Constant-temperature oxidation reactor for ethylene sulfite
By designing a double-layer reactor and a condenser reflux system, the temperature control problem in the synthesis of vinyl sulfate was solved, achieving efficient synthesis of vinyl sulfate and improving product yield and selectivity.
Patent Information
- Application Number
- CN202423249238.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-12-27
AI Technical Summary
In the current synthesis of vinyl sulfate, the oxidation catalysis reaction is an exothermic process, which leads to incomplete reaction, low product yield, poor selectivity, and decomposition of raw materials and products at high temperatures, making it difficult to control the heat of reaction.
A double-layer reactor with inner and outer walls is designed, with a heat transfer medium flowing between the inner and outer walls to maintain a constant temperature. Combined with stirring blades and a condenser for reflux, the reaction temperature is controlled at 30°C. A titanium-silicon molecular sieve catalyst and a constant-pressure dropping funnel are used to add the oxidant dropwise to ensure stable reaction.
High conversion, high yield and high selectivity were achieved in the synthesis of vinyl sulfate. The reaction stability was maintained and temperature fluctuations were reduced by temperature control and frequency setting of the stirring blades.
Smart Images
Figure CN223530425U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a reaction device for lithium battery electrolyte additives, and particularly to a constant temperature oxidation reactor for vinyl sulfite. Background Technology
[0002] Ethylene sulfate (DTD), as a novel electrolyte additive for lithium-ion batteries, primarily functions to suppress the decline in initial battery capacity, increase initial discharge capacity, reduce battery expansion after high-temperature storage, and improve battery charge-discharge performance and cycle life. With the market's increasing demands for lithium battery energy performance, the research and development of lithium-ion battery electrolytes and functional additives has attracted significant attention.
[0003] Currently, the main methods for synthesizing vinyl sulfate include acylation, substitution, addition, dioxane synthesis, and oxidation. Researching efficient and environmentally friendly synthetic routes for vinyl sulfate has significant commercial value. Therefore, catalytic oxidation is currently the most ideal method for synthesizing vinyl sulfate and is more suitable for industrial production. Using titanium silicate molecular sieve (TS-1) as a catalyst and hydrogen peroxide as an oxidant, vinyl sulfite is catalytically oxidized to vinyl sulfate. This reaction process is characterized by mild reaction conditions, recyclable reaction solvents, and regenerable molecular sieves, significantly reducing production costs.
[0004] However, this oxidative catalytic reaction is exothermic, and the raw materials and products decompose at high temperatures, leading to incomplete reaction, low product yield, and poor selectivity. Therefore, controlling the reaction rate and removing the heat from the reaction zone promptly are key factors in ensuring high product yield. Utility Model Content
[0005] The purpose of this invention is to address the aforementioned deficiencies in the existing technology by providing a constant-temperature oxidation reactor for vinyl sulfite, which maintains the reaction temperature at a constant low temperature, thus facilitating the forward reaction and ensuring that the reaction has the characteristics of high conversion rate, high yield, and high selectivity.
[0006] To achieve the above objectives, this utility model provides a constant-temperature oxidation reactor for vinyl sulfite, comprising a double-layered reactor with an inner wall and an outer wall. The outer wall has a support on its side, and a space is left between the inner and outer walls for dynamic circulation of the heat medium. The upper part of the reactor is provided with an upper head, and a stirring shaft is connected to the center of the upper head. The stirring shaft is provided with stirring blades. A motor is drivenly connected to the stirring shaft above the upper head. The upper head is also provided with a condenser and a constant-pressure dripping funnel. The bottom of the condenser is provided with a reflux port, which is connected to the internal space of the reactor. The liquid outlet pipe at the bottom of the constant-pressure dripping funnel is connected to the internal space of the reactor. The lower part of the reactor is provided with a discharge port.
