Equipment for bis (2, 2-difluoroethyl) sulfite

Abstract

The utility model relates to the technical field of sulfite, in particular to equipment for bis (2, 2-difluoroethyl) sulfite, which is sequentially provided with a large tank part, a metering tank part, a preheater part, a pipeline high-pressure reactor, a pipeline heat exchanger, a pressure relief pipe part, a gas-liquid separator, a condenser, a rectifying tower, a reaction kettle, a distillation tower, a receiving tank and a finished product tank through pipelines according to the production direction. The first metering tank is connected with the superheater through the first preheater, and the superheater is connected with the pipeline high-pressure reactor; the second large tank is connected with a second preheater through a second metering tank, and the second preheater is connected with a pipeline high-pressure reactor; and the third large tank is connected with the pipeline high-pressure reactor. According to the utility model, the problems of high viscosity, instability to a negative electrode, low dissolving capacity to lithium salt, price factors and the like of the existing sulfite solvent are solved, the yield is increased, and the market competitiveness of a company is improved; the process is simple, operation is convenient, and equipment requirements are low; the reaction control is safer.

Description

Technical Field

[0001] The utility model relates to the technical field of sulfite, in particular to equipment for bis(2,2-difluoroethyl)sulfite. Background Art

[0002] Bis(2,2-difluoroethyl)sulfite molecular formula C4H6F4, CAS number: 1980053-47-1, boiling point: 184.3±40.0℃, flash point: 65.3±27.3℃, specific gravity: 1.508±0.06g / cm3, heat of vaporization: 40.3±3.0 kJ / mol, colorless liquid at room temperature, miscible with ether, acetone and ethanol.

[0003] Lithium-ion batteries are currently the most widely used electrochemical energy storage method and have been widely used in 3C digital electronic devices, new energy vehicles, energy storage base stations, aerospace and military equipment. The electrolyte is known as the "blood" of the battery. It carries important functions such as the transmission of lithium ions in the battery and the formation of solid electrolyte membranes at the interface of the positive and negative electrodes. However, during the charging and discharging process of the battery, there are side reactions between the electrolyte and the positive and negative electrodes, which will lead to the consumption of the electrolyte, the loss of active lithium, and ultimately the battery capacity decay. The side reactions between the electrolyte and the electrode will also lead to the generation of gas and heat, causing battery expansion, thermal runaway and other safety issues. By introducing functional additives into the electrolyte, a protective film (SEI film, CEI film) can be formed on the electrode surface to inhibit the occurrence of electrolyte side reactions, but there are certain limitations in improving the cycle life of the battery and reducing the interface impedance.

[0004] The sulfur atom replaces the carbonyl carbon so that the sulfur-containing additive has a lower LUMO energy level, which makes it easier to undergo electrochemical reduction reaction. The decomposition products of the sulfur-containing additive, such as Li 2 SO 3 、(CH-CH 2 -CH 2 -OSO 3 Li) 2 The passivation layer composed of the above materials has strong polarity, good adhesion to the negative electrode sheet, and is not easy to fall off, so it has a good protection effect on the negative electrode sheet. However, the addition of sulfur-containing additives will increase the impedance of the battery and reduce the ionic conductivity of the electrolyte, so the amount needs to be controlled in the electrolyte, which also limits its application in batteries. The lithium-containing additives and sulfur-containing additives work together to form organic lithium-sulfur compounds on the electrode surface, which can effectively reduce the interfacial impedance of the battery. These characteristics can be mixed with sulfur-containing additives to form complementary advantages and a synergistic effect, and avoid the shortcomings of the two additives, thereby greatly improving the performance of the battery.

