solid material from the continuous solvent evaporation equipment 4 and perform vacuum calcination on the product-containing solid material to obtain the product.

[0048] This invention's apparatus directly separates the reactants into a liquid phase mixture after the reaction, and then uses a solvent evaporation device to obtain a product-containing solid phase while simultaneously evaporating and condensing the solvent for recycling into a solvent storage tank, thus achieving solvent recycling. The product-containing solid phase is then dried under vacuum to obtain a high-purity product. This apparatus is simple and quick to operate during the production process; it also allows for solvent recycling, reducing costs and operational complexity, and preventing cross-contamination of solvents that could affect product quality. The apparatus of this invention is particularly suitable for the continuous production of lithium sulfide. Lithium sulfide is prepared through a simple metathesis reaction: Na₂S (sodium sulfide) + LiCl (lithium chloride) + alcohol solvent → Li₂S (lithium sulfide) + NaCl (sodium chloride). This preparation method avoids CO₂ emissions and meets environmental protection requirements. Furthermore, this apparatus does not involve multiple high-temperature and high-pressure operations during lithium sulfide production; instead, it achieves the preparation of small-particle-size, high-purity lithium sulfide through a single high-temperature calcination process. This allows for direct use in battery manufacturing, helping to solve the problems of gas pollution, complex processes, high costs, and the inability to produce continuously during lithium sulfide production.

[0049] As a further embodiment, the apparatus also includes a product storage tank 7, connected to a continuous dynamic vacuum calcination device 6, for collecting the product from the continuous dynamic vacuum calcination device 6. As specific examples: in the production process of lithium sulfide, the product is lithium sulfide.

[0050] As a further embodiment, the device also includes a second condensing tower 10; connected between the continuous dynamic vacuum calcination equipment 6 and the solvent storage tank 2, it is used to condense the evaporated solvent generated during the calcination of the product-containing solid phase material in the continuous dynamic vacuum calcination equipment 6 and recover it to the solvent storage tank 2. This invention adds the design of the second condensing tower 10 to fully recover and remove the solvent remaining inside the product-containing solid phase material during calcination in the continuous dynamic vacuum calcination equipment 6; ensuring product purity and facilitating direct use of the product in battery preparation, providing further support for the large-scale production and application of lithium sulfide. As some specific examples: in the lithium sulfide production process of this device, the product-containing solid phase material is a liquid-phase mixture containing lithium sulfide and a reaction solvent, which is the remaining lithium sulfide-containing solid phase material after solvent evaporation in the continuous solvent evaporation equipment 4. The second condensing tower 10 in this device can effectively recover the solvent further evaporated during the calcination process of the lithium sulfide solid phase material in the continuous dynamic vacuum calcination equipment 6, thereby improving the purity of the final lithium sulfide product.

[0051] As a further embodiment, the apparatus also includes a first solvent recovery tank 5; the first solvent recovery tank 5 is connected between the first condensation tower 9 and the solvent storage tank 2, and is used to receive the solvent condensed from the first condensation tower 9 and recover it to the solvent storage tank 2.

[0052] As a further embodiment, the apparatus also includes a second solvent storage tank 8; the second solvent storage tank 8 is connected between the second condenser tower 10 and the solvent storage tank 2, and is used to receive the solvent condensed from the second condenser tower 10 and recover it to the solvent storage tank 2.

[0053] As a further embodiment, the device also includes a chiller 14, which is connected to both the first condensing tower 9 and the second condensing tower 10, providing the necessary cooling for the condensation process. The use of the chiller 14 ensures that the condensing towers operate at lower temperatures, thereby improving the efficiency and purity of solvent recovery. In this way, the device of this invention not only improves the production efficiency of lithium sulfide but also ensures the environmental friendliness of the production process and the high quality of the product. The addition of the chiller 14 makes the entire production process more energy-efficient and effective, while reducing its environmental impact. Furthermore, the independent connection design of the chiller 14 makes the system more flexible during operation, allowing adjustments based on actual production needs and further optimizing the production process.

