Ethylene carbonate and polyurethane chain extender joint production device and process

Abstract

The invention discloses an ethylene carbonate and polyurethane chain extender joint production device and process, the joint production device comprises a device main body, the device main body comprises a first raw material transportation unit, an ethylene carbonate reactor, a film evaporator, a second raw material transportation unit, a polyurethane chain extender reactor and a crystallization kettle. According to the design of the joint production device, recycling of materials is fully considered, and the product structure can be flexibly adjusted when market conditions change by adjusting the production proportion of ethylene carbonate and the polyurethane chain extender, so that competitiveness is kept, and high economic benefits are achieved. In addition, due to the closed-loop characteristic of the joint production device, the influence on the environment is reduced, the utilization rate of raw materials is increased, and the double advantages of economy, high efficiency and environment friendliness are reflected.

Description

Technical Field

[0001] The invention relates to the technical field of chemical production equipment, and in particular to an ethylene carbonate and polyurethane chain extender combined production equipment and process. Background Art

[0002] Ethylene carbonate (EC) has a melting point of 35°C~38°C and is solid at room temperature. It is an important organic solvent and chemical intermediate. It is mainly used as a solvent or synthetic VC and FEC additive in the lithium-ion battery electrolyte industry. It can also be used as a synthetic DMC in the polycarbonate industry.

[0003] Existing invention patents CN106478583A, CN106478586A, etc. on the synthesis of ethylene carbonate all propose solutions to technical problems such as untimely removal of reaction heat, low conversion rate of epoxy compounds, and product purity that cannot meet the requirements of electronic-grade products; invention patents CN107915708A, CN107915710A, etc. solve the problem of low activity and easy deactivation of alkaline catalysts in the production of ethylene carbonate from the perspective of alkaline catalyst preparation; the technical solution proposed by invention patent CN110437201A mainly solves the problem of absorbing ethylene oxide that does not participate in the reaction process and converting it into coupled production of ethylene carbonate; the above technical solutions have accelerated the technical upgrade process of equipment, processes, and alkaline catalysts in the reaction process, but have not made more optimizations for the recovery of alkaline catalysts. At the same time, the technical upgrade has increased the investment in single ethylene carbonate products. Combined with the multiple influences of the macro-economy, industry competition pattern, market supply and demand, and raw material costs, the price of ethylene carbonate is lower than the production cost for a certain period of time, causing enterprises to reduce production, thereby affecting the operating rate. Therefore, it is urgent to develop new technologies. At the same time, the research and development of cyclic carbonate as a raw material for the synthesis of polymer materials has also attracted the attention of technicians due to the influence of the price of ethylene carbonate. For example, in terms of polyurethane chain extender materials, cyclic carbonate can provide a cheap and effective raw material for the synthesis of chain extenders, which can be used to replace ethylene oxide with high safety risks and high cost and environmental protection disposal. For example, the invention patent CN113501933 A proposed to mix ethylene carbonate and hexamethylenediamine and vacuumize until no bubbles are generated to prepare the polyurethane chain extender 1,6-bis (2-hydroxy-ethoxycarbonylamine) hexane (DHDU); the invention patents CN115850032A and CN101244989A proposed to use ethylene oxide, hydroquinone, water, alkaline catalysts and other reactions to prepare the polyurethane chain extender hydroquinone dihydroxyethyl ether (HQEE). The above products can be used as crosslinkers for mixing, casting and thermoplastic polyurethane elastomers, which can improve the stability of the products and improve various physical properties such as tear strength, heat resistance, hardness, elasticity, compression deformation, etc. However, the gas CO generated in the above preparation process 2Ethylene oxide was not used effectively or was used at high risk, and alkaline catalysts were not recycled.

[0004] Therefore, it is urgent to develop a combined production device and process for ethylene carbonate and polyurethane chain extender to solve the shortcomings of the existing technology. Summary of the invention

[0005] In view of the above problems, the present invention discloses a combined production device and process of ethylene carbonate and polyurethane chain extender. The design of the combined production device fully considers the recycling of materials. By adjusting the production ratio of ethylene carbonate and polyurethane chain extender, the product structure can be flexibly adjusted when market conditions change to maintain competitiveness and achieve high economic benefits. In addition, the closed-loop characteristics of the combined production device reduce the impact on the environment and improve the utilization rate of raw materials, reflecting the dual advantages of economic efficiency and environmental friendliness.

