A device and process for producing high purity methyl ethyl ether

Abstract

The application discloses a kind of equipment and process for producing high-purity methyl ether, it is related to the field of chemical compound synthesis, including reaction device, heating component, cold bath, crude product receiving tank, heavy component removal tower, light component removal tower, first reboiler, second reboiler, first condenser, second condenser, recovery tank, product receiving tank and controller, raw material sodium methoxide and halogenated ethane are directly reacted under anhydrous condition, without catalyst, to produce crude methyl ether, then crude methyl ether enters heavy component removal tower, and the gas of crude methyl ether with heavy components removed is detected by first online analysis detection component, and enters light component removal tower from the top of light component removal tower after passing the detection, for light component removal rectification, the gas phase impurities on the top of light component removal tower are analyzed by second online analysis detection component, and when passing the detection, methyl ether product enters product receiving tank, and then high-purity methyl ether product is produced by continuous rectification, so that product purity is high, reaction temperature is low, energy consumption is reduced, reaction yield is high, and production cost is low.

Description

Technical Field

[0001] This invention relates to the field of chemical compound synthesis, and in particular to an apparatus and process for producing high-purity methyl ethyl ether. Background Technology

[0002] Methyl ethyl ether is an organic compound with the chemical formula C3H8O. It is a colorless gas with a medicinal odor at room temperature and pressure, soluble in water, and miscible with ethanol and ether. It is mainly used as an anesthetic. The synthesis of symmetrical ethers such as methyl ether and diethyl ether can be easily achieved through catalytic dehydration of the corresponding alcohol, with high yields. However, asymmetrical ethers, also known as mixed ethers, require dehydration with corresponding mixed alcohols, resulting in lower yields.

[0003] One method involved synthesizing methyl ethyl ether using a mixture of methanol and ethanol as raw materials via a solid phosphoric acid catalyst. Equimolar amounts of methanol and ethanol were reacted over solid phosphoric acid catalyst at 336°C and 60 atm for 1.33 hours. The reaction equation was: CH3OH + C2H5OH → CH3OC2H5. The composition of the final product is shown in Table 1. Byproducts included ethylene, methyl ether, and diethyl ether.

[0004] Table 1. Experimental results of the synthesis of methyl ethyl ether from mixed alcohols

[0005] Dimethyl ether 18.4 grams Methyl ether 22.4 grams Diethyl ether 5.6 grams the remaining 1.6 grams Non-condensable gases 11.8 liters (22°C, 750 mmHg)

[0006] The advantage of this method is that the raw materials are readily available, consisting only of methanol and ethanol, and are inexpensive. However, the disadvantages are that the reaction temperature and pressure are very high, the yield is low, and the product contains many components, increasing the difficulty and cost of purification.

[0007] Another method is to form methyl ethyl ether (MEE) through ether exchange of a mixture of dimethyl ether and diethyl ether. Equimolar amounts of diethyl ether and dimethyl ether can also be heated in an autoclave at 150°C for 6 hours in the presence of a catalyst to obtain MEE. The reaction equation is: CH3OCH3 + C2H5OC2H5 → CH3OC2H5. The composition of the reactants is shown in Table 2 below.

[0008] Table 2. Experimental results of the synthesis of methyl ethyl ether from simple ethers.

[0009] ethylene 1.8 grams 0.06 Dimethyl ether 18.7 grams 0.41 Diethyl ether 27.5 grams 0.25 Methyl ether 15 grams 0.37

[0010] Both of these methods for synthesizing methyl ethyl ether have very low yields and are not suitable for large-scale production. Summary of the Invention

[0011] To address the above technical problems, this invention provides an equipment and process for producing high-purity methyl ethyl ether, which results in high product purity, low reaction temperature, reduced energy consumption, high reaction yield, and low production cost.

[0012] To achieve the above objectives, the present invention provides the following solution:

[0013] This invention provides equipment for producing high-purity methyl ethyl ether, comprising a reaction apparatus, a heating element, a cold bath, a crude product receiving tank, a heavy-weight removal tower, a light-weight removal tower, a first reboiler, a second reboiler, a first condenser, a second condenser, a recovery tank, a product receiving tank, and a controller. The crude product receiving tank is disposed in the cold bath, and the heating element is disposed in the crude product receiving tank. The reaction apparatus is connected to the crude product receiving tank via a first pipeline. The crude product receiving tank is connected to one side of the lower part of the heavy-weight removal tower via a second pipeline, on which a first regulating valve is installed. The first reboiler is disposed on the other side of the lower part of the heavy-weight removal tower. The top of the heavy-weight removal tower is connected to the first inlet of the first condenser via a third pipeline. The reflux port of the first condenser is connected to one side of the upper part of the heavy-weight removal tower via a first reflux pipeline. The first outlet of the first condenser is connected to one side of the light-weight removal tower via a fourth pipeline, on which a first online separator is installed. The system comprises an online analysis and detection component and a second regulating valve. The first online analysis and detection component is located at one end near the first outlet of the first condenser. A second reboiler is located on one side of the lower part of the light-light removal tower. The top of the light-light removal tower is connected to the first inlet of the second condenser via a fifth pipeline. The reflux port of the second condenser is connected to one side of the upper part of the light-light removal tower via a second reflux pipeline. The first outlet of the second condenser is connected to the recovery tank via a sixth pipeline. A second online analysis and detection component and a third regulating valve are located on the sixth pipeline. The second online analysis and detection component is located at one end near the light-light removal tower. The bottom of the light-light removal tower is connected to the product receiving tank via a seventh pipeline. A fourth regulating valve is located on the seventh pipeline. The first regulating valve, the second regulating valve, the third regulating valve, the fourth regulating valve, the first online analysis and detection component, and the second online analysis and detection component are all connected to the controller.

