A device for separating and purifying dibenzofuran

Abstract

This utility model relates to a dibenzofuran separation and purification device, including a distillation tank with a heater inside. The top and bottom of the distillation tank are respectively provided with a first discharge port and a second discharge port. A first feed port is provided on the side wall of the distillation tank. The device also includes a preheater, a toluene tank, a finished product tank, a first transfer pump, and a second transfer pump. The preheater has a second feed port and a third discharge port, and a first heat exchange coil is installed inside the preheater. The toluene tank has a third feed port and a fourth discharge port. The finished product tank has a fourth feed port and a fifth discharge port, and a second heat exchange coil is installed inside the finished product tank. The first feed port is connected to the third discharge port via a first pipeline. The first discharge port is connected to a main distillation pipe. The first transfer pump is installed on the main distillation pipe. The third and fourth feed ports are connected to the main distillation pipe via second and third pipelines, respectively. This utility model can improve the separation and purification efficiency and purity of dibenzofuran.

Description

Technical Field

[0001] This utility model relates to the field of dibenzofuran preparation technology, specifically to a dibenzofuran separation and purification device. Background Technology

[0002] Dibenzofuran is an excellent high-boiling-point organic solvent that can dissolve a variety of polymers. It can also be used as a raw material in pharmaceuticals, disinfectants, preservatives, fuels, synthetic resins, and high-temperature lubricants. Some derivatives of dibenzofuran possess anti-inflammatory, analgesic, muscle relaxant, and vasodilator activities. Furthermore, dibenzofuran can form eutectic mixtures with biphenyl for use as heat transfer solvents.

[0003] Currently, the main method for synthesizing dibenzofuran is to use diphenyl ether or 2-cyclohexenylcyclohexanone as raw materials and add them to the reaction solution under high pressure and temperature for oxidation synthesis. The dibenzofuran produced by this method still contains a small amount of toluene and complex residues, which need to be separated and purified. The existing method usually involves adding a catalyst to the dibenzofuran solution to precipitate the toluene and complex residues. This method has low separation and purification efficiency and low purity, and still needs to be improved. Utility Model Content

[0004] This invention addresses the shortcomings of existing technologies by providing a dibenzofuran separation and purification device, thereby improving separation and purification efficiency and purity.

[0005] This utility model is achieved through the following technical solution: a dibenzofuran separation and purification device, including a distillation tank, a heater inside the distillation tank, a first discharge port and a second discharge port respectively at the top and bottom of the distillation tank, a first feed port on the side wall of the distillation tank, and also including a preheater, a toluene tank, a finished product tank, a first transfer pump and a second transfer pump, the preheater having a second feed port and a third discharge port, a first heat exchange coil inside the preheater, the toluene tank having a third feed port and a fourth discharge port, the finished product tank having a fourth feed port and a fifth discharge port, and a second heat exchange coil inside the finished product tank;

[0006] The first feed inlet is connected to the third discharge outlet through the first pipeline. The first discharge outlet is connected to the main distillation pipe. The first delivery pump is installed on the main distillation pipe. The third feed inlet and the fourth feed inlet are connected to the main distillation pipe through the second pipeline and the third pipeline, respectively. The input end of the first heat exchange coil is connected to the output end of the second heat exchange coil through the fourth pipeline. The output end of the first heat exchange coil is connected to the input end of the second heat exchange coil through the fifth pipeline. The second delivery pump is installed on the fifth pipeline.

[0007] In this method, the dibenzofuran solution to be purified is added to a distillation tank. The solution is heated by a heater. Utilizing the different boiling points of dibenzofuran and toluene, by controlling different heating temperatures, the dibenzofuran and toluene evaporate and are stored separately in the product tank and toluene tank, respectively, thus purifying the dibenzofuran. The remaining complex residue in the distillation tank can be directly discharged. This method offers higher separation efficiency, higher purity after purification, and is convenient to operate. Furthermore, the high-temperature vaporized dibenzofuran enters the product tank and exchanges heat with the second heat exchange coil. A second transfer pump introduces a high-temperature heat exchange medium into the first heat exchange coil, where the high-temperature medium exchanges heat with the dibenzofuran solution in the preheater, achieving preheating of the dibenzofuran solution, reducing energy consumption, improving heating efficiency, and enhancing separation efficiency.