[0006] To achieve the above-mentioned purpose, the first aspect of the present invention provides a device for the combined production of ethylene carbonate and polyurethane chain extender, comprising a device body, the device body comprising a first raw material transport unit, an ethylene carbonate reactor, a thin film evaporator, a second raw material transport unit, a polyurethane chain extender reactor and a crystallization kettle, the outlet end of the first raw material transport unit is connected to the inlet end of the ethylene carbonate reactor, the outlet end of the ethylene carbonate reactor is connected to the inlet end of the thin film evaporator, the thin film evaporator comprises a first liquid phase outlet end and a first gas phase outlet end, the first liquid phase outlet end is connected to the first inlet end of the polyurethane chain extender reactor, and the first gas phase outlet end is used to produce ethylene carbonate; the outlet end of the second raw material transport unit is connected to the second inlet end of the polyurethane chain extender reactor, the polyurethane chain extender reactor comprises a second liquid phase outlet end and a second gas phase outlet end, the crystallization kettle comprises a third liquid phase outlet end and a fourth liquid phase outlet end, the second liquid phase outlet end is connected to the inlet end of the crystallization kettle, the second gas phase outlet end and the third liquid phase outlet end are both connected to the inlet end of the ethylene carbonate reactor, and the fourth liquid phase outlet end is used to produce the polyurethane chain extender.

[0007] Compared with the prior art, the production device of the present invention can realize the joint production of ethylene carbonate and polyurethane chain extender in the same production device. The thin film evaporator of the present invention is provided with a first liquid phase outlet and a first gas phase outlet. The first gas phase outlet can extract part of ethylene carbonate to realize the production of ethylene carbonate products. The first liquid phase outlet is connected to the first inlet of the polyurethane chain extender, so that the alkaline catalyst and the unextracted ethylene carbonate can enter the polyurethane chain extender reactor as production raw materials. The above arrangement enables the adjustment of the production ratio of ethylene carbonate and polyurethane chain extender by adjusting the extraction amount of ethylene carbonate, and thus the product structure can be flexibly adjusted when market conditions change to maintain competitiveness and achieve high economic benefits. At the same time, the second gas phase outlet in the polyurethane chain extender reactor and the third liquid phase outlet in the crystallization kettle are both connected to the inlet of the ethylene carbonate reactor. Such an arrangement can realize the recycling of carbon dioxide, alkaline catalyst and unreacted ethylene carbonate. In summary, the setting of the combined production device of the present invention fully considers the recycling and use of materials, and has a closed-loop characteristic, which reduces the impact on the environment and improves the utilization rate of raw materials, reflecting the dual advantages of economic efficiency and environmental friendliness.

[0008] As a preferred technical solution, the first raw material transportation unit of the present invention includes an ethylene oxide delivery pipe, a carbon dioxide delivery pipe and an alkaline catalyst delivery pipe, and the ethylene oxide delivery pipe, the carbon dioxide delivery pipe and the alkaline catalyst delivery pipe are respectively connected to the inlet end of the ethylene carbonate reactor through pipelines.

[0009] As a preferred technical solution, the second raw material transport unit of the present invention includes a functional monomer transport pipe, which is connected to the second inlet end of the polyurethane chain extender reactor.

[0010] As a preferred technical solution, a compression device is further provided between the second gas phase outlet and the inlet of the ethylene carbonate reactor of the present invention to pressurize and liquefy the carbon dioxide for recycling.

