Production method of perfluorotripropylamine

Abstract

The production method comprises the following steps: S1, adding a hydrogen fluoride solution into a tripropylamine solution, and mixing the hydrogen fluoride solution and the tripropylamine solution to form an electrolyte; s2, air in the electrolytic bath is replaced through inert gas, and mixed liquid is introduced into the electrolytic bath after replacement is completed; s3, low-voltage direct current is introduced for an electrolytic fluorination reaction; and S4, after electrolysis is completed, tripropylamine is converted into perfluoro tripropylamine through electrolytic fluorination, and discharging is conducted from the bottom of the electrolytic bath.

Description

Technical Field

[0001] The present invention relates to the technical field of perfluorotripropylamine preparation, and more particularly to a production method of perfluorotripropylamine. Background Art

[0002] Perfluorotripropylamine (PFTA) is completely non-toxic to the human body and can dissolve and carry large amounts of oxygen and carbon dioxide. It is a key component of artificial plasma, used in modern medicine. It is also used as an anti-corrosion transmission fluid for instrumentation, a dielectric insulation fluid, and a leak detector for electronic components and devices. Therefore, the production of PFTA is of great significance to scientific progress and development. Summary of the Invention

[0003] The object of the present invention is to overcome the above-mentioned deficiencies in the prior art and to provide a method for producing perfluorotripropylamine.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The present invention discloses a method for producing perfluorotripropylamine, comprising the following steps:

[0006] S1, adding hydrogen fluoride solution to tripropylamine solution and mixing the two to form an electrolyte;

[0007] S2, the air in the electrolytic cell is replaced by an inert gas, and after the replacement is completed, the mixed liquid is passed into the electrolytic cell;

[0008] S3, low voltage direct current is introduced to carry out electrolytic fluorination reaction; the reaction pressure is normal pressure;

[0009] S4, after the electrolysis is completed, tripropylamine is electrofluorinated and converted into perfluorotripropylamine, which is discharged from the bottom of the electrolytic cell.

[0010] Furthermore, the molar ratio of tripropylamine to hydrogen fluoride is 1:48 to 1:77.

[0011] Furthermore, the temperature is maintained at 10°C to 50°C during the electrolysis process.

[0012] Furthermore, the inert gas is nitrogen.

[0013] Furthermore, the voltage of the electrolysis reaction is 3V to 10V, and the current density is 5mA / cm 2 Up to 50mA / cm 2 .

[0014] Furthermore, the perfluorotripropylamine obtained in step S4 is separated to improve its purity.

[0015] Furthermore, the volatilized hydrogen fluoride is condensed by a condensation mechanism, and the condensed hydrogen fluoride liquid is reintroduced into the electrolytic cell.

[0016] The beneficial effects of the present invention are: high-purity perfluorotripropylamine can be produced by utilizing the electrochemical fluorination method; and volatilized hydrogen fluoride is condensed and recovered by a condensation mechanism, thereby reducing the loss of raw materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of a structure of the electrolytic cell in this embodiment;

[0018] Figure 2 Schematic diagram of a structure of the condensation mechanism in this embodiment;

[0019] Figure 3 for Figure 2 A magnified schematic diagram of point A in the middle;

[0020] Figure 4 Schematic diagram of the installation of the cooling pipe in this embodiment;

[0021] Figure 5 for Figure 4 A magnified schematic diagram of point A in the middle;

[0022] Figure 6 for Figure 4 A magnified schematic diagram of point B in the middle;

[0023] Figure 7 for Figure 4 Enlarged schematic diagram of point C in the middle.