[0008] As an optimization, two heaters are symmetrically fixed to the inner wall of the distillation tank. This optimized solution heats the solution uniformly by using two symmetrically distributed heaters, thus improving uniformity.

[0009] As an optimization, multiple guide vanes are fixed inside the distillation tank, extending vertically and evenly distributed radially. This optimization increases the liquid-phase contact area and improves the steam heating area by using guide vanes, thereby enhancing separation efficiency.

[0010] As an optimization, the guide plate has a wave structure. This optimization further increases the heat contact area and improves the heating separation effect.

[0011] As an optimization, an acidification tank is also included. This tank has a fifth inlet and a sixth outlet. The second outlet is connected to a discharge pipe, which is connected to a sixth pipeline via a tee fitting. The sixth pipeline is connected to the fifth inlet. This optimized solution acidifies the residual compound in the acidification tank, regenerating it into a usable compound, thus saving resources.

[0012] As an optimization, the distillation tank is equipped with a temperature sensor and a pressure relief valve. This optimization scheme improves safety by using the temperature sensor to monitor the internal temperature in real time and the pressure relief valve to monitor the internal pressure in real time.

[0013] The beneficial effects of this invention are as follows: By heating the solution with a heater, and utilizing the different boiling points of dibenzofuran and toluene, different heating temperatures are controlled so that the dibenzofuran and toluene evaporate and are stored separately in the finished product tank and toluene tank, respectively, thus purifying the dibenzofuran. The remaining complex residue in the distillation tank can be directly discharged. This method offers higher separation efficiency, higher purity after purification, and convenient operation. Furthermore, the high-temperature vaporized dibenzofuran enters the finished product tank and exchanges heat with the second heat exchange coil. A second transfer pump introduces a high-temperature heat exchange medium into the first heat exchange coil, where the high-temperature medium exchanges heat with the dibenzofuran solution in the preheater, achieving preheating of the dibenzofuran solution, reducing energy consumption, improving heating efficiency, and enhancing separation efficiency. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the process of this utility model;

[0015] Figure 2 This is a cross-sectional view of a distillation jar;

[0016] As shown in the figure:

[0017] 1. Pressure relief valve; 2. Temperature sensor; 3. Distillation tank; 4. Distillation main pipe; 5. First transfer pump; 6. Valve; 7. First pipeline; 8. Preheater; 9. First heat exchange coil; 10. Feed pipe; 11. Toluene discharge pipe; 12. Toluene tank; 13. Second pipeline; 14. Third pipeline; 15. Finished product tank; 16. Second heat exchange coil; 17. Second transfer pump; 18. Fifth pipeline; 19. Fourth pipeline; 20. Heat exchange medium inlet pipe; 21. Dibenzofuran discharge pipe; 22. Sixth pipeline; 23. Acidification tank; 24. Complex discharge pipe; 25. Heater; 26. Baffle plate; 27. Discharge pipe. Detailed Implementation

[0018] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0019] like Figures 1-2 As shown, a dibenzofuran separation and purification device includes a distillation tank 3, a preheater 8, a toluene tank 12, a finished product tank 15, a first transfer pump 5, and a second transfer pump 17. The distillation tank 3 is equipped with heaters 25. In this embodiment, two heaters 25 are symmetrically fixed to the inner wall of the distillation tank 3. The dibenzofuran solution is heated by the two symmetrically distributed heaters 25, ensuring uniform heating and improving homogeneity.

[0020] Multiple guide plates 26 are fixedly installed inside the distillation tank 3. The guide plates 26 extend vertically, are parallel to each other, and are evenly distributed radially along the distillation tank 3. The guide plates 26 have a wave-like structure. The guide plates 26 increase the liquid phase contact area, improve the steam heating area, and enhance the separation efficiency and heating separation effect.

[0021] The distillation tank 3 is equipped with a temperature sensor 2 and a pressure relief valve 1. The temperature sensor 2 monitors the internal temperature in real time, and the pressure relief valve 1 monitors the internal pressure in real time, thereby improving safety.

[0022] The distillation tank 3 has a first discharge port and a second discharge port at its top and bottom, respectively, and a first feed port on its side wall.

