A synthesis method and application of perfluorotripropylamine

Abstract

The present application proposes a synthesis method and application of perfluorotripropylamine, wherein the synthesis method of perfluorotripropylamine comprises: reacting dipropylamine and hexafluoropropylene in a first reaction to obtain a mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine; and reacting the mixture with hydrogen fluoride in a second reaction to obtain perfluorotripropylamine. The synthesis method of perfluorotripropylamine of the present application uses hexafluoropropylene and dipropylamine as raw materials, which are reacted together with hydrogen fluoride to synthesize perfluorotripropylamine in high yield, while reducing energy consumption in the production process and greenhouse gas emissions in the tail gas, thereby improving atom economy.

Description

Technical Field

[0001] The present application relates to the technical field of organic compound synthesis, and in particular to a synthesis method and application of perfluorotripropylamine. Background Art

[0002] Perfluorotripropylamine (also known as perfluoroamine), whose largest manufacturer and distributor is 3M in the United States, is marketed under the trade name FC-3283. This colorless, odorless, non-toxic, and non-flammable inert liquid exhibits excellent compatibility with most materials. It is primarily used as an anti-corrosion transmission fluid for instrumentation, a dielectric insulating fluid, and a leak detector for electronic components and devices. Its excellent gas solubility and biological inertness make it a suitable raw material for the production of blood substitutes.

[0003] There are two methods for synthesizing perfluorotripropylamine. CN103145561A describes a process for synthesizing perfluorotripropylamine by reacting fluorine-nitrogen gas with vaporized tripropylamine at about 300°C in a tubular fluorination reactor filled with cobalt oxide. This process not only requires the handling of highly toxic and dangerous fluorine gas, but also has a low reaction efficiency (it must be diluted with a large amount of inert gas), and the collection of products caused by gas entrainment is also relatively difficult, making it unsuitable for industrial large-scale production. Another synthesis method is described in US2616927 and EP0528192A, which uses tri-n-propylamine and HF as raw materials to synthesize perfluorotripropylamine through electrochemical fluorination in a dedicated electrolyzer. This method is also the most mature commercial synthesis method to date. However, as can be seen from literature reports and detection during actual production, the products after electrolytic fluorination are very numerous, and the types of gases such as fluorinated alkanes (all greenhouse gases) that are difficult to collect in the tail gas are also very numerous.

[0004]

[0005] Table 1 lists the GWP values ​​of some fluorinated alkanes (from the IPCC Fifth Assessment Report).

[0006] Table 1 GWP values ​​of some fluorinated alkanes

[0007]

[0008]

[0009] At the same time, based on literature reports and calculations of the actual production process, the raw materials, power consumption, and production amounts of each component of electrolytic tri-n-propylamine fluoride are shown in Table 2.

[0010] Table 2 Consumption generation table of electrolytic fluorination synthesis of perfluorotripropylamine

[0011]

[0012] *Note: This is the effective yield of perfluorotripropylamine. After distillation and purification, the perfluorotripropylamine (FC-3283) sold as a commodity is almost 1kg, that is, 1kg of tripropylamine is consumed to produce 1kg of commercial-grade perfluorotripropylamine. The product yield is 27% (the highest value in the literature and actual production process).

[0013] As can be seen from Table 2, the process of synthesizing perfluorotripropylamine from tri-n-propylamine electrolytic fluorination is a process with high energy consumption (55-62 degrees / kg product) and high greenhouse gas production (2.1 kg / kg product).

[0014] Therefore, how to develop a production process for perfluorotripropylamine that has low energy consumption and can effectively reduce greenhouse gas emissions during the production process is a difficult problem in this field. Summary of the Invention

[0015] In view of this, an object of the present application is to provide a method for synthesizing perfluorotripropylamine, which uses hexafluoropropylene and dipropylamine as raw materials and reacts with hydrogen fluoride to synthesize perfluorotripropylamine in high yield, while reducing energy consumption in the production process and greenhouse gas emissions in the exhaust gas, thereby improving atom economy.