[0054] In the device of this utility model, the methods commonly used by those skilled in the art are continued. The refrigerator 14 is connected to the cold side inlet and outlet of the first condensing tower 9 and the second condensing tower 10 respectively, and is used to provide the temperature required for the cooling medium to circulate in the condensing tower. The hot side inlet of the first condensing tower 9 is connected to the outlet of the continuous solvent evaporation equipment 4, and the hot side outlet of the first condensing tower 9 is connected to the inlet of the first solvent recovery tank 5. The hot side inlet of the second condensing tower 10 is connected to the outlet of the continuous dynamic vacuum calcination equipment 6, and the hot side outlet of the second condensing tower 10 is connected to the inlet of the second solvent storage tank 8.

[0055] As a further embodiment, the apparatus also includes an inert gas tank 11, which is connected to the material stirring reactor 1. The inert gas tank 11 provides inert gas to the reaction system through the material stirring reactor 1, maintaining the inertness of the reaction environment. This effectively prevents the reactants from contacting oxygen in the air, thereby reducing side reactions and ensuring efficient reaction. In the continuous production of lithium sulfide using this apparatus, it helps prevent the oxidation of lithium sulfide at high temperatures, thus improving the yield and quality of lithium sulfide.

[0056] As a further provision, this utility model does not specifically limit the type of inert gas tank 11 in principle; as some exemplary descriptions, the inert gas tank 11 is selected from nitrogen gas tank and argon gas tank.

[0057] As a further embodiment, the device also includes a first vacuum pump 91 and a second vacuum pump 101; the first vacuum pump 91 is connected to the first condensing tower 9, and on the one hand, it works in conjunction with the inert gas tank 11 to maintain the inert gas environment inside the entire device, and on the other hand, it provides a negative pressure environment for the condensing tower by extracting and discharging gas, thereby maintaining the vacuum degree inside the condensing tower and improving the cooling recovery rate of the condensing tower; the second vacuum pump 101 is connected to the second condensing tower 10.

[0058] As a further embodiment, the apparatus also includes a solid by-product storage tank 12, connected to the continuous solid-liquid separation device 3, for collecting solid by-products generated during the separation of the reaction liquid in the continuous solid-liquid separation device 3. This ensures the continuity and efficiency of the production process while reducing waste generation and environmental pollution. The design of the solid by-product storage tank 12 allows for proper handling and potential reuse of the by-products, further improving resource utilization and the sustainability of the production process. As specific examples: in the production of lithium sulfide in this apparatus, the solid by-product is solid sodium chloride generated from the metathesis reaction of sodium sulfide and lithium chloride.

[0059] As a further embodiment, the device also includes a quality controller 13 connected to the material stirring reactor 1, used to control the amount of reactants added to the reactor 1 and the reaction process, ensuring the stability of the reaction and the quality of the product. As specific examples: in the production of lithium sulfide using this device, the reactants are sodium sulfide and lithium chloride, which are respectively loaded into two quality controllers 13, and fed into the material stirring reactor 1 through the quality controllers 13. This device, through the quality controllers 13, can promote the automation and precision of lithium sulfide production, significantly improving production efficiency and product quality, while reducing labor costs and operational risks.

[0060] As a further embodiment, the device also includes a liquid flow controller 21, positioned between the solvent storage tank 2 and the material stirring reactor 1, for controlling the flow rate of solvent added to the material stirring reactor 1. Precise control ensures efficient reaction while reducing solvent waste.

[0061] As a further embodiment, the device also includes a first liquid transfer pump 22, a second liquid transfer pump 31, and a third liquid transfer pump 51; used to transfer liquids to corresponding equipment. The first liquid transfer pump 22 connects to the solvent storage tank 2 and the material stirring reactor 1, ensuring that the solvent in the solvent storage tank 2 can be smoothly added to the material stirring reactor 1. The second liquid transfer pump 31 connects to the continuous solid-liquid separation device 3 and the continuous solvent evaporation device 4, responsible for transporting the liquid phase mixture separated by the continuous solid-liquid separation device 3 to the continuous solvent evaporation device 4. The third liquid transfer pump 51 connects to the first solvent recovery tank 5 and the solvent storage tank 2, used to transport the solvent recovered and stored in the first solvent recovery tank 5 back to the solvent storage tank 2, realizing the recycling of solvents. Through precise control of these transfer pumps, the continuity and stability of the entire production process can be guaranteed, while reducing material and solvent losses and improving production efficiency.

