A process and apparatus for the continuous preparation of chloroethylene carbonate

Abstract

This invention discloses a process and apparatus for the continuous preparation of chloroethylene carbonate, belonging to the field of chloroethylene carbonate production technology. The apparatus comprises a tubular reactor, a gas-liquid separator, an intermediate storage tank, a centrifugal pump, and a refining vessel. The apparatus can consist of multiple tubular reactors, gas-liquid separators, intermediate storage tanks, and centrifugal pumps connected by pipelines, ultimately connected to the refining vessel. An ultraviolet lamp is installed inside the tubular reactor. This invention uses ethylene carbonate and chlorine as raw materials, employing a multi-stage tubular reactor to increase the contact area between ethylene carbonate and chlorine. This apparatus achieves the goal of continuous production of chloroethylene carbonate without an initiator, with a short reaction time, low product impurities, and improved reaction yield.

Description

Technical Field

[0001] This invention belongs to the field of vinyl chloride carbonate technology, and relates to the preparation of vinyl chloride carbonate, particularly a process and apparatus for the continuous preparation of vinyl chloride carbonate. Background Technology

[0002] Benefiting from the global trend of energy conservation and emission reduction and the EU's carbon emission agreement, the global lithium battery market demand has entered a period of rapid development. Looking at the operation of the lithium-ion battery industry, my country's lithium-ion battery industry is currently accelerating the modernization of its industrial chain and supply chain, achieving sustained and rapid growth across the industry, and continuously improving its supply capacity of advanced products.

[0003] The use of electrolyte additives fluoroethylene carbonate (FEC) and vinylene carbonate (VC) has increased rapidly. However, the production capacity of chloroethylene carbonate (CEC), an important raw material for the synthesis of FEC and VC, is limited by the process and its growth is slow.

[0004] Ethylene chloride carbonate, as a key intermediate in the production of lithium battery electrolyte products, has enormous growth potential.

[0005] However, most commercially available chloroethylene carbonate preparation processes utilize intermittent reactions with initiators, resulting in long reaction times, numerous impurities such as dichloroethylene carbonate byproducts, and low yields of the obtained chloroethylene carbonate product. Summary of the Invention

[0006] To address the aforementioned problems, the first aspect of this invention provides an apparatus for the continuous preparation of chloroethylene carbonate, using a multi-stage tubular reactor to increase the contact area between ethylene carbonate and chlorine gas.

[0007] The second aspect of this invention provides a process for the continuous preparation of chloroethylene carbonate, using ethylene carbonate and chlorine as raw materials and employing a multi-stage tubular reactor. This process achieves the goal of continuous production of chloroethylene carbonate without the need for an initiator, increases the contact area between the raw material ethylene carbonate and chlorine, shortens the reaction time, reduces product impurities, and improves the reaction yield.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] An apparatus for the continuous preparation of chloroethylene carbonate, the apparatus comprising at least one tubular reactor, at least one gas-liquid separator, at least one intermediate storage tank, multiple centrifugal pumps, and a refining vessel, wherein the tubular reactor, the gas-liquid separator, the intermediate storage tank, and the centrifugal pumps are connected by pipelines and finally connected to the refining vessel; the tubular reactor includes multiple transverse reaction pipes, each transverse reaction pipe having an external jacket and an internal ultraviolet lamp, and the transverse reaction pipes having an ethylene carbonate inlet, multiple chlorine inlets, and a discharge port.

[0010] As a preferred embodiment of the present invention, the transverse reaction pipe has a diameter of 1 to 3 inches and a length of 3 to 5 meters.

[0011] As a preferred embodiment of the present invention, the plurality of chlorine inlets are at a 45° angle to the transverse reaction pipe.

[0012] The presence of multiple chlorine inlets may increase the contact area between the raw material ethylene carbonate and chlorine.

[0013] As a preferred embodiment of the present invention, the device consists of 2 to 4 tubular reactors, 2 to 4 gas-liquid separators, 2 to 4 intermediate storage tanks, and 2 to 4 centrifugal pumps connected by pipelines, and finally connected to a refining kettle.

[0014] More preferably, the device consists of 3 to 4 tubular reactors, 3 to 4 gas-liquid separators, 3 to 4 intermediate storage tanks, and 3 to 4 centrifugal pumps connected by pipelines, and finally connected to a refining kettle.

[0015] As a preferred embodiment of the present invention, the transverse reaction pipe is made of stainless steel lined with PTFE, enamel, glass or ceramic, which can resist chlorine corrosion.

[0016] The number of transverse reaction pipes can be adjusted according to the required production volume.