[0011] The second aspect of the present invention provides a process for the combined production of ethylene carbonate and polyurethane chain extender, using the aforementioned combined production device for ethylene carbonate and polyurethane chain extender, comprising the steps of: (1) Ethylene oxide, carbon dioxide and alkaline catalyst are introduced into the ethylene carbonate reactor in a certain proportion for reaction, and the finished mixture is introduced into the thin film evaporator for treatment to extract part of the ethylene carbonate; (2) The remaining ethylene carbonate, alkaline catalyst, and functional monomer raw materials enter the polyurethane chain extender reactor for reaction, and the generated carbon dioxide enters the ethylene carbonate reactor for recycling. The polyurethane chain extender, alkaline catalyst, and unreacted ethylene carbonate enter the crystallization kettle, and are first cooled to allow the polyurethane chain extender to crystallize. The alkaline catalyst and ethylene carbonate enter the ethylene carbonate reactor for recycling, and then are heated to extract the polyurethane chain extender.

[0012] As a preferred technical solution, in step (1), the reaction temperature is 100°C to 200°C, and the reaction pressure is 4MPa to 10MPa.

[0013] As a preferred technical solution, in step (1), the processing temperature of the thin film evaporator is 100°C~200°C, and the processing pressure is 1kPa~10kPa.

[0014] As a preferred technical solution, in step (2), the reaction temperature is 100°C to 200°C, and the reaction pressure is 100 kPa to 101.325 kPa.

[0015] As a preferred technical solution, in step (2), the temperature of the cooling treatment is 40°C~95°C.

[0016] As a preferred technical solution, in step (2), the temperature of the heating treatment is 98°C~110°C.

[0017] As a preferred technical solution, the alkaline catalyst is selected from tetrabutylammonium bromide or ionic liquid. As a preferred technical solution, the functional monomer raw material is selected from hydroquinone or hexamethylenediamine.

[0018] As a preferred technical solution, the amount of carbon dioxide recovered accounts for 0% to 5% of the sum of the feed amounts of ethylene oxide, carbon dioxide and alkaline catalyst.

[0019] As a preferred technical solution, the amount of alkaline catalyst recovered accounts for 0% to 5% of the sum of the feed amounts of ethylene oxide, carbon dioxide and alkaline catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the combined production device of ethylene carbonate and polyurethane chain extender of the present invention.

[0021] Explanation of component symbols: 100-device body, 10-first raw material transport unit, 11-ethylene oxide transport pipe, 12 carbon dioxide transport pipe, 13-alkaline catalyst transport pipe, 20-ethylene carbonate reactor, 30-thin film evaporator, 31-first liquid phase outlet, 32-first gas phase outlet, 40-second raw material transport unit, 41-functional monomer transport pipe, 50-polyurethane chain extender reactor, 51-second liquid phase outlet, 52-second gas phase outlet, 60-crystallization kettle, 61-third liquid phase outlet, 62-fourth liquid phase outlet, 70-compression device. DETAILED DESCRIPTION

[0022] The present invention first discloses a device for producing ethylene carbonate and polyurethane chain extender. Figure 1 As shown, the device includes a device body 100 , which includes a first raw material transport unit 10 , an ethylene carbonate reactor 20 , a thin film evaporator 30 , a second raw material transport unit 40 , a polyurethane chain extender reactor 50 and a crystallization kettle 60 .

[0023] Among them, the function of the first raw material transportation unit 10 is to transport the reaction raw materials to the ethylene carbonate reactor. The outlet end (not shown in the figure) of the first raw material transportation unit 10 is connected to the inlet end (not shown in the figure) of the ethylene carbonate reactor 20. In the present invention, the first raw material transportation unit 10 includes an ethylene oxide delivery pipe 11, a carbon dioxide delivery pipe 12 and an alkaline catalyst delivery pipe 13, and the ethylene oxide delivery pipe 11, the carbon dioxide delivery pipe 12 and the alkaline catalyst delivery pipe 13 are respectively connected to the inlet end of the ethylene carbonate reactor 20 through pipelines. In some embodiments, the output ends of the ethylene oxide delivery pipe 11, the carbon dioxide delivery pipe 12 and the alkaline catalyst delivery pipe 13 are respectively connected to the inlet end pipeline of the ethylene carbonate reactor 20 by welding.