[0062] This invention does not, in principle, impose specific limitations on the type and configuration of the solution pump. Those skilled in the art can select appropriate pump types and configurations to meet production needs based on actual production requirements and equipment conditions. For example, gear pumps, diaphragm pumps, or centrifugal pumps can be selected to adapt to the transport of different types and flow rates of liquids.

[0063] The reaction solvent described in this invention can be selected from one or more solvents selected from methanol, ethanol, propanol, and isopropanol.

[0064] The specific process of the apparatus for preparing lithium sulfide by continuous metathesis based on the present invention is as follows:

[0065] Step 1: Use the first vacuum pump 91 to evacuate the entire system, and then use the inert gas tank 11 to fill the entire system to atmospheric pressure. Repeat this three times.

[0066] Step 2: Add the reaction raw materials sodium sulfide and lithium chloride from the two mass controllers 13 to the material stirring reactor 1 at a specified rate of 8±0.5 kg / min. At the same time, control the ethanol reaction solvent in the solvent storage tank 2 to be added to the material stirring reactor 1 at a specified rate of 5 L / min through the liquid flow controller 21 and the first liquid transfer pump 22 to carry out the metathesis reaction, and ensure that the reaction state is completely mixed.

[0067] Step 3: After the reaction is completed, the reaction liquid of the metathesis reaction in the material stirring reactor 1 begins to flow continuously into the continuous solid-liquid separation equipment 3 for continuous solid-liquid separation. The liquid phase mixture containing lithium sulfide and solvent enters the continuous solvent evaporation equipment 4 through the second liquid transfer pump 31 to evaporate the solvent, while the sodium chloride solid phase by-product is collected in the solid phase by-product storage tank 12.

[0068] Step 4: Turn on the refrigerator 14 and the first vacuum pump 91 and the second vacuum pump 101; the liquid mixture containing lithium sulfide and solvent is continuously evaporated in the continuous solvent evaporation equipment 4. The evaporated solvent continuously leaves from the top outlet of the continuous solvent evaporation equipment 4 and enters the first condensation tower 9 through the hot side inlet of the first condensation tower 9 for condensation. Then, it enters the first solvent recovery tank 5 through the hot side outlet of the first condensation tower 9. The solvent recovered and condensed in the first solvent recovery tank 5 is transported back to the solvent storage tank 2 by the third liquid transfer pump 51, so as to realize the recycling of solvent.

[0069] Step 5: When the continuous solvent evaporator 4 is filled more than halfway with lithium sulfide-containing solid material, the lithium sulfide-containing solid material leaves from the bottom of the continuous solvent evaporator 4 and enters the continuous dynamic vacuum calcination equipment 6. As the internal auger advances continuously, continuous calcination takes place. During the calcination process, the residual solvent in the lithium sulfide-containing solid material evaporates and passes sequentially through the outlet of the continuous dynamic vacuum calcination equipment 6 and the hot-side inlet of the second condensation tower 10, where it is condensed and recovered. Subsequently, it enters the second solvent storage tank 8 through the hot-side outlet of the second condensation tower 10, and finally is recovered into the solvent storage tank 2. At the same time, high-purity lithium sulfide product enters the product storage tank 7 from the continuous dynamic vacuum calcination equipment 6.

[0070] Step 6: The above equipment runs continuously; after the production target is achieved, the equipment is stopped and cleaned, and finally returned to a slightly positive pressure inert atmosphere protection state.

[0071] Specifically, through Figure 2 It can be seen that the lithium sulfide product prepared by this device only shows the PDF card (PDF#23-0369) of lithium sulfide in XRD, indicating that the lithium sulfide has high purity. At the same time, the particle size of lithium sulfide can be calculated by Scherrer formula.