[0023] The preheater 8 is provided with a second inlet and a third outlet, and a first heat exchange coil 9 is fixedly installed inside the preheater 8.

[0024] The toluene tank 12 is provided with a third inlet and a fourth outlet.

[0025] The finished product tank 15 is provided with a fourth inlet and a fifth outlet, and a second heat exchange coil 16 is fixedly installed inside the finished product tank 15.

[0026] Specifically, the first inlet is connected to the third outlet via the first pipeline 7, and the second inlet is connected to a feed pipe 10, on which a valve 6 is installed. The dibenzofuran solution to be purified is added to the preheater 8 for preheating through the feed pipe 10, and then enters the distillation tank 3 for heating and distillation through the first inlet via the first pipeline 7.

[0027] The first discharge port is connected to a distillation main pipe 4, and a first delivery pump 5 is installed on the distillation main pipe 4. A valve 6 is installed on the distillation main pipe 4. In this embodiment, the first delivery pump 5 is a vacuum pump, which draws the steam separated by heating in the distillation tank 3 into the distillation main pipe 4.

[0028] The third and fourth feed inlets are connected to the main distillation pipe 4 via the second pipe 13 and the third pipe 14, respectively. In this embodiment, both the second pipe 13 and the third pipe 14 are connected to the main distillation pipe 4 via tee fittings, and valves 6 are installed on both the second pipe 13 and the third pipe 14. The toluene vapor separated by distillation enters the toluene tank 12 for storage through the second pipe 13. The dibenzofuran vapor separated by distillation enters the finished product tank 15 for storage through the third pipe 14.

[0029] The fourth discharge port is connected to a toluene discharge pipe 11, and a valve 6 is installed on the toluene discharge pipe 11 to discharge the toluene stored in the toluene tank 12.

[0030] The fifth discharge port is connected to a dibenzofuran discharge pipe 21, and a valve 6 is installed on the dibenzofuran discharge pipe 21 to discharge the dibenzofuran stored in the finished product tank 15.

[0031] The input end of the first heat exchange coil 9 is connected to the output end of the second heat exchange coil 16 through the fourth pipe 19. In this embodiment, the fourth pipe 19 is connected to the heat exchange medium inlet pipe 20 through a tee fitting. A valve 6 is installed on the heat exchange medium inlet pipe 20, and the heat exchange medium is added into the fourth pipe 19 through the heat exchange medium inlet pipe 20.

[0032] The output end of the first heat exchange coil 9 is connected to the input end of the second heat exchange coil 16 through the fifth pipeline 18. The second delivery pump 17 is installed on the fifth pipeline 18. In this embodiment, the second delivery pump 17 is a circulation pump, and a valve 6 is installed on the fifth pipeline 18. Through the pumping of the second delivery pump 17, the heat exchange medium is circulated between the first heat exchange coil 9 and the second heat exchange coil 16 for heat exchange.

[0033] The high-temperature dibenzofuran vapor in the finished product tank 15 exchanges heat with the second heat exchange coil 16 for cooling. The high-temperature heat exchange medium is introduced into the first heat exchange coil 9 through the second transfer pump 17. The high-temperature heat exchange medium exchanges heat with the dibenzofuran solution in the preheater 8 to achieve preheating of the dibenzofuran solution, reduce energy consumption, improve heating efficiency, and improve separation efficiency.

[0034] The system also includes an acidification tank 23, which has a fifth inlet and a sixth outlet. The second outlet is connected to a discharge pipe 27, which is connected to a sixth pipe 22 via a tee fitting. The sixth pipe 22 is connected to the fifth inlet. In this embodiment, the sixth outlet is connected to a compound discharge pipe 24. Valves 6 are installed on the discharge pipe 27, the sixth pipe 22, and the compound discharge pipe 24. The acidification tank 23 acidifies the compound residue, regenerating it into a usable compound, thus saving resources. The acid washing and regeneration of the compound residue using the acidification tank 23 in this embodiment is existing technology and will not be described in detail here.

[0035] Working principle: The dibenzofuran solution to be purified is added to the preheater 8 through the feed pipe 10 and enters the distillation tank 3 through the first pipeline 7. The dibenzofuran solution is heated by the heater 25.