[0014] Preferably, the reaction apparatus includes a reaction vessel, a stirring paddle, a motor, and an elevated tank. The reaction vessel is equipped with a heating jacket. The stirring paddle is disposed inside the reaction vessel. The motor is disposed outside the top of the reaction vessel, and the power output shaft of the motor is connected to the stirring paddle. The elevated tank is disposed on one side outside the top of the reaction vessel and is connected to one side of the top of the reaction vessel via a connecting pipe. The other side of the top of the reaction vessel is connected to the top of the crude product receiving tank via the first pipe. The motor is connected to the controller.

[0015] Preferably, a first flow meter is installed on the second pipeline, a second flow meter is installed on the fourth pipeline, a third flow meter is installed on the sixth pipeline, a fourth flow meter is installed on the seventh pipeline, a fifth flow meter is installed on the first return pipeline, and a sixth flow meter is installed on the second return pipeline. The first flow meter, the second flow meter, the third flow meter, the fourth flow meter, the fifth flow meter, and the sixth flow meter are all connected to the controller.

[0016] Preferably, a first pressure sensor is provided at the top of the deweight removal tower, the second inlet of the first condenser is connected to the first refrigerant inlet pipe, a first refrigerant regulating valve is provided on the first refrigerant inlet pipe, and both the first pressure sensor and the first refrigerant regulating valve are connected to the controller.

[0017] Preferably, the system further includes a first heater and a first heat agent regulating valve. The inlet at the lower end of the first reboiler is connected to the bottom of the deweight removal tower via a first connecting pipe. The outlet at the upper end of the first reboiler is connected to one side of the lower part of the deweight removal tower via a second connecting pipe. A third pressure sensor is provided at the bottom of the deweight removal tower. The heat agent inlet and outlet of the first reboiler are connected via a first intermediate pipe. The first heater and the first heat agent regulating valve are provided on the first intermediate pipe. The first heat agent regulating valve is located between the heat agent inlet of the first reboiler and the first heater. The first heater, the first heat agent regulating valve, and the third pressure sensor are all connected to the controller.

[0018] Preferably, a second pressure sensor is provided at the top of the light-removal tower, the second inlet of the second condenser is connected to the second refrigerant inlet pipe, a second refrigerant regulating valve is provided on the second refrigerant inlet pipe, and both the second pressure sensor and the second refrigerant regulating valve are connected to the controller.

[0019] Preferably, the system further includes a second heater and a second heat agent regulating valve. The inlet at the lower end of the second reboiler is connected to the bottom of the light-duty removal tower via a third connecting pipe. The outlet at the upper end of the second reboiler is connected to one side of the lower part of the light-duty removal tower via a fourth connecting pipe. A fourth pressure sensor is installed at the bottom of the light-duty removal tower. The heat agent inlet and outlet of the second reboiler are connected via a second intermediate pipe. The second heater and the second heat agent regulating valve are installed on the second intermediate pipe. The second heat agent regulating valve is located between the heat agent inlet of the second reboiler and the second heater. The second heater, the second heat agent regulating valve, and the fourth pressure sensor are all connected to the controller.

[0020] Preferably, the system further includes a refrigeration cycle tank, a first cooling jacket, a third refrigerant inlet pipe, and a third condenser. The first cooling jacket is disposed outside the recovery tank, and the third condenser is disposed at the top of the recovery tank. The two ends of the third refrigerant inlet pipe are respectively connected to the bottom of the refrigeration cycle tank and the bottom of the first cooling jacket. The top of the first cooling jacket is connected to the inlet at the lower end of the third condenser. The outlet at the upper end of the third condenser is connected to the refrigeration cycle tank through a first outlet pipe. A third refrigerant regulating valve is disposed on the third refrigerant inlet pipe, and the third refrigerant regulating valve is connected to the controller.

[0021] Preferably, the system further includes a second cooling jacket, a fourth refrigerant inlet pipe, and a fourth condenser. The second cooling jacket is disposed outside the product receiving tank, and the fourth condenser is disposed at the top of the product receiving tank. The two ends of the fourth refrigerant inlet pipe are respectively connected to the bottom of the refrigeration cycle tank and the second cooling jacket. The top of the second cooling jacket is connected to the inlet at the lower end of the fourth condenser. The outlet at the upper end of the fourth condenser is connected to the refrigeration cycle tank through a second outlet pipe. A fourth refrigerant regulating valve is disposed on the fourth refrigerant inlet pipe, and the fourth refrigerant regulating valve is connected to the controller.

[0022] This invention also provides a process based on equipment for producing high-purity methyl ethyl ether, comprising the following steps:

[0023] Step 1: Under nitrogen protection, sodium methoxide is added to the reaction apparatus, followed by the addition of methanol as solvent. The mixture is heated to a temperature of 28°C-32°C, and ethane halide is added while stirring.

[0024] Step 2: The gas generated by the reaction enters the crude product receiving tank, and a refrigerant is added to the cold bath for cooling, so that the crude methyl ethyl ether gas is liquefied.

[0025] Step 3: After the crude product receiving tank has collected the product for a period of time, the refrigerant in the cold bath is removed, the first regulating valve is opened, and the heating element is turned on to raise the temperature and pressure. The crude methyl ethyl ether is forced into the heavy product removal tower by the pressure difference, and the first reboiler on the lower side of the heavy product removal tower starts to work to carry out heavy product removal distillation. The second regulating valve is opened, and the crude methyl ethyl ether gas with heavy components removed enters the first condenser from the top of the heavy product removal tower. The liquid material formed after cooling in the first condenser flows back to the upper part of the heavy product removal tower through the first reflux pipeline. After cooling, the remaining crude methyl ethyl ether gas with heavy components removed is detected as qualified by the first online analysis and detection element and enters the light product removal tower from the top. The second reboiler on the lower side of the light product removal tower starts to work to carry out light product removal distillation.

