Apparatus and method for synthesis of electronic grade n-vinylcarbazole in a microchannel reactor

Abstract

The application relates to a device and a method for synthesizing electronic-grade N-vinylcarbazole by using a micro-channel reactor, wherein the device for synthesizing electronic-grade N-vinylcarbazole by using a micro-channel reactor comprises a raw material liquid pretreatment system, a methylbutynol container, a nitrogen source, a micro-channel reactor and a gas-liquid separator; the raw material liquid pretreatment system and the methylbutynol container are respectively connected with the inlet of the micro-channel reactor through peristaltic pumps; the nitrogen source is simultaneously connected with the inlet of the micro-channel reactor; and the outlet of the micro-channel reactor is connected with the gas-liquid separator. By using a continuous flow micro-channel reaction system, the whole process can be monitored on line during the reaction; by using the excellent heat transfer characteristics of the micro-channel reactor, the reaction temperature can be strictly controlled, the safety risk of the high-efficiency catalyst potassium ethoxide is reduced, the risk of reaction self-polymerization heat release is reduced, and the intrinsic safety of the reaction is improved.

Description

Technical Field

[0001] This invention belongs to the field of microchannel reactors for the preparation of electronic-grade chemicals; in particular, it relates to an apparatus and method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor. Background Technology

[0002] The carbazole group in N-vinylcarbazole exhibits a planar rigidity, moderate reactivity, a large conjugated system, and strong intramolecular electron mobility, making it potentially valuable in numerous fields such as medicine, electronic materials, optical materials, and supramolecular recognition. Research on constructing artificial receptors and molecular probes based on the rigid framework structure of carbazole is also increasingly active. Therefore, the preparation of high-performance electronic materials using N-vinylcarbazole has significant application value and scientific importance.

[0003] Currently, the main methods for industrial production of vinylcarbazole both domestically and internationally include the traditional atmospheric pressure acetylene method, the high-pressure autoclave acetylene method, and the methylbutyninol substitution method, as exemplified by patents CN201410364002.9, CN201810430378.3, and CN201910652859.3. However, these methods have certain drawbacks. For example, the atmospheric pressure acetylene method results in insufficient two-phase contact, a slow reaction, and the consumption of large amounts of acetylene feedstock, leading to excessive acetylene emissions and environmental and safety risks. The pressurized acetylene method carries the risk of over-polymerization, severely impacting product quality. The methylbutyninol substitution method utilizes potassium hydroxide, which has low catalytic efficiency, an extremely low reaction rate, and a long reaction time. Furthermore, the in-situ decomposition of methylbutyninol into acetylene under atmospheric pressure does not completely dissolve in the reaction system, and the amount of methylbutyninol used is not close to the theoretical amount, making it unsuitable for industrial production.

[0004] Microchannel reactors are a novel reactor technology. Compared to traditional reactors, the heat transfer coefficient of micro-reactions can be increased from 2 kW / (m²). 2 ·K) increased to 20KW / (m 2 Microreactors (·K) possess excellent heat transfer properties that enable precise control of reaction temperatures, improve gas-liquid two-phase mass and heat transfer efficiency, enhance reaction selectivity and product quality, and make previously unattainable reaction conditions possible. Especially for fast reactions with high exothermic activity, rapidly removing the heat generated by the reaction can prevent localized overheating, reduce side reactions, and prevent runaway reactions due to heat accumulation, thus lowering the risk of reaction runaway. Microreactors themselves have the function of rapidly removing heat and have been used in various extremely exothermic reactions, such as the nitration of aromatic compounds, the hydrogenation of isobutylene, the partial oxidation of dimethyl ether, and the preparation of syngas.