[0005] In addition, some solvents with special functional groups can achieve unexpected effects after fluorination. Sulfite solvents have good chemical stability and a wide electrochemical window. The oxidation decomposition voltage of most sulfite solvents is above 5.5V. Sulfite solvents have great potential for improving the safety and high-voltage cycle performance of lithium-ion batteries. However, most sulfite solvents are solid at room temperature, or have high viscosity, instability to the negative electrode, poor solubility in lithium salts, and price factors. Introducing ether oxygen functional groups into sulfite solvents is a good way to reduce their melting point and viscosity. However, under high voltage conditions, the ether oxygen functional groups are oxidized first, which reduces the oxidation potential of the solvent. Summary of the invention

[0006] The technical problem to be solved by the utility model is to provide a device for bis(2,2-difluoroethyl)sulfite to solve the above problems.

[0007] The utility model solves the above technical problems through a technical solution: a bis(2,2-difluoroethyl)sulfite device, which is provided with a large tank part, a metering tank part, a preheater part, a pipeline high-pressure reactor, a pipeline heat exchanger, a pressure relief pipe part, a gas-liquid separator, a condenser, a rectification tower, a reaction kettle, a distillation tower, a material receiving tank and a finished product tank in sequence through a pipeline according to the production direction;

[0008] The large tank section includes a first large tank, a second large tank and a third large tank, the metering tank section includes a first metering tank and a second metering tank, the preheater section includes a first preheater and a second preheater, the first large tank is connected to the first metering tank, the first metering tank is connected to the superheater through the first preheater, and the superheater is connected to the pipeline high-pressure reactor;

[0009] The second large tank is connected to the second preheater through the second metering tank, and the second preheater is connected to the pipeline high-pressure reactor;

[0010] The third large tank is connected to the pipeline high-pressure reactor.

[0011] As a preferred technical solution of the utility model, the temperature of the high-pressure pipeline reactor is 240-270°C and the pressure is 8-12Mpa.

[0012] As a preferred technical solution of the utility model, the pressure relief pipe portion includes a primary pressure relief pipe, a secondary pressure relief pipe and a tertiary pressure relief pipe, and the primary pressure relief pipe, the secondary pressure relief pipe and the tertiary pressure relief pipe are connected to each other through pipelines.

[0013] As a preferred technical solution of the utility model, the pressure of the first-level pressure relief pipe is 7.0-8.0 MPa, the pressure of the second-level pressure relief pipe is 4.0-5.0 MPa, and the pressure of the third-level pressure relief pipe is 1.0-1.5 MPa.

[0014] As a preferred technical solution of the utility model, the pressure relief valve of the three-stage pressure relief pipe is controlled to relieve pressure and discharge material to the gas-liquid separator, so as to maintain the pressure of the gas-liquid separator at 0.2-0.3Mpa.

[0015] As a preferred technical solution of the utility model, the reactor is a glass-lined stirred reactor.

[0016] As a preferred technical solution of the utility model, the volume of the glass-lined stirred reactor is 4-8 cubic meters.

[0017] Since the utility model adopts such a structure, it has the following beneficial effects:

[0018] 1. The utility model solves the problems of the existing sulfite solvents, such as high viscosity, instability to negative electrodes, weak dissolution ability for lithium salts, and price factors, thereby increasing production and improving the company's market competitiveness;

[0019] 2. The utility model has simple process, easy operation, low equipment requirements and safer reaction control. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a schematic diagram of the equipment connection for bis(2,2-difluoroethyl)sulfite. DETAILED DESCRIPTION

[0021] The utility model is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 As shown, the utility model is a bis(2,2-difluoroethyl)sulfite equipment, which is provided with a large tank part, a metering tank part, a preheater part, a pipeline high-pressure reactor, a pipeline heat exchanger, a pressure relief pipe part, a gas-liquid separator, a condenser, a rectification tower, a reaction kettle, a distillation tower, a material receiving tank and a finished product tank in sequence through the pipeline according to the production direction;

[0023] The large tank section includes a first large tank, a second large tank and a third large tank, the metering tank section includes a first metering tank and a second metering tank, the preheater section includes a first preheater and a second preheater, the first large tank is connected to the first metering tank, the first metering tank is connected to the superheater through the first preheater, and the superheater is connected to the pipeline high-pressure reactor;