[0024] Figure numerals: 1, electrolytic cell; 2, condensation mechanism; 3, feed pipe; 4, collecting pipe; 5, recessed portion; 6, heat shield; 7, cooling pipe; 8, cavity; 9, heat exchange chamber; 10, condenser; 11, input pipe; 12, output pipe; 13, return pipe; 14, spacer; 15, sealing valve 1; 16, cooling water inlet; 17, cooling water outlet; 18, limit plate; 19, valve block 1; 20, valve block 2; 21, valve seat; 22, spring 1; 23, mounting block; 24, guide rod; 25, spring 2; 26, guide wheel 1; 27, guide pipe; 28, mounting frame; 29, guide wheel 2; 30, connecting rope; 31, cooling section 1; 32. Partition; 33. Cooling section 2; 34. Water inlet ring 1; 35. Connecting pipe 1; 36. Telescopic pipe 1; 37. Water outlet ring 1; 38. Water inlet ring 2; 39. Telescopic pipe 2; 40. Connecting pipe 2; 41. Water outlet ring 2; 42. Rack 1; 43. Rack 2; 44. Drive shaft; 45. Drive gear; 46. Limit block; 47. Stop block; 48. Extension pipe 1; 49. Extension pipe 2; 50. Insert pipe; 51. Guide seat; 52. Sealing valve 2; 53. Spring 3; 54. Connecting hole 1; 55. Connecting pipe 1; 56. Sealing plate; 57. Connecting pipe 2; 58. Connecting hole 2; 59. Sealing ring; 60. Groove. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] A method for producing perfluorotripropylamine comprises the following steps:

[0027] S1. Adding a hydrogen fluoride solution to a tripropylamine solution and mixing the two to form an electrolyte; the molar ratio of tripropylamine to hydrogen fluoride is 1:48 to 1:77.

[0028] S2, the air in the electrolytic cell 1 is replaced by an inert gas, and after the replacement is completed, the mixed liquid is passed into the electrolytic cell 1 through the feed pipe 3. The inert gas is nitrogen

[0029] S3, low voltage direct current is applied to carry out electrolytic fluorination reaction; the voltage of the electrolytic reaction is 3V to 10V, and the current density is 5mA / cm 2 Up to 50mA / cm 2 The reaction pressure is normal pressure.

[0030] The temperature is maintained at 10°C to 50°C during the electrolysis process.

[0031] S4, after the electrolysis is completed, tripropylamine is electrofluorinated and converted into perfluorotripropylamine, which is discharged from the bottom of the electrolytic cell.

[0032] The perfluorotripropylamine obtained in step S4 is separated to improve the purity of the perfluorotripropylamine.

[0033] During the reaction, hydrogen fluoride volatilizes. If the volatilized hydrogen fluoride is directly treated as tail gas, it will actually cause great waste due to the large amount of volatilized hydrogen fluoride. The volatilized hydrogen fluoride is collected by the condensing mechanism 3, and the condensed hydrogen fluoride liquid is returned to the electrolytic cell 1 through the reflux pipe 13, reducing the loss of raw materials.

[0034] like Figure 1-Figure 7As shown, a condensing mechanism 2 and a feed pipe 3 are provided at the top of the electrolytic cell 1. The condensing mechanism 2 includes a collecting pipe 4, a heat exchange chamber 9, and a reflux pipe 13. The lower portion of the collecting pipe 4 is connected to the electrolytic cell 1, the heat exchange chamber 9 is connected to the collecting pipe 4, the reflux pipe 13 is connected to the end of the heat exchange chamber 9 away from the collecting pipe 4, and the lower end of the reflux pipe 13 is connected to the electrolytic cell 1. A plurality of recesses 5 are provided inside the collecting pipe 4. A cooling pipe 7 is provided on the outer periphery of the collecting pipe 4. The cooling pipe 7 is located within the recesses 5 and is connected to the cooling water inlet 16 and the cooling water outlet 17. A spacer 14 is provided at the top of the collecting pipe 4. A sealing valve 15 is provided on the spacer 14. The spacer 14 separates the collecting pipe 4 so that the upper portion of the collecting pipe 4 forms a cavity 8. The heat exchange chamber 9 is connected to the cavity 8. A condenser tube 10 is provided in the heat exchange chamber 9 . Both ends of the condenser tube 10 extend out of the heat exchange chamber 9 . Both ends of the condenser tube 10 are connected to an input tube 11 and an output tube 12 , respectively.