[0005] This invention provides a method for synthesizing N-vinylcarbazole using a microchannel continuous reaction system. Summary of the Invention

[0006] The purpose of this invention is to provide an apparatus and method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor. By utilizing the micron-scale coupling effect of the microchannel, the gas bubbles in the heterogeneous gas-liquid fluid are effectively controlled throughout the entire process, reducing the escape of acetylene gas from the in-situ decomposition of methylbutyninol. This ensures high gas-liquid two-phase mixing efficiency during the reaction, improving the utilization rate of methylbutyninol, with optimal conditions approaching the theoretical dosage. Precise control of the reaction temperature and material ratio improves reaction selectivity and ensures the quality of electronic-grade N-vinylcarbazole. The excellent heat transfer performance of the microchannel reactor allows for strict control of the reaction temperature, reducing the safety risks of the highly efficient catalyst potassium ethoxide, reducing the risk of exothermic self-polymerization, and enhancing the inherent safety of the reaction. N-vinylcarbazole prepared using this microchannel reactor can significantly simplify the production process, improve reaction process control and safety, shorten reaction time, reduce costs, achieve continuous production, and improve the quality of N-vinylcarbazole.

[0007] To achieve the above objectives, the present invention employs the following technical solution: An apparatus for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor includes a feed liquid pretreatment system, a methylbutynol container, a nitrogen source, a microchannel reactor, and a gas-liquid separator. The feed liquid pretreatment system and the methylbutynol container are respectively connected to the inlet of the microchannel reactor via peristaltic pumps. The nitrogen source is also connected to the inlet of the microchannel reactor, and the outlet of the microchannel reactor is connected to the gas-liquid separator.

[0008] It also includes a four-way valve, which is also connected to the outlet of the microchannel reactor.

[0009] The four-way valve is equipped with a needle valve at the inlet where it connects to the microchannel reactor, a nitrogen source at the other inlet of the four-way valve, and a ball valve at one outlet of the four-way valve.

[0010] The gas-liquid separator is equipped with a ball valve at its inlet and a back pressure valve at its outlet.

[0011] A method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor includes the following steps: 1) The raw material liquid is heated through a raw material liquid pretreatment system to keep it in a fully dissolved state at all times; 2) After purging the reaction system with nitrogen, set the reaction system pressure to 0.4–1.0 MPa; 3) The feed liquid and methylbutyninol in the feed liquid pretreatment system are introduced into the microchannel reactor, so that the acetylene from the in-situ decomposition of methylbutyninol can fully achieve gas-liquid heterogeneous coupling in the micron-level channels of the microchannel reactor module. The reaction liquid is then introduced into the gas-liquid separator for gas-liquid separation to obtain the reaction liquid product. 4) The reaction process is monitored by sampling and analysis using a four-way valve connected to the outlet of the microchannel reactor.

[0012] The feed solution consists of 25%–30% carbazole and 70%–75% solvent by weight, with 3%–5% potassium ethoxide catalyst added by weight of carbazole.

[0013] The solvent is one of dimethyl sulfoxide, N-methylpyrrolidone, and isophorone.

[0014] In step 1) above, the heating temperature of the raw material liquid is 120-150℃.

[0015] In step 3) above, the feed rate of the raw material solution is 0.5–3 mL / min, and the feed rate of methylbutynol is 0.08–0.48 mL / min. The molar ratio of carbazole to methylbutynol is maintained at 1:1 to 1:1.05.

[0016] The reaction temperature of the microchannel reactor is 180–200°C, and the insulation temperature of the pipelines and gas-liquid separator in the entire reaction system is 120–150°C.

[0017] Compared with existing technologies, the beneficial effects of this invention are: 1) By precisely controlling the reaction temperature and material ratio through a microchannel reactor, the reaction selectivity is greatly improved, the risk of overpolymerization is avoided, and the quality of electronic-grade products is guaranteed.

[0018] 2) By utilizing the excellent mass transfer characteristics of microchannel reactors, gas-liquid mixing efficiency can be enhanced, reaction rate can be accelerated, utilization rate of raw material methylbutynol can be increased, cost can be reduced and environmental pollution can be reduced.

[0019] 3) Through the continuous flow microchannel reaction system, the entire reaction process can be monitored online. By utilizing the excellent heat transfer characteristics of the microchannel reactor, the reaction temperature can be strictly controlled, reducing the safety risks of the highly efficient catalyst potassium ethoxide, reducing the risk of exothermic self-polymerization, and improving the inherent safety of the reaction. Attached Figure Description

[0020] Figure 1 This is a process structure diagram of the present invention.