[0024] The ethylene carbonate reactor 20 is a place where ethylene oxide, carbon dioxide and an alkaline catalyst react to synthesize ethylene carbonate. The ethylene carbonate reactor 20 can be specifically a high-pressure reactor. The outlet end (not shown in the figure) of the ethylene carbonate reactor 20 is connected to the inlet end (not shown in the figure) of the thin film evaporator 30 to transport the finished product mixture to the thin film evaporator 30 for treatment. In some embodiments, the outlet end of the ethylene carbonate reactor 20 is connected to the inlet end of the thin film evaporator 30 by a pipeline. In some embodiments, the inlet end of the ethylene carbonate reactor 20 is arranged on the bottom side of the ethylene carbonate reactor 20, and the outlet end of the ethylene carbonate reactor 20 is arranged on the top side of the ethylene carbonate reactor 20. Such an arrangement can increase the contact time of ethylene oxide, carbon dioxide and the alkaline catalyst in the reaction system so that the reaction is more fully carried out, which can effectively improve the conversion rate of the product, and is more conducive to the output of the finished product mixture, which can effectively improve the production efficiency.

[0025] The thin film evaporator 30 is used to evaporate the finished product mixture output from the ethylene carbonate reactor 20 to extract part of the finished ethylene carbonate, and transport the catalyst and the remaining part of the ethylene carbonate as reaction raw materials to the polyurethane chain extender reactor to participate in the reaction. The thin film evaporator 30 includes a first liquid phase outlet 31 and a first gas phase outlet 32. The first liquid phase outlet 31 is connected to the first inlet (not shown in the figure) of the polyurethane chain extender reactor 50. The first gas phase outlet 32 ​​is used to extract ethylene carbonate. The extracted ethylene carbonate can enter the distillation device (not shown in the figure) for refining to obtain electronic grade ethylene carbonate or industrial grade ethylene carbonate. In some embodiments, the first liquid phase outlet 31 is connected to the first inlet of the polyurethane chain extender reactor 50 through a pipeline. In some embodiments, the inlet of the thin film evaporator 30 is arranged at the top of the thin film evaporator, the first gas phase outlet 32 ​​is arranged on one side of the top of the thin film evaporator 30, and the first liquid phase outlet 31 is arranged at the bottom of the thin film evaporator 30.

[0026] The second raw material transport unit 40 is used to transport the functional monomer raw material to the polyurethane chain extender reactor. The outlet end (not shown in the figure) of the second raw material transport unit 40 is connected to the second inlet end (not shown in the figure) of the polyurethane chain extender reactor 50. In the present invention, the second raw material transport unit 40 includes a functional monomer transport pipe 41, which is connected to the second inlet end of the polyurethane chain extender reactor 50. In some embodiments, the functional monomer transport pipe 41 is welded to the second inlet end of the polyurethane chain extender reactor 50.

[0027] The polyurethane chain extender reactor 50 is a place where functional monomer raw materials, alkaline catalysts and ethylene carbonate react to synthesize polyurethane chain extenders. The alkaline catalyst and ethylene carbonate are output from the first liquid phase outlet 31 of the thin film evaporator 30 and enter the polyurethane chain extender reactor 50 through the first inlet of the polyurethane chain extender reactor 50. The functional monomer raw materials are output through the functional monomer delivery pipe 41 and enter the polyurethane chain extender reactor 50 through the second inlet of the polyurethane chain extender reactor 50. After entering the polyurethane chain extender reactor 50, the above raw materials react to generate carbon dioxide and polyurethane chain extender. The polyurethane chain extender reactor 50 includes a second liquid phase outlet 51 and a second gas phase outlet 52. The second gas phase outlet 52 is connected to the inlet of the ethylene carbonate reactor 20 to transport the carbon dioxide to the ethylene carbonate reactor 20 for recycling. A compression device 70 is also provided between the second gas phase outlet 52 and the inlet of the ethylene carbonate reactor 20 to pressurize and liquefy the carbon dioxide before transporting it to the inlet of the ethylene carbonate reactor for recycling. In the present invention, the compression device can be a carbon dioxide compressor. The second liquid phase outlet 51 of the present invention is connected to the inlet of the crystallization kettle 60 (not shown in the figure) to transport the finished polyurethane chain extender, the alkaline catalyst and the unreacted ethylene carbonate to the crystallization kettle 60 for treatment. In some embodiments, the first inlet and the second inlet of the polyurethane chain extender reactor 50 are arranged at the top of the polyurethane chain extender reactor 50, the second gas phase outlet 52 is arranged at the top of the polyurethane chain extender reactor 50, and the second liquid phase outlet 51 is arranged at the bottom of the polyurethane chain extender reactor 50. In some embodiments, the second gas phase outlet 52 is connected to the inlet of the ethylene carbonate reactor 20 through a pipeline, and the second liquid phase outlet 51 is connected to the inlet of the crystallization kettle 60 through a pipeline.