[0016] Another object of the present application is to provide an application of perfluorotripropylamine synthesized by a method for synthesizing perfluorotripropylamine.

[0017] To achieve the above objectives, the first aspect of the present application provides a method for synthesizing perfluorotripropylamine, comprising:

[0018] performing a first reaction of dipropylamine and hexafluoropropylene to obtain a mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine;

[0019] The mixture is subjected to a second reaction with hydrogen fluoride to obtain perfluorotripropylamine.

[0020] In some embodiments, the reaction temperature of the first reaction is 0-25°C.

[0021] In some embodiments, in the first reaction, the molar ratio of the dipropylamine to the hexafluoropropylene is 1:(1.07-1.2).

[0022] In some embodiments, in the first reaction, the water content of the dipropylamine is less than 30 ppm, preferably less than 10 ppm.

[0023] In some embodiments, the hexafluoropropylene has a moisture content of less than 10 ppm.

[0024] In some embodiments, the first reaction comprises a first stage and a second stage performed sequentially; the reaction temperature of the first stage of the first reaction is 0-10°C.

[0025] In some embodiments, the initial reaction pressure of the first stage of the first reaction is 30-50 KPa.

[0026] In some embodiments, the termination reaction pressure of the first stage of the first reaction is 300-500 KPa.

[0027] In some embodiments, the reaction temperature of the second stage of the first reaction is 15-25°C.

[0028] In some embodiments, the reaction pressure of the second stage is 300-500 KPa.

[0029] In some embodiments, the reaction time of the second stage is 1.5-2.5 hours.

[0030] In some embodiments, when the reaction pressure of the first stage reaches the first stage termination reaction pressure and the drop value of the first stage termination reaction pressure within the target time is lower than a preset value, the first reaction enters the second stage from the first stage.

[0031] In some embodiments, the target time is 8-12 minutes.

[0032] In some embodiments, the preset value is 8-12% of the first stage termination reaction pressure.

[0033] In some embodiments, the dipropylamine is added to the reaction system of the first reaction before the first stage.

[0034] In some embodiments, the hexafluoropropylene is added to the reaction system of the first reaction in two parts, one part is continuously added to the reaction system of the first reaction in the first stage, and the other part is added to the reaction system of the first reaction in the second stage.

[0035] In some embodiments, the second reaction is an electrochemical fluorination reaction.

[0036] In some embodiments, the second reaction is performed in a Simons electrolyzer.

[0037] In some embodiments, in the second reaction, the mass ratio of the mixture obtained in the first reaction to the hydrogen fluoride is 1:(5.83-6.00).

[0038] In some embodiments, the electrolysis voltage of the second reaction is 5-7.5V.

[0039] In some embodiments, the current density of the second reaction is 0.01-0.03 A / cm 2 .

[0040] In some embodiments, the temperature of the second reaction is 15-19°C, preferably 15-17°C.

[0041] The second aspect of the present application relates to the application of perfluorotripropylamine synthesized by the synthesis method of perfluorotripropylamine described in the present application in the fields of instrumentation, biomedicine, etc.

[0042] The synthesis method of perfluorotripropylamine described in this application can at least bring the following beneficial effects:

[0043] By synthesizing a mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine—an intermediate product from hexafluoropropylene and dipropylamine—and then reacting this mixture with hydrogen fluoride as a raw material, perfluorotripropylamine can be synthesized with high yield while reducing energy consumption and greenhouse gas emissions in the production process, thereby improving atom economy. Specifically, the product yield has increased from 25-30% in the original process to over 60%, energy consumption has been reduced by over 30%, and total greenhouse gas emissions have been reduced by over 70%.

[0044] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings.

[0046] in:

[0047] Figure 1 This is a gas chromatography-mass spectrometry (GC-MS) test spectrum of the product synthesized by the synthesis method of perfluorotripropylamine in Example 1.