[0021] Figure 2 This is a liquid chromatogram of the electronic-grade N-vinylcarbazole reaction.

[0022] In the diagram: 1-Pretreatment system for raw material liquid, 2-Peristaltic pump, 3-Gas-liquid separator, 4-Methylbutynol container, 5-Nitrogen source, 6-Flow meter, 7-Microchannel reactor, 8-Ball valve, 9-Back pressure valve, 10-Needle valve, 11-Four-way valve. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The specific embodiments described herein are only for explaining the invention and are not intended to limit the invention. All reasonable variations are used to explain the content of this invention.

[0024] See Figure 1 The apparatus for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor includes a feed liquid pretreatment system 1, a methylbutynol container 4, a nitrogen source 5, a microchannel reactor 7, and a gas-liquid separator 3. The feed liquid pretreatment system 1 and the methylbutynol container 4 are respectively connected to the inlet of the microchannel reactor 7 via a peristaltic pump 2. The nitrogen source 5 is also connected to the inlet of the microchannel reactor 7. The outlet of the microchannel reactor 7 is connected to the gas-liquid separator 3.

[0025] It also includes a four-way valve 11, which is also connected to the outlet of the microchannel reactor 7.

[0026] The four-way valve 11 is connected to the microchannel reactor 7 at its inlet with a needle valve 10. The other inlet of the four-way valve 11 is connected to a nitrogen source, and the other outlet of the four-way valve 11 is equipped with a ball valve 8.

[0027] The gas-liquid separator 3 is equipped with a ball valve 8 at its inlet and a back pressure valve 9 at its outlet.

[0028] This invention utilizes the efficient mass and heat transfer characteristics of a microchannel reaction system to improve gas-liquid mixing efficiency, accelerate reaction rate, reduce the safety risks of the highly efficient catalyst potassium ethoxide, and improve the utilization efficiency of methylbutynol. Through precise control of reaction temperature and material ratio, it enhances reaction selectivity, improves product quality, and ensures the inherent safety of the reaction process. The microchannel reactor apparatus for synthesizing electronic-grade N-vinylcarbazole of this invention includes: a raw material pretreatment system 1, a peristaltic pump 2, a microchannel reactor 7 (equipped with an integrated temperature control unit), an inlet pipe, an outlet pipe, a gas-liquid separator 3 (equipped with an integrated temperature control unit), a ball valve 8, a needle valve 10, a back pressure valve 9, and a four-way valve 11. The raw material pretreatment system 1 consists of a three-necked flask and a magnetic stirring heating mantle to ensure the uniformity of mixing of raw materials and catalyst. The inlet pipe connects the raw material pretreatment system 1, the methylbutynol container 4, the peristaltic pump 2, and the microchannel reactor 7. The outlet pipe is connected to the ball valve 8, the gas-liquid separator 3, the needle valve 10, and the four-way valve 11. Both the inlet and outlet pipes are insulated with electric heating tapes, with a temperature of 120-150℃. The gas-liquid separator 3 is also insulated at a temperature of 120-150℃.

[0029] The microchannel reactor 7 consists of four modules installed in series. The modules are made of pressureless sintered silicon carbide, with dimensions of 185mm x 125mm and channel dimensions of 1.5mm x 1mm. The specific surface area is 1900 m². 2 / m 3 The temperature in the microchannel reactor 7 is controlled at 180–200℃, and the pressure is 0.4–1.0 MPa during the reaction.

[0030] A method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor includes the following steps: 1) The raw material liquid is heated by the raw material liquid pretreatment system 1 to keep the raw material liquid in a fully dissolved state at all times.

[0031] The prepared raw material solution is placed in a three-necked flask, and the magnetic stirrer and heating mantle are turned on to heat the flask, keeping the material in a completely dissolved state. The heating temperature of the raw material solution is 120-150℃.

[0032] The feed solution consists of 25-30% by weight of carbazole and 70-75% by weight of solvent, with 3-5% by weight of potassium ethoxide catalyst added.

[0033] The solvent is one of dimethyl sulfoxide, N-methylpyrrolidone, or isophorone.