[0028] The crystallization kettle 60 is used to separate the finished polyurethane chain extender, the alkaline catalyst and the unreacted ethylene carbonate input from the polyurethane chain extender reactor. The crystallization kettle 60 includes a third liquid phase outlet 61 and a fourth liquid phase outlet 62, and the third liquid phase outlet 61 is connected to the inlet of the ethylene carbonate reactor 20 to transport the alkaline catalyst and ethylene carbonate to the ethylene carbonate reactor 20 for recycling. The fourth liquid phase outlet 62 is used to extract the polyurethane chain extender, and the extracted polyurethane chain extender can be further refined to obtain a polyurethane chain extender product with higher purity. In some embodiments, the inlet of the crystallization kettle 60 is arranged at the top of the crystallization kettle 60, and the third liquid phase outlet 61 and the fourth liquid phase outlet 62 are arranged at the bottom of the crystallization kettle. In some embodiments, the third liquid phase outlet 61 is connected to the inlet of the ethylene carbonate reactor 20 by a pipeline.

[0029] The present invention also provides a process for the combined production of ethylene carbonate and polyurethane chain extender, which uses the aforementioned combined production device for ethylene carbonate and polyurethane chain extender, and comprises the following steps: (1) Ethylene oxide, carbon dioxide and alkaline catalyst are introduced into the ethylene carbonate reactor in a certain proportion for reaction, and the finished mixture is introduced into the thin film evaporator for treatment to extract part of the ethylene carbonate; (2) The remaining ethylene carbonate, alkaline catalyst, and functional monomer raw materials enter the polyurethane chain extender reactor for reaction, and the generated carbon dioxide enters the ethylene carbonate reactor for recycling. The polyurethane chain extender, alkaline catalyst, and unreacted ethylene carbonate enter the crystallization kettle, and are first cooled to allow the polyurethane chain extender to crystallize. The alkaline catalyst and ethylene carbonate enter the ethylene carbonate reactor for recycling, and then are heated to extract the polyurethane chain extender.

[0030] In step (1), the alkaline catalyst is selected from ionic liquids, and the ionic liquids may be imidazole ionic liquids, pyridine ionic liquids, quaternary ammonium ionic liquids and quaternary phosphine ionic liquids. Preferably, the alkaline catalyst is selected from quaternary ammonium ionic liquids, and more preferably, the alkaline catalyst is tetrabutylammonium bromide. The reaction temperature is 100°C to 200°C. In some embodiments, the reaction temperature is 150°C to 200°C. In some embodiments, the reaction temperature is 200°C. As an example, the reaction temperature may be, but is not limited to, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C. The reaction pressure is 4MPa to 10MPa. As an example, the reaction pressure may be, but is not limited to, 4MPa, 5MPa, 6MPa, 7MPa, 8MPa, 9MPa, 10MPa.

[0031] The processing temperature of the thin film evaporator is 100° C. to 200° C., and as an example, the processing temperature may be, but is not limited to, 100° C., 110° C., 120° C., 130° C., 140° C., 150° C., 160° C., 170° C., 180° C., 190° C., 200° C. The processing pressure is 1 kPa to 10 kPa, and as an example, the processing pressure may be, but is not limited to, 1 kPa, 2 kPa, 3 kPa, 4 kPa, 5 kPa, 6 kPa, 7 kPa, 8 kPa, 9 kPa, 10 kPa.