[0048] Figure 2 This is the NMR fluorine spectrum of perfluoromethyldipropylamine in the product synthesized by the synthesis method of perfluorotripropylamine in Example 1.

[0049] Figure 3 This is the NMR fluorine spectrum of perfluoroethyldipropylamine in the product synthesized by the synthesis method of perfluorotripropylamine in Example 1.

[0050] Figure 4 This is the NMR fluorine spectrum of fluoromethylperfluorodipropylamine in the product synthesized by the synthesis method of perfluorotripropylamine in Example 1.

[0051] Figure 5 This is the NMR fluorine spectrum of perfluorotripropylamine, the target product of the synthesis method of perfluorotripropylamine in Example 1. DETAILED DESCRIPTION

[0052] The embodiments of the present application are described in detail below. The embodiments are exemplary and intended to be used to explain the present application, but should not be understood as limiting the present application.

[0053] Throughout this application, the disclosure of numerical ranges includes disclosure of all values ​​within the entire range and further subdivided ranges, including the endpoints and subranges given within those ranges.

[0054] In this application, the raw materials, equipment, etc. involved, unless otherwise specified, are all raw materials and equipment that can be obtained through commercial channels or known methods; the methods involved, unless otherwise specified, are all conventional methods.

[0055] In this application, the reaction pressures involved are all absolute pressures.

[0056] In this application, greenhouse gases include carbon dioxide, perfluoromethane, perfluoroethane, perfluoropropane, nitrogen trifluoride, etc.

[0057] The inventors discovered that by using hexafluoropropylene and dipropylamine as the synthetic intermediate raw materials, perfluorotripropylamine can be synthesized in high yield through reactions such as electrolytic fluorination, while reducing energy consumption in the production process and greenhouse gas emissions in the tail gas, with significant atom economy.

[0058] The synthesis method of perfluorotripropylamine in the embodiment of the present application comprises the following steps:

[0059] S101. Perform a first reaction on dipropylamine and hexafluoropropylene to obtain a mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine.

[0060] In the embodiments of the present application, the reaction equation for the first reaction of dipropylamine and hexafluoropropylene to obtain a mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine is as follows:

[0061]

[0062] Among them, Formula 1 is dipropylamine, Formula 2 is hexafluoropropylene, Formula 3 is 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine, and Formula 4 is 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine.

[0063] In some embodiments, the molar ratio of dipropylamine to hexafluoropropylene is 1:(1.07-1.2), including but not limited to 1:1.07, 1:1.08, 1:1.09, 1:1, 1:1.12, 1:1.15, 1:1.18 or 1:1.2, etc.

[0064] In some embodiments, the water content of the dipropylamine is less than 30 ppm, including but not limited to less than 25 ppm, less than 20 ppm, less than 15 ppm, less than 10 ppm, or less than 5 ppm.

[0065] As a preferred example, the water content of dipropylamine is less than 10 ppm, including but not limited to 9 ppm, 7.5 ppm, 5 ppm, 2.5 ppm, 1 ppm or 0.

[0066] In some embodiments, the water content of hexafluoropropylene is less than 10 ppm, including but not limited to 9 ppm, 7.5 ppm, 5 ppm, 2.5 ppm, 1 ppm or 0, etc.

[0067] In the examples of the present application, the water content of dipropylamine is controlled to be less than 30 ppm, and the water content of hexafluoropropylene is controlled to be less than 10 ppm.

[0068] In some embodiments, the reaction temperature of the first reaction is 0-25°C, including but not limited to 0°C, 1°C, 2°C, 3°C, 4°C, 5°C, 6°C, 7°C, 8°C, 9°C, 10°C, 12.5°C, 15°C, 17.5°C, 20°C, 22.5°C or 25°C, etc., preferably 0-10°C, more preferably 0-5°C.

[0069] It should be noted that, in the embodiments of the present application, dipropylamine and hexafluoropropylene can be added to the reaction system of the first reaction at one time for reaction, or dipropylamine and hexafluoropropylene can be added to the reaction system of the first reaction in batches.