[0034] 2) After purging the reaction system with nitrogen, set the reaction system pressure to 0.4–1.0 MPa.

[0035] Set ball valve 8, needle valve 10, peristaltic pump 2, back pressure valve 9, and four-way valve 11 to the fully open position. Open the nitrogen cylinder to fill the continuous microchannel reaction system with nitrogen. Purge the system with nitrogen for 5-10 minutes. Close the nitrogen cylinder. Then close back pressure valve 9, four-way valve 11, ball valve 8 below gas-liquid separator 3, and ball valve 8 behind four-way valve 11. Set the pressure value of back pressure valve 9 to 1.5 MPa.

[0036] 3) Heat the microchannel reactor 7, and activate the insulation on the inlet and outlet pipes, as well as the gas-liquid separator 3. Turn on the peristaltic pump 2 to introduce the feed liquid from the feed liquid pretreatment system 1 and methylbutyninol into the microchannel reactor 7. This allows the feed liquid and the acetylene from the in-situ decomposition of methylbutyninol to achieve heterogeneous gas-liquid coupling within the micron-level channels of the microchannel reactor 7 module. The reaction stream is then introduced into the gas-liquid separator 3 for gas-liquid separation to obtain the reaction liquid product.

[0037] The feed rate of the raw material solution is 0.5–3 mL / min, and the feed rate of methylbutynol is 0.08–0.48 mL / min. The molar ratio of carbazole to methylbutynol is maintained at 1:1 to 1:1.05.

[0038] The reaction temperature of the microchannel reactor 7 is 180-200℃, and the insulation temperature of the pipelines and gas-liquid separator 3 in the entire reaction system is 120-150℃.

[0039] 4) The reaction process is monitored by sampling and analysis through the four-way valve 11 connected to the outlet of the microchannel reactor 7.

[0040] The reaction process is monitored by liquid phase analysis. During the monitoring process, the needle valve 10 is first opened to allow the reaction liquid to flow into the four-way valve 11. Then the needle valve 10 is closed, and the acetylene gas in the four-way valve 11 is purged with nitrogen. Then the four-way valve 11 and the ball valve 8 are opened to receive the outflowing sample.

[0041] Under single-pass reaction conditions, the molar ratio of carbazole to methylbutynol is approximately 1:1 to 1:1.05, which means that methylbutynol is in slight excess.

[0042] The single-pass reaction carbazole conversion rate is not less than 99%, and under optimal conditions, the conversion rate is higher than 99.2%, with N-vinylcarbazole selectivity greater than 99.5%.

[0043] When the carbazole content monitored by the liquid phase is less than 0.5%, the reaction is considered complete. After the reaction solution cools to 20-30°C, open the back pressure valve 9 to purge the air, use nitrogen to purge the system, and then purge the nitrogen in the air-liquid separator 3 and collect the reaction solution. If the single-pass reaction is not completed, it can be cyclical. Put the unreacted reaction solution back into the three-necked flask, repeat the above steps, and cyclical again, using liquid phase monitoring as the final control standard.

[0044] Example 1:

[0045] A method for synthesizing electronic-grade N-vinylcarbazole includes the following steps: 1) Prepare the feed solution by placing it in a three-necked flask. The feed solution consists of 25% carbazole by weight and 75% solvent, with 3% potassium ethoxide catalyst added by weight of carbazole. The solvent is dimethyl sulfoxide. Heat the three-necked flask to 150°C with a magnetic stirrer and heating mantle, and then turn on the vacuum system to remove the water from the feed solution.

[0046] 2) Set ball valve 8, needle valve 10, peristaltic pump 2, back pressure valve 9, and four-way valve 11 to the fully open position. Open the nitrogen cylinder to fill the continuous microchannel reaction system with nitrogen. Purge the system with nitrogen for 8 minutes. Then close the nitrogen cylinder. Next, close back pressure valve 9, four-way valve 11, ball valve 8 below gas-liquid separator 3, and ball valve 8 behind four-way valve 11. Set the pressure value of back pressure valve 9 to 1.5 MPa.