[0017] The present invention also provides a process for the continuous preparation of chloroethylene carbonate, using the above-mentioned apparatus, comprising the following steps:

[0018] 1) The raw materials ethylene carbonate and chlorine are thoroughly mixed in a tubular reactor and then subjected to a chlorination reaction initiated by ultraviolet light;

[0019] 2) The crude liquid obtained in the tubular reactor is separated by a gas-liquid separator, and the liquid enters the intermediate storage tank;

[0020] 3) The liquid in the intermediate storage tank is pumped to the refining kettle for refining by centrifugal pump. All the tail gas enters the external tail gas absorption system. The reaction time is 6 to 12 hours to obtain the product chloroethylene carbonate.

[0021] As a preferred embodiment of the present invention, in step 1), the reaction temperature of ethylene carbonate and chlorine is 50-95°C; the flow rate of chlorine in the transverse reaction pipe is 120-140 L / min, and the mass ratio of chlorine to ethylene carbonate is 1:0.7-0.9.

[0022] More preferably, the flow rate of chlorine is 130 L / min; the mass ratio of ethylene carbonate is 1:0.8; and the reaction temperature of ethylene carbonate and chlorine is 60–80 °C.

[0023] As a preferred embodiment of the present invention, in step 1), the ultraviolet lamp is a low-heat cold light source ultraviolet lamp with a light source wavelength of 300-400nm and an ultraviolet lamp power of 10-20W.

[0024] More preferably, the ultraviolet lamp is a low-heat cold light source ultraviolet lamp with a light source wavelength of 365nm and an ultraviolet lamp power of 15W.

[0025] As a preferred embodiment of the present invention, in step 2), the exhaust gas outlet at the top of the gas-liquid separator is connected to an external exhaust gas absorption system.

[0026] As a preferred embodiment of the present invention, in step 3), the tail gas outlet at the top of the refining vessel is connected to an external tail gas absorption system, and the top of the refining vessel is also provided with a nitrogen inlet.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] This invention uses ethylene carbonate and chlorine as raw materials and employs a multi-stage tubular reactor preparation device to increase the contact area between ethylene carbonate and chlorine. This allows for the continuous production of chloroethylene carbonate without the need for an initiator, and also results in a short reaction time, low product impurities, and improved reaction yield. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the present invention.

[0030] Figure 2 This is an enlarged view of the tubular reactor of the present invention.

[0031] In the diagram, 1 is a tubular reactor; 2 is a gas-liquid separator; 3 is an intermediate storage tank; 4 is a centrifugal pump; 5 is a refining kettle; 6 is a horizontal reaction pipe; 7 is a jacket; 8 is an ethylene carbonate inlet; 9 is a chlorine inlet; 10 is a discharge port; 11 is an ultraviolet lamp; and 12 is a nitrogen inlet. Detailed Implementation

[0032] To facilitate understanding of the technical means, creative features, objectives, and effects of this invention, the invention is further described below with reference to specific embodiments and accompanying drawings. However, the following embodiments are merely preferred embodiments of this invention and not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments described herein without creative effort are all within the scope of protection of this invention. Unless otherwise specified, the experimental methods in the following embodiments are conventional methods, and the materials and reagents used in the following embodiments are commercially available unless otherwise specified.

[0033] See Figure 1 The present invention first provides an apparatus for the continuous preparation of chloroethylene carbonate, the apparatus consisting of 2 to 4 tubular reactors 1, 2 to 4 gas-liquid separators 2, 2 to 4 intermediate storage tanks 3, and 2 to 4 centrifugal pumps 4 connected by pipelines, and finally connected to a refining kettle 5.

[0034] See Figure 2 The tubular reactor 1 includes multiple transverse reaction pipes 6, with a jacket 7 on the outside of the transverse reaction pipes 6 and an ultraviolet lamp 11 inside the transverse reaction pipes 6. The transverse reaction pipes 6 are equipped with an ethylene carbonate inlet 8, multiple chlorine inlets 9 and a discharge port 10.

[0035] The jacket 7 can control the temperature. The medium inside the jacket 7 is circulating water, and the temperature is controlled at 50-70℃.

[0036] The transverse reaction pipe 6 has a diameter of 1 to 3 inches and a length of 3 to 5 meters. Multiple chlorine gas inlets 9 are at a 45° angle to the transverse reaction pipe 6.

[0037] The transverse reaction pipe 6 is made of stainless steel lined with PTFE, enamel, glass or ceramic, and is resistant to chlorine corrosion.

[0038] The exhaust gas outlet at the top of the gas-liquid separator 2 is connected to an external exhaust gas absorption system.