[0026] Step 4: Open the third regulating valve. The recovered product containing light components collected from the top of the light component removal tower enters the second condenser. After cooling in the second condenser, the resulting liquid material flows back to the upper part of the light component removal tower through the second reflux pipeline. The remaining recovered product containing light components after cooling enters the recovery tank. The gaseous impurities at the top of the light component removal tower are analyzed by the second online analysis and detection component. When the test is qualified, open the fourth regulating valve and close the third regulating valve, so that the methyl ethyl ether product enters the product receiving tank.

[0027] The present invention achieves the following technical effects compared to the prior art:

[0028] The equipment and process for producing high-purity methyl ethyl ether (ME) of this invention involve the direct reaction of sodium methoxide and haloethane under anhydrous conditions without a catalyst to produce crude ME. The crude ME then enters a heavy-weight removal tower. After passing inspection by a first online analytical detection unit, the crude ME gas, having lost its heavy components, enters a light-weight removal tower from the top for further distillation. A second online analytical detection unit analyzes the gaseous impurities at the top of the light-weight removal tower. Once the impurities are detected and deemed acceptable, the ME product enters a product receiving tank, where continuous distillation produces high-purity ME. The advantages of this invention include high product purity, low reaction temperature, reduced energy consumption, high reaction yield, and low production cost. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the equipment for producing high-purity methyl ethyl ether provided by the present invention.

[0031] Explanation of reference numerals in the attached drawings: 100. Equipment for producing high-purity methyl ethyl ether; 1. Reactor; 2. Heating jacket; 3. Motor; 4. Stirring paddle; 5. High-level tank; 6. Connecting pipeline; 7. First pipeline; 8. Crude product receiving tank; 9. Cold bath; 10. Heating component; 11. Second pipeline; 12. First regulating valve; 13. First flow meter; 14. De-weighting tower; 15. Third pipeline; 16. First condenser; 17. First reflux pipeline; 18. First pressure sensor; 19. First refrigerant regulating valve; 20. First reboiler; 21. First connecting pipe; 22. Second connecting pipe; 23. First intermediate pipe; 24. First heater; 25. First heat agent regulating valve; 26. Third pressure sensor; 27. Fourth pipeline; 28. First online analysis and detection component; 29. ​​Second flow meter; 3 0. Second regulating valve; 31. Lightweight refrigerant removal tower; 32. Fifth pipeline; 33. Second condenser; 34. Second reflux pipeline; 35. Second pressure sensor; 36. Second refrigerant regulating valve; 37. Sixth pipeline; 38. Second online analysis and detection component; 39. Third flow meter; 40. Third regulating valve; 41. Recovery tank; 42. First cooling jacket; 43. Third condenser; 44. Seventh pipeline; 45. Fourth flow meter; 46. Fourth regulating valve; 47. Product receiving tank; 48. Second cooling jacket; 49. Fourth condenser; 50. Second reboiler; 51. Third connecting pipe; 52. Fourth connecting pipe; 53. Second intermediate pipe; 54. Second heater; 55. Second refrigerant regulating valve; 56. Fourth pressure sensor; 57. Fifth flow meter; 58. Sixth flow meter. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] The purpose of this invention is to provide an equipment and process for producing high-purity methyl ethyl ether, which results in high product purity, low reaction temperature, reduced energy consumption, high reaction yield, and low production cost.

[0034] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1As shown, this embodiment provides a device 100 for producing high-purity methyl ethyl ether, including a reaction apparatus, a heating element 10, a cold bath 9, a crude product receiving tank 8, a heavy product removal tower 14, a light product removal tower 31, a first reboiler 20, a second reboiler 50, a first condenser 16, a second condenser 33, a recovery tank 41, a product receiving tank 47, and a controller. The crude product receiving tank 8 is disposed in the cold bath 9, and the heating element 10 is disposed in the crude product receiving tank 8. The reaction apparatus is connected to the crude product receiving tank 8 through a first pipeline 7. The cold bath 9 is used to hold refrigerant. The heating element 10 is used to increase the liquid temperature and pressure inside the crude product receiving tank 8, and the crude methyl ethyl ether is transported to the heavy product removal tower 14 by pressure difference.

[0036] The crude product receiving tank 8 is connected to one side of the lower part of the heavy component removal tower 14 via the second pipeline 11. The heavy component removal tower 14 is used to remove heavy components from the crude methyl ethyl ether. A first regulating valve 12 is installed on the second pipeline 11. A first reboiler 20 is installed on the other side of the lower part of the heavy component removal tower 14. The first reboiler 20 is used to heat the bottom of the heavy component removal tower 14. The top of the heavy component removal tower 14 is connected to the first inlet of the first condenser 16 via the third pipeline 15. The reflux port of the first condenser 16 is connected to one side of the upper part of the heavy component removal tower 14 via the first reflux pipeline 17. The first outlet of the first condenser 16 is connected to one side of the light component removal tower 31 via the fourth pipeline 27. A first online analysis and detection component 28 and a second regulating valve 30 are installed on the fourth pipeline 27. The first online analysis and detection component 28 is located at one end near the first outlet of the first condenser 16.