[0047] 3) Heat the microchannel reactor 7 to 200℃, and maintain the temperature of the inlet and outlet pipes at 150℃. Also maintain the temperature of the gas-liquid separator 3 at 150℃. Turn on the peristaltic pump 2 to introduce the feed liquid from the feed liquid pretreatment system 1 and methylbutyninol into the microchannel reactor 7. The feed rate of the feed liquid is 0.5 mL / min, and the feed rate of methylbutyninol is 0.08 mL / min. This allows the feed liquid and the acetylene from the in-situ decomposition of methylbutyninol to achieve sufficient gas-liquid heterogeneous coupling within the micron-level channels of the microchannel reactor 7 module. The reaction stream is then introduced into the gas-liquid separator 3 for gas-liquid separation to obtain the reaction liquid product.

[0048] 4) Liquid phase analysis was used to monitor the reaction process. During monitoring, needle valve 10 was first opened to allow the reaction liquid to flow into four-way valve 11. Then, needle valve 10 was closed, and acetylene gas in four-way valve 11 was purged with nitrogen. Then, four-way valve 11 and ball valve 8 were opened to receive the outflowing sample. The single-pass carbazole conversion rate was 99.4%.

[0049] Example 2:

[0050] A method for synthesizing electronic-grade N-vinylcarbazole includes the following steps: 1) Prepare the feed solution by placing it in a three-necked flask. The feed solution consists of 25% carbazole by weight and 75% solvent, with 4% potassium ethoxide catalyst added by weight of carbazole. The solvent is N-methylpyrrolidone. Heat the three-necked flask to 140°C with a magnetic stirrer and heating mantle, and then turn on the vacuum system to remove the water from the feed solution.

[0051] 2) Set ball valve 8, needle valve 10, peristaltic pump 2, back pressure valve 9, and four-way valve 11 to the fully open position. Open the nitrogen cylinder to fill the continuous microchannel reaction system with nitrogen. Purge the system with nitrogen for 10 minutes. Close the nitrogen cylinder. Then close back pressure valve 9, four-way valve 11, ball valve 8 below gas-liquid separator 3, and ball valve 8 behind four-way valve 11. Set the pressure value of back pressure valve 9 to 1.5 MPa.

[0052] 3) Heat the microchannel reactor 7 to 180℃, and maintain the temperature of the inlet and outlet pipes at 140℃. Also maintain the gas-liquid separator 3 at 140℃. Turn on the peristaltic pump 2 to introduce the feed liquid from the feed liquid pretreatment system 1 and methylbutyninol into the microchannel reactor 7. The feed rate of the feed liquid is 2 mL / min, and the feed rate of methylbutyninol is 0.32 mL / min. This allows the acetylene from the in-situ decomposition of the feed liquid and methylbutyninol to achieve sufficient gas-liquid heterogeneous coupling within the micron-level channels of the microchannel reactor 7 module. The reaction stream is then introduced into the gas-liquid separator 3 for gas-liquid separation to obtain the reaction liquid product.

[0053] 4) Liquid phase analysis was used to monitor the reaction process. During monitoring, needle valve 10 was first opened to allow the reaction liquid to flow into four-way valve 11. Then, needle valve 10 was closed, and acetylene gas in four-way valve 11 was purged with nitrogen. Then, four-way valve 11 and ball valve 8 were opened to receive the outflowing sample. The single-pass carbazole conversion rate was 99.3%.

[0054] Example 3:

[0055] A method for synthesizing electronic-grade N-vinylcarbazole includes the following steps: 1) Prepare the feed solution by placing it in a three-necked flask. The feed solution consists of 25% carbazole by weight and 75% solvent, with 5% potassium ethoxide catalyst added by weight of carbazole. The solvent is isophorone. Heat the three-necked flask to 130°C with a magnetic stirrer and heating mantle, and then turn on the vacuum system to remove the water from the feed solution.

[0056] 2) Set ball valve 8, needle valve 10, peristaltic pump 2, back pressure valve 9, and four-way valve 11 to the fully open position. Open the nitrogen cylinder to fill the continuous microchannel reaction system with nitrogen. Purge the system with nitrogen for 6 minutes. Then close the nitrogen cylinder. Next, close back pressure valve 9, four-way valve 11, ball valve 8 below gas-liquid separator 3, and ball valve 8 behind four-way valve 11. Set the pressure value of back pressure valve 9 to 1.5 MPa.