[0036] First, open valve 6 of the second pipeline 13 and close valve 6 of the third pipeline 14. Control the heating temperature gradient of heater 25 to rise to 180°C. At this time, toluene reaches its boiling point and forms toluene vapor. Maintain this temperature and continue heating for 0.5~1h to ensure that all the small amount of toluene remaining in the solution is distilled into toluene vapor. The vapor is then pumped by the first transfer pump 5 through the second pipeline 13 into the toluene tank 12 for storage and cooling into a liquid state. Finally, it is discharged and collected through the toluene discharge pipe 11.

[0037] Then, valve 6 of the second shut-off line is closed, and valve 6 of the third pipeline 14 is opened, controlling the heating temperature gradient of heater 25 to rise to 285℃. At this point, dibenzofuran reaches its boiling point and forms dibenzofuran vapor. This temperature is maintained for 2-3 hours of continuous heating. The dibenzofuran vapor is pumped by the first transfer pump 5 through the third pipeline 14 into the finished product tank 15 for storage. At this time, the high-temperature dibenzofuran vapor exchanges heat with the heat exchange medium in the second heat exchange coil 16, causing the dibenzofuran vapor to cool and purify into a liquid state rapidly. The heat exchange medium forms a high-temperature heat exchange medium, which is pumped to the first heat exchange coil 9 by the second transfer pump 17. This facilitates the use of residual heat for the dibenzofuran solution that subsequently passes through the preheater 8, reducing energy consumption and improving heating and separation efficiency. The liquid dibenzofuran is discharged and collected through the dibenzofuran discharge pipe 21.

[0038] The remaining PEG-400 complex residue in the distillation tank 3 enters the acidification tank 23 through the discharge pipe 27. After acid washing, the PEG-400 complex can be regenerated and collected for reuse.

[0039] Of course, the above description is not limited to the examples above. Technical features of this utility model not described can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. A dibenzofuran separation and purification apparatus, comprising a distillation tank (3), a heater (25) provided inside the distillation tank (3), a first discharge port and a second discharge port respectively provided at the top and bottom of the distillation tank (3), and a first feed port provided on the side wall of the distillation tank (3), characterized in that: Also include preheater (8), toluene tank (12), finished product tank (15), first delivery pump (5) and second delivery pump (17), the preheater (8) is equipped with second feed port and third discharge port, first heat exchange coil (9) is arranged in preheater (8), the toluene tank (12) is equipped with third feed port and fourth discharge port, the finished product tank (15) is equipped with fourth feed port and fifth discharge port, second heat exchange coil (16) is arranged in finished product tank (15); The first feed port is communicated with the third discharge port by first pipeline (7), and the first discharge port is connected with distillation main pipe (4), and the first delivery pump (5) is installed on the distillation main pipe (4), the third feed port and the fourth feed port are communicated with the distillation main pipe (4) by second pipeline (13) and third pipeline (14) respectively, the input end of the first heat exchange coil (9) is communicated with the output end of the second heat exchange coil (16) by fourth pipeline (19), the output end of the first heat exchange coil (9) is communicated with the input end of the second heat exchange coil (16) by fifth pipeline (18), and the second delivery pump (17) is installed on the fifth pipeline (18).

2. The dibenzofuran separation and purification apparatus according to claim 1, characterized by: The inner wall of the distillation tank (3) is symmetrically provided with two heaters (25).

3. The dibenzofuran separation and purification apparatus according to claim 1, characterized by: A plurality of guide plates (26) are fixedly arranged in the distillation tank (3), the guide plates extend in the vertical direction, and the plurality of guide plates are uniformly distributed in the radial direction.

4. The dibenzofuran separation and purification apparatus according to claim 3, characterized by: The guide plate (26) is a wave structure.

5. The dibenzofuran separation and purification apparatus according to claim 1, characterized by: Also include acidification pool (23), acidification pool has fifth feed port and sixth discharge port, the second discharge port is connected with discharge pipe (27), the discharge pipe (27) is connected with sixth pipeline (22) through three-way pipe fitting, and the sixth pipeline (22) is communicated with the fifth feed port.

6. The dibenzofuran separation and purification apparatus according to claim 1, characterized by: The distillation tank (3) is provided with a temperature sensor (2) and a pressure relief valve (1).

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