[0070] As an optional example, when dipropylamine and hexafluoropropylene are added to the reaction system of the first reaction at one time, the reaction temperature is controlled at 0-10° C. as much as possible, and the reaction pressure of the first reaction is controlled at 300-500 KPa (absolute pressure).

[0071] As another optional example, the first reaction includes a first stage and a second stage that are performed sequentially.

[0072] In some embodiments, dipropylamine is added to the reaction system of the first reaction before the first stage.

[0073] In some embodiments, hexafluoropropylene is added to the reaction system of the first reaction in two parts, one part is continuously added to the reaction system of the first reaction in the first stage, and the other part is added to the reaction system of the first reaction in the second stage.

[0074] In the embodiments of the present application, the purpose of adding hexafluoropropylene in the first stage is to make the pressure in the first reaction system reach the termination reaction pressure of the first stage. Therefore, there is no limitation on the amount of hexafluoropropylene added in the first stage, as long as the pressure in the reaction system can reach the termination reaction pressure of the first stage after its addition.

[0075] In some embodiments, the reaction temperature of the first stage is 0-10°C, including but not limited to 0°C, 1°C, 2°C, 3°C, 4°C, 5°C, 6°C, 7°C, 8°C, 9°C or 10°C, etc., preferably 0-5°C.

[0076] In some embodiments, the initial reaction pressure of the first stage is below 50 KPa, including but not limited to 20 KPa, 25 KPa, 30 KPa, 35 KPa, 40 KPa, 45 KPa or 50 KPa.

[0077] As an optional example, the initial reaction pressure of the first stage is 30-50 KPa.

[0078] In some embodiments, the termination reaction pressure of the first stage is 300-500 KPa, including but not limited to 300 KPa, 350 KPa, 400 KPa, 450 KPa or 500 KPa, etc., preferably 500 KPa.

[0079] In some embodiments, when the reaction pressure of the first stage reaches the above-mentioned termination reaction pressure of 300-500 kPa, and the termination reaction pressure drop value of the first stage within the target time is lower than the preset value, the first reaction enters the second stage from the first stage.

[0080] Exemplarily, the target time is 8-12 minutes, including but not limited to 8 minutes, 9 minutes, 10 minutes, 11 minutes or 12 minutes, preferably 10 minutes.

[0081] Exemplarily, the preset value is 8-12% of the termination reaction pressure of the first stage, including but not limited to 8%, 9%, 10%, 11% or 12% of the termination reaction pressure of the first stage, preferably 10%.

[0082] In some embodiments, the reaction temperature of the second stage is 15-25°C, including but not limited to 15°C, 17.5°C, 20°C, 22.5°C or 25°C.

[0083] In some embodiments, the reaction pressure in the second stage is 300-500 KPa, including but not limited to 300 KPa, 350 KPa, 400 KPa, 450 KPa or 500 KPa.

[0084] In some embodiments, the reaction time of the second stage is 1.5-2.5 h, including but not limited to 1.5 h, 1.8 h, 2 h, 2.2 h or 2.5 h.

[0085] In some embodiments, the method for synthesizing perfluorotripropylamine further comprises the step of replacing the gas phase space in the reaction system of the first reaction and hydrogen fluoride and hexafluoropropylene in the reaction solution with an inert gas after the first reaction.

[0086] Illustratively, the inert gas includes but is not limited to at least one of nitrogen, argon, helium, and the like.

[0087] S102, subjecting the mixture obtained in step S1 to a second reaction with hydrogen fluoride to obtain perfluorotripropylamine.

[0088] In the embodiment of the present application, the reaction equation for the second reaction of the mixture obtained in step S1 with hydrogen fluoride is as follows:

[0089]

[0090] Wherein, Formula 3 is 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine, Formula 4 is 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine, and Formula 5 is perfluorotripropylamine.