[0037] The light component removal tower 31 is used to remove light components from crude methyl ethyl ether. A second reboiler 50 is installed on one side of the lower part of the light component removal tower 31. The second reboiler 50 is used to heat the bottom of the light component removal tower 31. The top of the light component removal tower 31 is connected to the first inlet of the second condenser 33 through the fifth pipe 32. The reflux port of the second condenser 33 is connected to one side of the upper part of the light component removal tower 31 through the second reflux pipe 34. The first outlet of the second condenser 33 is connected to the recovery tank 41 through the sixth pipe 37. The recovery tank 41 is used to recover the gas emitted from the top of the second condenser 33. The sixth pipeline 37 is equipped with a second online analysis and detection component 38 and a third regulating valve 40. The second online analysis and detection component 38 is located at one end near the light-duty removal tower 31. The bottom of the light-duty removal tower 31 is connected to the product receiving tank 47 via the seventh pipeline 44. The product receiving tank 47 is used to receive methyl ethyl ether product. The seventh pipeline 44 is equipped with a fourth regulating valve 46. The first regulating valve 12, the second regulating valve 30, the third regulating valve 40, the fourth regulating valve 46, the first online analysis and detection component 28, and the second online analysis and detection component 38 are all connected to the controller.

[0038] Specifically, the reaction apparatus includes a reaction vessel 1, a stirring paddle 4, a motor 3, and an elevated tank 5. The reaction vessel 1 is equipped with a heating jacket 2. In this embodiment, the reaction vessel 1 is a glass reaction vessel 1 with a heating jacket 2. The heating jacket 2 is used to introduce warm water to heat the liquid in the reaction vessel 1. The stirring paddle 4 is located in the reaction vessel 1. The motor 3 is located outside the top of the reaction vessel 1. The power output shaft of the motor 3 is connected to the stirring paddle 4. The elevated tank 5 is located on one side outside the top of the reaction vessel 1. The elevated tank 5 is connected to one side of the top of the reaction vessel 1 through a connecting pipe 6. The elevated tank 5 is used to add haloethane. The other side of the top of the reaction vessel 1 is connected to the top of the crude product receiving tank 8 through a first pipe 7. The bottom of the crude product receiving tank 8 is connected to one side of the lower part of the de-weighting tower 14 through a second pipe 11. The motor 3 is connected to a controller. During the reaction, the controller controls the motor 3 to turn on so that the stirring paddle 4 can stir, thereby improving the reaction efficiency.

[0039] To enable intuitive monitoring of flow rate, a first flow meter 13 is installed on the second pipeline 11, a second flow meter 29 is installed on the fourth pipeline 27, a third flow meter 39 is installed on the sixth pipeline 37, a fourth flow meter 45 is installed on the seventh pipeline 44, a fifth flow meter 57 is installed on the first return pipeline 17, and a sixth flow meter 58 is installed on the second return pipeline 34. All of the first flow meter 13, the second flow meter 29, the third flow meter 39, the fourth flow meter 45, the fifth flow meter 57, and the sixth flow meter 58 are connected to the controller.

[0040] During operation, the first flow meter 13 is used to monitor the outflow rate of crude methyl ethyl ether gas, and works with the first regulating valve 12 to regulate the outflow rate of crude methyl ethyl ether; the second flow meter 29 is used to monitor the outflow rate of crude methyl ethyl ether gas after heavy component removal, and works with the second regulating valve 30 to regulate the outflow rate of crude methyl ethyl ether gas after heavy component removal; the third flow meter 39 is used to monitor the flow rate of the recovered product containing light components drawn from the top of the light component removal tower 31, and works with the third regulating valve 40 to regulate the flow rate of the recovered product containing light components; the fourth flow meter 45 is used to monitor the outflow rate of methyl ethyl ether product, and works with the fourth regulating valve 46 to regulate the outflow rate of methyl ethyl ether product; the fifth flow meter 57 is used to monitor the reflux flow rate of the heavy component removal tower 14; and the sixth flow meter 58 is used to monitor the reflux flow rate of the light component removal tower 31.

[0041] A first pressure sensor 18 is installed at the top of the de-refrigerant tower 14. The second inlet of the first condenser 16 is connected to the first refrigerant inlet pipe, and a first refrigerant regulating valve 19 is installed on the first refrigerant inlet pipe. The second inlet and second outlet of the first condenser 16 are used for the inflow and outflow of the refrigerant, respectively. Both the first pressure sensor 18 and the first refrigerant regulating valve 19 are connected to a controller. The first pressure sensor 18 and the first refrigerant regulating valve 19 work together to regulate the operating pressure at the top of the de-refrigerant tower 14.

[0042] This embodiment also includes a first heater 24 and a first heat agent regulating valve 25. The inlet at the lower end of the first reboiler 20 is connected to the bottom of the deweight removal tower 14 via a first connecting pipe 21, and the outlet at the upper end of the first reboiler 20 is connected to one side of the lower part of the deweight removal tower 14 via a second connecting pipe 22. A third pressure sensor 26 is installed at the bottom of the deweight removal tower 14. The heat agent inlet and outlet of the first reboiler 20 are connected via a first intermediate pipe 23. The first heater 24 and the first heat agent regulating valve 25 are installed on the first intermediate pipe 23. The first heat agent regulating valve 25 is located between the heat agent inlet of the first reboiler 20 and the first heater 24. The first heater 24, the first heat agent regulating valve 25, and the third pressure sensor 26 are all connected to a controller. The first heater 24, the first heat agent regulating valve 25, and the third pressure sensor 26 work together to regulate the operating pressure of the bottom of the deweight removal tower 14.

[0043] A second pressure sensor 35 is installed at the top of the light-weight refrigerant removal tower 31. The second inlet of the second condenser 33 is connected to the second refrigerant inlet pipe, and a second refrigerant regulating valve 36 is installed on the second refrigerant inlet pipe. The second inlet and second outlet of the second condenser 33 are used for the inflow and outflow of the refrigerant, respectively. Both the second pressure sensor 35 and the second refrigerant regulating valve 36 are connected to a controller. The second pressure sensor 35 and the second refrigerant regulating valve 36 work together to regulate the operating pressure at the top of the light-weight refrigerant removal tower 31.