[0032] The recovery of some ethylene carbonate accounts for 0% to 100% of the total amount of ethylene carbonate. As an example, the recovery of some ethylene carbonate accounts for 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% of the total amount of ethylene carbonate, but is not limited to this. Other values ​​not listed within the scope of the present invention are also applicable.

[0033] In step (2), the functional monomer raw material is selected from hydroquinone or hexamethylenediamine. The reaction temperature is 100°C to 200°C. In some embodiments, the reaction temperature is 150°C to 200°C. In some embodiments, the reaction temperature is 200°C. As an example, the reaction temperature can be, but is not limited to, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C. The reaction pressure is 100kPa to 101.325kPa.

[0034] The temperature of the cooling treatment is 40°C to 95°C. As an example, the temperature of the cooling treatment can be, but not limited to, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, and 95°C. The temperature of the heating treatment is 98°C to 110°C. As an example, the temperature of the heating treatment can be, but not limited to, 98°C, 99°C, 100°C, 101°C, 102°C, 103°C, 104°C, 105°C, 106°C, 107°C, 108°C, 109°C, and 110°C.

[0035] The amount of carbon dioxide recovered accounts for 0% to 5% of the sum of the feed amounts of ethylene oxide, carbon dioxide and alkaline catalyst. As an example, the amount of carbon dioxide recovered accounts for 0%, 1%, 2%, 3%, 4%, 5% of the sum of the feed amounts of ethylene oxide, carbon dioxide and alkaline catalyst, but is not limited thereto, and other values ​​not listed within the scope of the present invention are equally applicable. The amount of alkaline catalyst recovered accounts for 0% to 5% of the sum of the feed amounts of ethylene oxide, carbon dioxide and alkaline catalyst. As an example, the amount of alkaline catalyst recovered accounts for 0%, 1%, 2%, 3%, 4%, 5% of the sum of the feed amounts of ethylene oxide, carbon dioxide and alkaline catalyst, but is not limited thereto, and other values ​​not listed within the scope of the present invention are equally applicable.

[0036] In order to better illustrate the purpose, technical scheme and beneficial effects of the present invention, the combined production device and process of ethylene carbonate and polyurethane chain extender of the present invention will be further described in conjunction with specific embodiments. It should be noted that the implementation methods of the following embodiments are further explanations of the present invention and should not be used as limitations of the present invention.

[0037] Example 1 This embodiment provides a combined production process of ethylene carbonate and polyurethane chain extender, comprising the steps of: (1) 2756 kg / h of ethylene oxide, 3380 kg / h of carbon dioxide and 26 kg / h of tetrabutylammonium bromide are respectively introduced into an ethylene carbonate reactor from the inlet of the ethylene carbonate reactor, and reacted at a temperature of 200° C. and a pressure of 10 MPa. The finished product mixture is introduced into a thin film evaporator from the outlet of the ethylene carbonate reactor, and treated at a temperature of 130° C. and a pressure of 2 kPa. 99.8% of ethylene carbonate (with a flow rate of 5541 kg / h) is extracted from the outlet of the first gas phase, and further distilled to obtain an electronic grade ethylene carbonate product or an industrial grade ethylene carbonate product; (2) Tetrabutylammonium bromide and the remaining part of ethylene carbonate (the flow rate of tetrabutylammonium bromide is 26 kg / h, and the flow rate of ethylene carbonate is 174 kg / h) enter the polyurethane chain extender reactor through the first liquid phase outlet, and hydroquinone (the flow rate is 53.75 kg / h) enters the polyurethane chain extender reactor through the second inlet, and reacts at a temperature of 160°C to obtain carbon dioxide and hydroquinone dihydroxyethyl ether. The carbon dioxide (the flow rate is 43.0 kg / h) is output through the second gas phase outlet and returned to the inlet of the ethylene carbonate reactor after compression for recycling. Hydroquinone dihydroxyethyl ether, tetrabutylammonium bromide and ethylene carbonate (the flow rate of hydroquinone dihydroxyethyl ether is 96.75 kg / h, the flow rate of tetrabutylammonium bromide is 26 kg / h, and the flow rate of ethylene carbonate is 88 kg / h) enter the crystallization kettle through the second liquid phase outlet; the crystallization kettle is first cooled to 60°C to allow the hydroquinone to react with the carbon dioxide. Hydroquinone dihydroxyethyl ether is crystallized, tetrabutylammonium bromide and unreacted ethylene carbonate (tetrabutylammonium bromide 25.85 kg / h, ethylene carbonate flow rate 87.5 kg / h) are output through the third liquid phase outlet and enter the inlet of the ethylene carbonate reactor for recycling, and then the crystallization kettle is heated to 110°C to melt the hydroquinone dihydroxyethyl ether, which is extracted through the fourth liquid phase outlet and further refined to obtain hydroquinone dihydroxyethyl ether with a purity of 99.3%.