[0091] It should be noted that the second reaction in the embodiment of the present application is an electrochemical fluorination reaction.

[0092] In some embodiments, the second reaction is performed in a Simons electrolyzer.

[0093] In some embodiments, the current density of the second reaction is 0.01-0.03 A / cm 2 , including but not limited to 0.01A / cm 2 , 0.015A / cm 2 , 0.02A / cm 2 , 0.025A / cm 2 or 0.03A / cm 2 wait.

[0094] In some embodiments, the electrolysis voltage of the second reaction is 5-7.5 V, including but not limited to 5 V, 5.5 V, 6 V, 6.5 V, 7 V or 7.5 V, etc.

[0095] In some embodiments, the temperature of the second reaction is 15-19°C, including but not limited to 15°C, 16°C, 17°C, 18°C, or 19°C.

[0096] As a preferred example, the temperature of the second reaction is 15-17°C.

[0097] In some embodiments, when the electrolysis voltage of the second reaction is greater than 7.5 V and the current density of the second reaction is less than 0.01 A / cm 2 The second reaction stops.

[0098] In some embodiments, the molar ratio of the mixture obtained in step S1 to hydrogen fluoride is 1:(5.83-6.00), including but not limited to 1:5.83, 1:5.87, 1:5.9, 1:5.95 or 1:6.

[0099] In some embodiments, the hydrogen fluoride is anhydrous hydrogen fluoride (water content ≤ 10 ppm).

[0100] Exemplarily, the water content of hydrogen fluoride is less than 10 ppm, including but not limited to 9 ppm, 8 ppm, 7 ppm, 6 ppm or 5 ppm.

[0101] The synthesis method of perfluorotripropylamine in the embodiments of the present application uses hexafluoropropylene and dipropylamine to synthesize an intermediate product—a mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine. This mixture is then reacted with hydrogen fluoride as a raw material. This method can synthesize perfluorotripropylamine in high yield while reducing energy consumption during the production process and greenhouse gas emissions in the tail gas, thereby improving atom economy. Specifically, the product yield is increased from 25-30% in the original process to over 60%, energy consumption is reduced by over 30%, and total greenhouse gas emissions are reduced by over 70%.

[0102] The perfluorotripropylamine synthesized by the method for synthesizing perfluorotripropylamine in the embodiment of the present application can be widely used in fields such as instrumentation and biomedicine.

[0103] For example, the perfluorotripropylamine synthesized by the method for synthesizing perfluorotripropylamine in the embodiment of the present application can be used in corrosion-resistant transmission fluids for instruments and meters, dielectric insulating fluids, and leak detection fluids for electronic components and devices.

[0104] For example, the perfluorotripropylamine synthesized by the method for synthesizing perfluorotripropylamine according to the embodiment of the present application can be used as a raw material for the production of blood substitutes.

[0105] Certain features of the present technology are further illustrated in the following non-limiting examples.

[0106] Example 1

[0107] The synthesis method of perfluorotripropylamine of the present embodiment comprises the following steps:

[0108] (1) A mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine was prepared.

[0109] The reaction was carried out in a 5L stainless steel reactor with a stirring mechanism. The reactor was jacketed and cooled with silicone oil at -15°C for temperature control. 1010g (10 mol) of dipropylamine (previously dehydrated and having a moisture content of ≤30ppm) was added to the reactor. The dipropylamine in the reactor was cooled to 0°C±1°C by passing refrigerant silicone oil into the jacket while stirring (300 rpm). The reactor was evacuated to below 50 kPa (absolute pressure). Hexafluoropropylene (with a moisture content of ≤10ppm) was then introduced into the reactor. The reaction temperature was controlled between 0 and 5°C. The reaction was allowed to proceed until the pressure in the reactor reached 500 kPa and the pressure drop within 10 minutes did not exceed 10%. The reaction entered its final stage. The temperature in the reactor was raised to 20°C, and 1605g (10.7 mol) of hexafluoropropylene was added. The pressure in the reactor was maintained at 500 kPa and the reaction was continued for 2 hours to terminate the reaction. After the reaction, the reactor vent valve was opened and the gas phase space within the reactor was replaced with nitrogen. The temperature was then continued to rise to 40°C to completely displace the HF and hexafluoropropylene in the reaction solution. 2400g of crude product was ultimately obtained. During reduced pressure distillation, the fraction at 57-65°C was collected under a vacuum of 16-17 mmHg, yielding 2366g of a colorless, transparent product. Gas chromatography (GC) analysis revealed that the colorless, transparent product was a mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine, with a mass ratio of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine to 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine of 1.2:1.