[0044] This embodiment also includes a second heater 54 and a second heat agent regulating valve 55. The inlet at the lower end of the second reboiler 50 is connected to the bottom of the light-duty removal tower 31 via a third connecting pipe 51, and the outlet at the upper end of the second reboiler 50 is connected to one side of the lower part of the light-duty removal tower 31 via a fourth connecting pipe 52. A fourth pressure sensor 56 is installed at the bottom of the light-duty removal tower 31. The heat agent inlet and outlet of the second reboiler 50 are connected via a second intermediate pipe 53, on which the second heater 54 and the second heat agent regulating valve 55 are installed. The second heat agent regulating valve 55 is located between the heat agent inlet of the second reboiler 50 and the second heater 54. The second heater 54, the second heat agent regulating valve 55, and the fourth pressure sensor 56 are all connected to a controller. The second heater 54, the second heat agent regulating valve 55, and the fourth pressure sensor 56 work together to regulate the operating pressure of the bottom of the light-duty removal tower 31.

[0045] In this specific embodiment, the reboiler volume of the heavy weight removal tower 14 is 60L, the tower diameter is 108mm, the wall thickness is 6mm, the tower height is 14m, the packing height is 11.5m, and it uses 316L stainless steel random packing. The reboiler volume of the light weight removal tower 31 is 48L, the tower diameter is 89mm, the wall thickness is 5mm, the tower height is 12m, the packing height is 10m, and it uses 316L stainless steel random packing.

[0046] In this specific embodiment, both the first online analysis and detection component 28 and the second online analysis and detection component 38 are online gas chromatographs.

[0047] In this specific embodiment, the first regulating valve 12, the second regulating valve 30, the third regulating valve 40, and the fourth regulating valve 46 are all pneumatic regulating valves. To facilitate manual control of the extraction of crude methyl ethyl ether, a manual valve is provided on the second pipeline 11 in this embodiment.

[0048] This embodiment also includes a refrigeration circulation tank, a first cooling jacket 42, a third refrigerant inlet pipe, and a third condenser 43. The first cooling jacket 42 is disposed outside the recovery tank 41, and the third condenser 43 is disposed at the top of the recovery tank 41. The two ends of the third refrigerant inlet pipe are respectively connected to the bottom of the refrigeration circulation tank and the first cooling jacket 42. The top of the first cooling jacket 42 is connected to the inlet at the lower end of the third condenser 43, and the outlet at the upper end of the third condenser 43 is connected to the refrigeration circulation tank through a first outlet pipe. A third refrigerant regulating valve is provided on the third refrigerant inlet pipe, and the third refrigerant regulating valve is connected to a controller. By adjusting the third refrigerant regulating valve, the flow rate of the refrigerant entering the third cooling jacket is adjusted, thereby regulating the temperature and pressure of the recovery tank 41.

[0049] This embodiment also includes a second cooling jacket 48, a fourth refrigerant inlet pipe, and a fourth condenser 49. The second cooling jacket 48 is disposed outside the product receiving tank 47, and the fourth condenser 49 is disposed at the top of the product receiving tank 47. The two ends of the fourth refrigerant inlet pipe are respectively connected to the refrigeration circulation tank and the bottom of the second cooling jacket 48. The top of the second cooling jacket 48 is connected to the inlet at the lower end of the fourth condenser 49, and the outlet at the upper end of the fourth condenser 49 is connected to the refrigeration circulation tank through a second outlet pipe. A fourth refrigerant regulating valve is provided on the fourth refrigerant inlet pipe, and the fourth refrigerant regulating valve is connected to a controller. By adjusting the fourth refrigerant regulating valve, the flow rate of the refrigerant entering the fourth cooling jacket is adjusted, thereby regulating the temperature and pressure of the product receiving tank 47.

[0050] Specifically, the cold source of the refrigeration cycle tank, the first condenser 16 and the second condenser 33 is realized by a complete set of refrigeration units, the temperature is controllable, the operating temperature is 0℃~20℃, and the refrigerant is ethylene glycol aqueous solution. That is, the cold source equipment in this embodiment is simple to operate and the temperature control is stable.

[0051] This embodiment also provides a process based on equipment 100 for producing high-purity methyl ethyl ether, including the following steps:

[0052] Step 1: Under nitrogen protection, sodium methoxide is added to the reaction apparatus, followed by methanol as solvent. The mixture is heated to a temperature of 28°C-32°C. Halogenated ethane is then added with stirring. In this embodiment, sodium methoxide and halogenated ethane are used as raw materials to synthesize methyl ethyl ether, with methanol as the solvent. In this embodiment, water at 32°C-35°C is circulated through the heating jacket 2 to heat the raw materials in reactor 1.

[0053] Specifically, the molar ratio of sodium methoxide to haloethane is 1:1.2 to 1.3. From the perspective of product yield, this molar ratio can achieve the highest yield under the condition of lowest raw material cost.

[0054] Because the reaction is very slow when the material temperature is below 28°C, and increases with temperature above 32°C leading to an increase in the byproduct ethylene and a decrease in yield, the reaction temperature of sodium methoxide and haloethane in this embodiment is controlled between 28°C and 32°C, preferably between 29°C and 30°C. The haloethane can be bromoethane or chloroethane, with bromoethane being preferred.

[0055] Step 2: The gas generated in the reaction enters the crude product receiving tank 8, and is cooled by adding refrigerant to the cold bath 9, causing the crude methyl ethyl ether gas to liquefy. Specifically, for the reaction to proceed smoothly, the crude methyl ethyl ether gas generated in the reaction must be rapidly liquefied after entering the crude product receiving tank 8, maintaining a slightly positive pressure inside the crude product receiving tank 8. Dry ice is usually added to the cold bath 9. When the crude product receiving tank 8 is full of crude methyl ethyl ether, the reaction is stopped, and the crude methyl ethyl ether is transferred to the de-weighting tower 14 for low-temperature distillation. At this time, the dry ice needs to be removed.