[0038] Example 2 This embodiment provides a combined production process of ethylene carbonate and polyurethane chain extender, comprising the steps of: (1) 2756 kg / h of ethylene oxide, 3380 kg / h of carbon dioxide and 26 kg / h of tetrabutylammonium bromide are respectively introduced into an ethylene carbonate reactor from the inlet of the ethylene carbonate reactor, and reacted at a temperature of 200° C. and a pressure of 10 MPa. The finished product mixture is introduced into a thin film evaporator from the outlet of the ethylene carbonate reactor, and treated at a temperature of 130° C. and a pressure of 2 kPa. 99.8% of ethylene carbonate (with a flow rate of 5541 kg / h) is extracted from the outlet of the first gas phase, and further distilled to obtain an electronic grade ethylene carbonate product or an industrial grade ethylene carbonate product; (2) Tetrabutylammonium bromide and the remaining part of ethylene carbonate (tetrabutylammonium bromide flow rate is 26 kg / h, ethylene carbonate flow rate is 174 kg / h) enter the polyurethane chain extender reactor through the first liquid phase outlet, 1,6-hexanediamine (flow rate is 56.68 kg / h) enters the polyurethane chain extender reactor through the second inlet, and reacts at a temperature of 160°C to obtain carbon dioxide and 1,6-bis(2-hydroxy-ethoxycarbonylamine)hexane. Carbon dioxide (flow rate of 43.0 kg / h) is outputted from the second gas phase outlet and returned to the inlet of the ethylene carbonate reactor for recycling after compression. 1,6-bis(2-hydroxy-ethoxycarbonylamine)hexane, tetrabutylammonium bromide and ethylene carbonate (1,6-bis(2-hydroxy-ethoxycarbonylamine)hexane flow rate of 96.75 kg / h, tetrabutylammonium bromide flow rate of 26 kg / h, ethylene carbonate flow rate of 88 kg / h) enter the crystallization kettle through the second liquid phase outlet; the crystallization kettle is first cooled to 60°C to allow 1,6-bis(2-hydroxy-ethoxycarbonylamine)hexane to react with the ethylene carbonate. (2-Hydroxy-ethoxycarbonylamine)hexane is crystallized, tetrabutylammonium bromide and unreacted ethylene carbonate (tetrabutylammonium bromide 25.85 kg / h, ethylene carbonate flow rate 87.5 kg / h) are output through the third liquid phase outlet and enter the inlet of the ethylene carbonate reactor for recycling, and then the crystallization kettle is heated to 110°C to melt 1,6-bis(2-hydroxy-ethoxycarbonylamine), which is extracted through the fourth liquid phase outlet and further refined to obtain 1,6-bis(2-hydroxy-ethoxycarbonylamine)hexane with a purity of 98.9%.

[0039] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0040] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A device for producing ethylene carbonate and polyurethane chain extender, comprising a device body, characterized in that: The device body includes a first raw material transportation unit, a vinyl carbonate reactor, a thin film evaporator, a second raw material transportation unit, a polyurethane chain extender reactor and a crystallization kettle, wherein the outlet end of the first raw material transportation unit is connected to the inlet end of the vinyl carbonate reactor, the outlet end of the vinyl carbonate reactor is connected to the inlet end of the thin film evaporator, the thin film evaporator includes a first liquid phase outlet end and a first gas phase outlet end, the first liquid phase outlet end is connected to the first inlet end of the polyurethane chain extender reactor, and the first gas phase outlet end is used to produce vinyl carbonate; the outlet end of the second raw material transportation unit is connected to the second inlet end of the polyurethane chain extender reactor, the polyurethane chain extender reactor includes a second liquid phase outlet end and a second gas phase outlet end, the crystallization kettle includes a third liquid phase outlet end and a fourth liquid phase outlet end, the second liquid phase outlet end is connected to the inlet end of the crystallization kettle, the second gas phase outlet end and the third liquid phase outlet end are both connected to the inlet end of the vinyl carbonate reactor, and the fourth liquid phase outlet end is used to produce the polyurethane chain extender.