[0110] (2) Synthesis of perfluorotripropylamine.

[0111] The colorless transparent product obtained in step (1) was directly added into a Simons electrolytic cell (15 L, plate area 50 dm 2), the effective mass of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine in the colorless transparent product obtained in step (1) is calculated as 2400g, and the mass ratio of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine to 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine is 1.2:1. 14kg of anhydrous HF (water content less than 10ppm) is added to the electrolytic cell. The electrolytic cell is powered on to start the electrochemical fluorination reaction. When the electrolytic cell voltage reaches 5V or above, the power consumption is calculated using an ammeter. The electrolysis is stopped when the electrolysis voltage exceeds 7.5V and the current is less than 30A. During the electrolysis process, the temperature in the electrolytic cell was controlled at 15-17°C and the current was 30-150A. Anhydrous HF was added in a timely manner, and the amount of anhydrous HF added was recorded. The total amount of tail gas (after absorption by alkali solution) was calculated by a mass flow meter, and the tail gas composition was continuously sampled and analyzed (GC, refer to GB7445-87).

[0112] After the electrolysis was completed, the organic fluorine compounds at the bottom of the electrolytic cell were collected and 4644 g of crude product was obtained after alkali washing. The GC-MS analysis showed the following spectrum: Figure 1 As shown in Table 3, the main component results after each component was determined are shown in Table 3.

[0113] Table 3 Detection and analysis results of each component of the crude product of Example 1

[0114] Peak time (min) content(%) Mass spectrometry analysis results 7.333 2.261 Perfluoromethyldipropylamine 8.131 65.518 Perfluorotripropylamine 8.562 5.210 Perfluoro-N-propyl-2-ethyltetrafluoropyrrole 8.769 11.335 Perfluoro-N-propyl-2-ethyltetrafluoropyrrole 9.235 2.091 Perfluoro-N-propyl-2-ethyltetrafluoropyrrole 9.604 2.321 Monohydroperfluoro-N-propyl-2-ethyltetrafluoropyrrole 9.770 6.094 Perfluorotripropylamine with three unsubstituted hydrogen atoms 10.213 4.609 Perfluorotripropylamine with three unsubstituted hydrogen atoms

[0115] Combine Figure 1 As shown in Table 3, the peak times of 8.562, 8.769, and 9.235 are speculated to be three isomers (chiral isomers) of each other, while the peak times of 9.770 and 10.213 are speculated to be two isomers of each other.

[0116] After chromatographic separation, the components of the crude product of Example 1 were subjected to nuclear magnetic resonance fluorine spectrum and other tests, and the results of the main components are shown in Table 4.

[0117] Table 4 Qualitative analysis results of each component in the crude product of Example 1

[0118]

[0119]

[0120] After HF was recovered from the electrolyte, the cumulative HF consumption was calculated to be approximately 4.5 kg (electrochemical reaction consumption + organic phase entrainment + exhaust gas entrainment). The electrolytic cell consumed a total of 59.8 kWh of electricity. Through distillation, a total of 2786 g of product meeting FC3283 quality standards was obtained.

[0121] After cumulative calculation, the total amount of tail gas (after potassium hydroxide alkaline washing) generated during the electrolysis process is 866 g. The content of each component is shown in Table 5 through GC-MS analysis.