[0035] The volatilized hydrogen fluoride first enters the collection tube 4 and accumulates there. Cooling water is then injected into the cooling tube 7 through the cooling water inlet 16. The cooling tube 7, through contact heat exchange with the collection tube 4, causes the temperature inside the collection tube 4 to drop, causing the hydrogen fluoride to condense on the inner wall of the collection tube 4. The condensed hydrogen fluoride liquid can flow directly down along the inner wall of the collection tube 4 and return to the electrolytic cell 1. The cooling water inlet 16 and the cooling water outlet 17 are connected to an external cooling water mechanism, circulating cooling water into the cooling tube 7 to continuously condense the hydrogen fluoride in the collection tube 4. When the amount of hydrogen fluoride volatilized in the electrolytic cell 1 is large, the hydrogen fluoride in the collection tube 4 cannot condense in time, which will also increase the air pressure. The hydrogen fluoride will push open the sealing valve 15 and reach the chamber 8, and then enter the heat exchange chamber 9 connected to the chamber 8. Refrigerant is introduced into the condenser tube 10 to condense the hydrogen fluoride that has entered the heat exchange chamber 9. The bottom of the heat exchange chamber 9, near one end of the cavity 8, is higher than the bottom of the heat exchange chamber 9, near the end of the return pipe 13. This allows the condensed hydrogen fluoride liquid to flow along the inclined bottom of the heat exchange chamber 9 to the return pipe 13, and then flow back into the electrolytic cell 1 through the return pipe 13. This allows for supplementary condensation when hydrogen fluoride in the collection pipe 4 cannot be condensed in time, thereby avoiding the problem of excessive pressure in the electrolytic cell 1 caused by a large amount of volatilized hydrogen fluoride.

[0036] The condensed hydrogen fluoride liquid in the heat exchange chamber 9 refluxes through the reflux pipe 13 without interfering with the new hydrogen fluoride gas, thereby avoiding heat exchange between the hydrogen fluoride liquid and the new hydrogen fluoride gas.

[0037] The refrigerant may be a glycol-water mixture, a brine mixture, liquid nitrogen, etc., and the temperature of the refrigerant is controlled below 19°C.

[0038] like Figure 3As shown, a valve seat 21 is defined on the spacer 14. Sealing valve 15 comprises a stopper disc 18, valve block 19, and valve block 20, which are connected in sequence. Valve blocks 19 and 20 are located within the valve seat 21, with the stopper disc 18 positioned above the spacer 14. The outer peripheries of valve blocks 19 and 20 abut against the inner wall of the valve seat 21. The stopper disc 18 has a larger diameter than valve block 19, thus covering the upper opening of the valve seat 21. A spring 1 22 is connected between the bottom of the stopper disc 18 and the top of the spacer 14.

[0039] Under normal conditions, spring 1 (22) forces valve block 19 and valve block 2 (20) to rest within valve seat 21, achieving a seal. When the amount of hydrogen fluoride gas in collection pipe 4 increases, causing pressure to rise, the gas pushes open sealing valve 15 and enters chamber 8. This reduces the pressure in collection pipe 4, and spring 1 (22) forces sealing valve 15 to descend, re-establishing the seal. This structural design ensures that hydrogen fluoride gas entering heat exchange chamber 9 is not continuous. When condensing hydrogen fluoride gas already in heat exchange chamber 9, it is not affected by the temperature of newly volatilized hydrogen fluoride gas, thus achieving rapid condensation.

[0040] Furthermore, a heat shield 6 is provided outside the collecting pipe 4, and the cooling pipe 7 is located inside the heat shield 6. The cooling pipe 7 reduces heat exchange with the external environment. A partition 32 is provided in the middle of the cooling pipe 7, which divides the cooling pipe 7 into cooling section 1 31 and cooling section 2 33. A water inlet ring 1 34, a water outlet ring 1 37, a water inlet ring 2 38, and a water outlet ring 2 41 are provided inside the cooling pipe 7. The water inlet ring 1 34 is connected to the cooling water inlet 16, and the water outlet ring 1 37 is connected to the cooling water outlet 17. A connecting pipe 1 35 is connected between the water inlet ring 1 34 and the upper portion of each cooling section 1 31. A telescopic pipe 1 36 is connected between the water outlet ring 1 37 and the lower portion of each cooling section 1 31. A telescopic pipe 2 39 is connected between the water inlet ring 2 38 and the upper portion of each cooling section 2 33. A connecting pipe 2 40 is connected between the water outlet ring 2 41 and the lower portion of each cooling section 2 33.