[0007] This device is used for the catalytic oxidation of vinyl sulfite to vinyl sulfate. During operation, a certain proportion of titanium silicate molecular sieve (TS-1) as a catalyst, dichloromethane as a reaction solvent, and vinyl sulfite as the reaction raw material are added to the reactor. A certain amount of hydrogen peroxide as an oxidant is weighed and transferred into a constant-pressure dropping funnel. The dropping rate is controlled as the reaction liquid is added, and the mixture is thoroughly mixed. A heat transfer medium flowing between the inner and outer walls maintains a constant temperature inside the reactor. A motor drives the stirring blades to rotate, ensuring thorough mixing of the raw materials within the reactor. The stirring frequency is set to a constant value to maintain a stable reaction state. The reaction conditions are: temperature 30℃, time 4 hours, and the amount of TS-1 molecular sieve added is 1.3%–2.8% of the total mass of the raw materials. The gaseous material distilled during the reaction is condensed by a condenser and then returned to the reactor, which also removes some of the reaction heat. Compared with existing technologies, the advantages of this invention are: the reaction is easier to control, the reaction temperature can be maintained at a constant low temperature, which is more conducive to the forward reaction and ensures high conversion rate, high yield, and high selectivity.
[0008] Furthermore, the condenser includes an inlet and an outlet connected to the inner cavity of the condenser. A spiral condenser tube is installed inside the condenser, with its bottom connected to a reflux port and its upper end sealed. Through the long flow channel of the spiral condenser tube, heat exchange is thorough, allowing the evaporated hydrogen peroxide to be fully condensed and refluxed.
[0009] Furthermore, the constant-pressure dropping funnel includes an upper chamber and a lower chamber. The lower chamber is directly connected to the inner cavity of the reactor. A control valve is provided between the upper and lower chambers. The upper inlet of the control valve is connected to the upper chamber, and the lower part of the control valve is connected to an outlet pipe. The outlet pipe passes through the lower chamber and extends into the inner cavity of the reactor. A balance pipe is also connected between the upper part of the upper chamber and the lower chamber. When hydrogen peroxide is added, the upper end of the constant-pressure dropping funnel is closed, and the balance pipe can balance the pressure between the upper and lower chambers, allowing hydrogen peroxide to be added normally. The amount of hydrogen peroxide added can be adjusted by the control valve to ensure that the reaction temperature is controlled at a relatively low temperature.
[0010] To further enhance heat exchange, the inner wall of the reactor is provided with at least one wavy pleat. Furthermore, there are three wavy pleats, with the middle one roughly aligned with the horizontal position of the stirring blades. The wavy pleats alter the space between the inner and outer walls, allowing for greater storage of the heat transfer medium for heat exchange, thus enabling the reaction temperature to be controlled at a relatively stable level with minimal temperature fluctuations. In addition, the wavy pleats also increase the heat transfer area, making temperature control more convenient.
[0011] Furthermore, the bottom of the reactor is connected to a discharge pipe, the discharge port is inclinedly connected to the side of the discharge pipe, and the bottom of the discharge pipe is provided with an air vent.
[0012] Furthermore, a heat transfer medium inlet and outlet are provided on the lower outer wall of the reactor. To ensure the smooth progress of the reaction, an electric heater is installed between the inner and outer walls at the bottom of the reactor. Although the reaction is exothermic, the exothermic process is not intense, and heating is still necessary when needed.
[0013] Furthermore, a temperature sensor is provided on the upper end cap. This is achieved through a heating device with automatic program temperature control. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of this utility model.
[0015] Figure 2 for Figure 1 A schematic diagram of the constant pressure dropping funnel section in the diagram.