[0024] The second large tank is connected to the second preheater through the second metering tank, and the second preheater is connected to the pipeline high-pressure reactor;

[0025] The third large tank is connected to the pipeline high-pressure reactor. The large tank part, the metering tank part, the preheater part, the pipeline high-pressure reactor, the pipeline heat exchanger, the pressure relief pipe part, the gas-liquid separator, the condenser, the rectification tower, the reactor, the distillation tower, the receiving tank and the finished product tank can effectively solve the problems of the existing sulfite solvents such as high viscosity, instability to the negative electrode, weak solubility of lithium salts and price factors, and increase the output.

[0026] In the present invention, the temperature of the high-pressure pipeline reactor is 240-270° C. and the pressure is 8-12 MPa. The temperature and pressure are set according to actual production needs to meet the optimal output requirements.

[0027] Further, the utility model provides that the pressure relief pipe portion includes a primary pressure relief pipe, a secondary pressure relief pipe and a tertiary pressure relief pipe, and the primary pressure relief pipe, the secondary pressure relief pipe and the tertiary pressure relief pipe are connected to each other through pipelines.

[0028] The utility model further provides that the pressure of the first-stage pressure relief pipe is 7.0-8.0Mpa, the pressure of the second-stage pressure relief pipe is 4.0-5.0Mpa, and the pressure of the third-stage pressure relief pipe is 1.0-1.5Mpa. The pressure relief valve of the third-stage pressure relief pipe is controlled to discharge the pressure to the gas-liquid separator, and the pressure of the gas-liquid separator is maintained at 0.2-0.3Mpa. The pressure is set according to actual production needs to meet the optimal output requirements.

[0029] Furthermore, the reactor of the utility model is a glass-lined stirring reactor.

[0030] Furthermore, in the utility model, the volume of the glass-lined stirred reactor is 4-8 cubic meters.

[0031] The process for producing bis(2,2-difluoroethyl)sulfite of the utility model is:

[0032] CHCl=CCl 2 + HCl → CHCl 2 CHCl 2

[0033] CHCl 2 CHCl 2 → CHCl=CHCl + Cl 2

[0034] CHCl = CHCl + 2HF → CHF 2 CH 2 Cl + HCl

[0035] CHF 2 CH 2 Cl + CH 3-COOK + H 2 O → CHF 2 CH 2 OH + CH 3 COOH + KCl

[0036] CH 3 COOH + KOH → CH 3 COOK + H 2 O

[0037] 2CHF 2 CH 2 OH + SOCl 2 → CHF 2 CH 2 O-SO-OCH 2 CHF 2 + 2HCl

[0038] The potassium acetate aqueous solution in the first large tank is sent out by a dedicated first metering pump, heated by a first preheater and a superheater, and enters a pipeline high-pressure reactor; 1,1-difluoro-2-chloroethane in the second large tank is sent out by a dedicated second metering pump, preheated by a second preheater, mixed with the superheated potassium acetate aqueous solution, and enters a high-pressure pipeline reactor to react at a temperature of 240-270°C and a pressure of 8-12Mpa, and the materials after the reaction enter a pipeline heat exchanger for heat exchange; the reaction pressure of the high-pressure pipeline reactor and the pipeline heat exchanger is maintained, and the pressure is gradually released and discharged to the three-stage pressure relief pipe; the pressure of the first-stage pressure relief pipe is controlled at 7.0-8.0Mpa, the pressure of the second-stage pressure relief pipe is controlled at 4.0-5.0Mpa, and the pressure of the third-stage pressure relief pipe is controlled at 1.0-1.5Mpa. The pressure relief valve is controlled to release the pressure to the gas-liquid separator, and the pressure of the gas-liquid separator is maintained at 0.2-0.3Mpa, so that the 2,2-difluoroethanol generated by the reaction is discharged from the upper part of the gas-liquid separator in the form of gas phase, and then cooled and collected in the condenser. The collected 2,2-difluoroethanol is distilled to obtain pure 2,2-difluoroethanol. The reaction is carried out continuously.