[0056] Specifically, sodium methoxide is added to reactor 1 under nitrogen protection, followed by methanol. The raw materials in reactor 1 are stirred using a stirring paddle 4 at a speed of 4 to 5 r / min. While stirring, bromoethane is slowly added. When the concentration of bromoethane in the sodium methoxide solution reaches a certain level, the reaction begins, and gas is slowly released. The crude methyl ethyl ether gas enters the crude product receiving tank 8. Dry ice is added to the cold bath 9 outside the crude product receiving tank 8 for cooling. The crude methyl ethyl ether gas is liquefied in the crude product receiving tank 8 to obtain crude methyl ethyl ether.

[0057] In this specific embodiment, the 100L reactor 1 is purged with nitrogen to ensure that the reactor 1 is anhydrous. Under nitrogen protection, 60KG of a 50% (wt%) methanol solution of sodium methoxide is added, followed by 30L of dehydrated methanol. The heating jacket 2 is heated by circulating warm water, with the water temperature controlled at 32℃~35℃. The temperature of the sodium methoxide solution is maintained at 28℃~32℃. After the temperature is constant, stirring is started and 73.2KG of bromoethane (20% excess) is slowly added dropwise. The bromoethane is added to the high-level tank 5 by pressure difference, and the reaction continuously produces methyl ethyl ether gas.

[0058] When the reactants in reactor 1 were exhausted and no more gas was produced, collection was stopped. The experimental results showed that each reactor yielded 20.5 kg of methyl ethyl ether, a yield of 71%. This process was repeated three times. After the crude product in receiving tank 8 reached 61.5 kg, further distillation was carried out. Sampling analysis revealed that the crude methyl ethyl ether contained 0.1% ethylene, 2.58% bromoethane, 1.35% methanol, and 95.95% methyl ethyl ether.

[0059] Step 3: After collecting the crude product in the receiving tank 8 for a period of time, remove the refrigerant from the cold bath 9, open the first regulating valve 12, and turn on the heating element 10 to raise the temperature and pressure, so that the pressure inside the crude product receiving tank 8 reaches 0.3 MPa. The crude methyl ethyl ether is then forced into the de-heavy distillation tower 14 by the pressure difference. The first reboiler 20 on one side of the lower part of the de-heavy distillation tower 14 starts working to perform de-heavy distillation, which mainly removes heavy components such as bromoethane and methanol impurities. Then, open the second regulating valve 30, and the crude methyl ethyl ether gas, now free of heavy components, exits from the de-heavy distillation tower 14. The top of column 4 enters the first condenser 16. After cooling in the first condenser 16, the resulting liquid material is returned to the upper part of the heavy component removal tower 14 through the first reflux pipe 17. The remaining crude methyl ethyl ether gas, after being removed from heavy components, is detected and qualified by the first online analysis and detection unit 28 and enters the light component removal tower 31 from the top. Meanwhile, the second reboiler 50 on the lower side of the light component removal tower 31 starts working to carry out light component removal distillation. The light component removal distillation mainly removes ethylene and air components such as N2, O2, CO2, CO, and CH4. Specifically, the first online analysis and detection unit 28 analyzes the gaseous impurities at the top of the heavy component removal tower 14. When the impurities bromoethane and methanol are qualified, they are continuously collected and enter the light component removal tower 31, with the reflux ratio controlled at 15-20:1.

[0060] In this embodiment, the heating component 10 in the crude product receiving tank 8 is a heating coil. A heating agent is introduced into the heating coil at a temperature of 40°C to 45°C, thereby increasing the liquid temperature and pressure inside the crude product receiving tank 8, so as to facilitate the distillation and purification of the crude methyl ethyl ether into the de-weighting tower 14.

[0061] It should be noted that the crude product receiving tank 8 can be set up in two sets. When the first set is full, the other set can be activated, which is more convenient for operation.

[0062] Specifically, the heating temperature of the first reboiler 20 is controlled to be 45℃~60℃ by controlling the first heater 24. The third pressure sensor 26 is used to monitor the bottom operating pressure of the deweight removal tower 14. The bottom operating pressure of the deweight removal tower 14 can be controlled by controlling the first heat transfer fluid regulating valve 25. The first condenser 16 uses an aqueous solution of ethylene glycol as the refrigerant, with the temperature controlled at 0℃~20℃ and the reflux ratio controlled at 15~20:1. The first pressure sensor 18 is used to monitor the top operating pressure of the deweight removal tower 14. The top operating pressure of the deweight removal tower 14 can be controlled by controlling the first refrigerant regulating valve 19. In this embodiment, the top temperature of the deweight removal tower 14 is 25℃~30℃, and the bottom operating pressure of the deweight removal tower 14 is controlled at 0.3MPa~0.35MPa. The top operating pressure is within 0.03MPa lower than the bottom operating pressure.

[0063] Specifically, the heating temperature of the second reboiler 50 is controlled to be 45℃~60℃ by controlling the second heater 54. The fourth pressure sensor 56 is used to monitor the bottom operating pressure of the light-light removal tower 31. The bottom operating pressure of the light-light removal tower 31 can be controlled by controlling the second refrigerant regulating valve 55. The second condenser 33 uses an aqueous solution of ethylene glycol as the refrigerant, with the temperature controlled at 0℃~20℃ and the reflux ratio controlled at 15~20:1. The second pressure sensor 35 is used to monitor the top operating pressure of the light-light removal tower 31. The top operating pressure of the light-light removal tower 31 can be controlled by controlling the second refrigerant regulating valve 36. In this embodiment, the top temperature of the light-light removal tower 31 is 20℃~25℃, and the bottom operating pressure of the light-light removal tower 31 is controlled at 0.2MPa~0.25MPa. The top operating pressure is within 0.03MPa lower than the bottom operating pressure.