[0016] In the diagram, 1 is the heat medium inlet, 2 is the electric heater, 3 is the corrugated pleats, 4 is the outer wall, 5 is the inner wall, 6 is the support, 7 is the upper end cap, 8 is the reflux port, 9 is the water outlet, 10 is the condenser, 11 is the water inlet, 12 is the motor, 13 is the constant pressure dripping funnel, 13a is the upper cavity, 13b is the lower cavity, 13c is the liquid outlet pipe, 13d is the balance pipe, 14 is the control valve, 15 is the temperature sensor, 16 is the stirring shaft, 17 is the stirring blade, 18 is the heat medium outlet, 19 is the discharge pipe, 20 is the vent, 21 is the discharge port, and 22 is the spiral condenser tube. Detailed Implementation
[0017] The present invention will be further described below with reference to the accompanying drawings:
[0018] like Figure 1-2 As shown, a isothermal oxidation reactor for vinyl sulfite includes a double-layered reactor with an inner wall 5 and an outer wall 4. A support 6 is provided on the side of the outer wall 4. A space is left between the inner wall 5 and the outer wall 4 for dynamic circulation of the heat medium. An upper head 7 is provided at the top of the reactor. A stirring shaft 16 is connected to the center of the upper head 7. Stirring blades 17 are provided on the stirring shaft 16. A motor 12 is connected to the upper head 7 and the stirring shaft 16. A condenser 10 and a constant pressure dripping funnel 13 are also provided on the upper head 7. A reflux port 8 is provided at the bottom of the condenser 10, which is connected to the internal space of the reactor. The liquid outlet pipe 13c at the bottom of the constant pressure dripping funnel 13 is connected to the internal space of the reactor. A discharge port 21 is provided at the bottom of the reactor.
[0019] Furthermore, the condenser 10 includes an inlet 11 and an outlet 9 connected to the inner cavity of the condenser 10. A spiral condenser tube 22 is provided inside the condenser 10. The bottom of the spiral condenser tube 22 is connected to the reflux port 8, and the upper end of the spiral condenser tube 22 is closed. Through the spiral condenser tube 22, with its long flow channel and sufficient heat exchange, the evaporated hydrogen peroxide can be fully condensed and refluxed.
[0020] Furthermore, the constant-pressure dropping funnel 13 includes an upper cavity 13a and a lower cavity 13b. The lower cavity 13b is directly connected to the inner cavity of the reactor. A control valve 14 is provided between the upper cavity 13a and the lower cavity 13b. The upper inlet of the control valve 14 is connected to the upper cavity 13a, and the lower part of the control valve 14 is connected to an outlet pipe 13c. The outlet pipe 13c passes through the lower cavity 13b and extends into the inner cavity of the reactor. A balance pipe 13d is also connected between the upper part of the upper cavity 13a and the lower cavity 13b. The amount of hydrogen peroxide added can be adjusted by the control valve 14 to ensure that the reaction temperature is controlled at a relatively low temperature.
[0021] To further enhance heat exchange, the inner wall 5 of the reactor is provided with at least one wavy pleat 3. Furthermore, there are three wavy pleats 3, with the middle one roughly aligned horizontally with the stirring blade 17. The wavy pleats 3 alter the space between the inner wall 5 and the outer wall 4, allowing for greater storage of the heat transfer medium for heat exchange, thus enabling the reaction temperature to be controlled at a relatively stable level with minimal temperature fluctuations. In addition, the wavy pleats 3 also increase the heat transfer area, making temperature control more convenient.
[0022] Furthermore, the bottom of the reactor is connected to a discharge pipe 19, the discharge port 21 is inclinedly connected to the side of the discharge pipe 19, and the bottom of the discharge pipe 19 is provided with an air vent 20.
[0023] Furthermore, a heat transfer medium inlet 1 and a heat transfer medium outlet 18 are provided on the outer wall 4 at the bottom of the reactor. To ensure the smooth progress of the reaction, an electric heater 2 is provided between the inner wall 5 and the outer wall 4 at the bottom of the reactor. Although the reaction is exothermic, the exothermic reaction is not intense, and heating is still required if necessary.
[0024] Furthermore, a temperature sensor 15 is provided on the upper end cap 7. This is achieved through a heating device with automatic program temperature control.