2. The combined production device of ethylene carbonate and polyurethane chain extender according to claim 1, characterized in that: The first raw material transport unit includes an ethylene oxide delivery pipe, a carbon dioxide delivery pipe and an alkaline catalyst delivery pipe, and the ethylene oxide delivery pipe, the carbon dioxide delivery pipe and the alkaline catalyst delivery pipe are respectively connected to the inlet end of the ethylene carbonate reactor through pipelines.

3. The combined production device of ethylene carbonate and polyurethane chain extender according to claim 1, characterized in that: The second raw material transport unit comprises a functional monomer transport pipe, and the functional monomer transport pipe is connected to the second inlet end of the polyurethane chain extender reactor.

4. The combined production device of ethylene carbonate and polyurethane chain extender according to claim 1, characterized in that: A compression device is also provided between the second gas phase outlet and the inlet of the ethylene carbonate reactor to pressurize and liquefy the carbon dioxide for recycling.

5. A combined production process of ethylene carbonate and polyurethane chain extender, characterized in that: The combined production device of ethylene carbonate and polyurethane chain extender according to any one of claims 1 to 4 comprises the following steps: (1) Ethylene oxide, carbon dioxide and alkaline catalyst are introduced into the ethylene carbonate reactor in a certain proportion for reaction, and the finished mixture is introduced into the thin film evaporator for treatment to extract part of the ethylene carbonate; (2) The remaining part of the ethylene carbonate, the alkaline catalyst, and the functional monomer raw material enter the polyurethane chain extender reactor for reaction, the generated carbon dioxide enters the ethylene carbonate reactor for recycling, the polyurethane chain extender, the alkaline catalyst, and the unreacted ethylene carbonate enter the crystallization kettle, firstly undergo a cooling treatment to allow the polyurethane chain extender to crystallize, the alkaline catalyst and the ethylene carbonate enter the ethylene carbonate reactor for recycling, and then undergo a heating treatment to extract the polyurethane chain extender.

6. The process for the combined production of ethylene carbonate and polyurethane chain extender according to claim 5, characterized in that: In step (1), the reaction temperature is 100°C to 200°C, the reaction pressure is 4MPa to 10MPa, the processing temperature of the thin film evaporator is 100°C to 200°C, and the processing pressure is 1kPa to 10kPa.

7. The process for the combined production of ethylene carbonate and polyurethane chain extender according to claim 5, characterized in that: In step (2), the reaction temperature is 100°C to 200°C, the reaction pressure is 100 kPa to 101.325 kPa, the temperature of the cooling treatment is 40°C to 95°C, and the temperature of the heating treatment is 98°C to 110°C.

8. The process for the combined production of ethylene carbonate and polyurethane chain extender according to claim 5, characterized in that: The alkaline catalyst is selected from ionic liquids, and the functional monomer raw material is selected from hydroquinone or hexamethylenediamine.

9. The process for the combined production of ethylene carbonate and polyurethane chain extender according to claim 5, characterized in that: The amount of carbon dioxide recovered accounts for 0% to 5% of the sum of the feed amounts of ethylene oxide, carbon dioxide and the alkaline catalyst, and the amount of alkaline catalyst recovered accounts for 0% to 5% of the sum of the feed amounts of ethylene oxide, carbon dioxide and the alkaline catalyst.

10. The process for the combined production of ethylene carbonate and polyurethane chain extender according to claim 5, characterized in that: In step (2), the carbon dioxide is pressurized and liquefied before entering the ethylene carbonate reactor.

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