[0039] The tail gas outlet at the top of the refining vessel 5 is connected to an external tail gas absorption system, and the top of the refining vessel 5 is also equipped with a nitrogen inlet 12. Example 1

[0040] This embodiment provides a process for the continuous preparation of chloroethylene carbonate using an apparatus, wherein, see [link to relevant documentation]. Figure 1 and Figure 2 The preparation apparatus consists of three tubular reactors, three gas-liquid separators, three intermediate storage tanks, and three centrifugal pumps connected by pipelines, and finally connected to a refining kettle. In this process, the chlorine flow rate is 130 L / min, the mass ratio of chlorine to ethylene carbonate is 1:0.8, and the ultraviolet lamps in the tubular reactors are low-heat ultraviolet cold light sources with a wavelength of 365 nm and a power of 15 W.

[0041] The process includes:

[0042] Step 1) The raw material ethylene carbonate and chlorine are thoroughly mixed in a tubular reactor at a reaction temperature of 70°C. The chlorination reaction is carried out under ultraviolet light. The entire process takes 8 hours to obtain the product.

[0043] Step 2) The crude liquid obtained in the tubular reactor is separated by a gas-liquid separator, and the liquid enters the intermediate storage tank.

[0044] Step 3) The liquid in the intermediate storage tank is pumped to the refining kettle for refining via a centrifugal pump. All exhaust gas enters the exhaust gas absorption system to obtain the product. Testing revealed that the product contained 83.2% chloroethylene carbonate, 8.4% ethylene carbonate, 7% dichloroethylene carbonate, and 1.4% other impurities. Example 2

[0045] This embodiment provides a process for the continuous preparation of chloroethylene carbonate. The preparation apparatus consists of four tubular reactors, four gas-liquid separators, four intermediate storage tanks, and four centrifugal pumps connected by pipelines, finally connected to a refining vessel. In this process, the chlorine flow rate is 130 L / min, the mass ratio of chlorine to ethylene carbonate is 1:0.8, and the ultraviolet lamps in the tubular reactors are low-heat ultraviolet cold light sources with a wavelength of 365 nm and a power of 15 W.

[0046] Step 1) The raw material ethylene carbonate and chlorine gas are thoroughly mixed in a tubular reactor at a reaction temperature of 70 °C. The chlorination reaction is carried out under ultraviolet light. The entire process takes 10 hours to obtain the product.

[0047] Step 2) The crude liquid obtained in the tubular reactor is separated by a gas-liquid separator, and the liquid enters the intermediate storage tank.

[0048] Step 3) The liquid in the intermediate storage tank is pumped to the refining kettle for refining via a centrifugal pump. All exhaust gas enters the exhaust gas absorption system to obtain the product. Testing revealed that the product contained 84.1% chloroethylene carbonate, 7.5% ethylene carbonate, 7.3% dichloroethylene carbonate, and 1.1% other impurities. Example 3

[0049] This embodiment provides a process for the continuous preparation of chloroethylene carbonate. The preparation apparatus consists of four tubular reactors, four gas-liquid separators, four intermediate storage tanks, and four centrifugal pumps connected by pipelines, finally connected to a refining vessel. In this process, the chlorine flow rate is 120 L / min, the mass ratio of chlorine to ethylene carbonate is 1:0.8, and the ultraviolet lamps in the tubular reactors are low-heat ultraviolet cold light sources with a wavelength of 365 nm and a power of 15 W.

[0050] Step 1) The raw material ethylene carbonate and chlorine gas are thoroughly mixed in a tubular reactor at a reaction temperature of 70 °C. The chlorination reaction is carried out under ultraviolet light. The entire process takes 12 hours to obtain the product.

[0051] Step 2) The crude liquid obtained in the tubular reactor is separated by a gas-liquid separator, and the liquid enters the intermediate storage tank.

[0052] Step 3) The liquid in the intermediate storage tank is pumped to the refining kettle for refining via a centrifugal pump. All exhaust gas enters the exhaust gas absorption system to obtain the product. The product was tested and found to contain 85.5% chloroethylene carbonate, 8.1% ethylene carbonate, 5.5% dichloroethylene carbonate, and 0.9% other impurities.

[0053] Comparative Example 1

[0054] Comparative Example 1 uses the same preparation apparatus as Example 1, except that in step 1), the raw material ethylene carbonate and chlorine are thoroughly mixed in a tubular reactor at a reaction temperature of 50 °C and chlorination is carried out under ultraviolet light. The entire process takes 8 hours to obtain the product.

[0055] Step 2) The crude liquid obtained in the tubular reactor is separated by a gas-liquid separator, and the liquid enters the intermediate storage tank.

[0056] Step 3) The liquid in the intermediate storage tank is pumped to the refining kettle for refining via a centrifugal pump. All exhaust gas enters the exhaust gas absorption system to obtain the product. The product was tested and found to contain 42.9% chloroethylene carbonate, 52.3% ethylene carbonate, 1.6% dichloroethylene carbonate, and 3.2% other components.