[0122] Table 5 Analysis of the content of each component in the tail gas of Example 1

[0123] Peak time (min) content(%) Parsing results 1.157 33.219 hydrogen 4.172 2.261 Perfluoromethane 4.453 5.130 Monohydroperfluoromethane 8.195 35.123 Perfluoroethane 10.443 22.12 Perfluoropropane

[0124] It can be seen from Table 5 that the main components of the tail gas during the electrolysis process of this embodiment are hydrogen, perfluoroethane and perfluoropropane.

[0125] Finally, a table of raw materials, energy consumption and three wastes generated was obtained through statistical calculation, which was compared with the conventional synthesis of perfluorotripropylamine using tri-n-propylamine as raw material (Table 2), as shown in Table 6.

[0126] Table 6 Comparison of the process indicators of Example 1 with those of conventional electrolytic fluorination

[0127]

[0128] As can be seen from Table 6, when the mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine is used as the raw material for electrolytic fluorination, the HF consumption is reduced by 63.13%, and the yield based on the raw material is increased from 27% (conventional electrolytic fluorination) to 55.89%. The power consumption is reduced by nearly 2 / 3, and the production of fluorinated low-boiling alkanes (greenhouse gases) is reduced by nearly 90%.

[0129] Example 2

[0130] The synthesis method of perfluorotripropylamine of the present embodiment comprises the following steps:

[0131] (1) A mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine was prepared.

[0132] The reaction was conducted in a 200L stainless steel reactor with a stirring mechanism and jacket. -15°C cooling silicone oil was introduced to control the reaction temperature. 50kg of pre-dehydrated dipropylamine (10ppm) was added to the reactor. While stirring (300 rpm), the reactor was cooled to 0°C ± 1°C by introducing refrigerant silicone oil. The reactor was then evacuated to below 50kPa (absolute pressure). Hexafluoropropylene (30ppm) was introduced into the reactor and the reaction was carried out at 2.5°C. The reaction reached its final stage when the pressure in the reactor reached 500kPa and the pressure drop within 10 minutes did not exceed 10%. At this point, the reactor temperature was raised to 20°C and 80kg of hexafluoropropylene was introduced. The reactor pressure was maintained at 500kPa for 2 hours, and the reaction was completed.

[0133] (2) Prepare the electrolyte.

[0134] Add 500 kg of anhydrous HF (water content 20 ppm) to a 1000 L stainless steel reactor. Cool the mixture to 0°C via the jacket while stirring. Slowly add the previously synthesized raw materials (approximately 124.2 kg) to the reactor using a metering pump at a rate of ≤ 20 kg / h, while controlling the temperature of the ingredients to not exceed 15°C. After the raw materials are added, continue stirring for 1 hour. Once the mixture is complete, cool the reaction solution to 10-15°C.

[0135] (2) Synthesis of perfluorotripropylamine.

[0136] Add 100 L of the electrolyte prepared in step (2) to a Simons electrolytic cell with an effective volume of 120 L, apply a voltage of 5 to 7.5 V to both ends of the electrodes, control the temperature in the electrolytic cell to 15 to 19 ° C, and the current density to 0.01 to 0.03 A / cm 2 (The current during electrolysis is about 150A to 500A). During the electrolysis process, add an appropriate amount of electrolyte (calculate the raw material consumption based on the power consumed by electrolysis) and an appropriate amount of HF every 24 hours. At the same time, discharge the fluorinated organic compounds at the bottom of the electrolytic cell. Continue electrolysis (only add HF) until the prepared electrolyte is consumed, until the electrolytic cell voltage exceeds 7.5V and the current density is less than 0.01 / cm 2 Stop electrolysis at 1:00, calculate the total amount of fluorinated organic compounds, recover HF, cumulatively calculate tail gas emissions (analyze the average component content), calculate the high-boiling point residual liquid (including the total amount of the bottom liquid after distillation and the bottom liquid after distillation to recover HF), and record the total power consumption. Summary statistics table 7.