[0041] like Figure 4 、 Figure 6As shown, an extension tube 48 is connected to the side of water inlet ring 1 34, and an extension tube 49 is connected to the side of water inlet ring 2 38. An insertion tube 50 is connected to the upper portion of extension tube 2 49. A guide seat 51 is provided within extension tube 1 48, and the upper end of insertion tube 50 extends into guide seat 51. A sealing valve 52 is provided on the upper portion of guide seat 51. A spring 3 53 is connected between sealing valve 52 and guide seat 51. A connecting hole 54 is formed on the outer periphery of the portion of insertion tube 50 located within guide seat 51, and the outer periphery of insertion tube 50 is positioned against the inner wall of guide seat 51. Under the action of spring 3 53, sealing valve 52 is pressed against the upper portion of guide seat 51 to achieve a seal, thereby isolating insertion tube 50 from extension tube 1 48. When the water inlet ring 2 38 moves upward, it drives the insertion tube 50 to move upward, so that the upper end of the insertion tube 50 pushes open the sealing valve 2 52, thereby making the insertion tube 50 and the extension tube 1 48 connected through the connecting hole 1 54, that is, making the water inlet ring 1 34 and the water inlet ring 2 38 connected.

[0042] like Figure 4 、 Figure 7 As shown, the lower portion of the water outlet ring 1 37 is connected to a connecting pipe 1 55, and the upper portion of the water outlet ring 2 41 is connected to a connecting pipe 2 57. The lower end of the connecting pipe 1 55 is inserted into the upper end of the connecting pipe 2 57. A sealing plate 56 is connected to the lower portion of the connecting pipe 1 55. A connecting hole 2 58 is defined around the outer periphery of the portion of the connecting pipe 1 55 that inserts into the connecting pipe 2 57. A groove 60 is defined within the interior of the connecting pipe 2 57 below the sealing plate 56. Several sealing rings 59 are positioned around the outer periphery of the connecting pipe 1 55, located above the connecting holes 2 58 and within the connecting pipe 2 57. Under normal conditions, the outer periphery of the connecting pipe 1 55 abuts against the inner wall of the connecting pipe 2 57, achieving a seal. When the water outlet ring 37 moves downward, the lower end of the connecting pipe 1 55 moves downward in the connecting pipe 2 57, so that the connecting hole 2 58 on the connecting pipe 1 55 reaches the groove 60 in the connecting pipe 2 57, thereby making the connecting pipe 1 55 and the connecting pipe 2 57 connected through the connecting hole 2 58, that is, making the water outlet ring 2 41 and the water outlet ring 1 37 connected.

[0043] A driving mechanism is provided between the water inlet ring 2 38 and the water outlet ring 1 37, which can drive the water inlet ring 2 38 and the water outlet ring 1 37 to move relatively away from or closer to each other, thereby controlling the connectivity between the water inlet ring 1 34 and the water inlet ring 2 38, and between the water outlet ring 1 37 and the water outlet ring 2 41.

[0044] When the amount of hydrogen fluoride gas in collection pipe 4 is low, the connections between water inlet ring 1 34 and water inlet ring 2 38, and between water outlet ring 1 37 and water outlet ring 2 41 can be disconnected. Cooling water enters cooling section 1 31 only through water inlet ring 1 34 and then flows out through water outlet ring 1 37. This small amount of cooling water entering can meet the condensation demand. When the amount of hydrogen fluoride gas in collection pipe 4 increases, it can push valve block 1 19 out of valve seat 21. While valve block 20 is still in valve seat 21, the connections between water inlet ring 1 34 and water inlet ring 2 38, and between water outlet ring 1 37 and water outlet ring 2 41 are controlled, allowing cooling water to enter cooling section 1 31 and cooling section 2 33 to cool the interior of collection pipe 4. The amount of cooling water entering increases, thereby meeting the correspondingly increased condensation demand.

[0045] like Figure 4 、 Figure 5 As shown, the drive mechanism specifically includes a drive shaft 44 that is rotatably disposed within the heat shield 6. A drive gear 45 is connected to the drive shaft 44. Rack 1 42 and rack 2 43 are disposed on either side of the drive gear 45. Rack 1 42 and rack 2 43 are connected to water inlet ring 2 38 and water outlet ring 1 37, respectively. When the drive shaft 44 drives the drive gear 45 to rotate, the drive gear 45 drives rack 1 42 upward and rack 2 43 downward, thereby controlling the rise of water inlet ring 2 38 and the descent of water outlet ring 1 37.