[0057] Comparative Example 2

[0058] Comparative Example 2 uses the same preparation apparatus as Example 1, except that in step 1), the raw material ethylene carbonate and chlorine are thoroughly mixed in a tubular reactor at a reaction temperature of 90 °C and chlorination is carried out under ultraviolet light. The entire process takes 7 hours to obtain the product.

[0059] Step 2) The crude liquid obtained in the tubular reactor is separated by a gas-liquid separator, and the liquid enters the intermediate storage tank.

[0060] Step 3) The liquid in the intermediate storage tank is pumped to the refining kettle for refining via a centrifugal pump. All exhaust gas enters the exhaust gas absorption system to obtain the product. The product was tested and found to contain 22.3% chloroethylene carbonate, 56.8% ethylene carbonate, 5.4% dichloroethylene carbonate, and 15.5% other components.

[0061] Comparative Example 3

[0062] Comparative Example 3 uses the same preparation apparatus as Example 1, except that the flow rate of chlorine gas in the process is 140 L / min.

[0063] Step 1) The raw material ethylene carbonate and chlorine are thoroughly mixed in a tubular reactor at a reaction temperature of 70°C. The chlorination reaction is carried out under ultraviolet light. The entire process takes 7 hours to obtain the product.

[0064] Step 2) The crude liquid obtained in the tubular reactor is separated by a gas-liquid separator, and the liquid enters the intermediate storage tank.

[0065] Step 3) The liquid in the intermediate storage tank is pumped to the refining kettle for refining via a centrifugal pump. All exhaust gas enters the exhaust gas absorption system to obtain the product. Testing revealed that the product contains 81.8% chloroethylene carbonate, 7.9% ethylene carbonate, 8.5% dichloroethylene carbonate, and 1.8% other components.

[0066] Based on the product concentrations of the various embodiments and comparative examples, the experimental data are shown in Table 1.

[0067]

[0068] As shown in Table 1, the present invention uses ethylene carbonate and chlorine as raw materials and employs a multi-stage tubular reactor preparation device to increase the contact area between ethylene carbonate and chlorine, thereby enabling continuous production of chloroethylene carbonate without the need for an initiator. Furthermore, the reaction time is short, the product has low impurities, and the reaction yield is improved.

[0069] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the method of the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A process for the continuous preparation of chloroethylene carbonate, characterized in that, An apparatus for the continuous preparation of chloroethylene carbonate is used, the process comprising the following steps: 1) The raw materials ethylene carbonate and chlorine are thoroughly mixed in a tubular reactor and then subjected to a chlorination reaction initiated by ultraviolet light; 2) The crude liquid obtained in the tubular reactor is separated by a gas-liquid separator, and the liquid enters the intermediate storage tank; 3) The liquid in the intermediate storage tank is pumped to the refining kettle for refining by centrifugal pump. All the tail gas enters the external tail gas absorption system. The reaction time is 6 to 12 hours to obtain the product chloroethylene carbonate. In step 1), the reaction temperature of ethylene carbonate and chlorine is 50–95°C; the flow rate of chlorine in the transverse reaction pipe is 120–140 L / min, and the mass ratio of chlorine to ethylene carbonate is 1:0.7–0.

9. An apparatus for the continuous production of chloroethylene carbonate includes at least one tubular reactor, at least one gas-liquid separator, at least one intermediate storage tank, multiple centrifugal pumps, and a refining vessel. The tubular reactor, the gas-liquid separator, the intermediate storage tank, and the centrifugal pumps are connected by pipelines and finally connected to the refining vessel. The tubular reactor includes multiple transverse reaction pipes, each with an external jacket and an internal ultraviolet lamp. The transverse reaction pipes are equipped with an ethylene carbonate inlet, multiple chlorine inlets, and a discharge port. The ultraviolet lamp is a low-heat, cold-light source ultraviolet lamp with a wavelength of 300–400 nm and a power of 10–20 W. The multiple chlorine gas inlets are at a 45° angle to the transverse reaction pipe; The device consists of 2 to 4 tubular reactors, 2 to 4 gas-liquid separators, 2 to 4 intermediate storage tanks, and 2 to 4 centrifugal pumps connected by pipelines, and finally connected to a refining kettle.

2. The process for continuous preparation of chloroethylene carbonate according to claim 1, characterized in that, In step 2), the exhaust gas outlet at the top of the gas-liquid separator is connected to an external exhaust gas absorption system.

3. The process for continuous preparation of chloroethylene carbonate according to claim 1, characterized in that, In step 3), the tail gas outlet at the top of the refining vessel is connected to an external tail gas absorption system, and the top of the refining vessel is also equipped with a nitrogen inlet.

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