[0064] In this specific embodiment, the pressure difference between the bottom operating pressure of the heavy removal tower 14 and the bottom operating pressure of the light removal tower 31 is about 0.1 MPa.

[0065] Step 4: Open the third regulating valve 40. The recovered product containing light components collected from the top of the light component removal tower 31 enters the second condenser 33. After cooling in the second condenser 33, the resulting liquid material flows back to the upper part of the light component removal tower 31 through the second reflux pipeline 34. The remaining recovered product containing light components after cooling enters the recovery tank 41. The recovered product containing light components can undergo secondary distillation. The gaseous impurities at the top of the light component removal tower 31 are analyzed by the second online analysis and detection component 38. When the detection is qualified, that is, when the impurities ethylene and air components N2, O2, CO2, CO, and CH4 are qualified, the fourth regulating valve 46 is opened and the third regulating valve 40 is closed, so that the methyl ethyl ether product enters the product receiving tank 47. The purity of the obtained methyl ethyl ether product is 99.95% to 99.99%. Specifically, the composition of methyl ethyl ether is as follows: methanol < 50 ppm, bromoethane < 30 ppm, N2 < 3 ppm, O2 < 0.5 ppm, CO2 < 0.5 ppm, CO < 0.5 ppm, CH4 < 0.5 ppm, and methyl ethyl ether > 99.99%.

[0066] In this specific embodiment, the pressure difference between the light removal tower 31 and the recovery tank 41 and the product receiving tank 47 is 0.03MPa to 0.05MPa, thereby ensuring the continuity of the entire process.

[0067] In this embodiment, sodium methoxide and haloethane react directly under anhydrous conditions without a catalyst to produce crude methyl ethyl ether (MEE). The crude MEE then enters a heavy component removal tower 14. After passing the first online analysis and detection unit 28, the gaseous MEE gas, having lost its heavy components, enters a light component removal tower 31 from the top for light component removal distillation. The second online analysis and detection unit 38 analyzes the gaseous impurities at the top of the light component removal tower 31. Once the impurities are detected and passed, the MEE product enters a product receiving tank 47. Continuous distillation then produces a high-purity MEE product, resulting in high product purity, low reaction temperature, reduced energy consumption, high reaction yield, and low production cost. Therefore, this embodiment uses low-toxicity, low-corrosive raw materials and obtains a high-yield final product, MEE, through the Williamson reaction. The synthesis conditions are mild, the method is simple and easy to implement, and it is conducive to the large-scale production of MEE.

[0068] This specification uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An apparatus for producing high-purity methyl ethyl ether, characterized in that, The system includes a reaction apparatus, a heating element, a cold bath, a crude product receiving tank, a heavy product removal tower, a light product removal tower, a first reboiler, a second reboiler, a first condenser, a second condenser, a recovery tank, a product receiving tank, and a controller. The crude product receiving tank is located in the cold bath, and the heating element is located in the crude product receiving tank. The reaction apparatus is connected to the crude product receiving tank via a first pipeline. The crude product receiving tank is connected to one side of the lower part of the heavy product removal tower via a second pipeline, on which a first regulating valve is installed. The first reboiler is located on the other side of the lower part of the heavy product removal tower. The top of the heavy product removal tower is connected via a third... The pipeline is connected to the first inlet of the first condenser. The reflux port of the first condenser is connected to one side of the upper part of the heavy-duty removal tower via a first reflux pipeline. The first outlet of the first condenser is connected to one side of the light-duty removal tower via a fourth pipeline. The fourth pipeline is equipped with a first online analysis and detection component and a second regulating valve. The first online analysis and detection component is located at one end near the first outlet of the first condenser. A second reboiler is located on one side of the lower part of the light-duty removal tower. The top of the light-duty removal tower is connected to the first inlet of the second condenser via a fifth pipeline. The reflux port of the second condenser is connected to one side of the upper part of the light-duty removal tower via a second reflux pipeline. The first outlet of the second condenser is connected to the recovery tank via a sixth pipeline. The sixth pipeline is equipped with a second online analysis and detection component and a third regulating valve. The second online analysis and detection component is located at one end near the light-duty removal tower. The bottom of the light-duty removal tower is connected to the product receiving tank via a seventh pipeline. The seventh pipeline is equipped with a fourth regulating valve. The first regulating valve, the second regulating valve, the third regulating valve, the fourth regulating valve, the first online analysis and detection component, and the second online analysis and detection component are all connected to the... The controller is connected; it also includes a refrigeration cycle tank, a first cooling jacket, a third refrigerant inlet pipe, and a third condenser. The first cooling jacket is located outside the recovery tank, and the third condenser is located at the top of the recovery tank. The two ends of the third refrigerant inlet pipe are respectively connected to the bottom of the refrigeration cycle tank and the bottom of the first cooling jacket. The top of the first cooling jacket is connected to the inlet at the bottom of the third condenser. The outlet at the top of the third condenser is connected to the refrigeration cycle tank through a first outlet pipe. A third refrigerant regulating valve is provided on the third refrigerant inlet pipe, and the third refrigerant regulating valve is connected to the controller.It also includes a second cooling jacket, a fourth refrigerant inlet pipe, and a fourth condenser. The second cooling jacket is disposed outside the product receiving tank. The fourth condenser is disposed at the top of the product receiving tank. The two ends of the fourth refrigerant inlet pipe are respectively connected to the bottom of the refrigeration cycle tank and the second cooling jacket. The top of the second cooling jacket is connected to the inlet at the lower end of the fourth condenser. The outlet at the upper end of the fourth condenser is connected to the refrigeration cycle tank through a second outlet pipe. A fourth refrigerant regulating valve is disposed on the fourth refrigerant inlet pipe, and the fourth refrigerant regulating valve is connected to the controller.