[0046] The drive mechanism can also be linked to the raising and lowering of sealing valve 15. When hydrogen fluoride gas increases within collection pipe 4, it controls the movement of water inlet ring 2 38 and water outlet ring 1 37 to increase the amount of cooling water entering. Specifically, a guide tube 27 is connected to the side of the limit plate 18. A guide wheel 1 26 is located inside the collection pipe 4. The guide tube 27 is connected between the heat shield 6 and the collection pipe 4. A mounting bracket 28 is located at the corner of the guide tube 27. A guide wheel 29 is rotatably mounted on the mounting bracket 28. A connecting rope 30 passes around guide wheels 1 26 and 29 before being wound around a drive shaft 44. A torsion spring is sleeved around the drive shaft 44. One end of the torsion spring is connected to a drive gear 45, and the other end is connected to the inner wall of the heat shield 6. A limit block 46 is also connected to the side of the drive shaft 44, and a stop block 47 is located inside the heat shield 6. Under the action of the torsion spring, the limit block 46 presses against the stop block 47, thereby limiting the position of the drive shaft 44. At this time, the driving gear 45 is stationary, so that the positions of the second water inlet ring 38 and the first water outlet ring 37 are relatively fixed.

[0047] The collection pipe 4 is equipped with a mounting block 23, beneath which is a second spring 25. As the hydrogen fluoride gas in the collection pipe 4 increases and its pressure rises, it overcomes the force of spring 1 22, forcing the sealing valve 15 upward. The upper end of the stop plate 18 of the sealing valve 15 abuts against spring 25, preventing further upward movement of the sealing valve 15. As the sealing valve 15 rises, it pulls on the guide tube 27, which in turn acts on the drive shaft 44, causing the drive shaft 44 to rotate the drive gear 45, thereby driving racks 1 42 and 2 43, which in turn drive the movement of the second water inlet ring 38 and the first water outlet ring 37.

[0048] Until the hydrogen fluoride gas in the collection pipe 4 increases again, overcoming the elastic force of the second spring 25, causing the valve block 19 and valve block 20 of the sealing valve 15 to separate from the valve seat 21, and some of the hydrogen fluoride gas in the collection pipe 4 enters the chamber 8 through the valve seat 21 for condensation. A trigger can also be provided between the mounting block 23 and the limit plate 18. When the valve block 20 separates from the valve seat 21, the trigger between the mounting block 23 and the limit plate 18 is triggered, allowing the refrigerant to enter the condensing pipe 10 from the input pipe 11, thereby condensing the hydrogen fluoride gas entering the heat exchange chamber 9.

[0049] A guide rod 24 is connected to the lower portion of the mounting block 23 . The guide rod 24 is arranged to penetrate the limit plate 18 . The guide rod 24 guides the lifting and lowering of the limit plate 18 to prevent the limit plate 18 from deflecting.

[0050] Depending on the amount of volatilized hydrogen fluoride gas, the condensation method is different, thereby saving costs and reducing energy waste.

[0051] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for producing perfluorotripropylamine, characterized in that: The following steps are involved: S1, adding hydrogen fluoride solution to tripropylamine solution and mixing the two to form an electrolyte; S2, the air in the electrolytic cell is replaced by an inert gas, and after the replacement is completed, the mixed liquid is passed into the electrolytic cell; S3, low voltage direct current is introduced to carry out electrolytic fluorination reaction; the reaction pressure is normal pressure; S4, after the electrolysis is completed, tripropylamine is electrofluorinated to convert it into perfluorotripropylamine.

2. The method for producing perfluorotripropylamine according to claim 1, wherein: The molar ratio of tripropylamine to hydrogen fluoride is 1:48 to 1:

77.

3. The method for producing perfluorotripropylamine according to claim 1, wherein: The temperature is maintained at 10°C to 50°C during the electrolysis process.

4. The method for producing perfluorotripropylamine according to claim 1, wherein: The inert gas is nitrogen.

5. The method for producing perfluorotripropylamine according to claim 1, wherein: The voltage of the electrolysis reaction is 3V to 10V, and the current density is 5mA / cm 2 Up to 50mA / cm 2 .

6. The method for producing perfluorotripropylamine according to claim 1, wherein: The perfluorotripropylamine obtained in step S4 is separated to improve its purity.

7. The method for producing perfluorotripropylamine according to claim 1, wherein: The volatilized hydrogen fluoride is condensed by a condensation mechanism, and the condensed hydrogen fluoride liquid is reintroduced into the electrolytic cell.

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