[0025] This device is used for the catalytic oxidation of vinyl sulfite to vinyl sulfate. During operation, a certain proportion of titanium silicate molecular sieve (TS-1) as a catalyst, dichloromethane as a reaction solvent, and vinyl sulfite as the reaction raw material are added to the reactor. A certain amount of hydrogen peroxide as an oxidant is weighed and transferred into a constant-pressure dropping funnel 13. The reaction liquid is added at a controlled dropping rate and mixed evenly. A heat transfer medium flowing between the inner wall 5 and the outer wall 4 maintains a constant temperature inside the reactor. A motor 12 drives the stirring blades 17 to rotate, ensuring thorough mixing of the raw materials within the reactor. The stirring frequency is set to a constant value during the reaction to maintain a stable reaction state. The reaction conditions are: temperature 30℃, time 4 hours, and the amount of TS-1 molecular sieve added is 1.3% to 2.8% of the total mass of the raw materials. The gaseous material distilled during the reaction is condensed by the condenser 10 and then returned to the reactor, which also removes some of the reaction heat. The heat transfer medium flowing between the inner wall 5 and the outer wall 4 is hot pure water, preferably at a temperature of 30℃. The medium flowing into the condenser 10 is an ice-water mixture. The stirring frequency is variable frequency, preferably 60Hz. The constant pressure dropping funnel 13 has a titration rate of 5-8 ml / min, and the dropping solution is an 8%-10% hydrogen peroxide solution.
[0026] This utility model is not limited to the above embodiments. Based on the technical solutions disclosed herein, those skilled in the art can make some substitutions and modifications to some of the technical features without creative labor, and these substitutions and modifications are all within the protection scope of this utility model.
Claims
1. A isothermal oxidation reactor for vinyl sulfite, characterized in that: The reactor includes a double-layer structure with an inner wall and an outer wall. The outer wall has a support on its side, and a space is left between the inner and outer walls for dynamic circulation of the heat medium. The upper part of the reactor is equipped with an upper head, and a stirring shaft is connected to the center of the upper head. The stirring shaft is equipped with stirring blades. A motor is connected to the stirring shaft above the upper head. The upper head is also equipped with a condenser and a constant pressure dripping funnel. The bottom of the condenser is equipped with a reflux port, which is connected to the internal space of the reactor. The liquid outlet pipe at the bottom of the constant pressure dripping funnel is connected to the internal space of the reactor. The lower part of the reactor is equipped with a discharge port.
2. The isothermal oxidation reactor for vinyl sulfite according to claim 1, characterized in that: The condenser includes an inlet and an outlet connected to the inner cavity of the condenser. A spiral condenser tube is provided inside the condenser. The bottom of the spiral condenser tube is connected to the return port, and the upper end of the spiral condenser tube is closed.
3. The isothermal oxidation reactor for vinyl sulfite according to claim 1, characterized in that: The constant pressure dripping funnel includes an upper cavity and a lower cavity. The lower cavity is directly connected to the inner cavity of the reactor. A control valve is provided between the upper cavity and the lower cavity. The upper inlet of the control valve is connected to the upper cavity, and the lower part of the control valve is connected to the outlet pipe. The outlet pipe passes through the lower cavity and extends into the inner cavity of the reactor. A balance pipe is also connected between the upper part of the upper cavity and the lower cavity.
4. A isothermal oxidation reactor for vinyl sulfite according to any one of claims 1-3, characterized in that: The reactor has at least one wavy fold on its inner wall.
5. The isothermal oxidation reactor for vinyl sulfite according to claim 4, characterized in that: There are three wavy folds, with the middle one roughly aligned with the horizontal position of the stirring blade.
6. A isothermal oxidation reactor for vinyl sulfite according to any one of claims 1-3, characterized in that: The bottom of the reactor is connected to a discharge pipe, the discharge port is inclined and connected to the side of the discharge pipe, and the bottom of the discharge pipe is provided with an air vent.
7. A isothermal oxidation reactor for vinyl sulfite according to any one of claims 1-3, characterized in that: The outer wall at the bottom of the reactor is equipped with a heat medium inlet and a heat medium outlet.
8. A isothermal oxidation reactor for vinyl sulfite according to any one of claims 1-3, characterized in that: An electric heater is installed between the inner and outer walls at the bottom of the reactor.
9. A isothermal oxidation reactor for vinyl sulfite according to any one of claims 1-3, characterized in that: A temperature sensor is provided on the upper end cap.