[0137] Table 7 Comparison of the process indicators of Example 2 with those of conventional electrolytic fluorination

[0138]

[0139] Examples 3-5 are basically the same as Example 2, except that some process control indicators are different, as shown in Table 8.

[0140] Table 8 Process control indicators of the synthesis process in Examples 3-5

[0141]

[0142]

[0143] After statistics, the comparison of the consumption of each indicator in Examples 1-5 and the average consumption of the indicator when using tri-n-propylamine electrolysis is shown in Table 9.

[0144] Table 9 Index consumption comparison (compared with the average index consumption during electrolysis of tri-n-propylamine)

[0145] Example 1 Example 2 Example 3 Example 4 Example 5 Reduced HF consumption 63.32％ 59.30％ 59.23％ 58.66％ 55.34％ The yield increased from 27% to 55.89％ 51.80％ 54.13％ 55.06％ 54.56％ Reduced power consumption 65.32％ 59.35％ 57.90％ 56.29％ 56.45％ Reduced greenhouse gas production 90.10％ 89.52％ 89.86％ 89.57％ 89.24％

[0146] In this application, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0147] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0148] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for synthesizing perfluorotripropylamine, characterized in that: include: performing a first reaction of dipropylamine and hexafluoropropylene to obtain a mixture of 1,1,2,3,3,3-hexafluoro-N,N-dipropylamine and 1,2,3,3,3-pentafluoro-N,N-dipropyl-1-propenylamine; performing a second reaction of the mixture with hydrogen fluoride to obtain perfluorotripropylamine; The second reaction is an electrochemical fluorination reaction.

2. The synthesis method according to claim 1, wherein The reaction temperature of the first reaction is 0-25°C; and / or, In the first reaction, the molar ratio of dipropylamine to hexafluoropropylene is 1:(1.07-1.2).

3. The synthesis method according to claim 1, wherein In the second reaction, the mass ratio of the mixture to the hydrogen fluoride is 1:(5.83-6.00).

4. The synthesis method according to claim 1, characterized in that In the first reaction, the water content of dipropylamine is less than 30 ppm; and / or, In the first reaction, the water content of hexafluoropropylene is less than 10 ppm.

5. The synthesis method according to claim 4, characterized in that In the first reaction, the water content of the dipropylamine is less than 10 ppm.

6. The synthesis method according to claim 1, characterized in that The first reaction includes a first stage and a second stage carried out sequentially, the reaction temperature of the first stage is 0-10°C, and / or the initial reaction pressure of the first stage is 30-50 KPa, and / or the termination reaction pressure of the first stage is 300-500 KPa, and / or the reaction temperature of the second stage is 15-25°C, and / or the reaction pressure of the second stage is 300-500 KPa, and / or the reaction time of the second stage is 1.5-2.5 h.

7. The synthesis method according to claim 6, characterized in that When the reaction pressure of the first stage reaches the termination pressure of the first stage and the drop value of the termination pressure of the first stage within the target time is lower than the preset value, the first reaction enters the second stage from the first stage; and / or, The dipropylamine is added to the reaction system of the first reaction before the first stage; and / or, The hexafluoropropylene is added to the reaction system of the first reaction in two parts, one part is continuously added to the reaction system of the first reaction in the first stage, and the other part is added to the reaction system of the first reaction in the second stage.

8. The synthesis method according to claim 7, characterized in that The target time is 8-12 minutes; and / or, The preset value is 8-12% of the first stage termination reaction pressure.

9. The synthesis method according to claim 1, characterized in that The second reaction is carried out in a Simons electrolytic cell; and / or, the electrolysis voltage of the second reaction is 5-7.5V; and / or, The current density of the second reaction is 0.01-0.03A / cm 2 and / or, The temperature of the second reaction is 15-19°C.

10. The synthesis method according to claim 9, characterized in that The temperature of the second reaction is 15-17°C.

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