[0057] 3) Heat the microchannel reactor 7 to 190℃, and maintain the temperature of the inlet and outlet pipes at 130℃. Also maintain the gas-liquid separator 3 at 130℃. Turn on the peristaltic pump 2 to introduce the feed liquid from the feed liquid pretreatment system 1 and methylbutyninol into the microchannel reactor 7. The feed rate of the feed liquid is 3 mL / min, and the feed rate of methylbutyninol is 0.48 mL / min. This allows the feed liquid and the acetylene from the in-situ decomposition of methylbutyninol to achieve sufficient gas-liquid heterogeneous coupling within the micron-level channels of the microchannel reactor 7 module. The reaction stream is then introduced into the gas-liquid separator 3 for gas-liquid separation to obtain the reaction liquid product.

[0058] 4) Liquid phase analysis was used to monitor the reaction process. During monitoring, needle valve 10 was first opened to allow the reaction liquid to flow into four-way valve 11. Then, needle valve 10 was closed, and acetylene gas in four-way valve 11 was purged with nitrogen. Then, four-way valve 11 and ball valve 8 were opened to receive the outflowing sample. The single-pass carbazole conversion rate was 99.8%.

Claims

1. A method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor, characterized in that, Includes the following steps: 1) The raw material liquid is heated through a raw material liquid pretreatment system to keep it in a fully dissolved state at all times; 2) After purging the reaction system with nitrogen, set the reaction system pressure to 0.4–1.0 MPa; 3) The feed liquid and methylbutyninol in the feed liquid pretreatment system are introduced into the microchannel reactor, so that the acetylene from the in-situ decomposition of methylbutyninol can fully achieve gas-liquid heterogeneous coupling in the micron-level channels of the microchannel reactor module. The reaction liquid is then introduced into the gas-liquid separator for gas-liquid separation to obtain the reaction liquid product. 4) The reaction process is monitored by sampling and analysis using a four-way valve connected to the outlet of the microchannel reactor; The apparatus used in the method includes a feed liquid pretreatment system, a methylbutynol container, a nitrogen source, a microchannel reactor, and a gas-liquid separator. The feed liquid pretreatment system and the methylbutynol container are respectively connected to the inlet of the microchannel reactor via peristaltic pumps. The nitrogen source is also connected to the inlet of the microchannel reactor, and the outlet of the microchannel reactor is connected to the gas-liquid separator.

2. The method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor according to claim 1, characterized in that, It also includes a four-way valve, which is also connected to the outlet of the microchannel reactor.

3. The method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor according to claim 2, characterized in that, The four-way valve is equipped with a needle valve at the inlet where it connects to the microchannel reactor, a nitrogen source at the other inlet of the four-way valve, and a ball valve at one outlet of the four-way valve.

4. The method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor according to claim 1, characterized in that, The gas-liquid separator is equipped with a ball valve at its inlet and a back pressure valve at its outlet.

5. The method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor according to claim 1, characterized in that, The feed solution consists of 25%–30% carbazole and 70%–75% solvent by weight, with 3%–5% potassium ethoxide catalyst added by weight of carbazole.

6. The method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor according to claim 5, characterized in that, The solvent is one of dimethyl sulfoxide, N-methylpyrrolidone, and isophorone.

7. The method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor according to claim 1, characterized in that, In step 1) above, the heating temperature of the raw material liquid is 120-150℃.

8. The method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor according to claim 1, characterized in that, In step 3) above, the feed rate of the raw material liquid is 0.5 to 3 mL / min, the feed rate of methylbutynol is 0.08 to 0.48 mL / min, and the molar ratio of carbazole to methylbutynol is maintained at 1:1 to 1:1.

05.

9. The method for synthesizing electronic-grade N-vinylcarbazole using a microchannel reactor according to claim 1, characterized in that, The reaction temperature of the microchannel reactor is 180–200°C, and the insulation temperature of the pipelines and gas-liquid separator in the entire reaction system is 120–150°C.

Images