[0039] 2,2-difluoroethanol is added to a 4-8 cubic glass-lined stirred reactor, and 99% concentration of thionyl chloride is added dropwise under stirring, and a small amount of reflux reaction is maintained. After the addition is completed, the temperature is maintained and stirred for 1 hour to obtain a bis(2,2-difluoroethyl)sulfite product, and the material is distilled and collected. The collected material is washed with water and acid, and then dried with a molecular sieve to obtain a finished bis(2,2-difluoroethyl)sulfite with a product content greater than 99.8%, a moisture content less than 100ppm, and a yield greater than 98%. During the reaction, the tail gas is absorbed with water.

[0040] The description and application of the utility model here are illustrative and are not intended to limit the scope of the utility model to the above-described embodiments. Variations and changes of the embodiments disclosed here are possible, and the actual replacement of the embodiments and the various components equivalent to those of ordinary skill in the art are well known. It should be clear to those skilled in the art that the utility model can be implemented in other forms, structures, arrangements, proportions, and with other elements, materials, and components without departing from the spirit or essential features of the utility model. Other variations and changes can be made to the embodiments disclosed here without departing from the spirit or essential features of the utility model.

Claims

1. A device for bis(2,2-difluoroethyl)sulfite, characterized in that: According to the production direction, the pipeline is provided with a large tank part, a metering tank part, a preheater part, a pipeline high-pressure reactor, a pipeline heat exchanger, a pressure relief pipe part, a gas-liquid separator, a condenser, a rectification tower, a reaction kettle, a distillation tower, a material receiving tank and a finished product tank in sequence; The large tank section includes a first large tank, a second large tank and a third large tank, the metering tank section includes a first metering tank and a second metering tank, the preheater section includes a first preheater and a second preheater, the first large tank is connected to the first metering tank, the first metering tank is connected to the superheater through the first preheater, and the superheater is connected to the pipeline high-pressure reactor; The second large tank is connected to the second preheater through the second metering tank, and the second preheater is connected to the pipeline high-pressure reactor; The third large tank is connected to the pipeline high-pressure reactor.

2. The device for bis(2,2-difluoroethyl)sulfite according to claim 1, characterized in that: The temperature of the pipeline high-pressure reactor is 240-270° C. and the pressure is 8-12 MPa.

3. The device for bis(2,2-difluoroethyl)sulfite according to claim 1, characterized in that: The pressure relief pipe section includes a primary pressure relief pipe, a secondary pressure relief pipe and a tertiary pressure relief pipe, and the primary pressure relief pipe, the secondary pressure relief pipe and the tertiary pressure relief pipe are connected to each other through pipelines.

4. The device for bis(2,2-difluoroethyl)sulfite according to claim 3, characterized in that: The pressure of the first-level pressure relief pipe is 7.0-8.0 MPa, the pressure of the second-level pressure relief pipe is 4.0-5.0 MPa, and the pressure of the third-level pressure relief pipe is 1.0-1.5 MPa.

5. The device for bis(2,2-difluoroethyl)sulfite according to claim 4, characterized in that: The pressure relief valve of the three-stage pressure relief pipe is controlled to release pressure and discharge material to the gas-liquid separator, and the pressure of the gas-liquid separator is maintained at 0.2-0.3Mpa.

6. The device for bis(2,2-difluoroethyl)sulfite according to claim 1, characterized in that: The reactor is a glass-lined stirred reactor.

7. The device for bis(2,2-difluoroethyl)sulfite according to claim 6, characterized in that: The volume of the glass-lined stirred reactor is 4-8 cubic meters.

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