2. The equipment for producing high-purity methyl ethyl ether according to claim 1, characterized in that, The reaction apparatus includes a reaction vessel, a stirring paddle, a motor, and an elevated tank. The reaction vessel is equipped with a heating jacket. The stirring paddle is disposed inside the reaction vessel. The motor is disposed outside the top of the reaction vessel, and the power output shaft of the motor is connected to the stirring paddle. The elevated tank is disposed on one side outside the top of the reaction vessel and is connected to one side of the top of the reaction vessel via a connecting pipe. The other side of the top of the reaction vessel is connected to the top of the crude product receiving tank via the first pipe. The motor is connected to the controller.

3. The equipment for producing high-purity methyl ethyl ether according to claim 1, characterized in that, A first flow meter is installed on the second pipeline, a second flow meter is installed on the fourth pipeline, a third flow meter is installed on the sixth pipeline, a fourth flow meter is installed on the seventh pipeline, a fifth flow meter is installed on the first return pipeline, and a sixth flow meter is installed on the second return pipeline. The first flow meter, the second flow meter, the third flow meter, the fourth flow meter, the fifth flow meter, and the sixth flow meter are all connected to the controller.

4. The equipment for producing high-purity methyl ethyl ether according to claim 1, characterized in that, The top of the deweight removal tower is equipped with a first pressure sensor, the second inlet of the first condenser is connected to the first refrigerant inlet pipe, the first refrigerant inlet pipe is equipped with a first refrigerant regulating valve, and both the first pressure sensor and the first refrigerant regulating valve are connected to the controller.

5. The equipment for producing high-purity methyl ethyl ether according to claim 1, characterized in that, It also includes a first heater and a first heat agent regulating valve. The inlet at the lower end of the first reboiler is connected to the bottom of the deweight removal tower through a first connecting pipe. The outlet at the upper end of the first reboiler is connected to one side of the lower part of the deweight removal tower through a second connecting pipe. A third pressure sensor is provided at the bottom of the deweight removal tower. The heat agent inlet and heat agent outlet of the first reboiler are connected through a first intermediate pipe. The first heater and the first heat agent regulating valve are provided on the first intermediate pipe. The first heat agent regulating valve is located between the heat agent inlet of the first reboiler and the first heater. The first heater, the first heat agent regulating valve, and the third pressure sensor are all connected to the controller.

6. The equipment for producing high-purity methyl ethyl ether according to claim 1, characterized in that, A second pressure sensor is installed at the top of the light-weight removal tower. The second inlet of the second condenser is connected to the second refrigerant inlet pipe. A second refrigerant regulating valve is installed on the second refrigerant inlet pipe. Both the second pressure sensor and the second refrigerant regulating valve are connected to the controller.

7. The equipment for producing high-purity methyl ethyl ether according to claim 1, characterized in that, It also includes a second heater and a second heat agent regulating valve. The inlet at the lower end of the second reboiler is connected to the bottom of the light-duty removal tower through a third connecting pipe. The outlet at the upper end of the second reboiler is connected to one side of the lower part of the light-duty removal tower through a fourth connecting pipe. A fourth pressure sensor is installed at the bottom of the light-duty removal tower. The heat agent inlet and outlet of the second reboiler are connected through a second intermediate pipe. The second heater and the second heat agent regulating valve are installed on the second intermediate pipe. The second heat agent regulating valve is located between the heat agent inlet of the second reboiler and the second heater. The second heater, the second heat agent regulating valve, and the fourth pressure sensor are all connected to the controller.

8. A process for producing high-purity methyl ethyl ether based on equipment according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Under nitrogen protection, sodium methoxide is added to the reaction apparatus, followed by the addition of methanol as solvent. The mixture is heated to a temperature of 28°C-32°C, and ethane halide is added while stirring. Step 2: The gas generated by the reaction enters the crude product receiving tank, and a refrigerant is added to the cold bath for cooling, so that the crude methyl ethyl ether gas is liquefied. Step 3: After the crude product receiving tank has collected the product for a period of time, the refrigerant in the cold bath is removed, the first regulating valve is opened, and the heating element is turned on to raise the temperature and pressure. The crude methyl ethyl ether is forced into the heavy product removal tower by the pressure difference, and the first reboiler on the lower side of the heavy product removal tower starts to work to carry out heavy product removal distillation. The second regulating valve is opened, and the crude methyl ethyl ether gas with heavy components removed enters the first condenser from the top of the heavy product removal tower. The liquid material formed after cooling in the first condenser flows back to the upper part of the heavy product removal tower through the first reflux pipeline. After cooling, the remaining crude methyl ethyl ether gas with heavy components removed is detected as qualified by the first online analysis and detection element and enters the light product removal tower from the top. The second reboiler on the lower side of the light product removal tower starts to work to carry out light product removal distillation. Step 4: Open the third regulating valve. The recovered product containing light components collected from the top of the light component removal tower enters the second condenser. After cooling in the second condenser, the resulting liquid material flows back to the upper part of the light component removal tower through the second reflux pipeline. The remaining recovered product containing light components after cooling enters the recovery tank. The gaseous impurities at the top of the light component removal tower are analyzed by the second online analysis and detection component. When the test is qualified, open the fourth regulating valve and close the third regulating valve, so that the methyl ethyl ether product enters the product receiving tank.

Images