[0072] Specifically, through Figure 3 It can be seen that the lithium sulfide product prepared by this device has a small particle size and a smooth surface, indicating that a high-purity lithium sulfide product with a small particle size has been successfully prepared by this device; it is suitable for the continuous production of lithium sulfide and has high industrial practical value.

[0073] It should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An apparatus suitable for the continuous metathesis method of preparing lithium sulfide; characterized in that, The device includes: Material stirring reactor (1), used to receive reaction raw materials for reaction; Solvent storage tank (2) is connected to material stirring reactor (1) and is used to supply the reaction solvent required for the reaction to material stirring reactor (1); A continuous solid-liquid separation device (3) is connected to a material stirring reactor (1) and is used to receive and separate the reaction liquid from the material stirring reactor (1). A continuous solvent evaporation device (4) is connected to a continuous solid-liquid separation device (3); it is used to receive the liquid phase mixture from the continuous solid-liquid separation device (3) and evaporate the solvent. The first condenser (9) is connected between the continuous solvent evaporation equipment (4) and the solvent storage tank (2) for condensing the evaporated solvent from the continuous solvent evaporation equipment (4) and recovering it to the solvent storage tank (2); The continuous dynamic vacuum calcination equipment (6) is connected to the continuous solvent evaporation equipment (4) and is used to receive the product-containing solid material from the continuous solvent evaporation equipment (4) and perform vacuum calcination on the product-containing solid material to obtain the product.

2. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device also includes a product storage tank (7) connected to a continuous dynamic vacuum calcination device (6) for collecting products from the continuous dynamic vacuum calcination device (6).

3. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device also includes a second condenser (10); connected between the continuous dynamic vacuum calcining equipment (6) and the solvent storage tank (2), for condensing the evaporated solvent generated during the calcination of the product-containing solid material in the continuous dynamic vacuum calcining equipment (6) and recovering it to the solvent storage tank (2).

4. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device further includes a first solvent recovery tank (5); the first solvent recovery tank (5) is connected between the first condenser (9) and the solvent storage tank (2) for receiving the solvent condensed from the first condenser (9) and recovering it to the solvent storage tank (2); The apparatus further includes a second solvent storage tank (8); the second solvent storage tank (8) is connected between the second condenser (10) and the solvent storage tank (2) for receiving solvent condensed from the second condenser (10) and recovering it to the solvent storage tank (2).

5. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device also includes a refrigeration unit (14), which is connected to the first condensing tower (9) and the second condensing tower (10) respectively, and is used to provide the refrigeration function required for the condensation process of the first condensing tower (9) and the second condensing tower (10).

6. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device also includes an inert gas tank (11), which is connected to the material stirring reactor (1) and is used to provide inert gas to the entire reaction system through the material stirring reactor (1).

7. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device also includes a first vacuum pump (91) and a second vacuum pump (101); the first vacuum pump (91) is connected to the first condenser (9), and the second vacuum pump (101) is connected to the second condenser (10).

8. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device also includes a solid byproduct storage tank (12), which is connected to the continuous solid-liquid separation equipment (3) and is used to collect the solid byproducts generated when the reaction liquid of the continuous solid-liquid separation equipment (3) is separated.

9. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device also includes a quality controller (13); the quality controller (13) is connected to the material stirring reactor (1) and is used to add reaction raw materials to the material stirring reactor (1); The device also includes a liquid flow controller (21); the liquid flow controller (21) is located between the solvent storage tank (2) and the material stirring reactor (1) and is used to control the amount of solvent supplied from the solvent storage tank (2) to the material stirring reactor (1).

10. The apparatus for the continuous metathesis method for preparing lithium sulfide according to claim 1, characterized in that, The device further includes a first liquid transfer pump (22), a second liquid transfer pump (31), and a third liquid transfer pump (51); the first liquid transfer pump (22) is connected between the solvent storage tank (2) and the material stirring reactor (1), the second liquid transfer pump (31) is connected between the continuous solid-liquid separation device (3) and the continuous solvent evaporation device (4), and the third liquid transfer pump (51) is connected between the first solvent recovery tank (5) and the solvent storage tank (2).

Images