A continuous device for preparing fluorine-containing olefins and a method thereof

Abstract

The application discloses a continuous preparation device of fluorine-containing olefins, comprising a reactor, a fluorine-containing alkane supply device, a mixed alkali liquor supply device, a rectifying tower and a product storage tank, and discloses a method for continuously preparing fluorine-containing olefins by using the device. The application has the advantages of simple structure, high reaction efficiency, green environmental protection, safety and controllability.

Description

Technical Field

[0001] This invention relates to the field of fluorinated olefins technology, and more specifically, to a continuous preparation apparatus and method for fluorinated olefins. Background Technology

[0002] Alkenes with fluorinated groups can be used in the synthesis of various fluoropolymers and are widely used in fields such as architectural coatings, textile finishing, and optical communications. The synthesis of fluorinated alkenes mainly involves base-based elimination reactions. Currently, there are three main industrial production methods:

[0003] One method involves reacting fluoroalkyl halogenated ethanes with an aqueous solution of an inorganic base. To improve reaction efficiency, a phase transfer catalyst is added to the system, leading to an elimination reaction to obtain perfluoroalkyl ethylene. For example, CN105837397A discloses a method for synthesizing perfluoroalkyl ethylene, in which perfluoroalkyl ethyl iodide is mixed with an aqueous solution of an inorganic base, a phase transfer catalyst is added, and the mixture is stirred and heated to carry out an elimination reaction at 0–100°C. After the reaction, the reaction solution is cooled to room temperature and allowed to stand for phase separation. The lower organic phase is separated and washed to obtain the product, perfluoroalkyl ethylene. This method is simple to operate, has mild reaction conditions, and the product is easy to purify, avoiding the use of solvents. Furthermore, the phase transfer catalyst can be recycled, saving costs and being safe and environmentally friendly. However, because a phase transfer catalyst is introduced into the system, the washing and separation process is difficult, and corresponding organic waste liquid is generated, which is detrimental to the environment and production. In addition, substitution reactions easily occur in this reaction, yielding fluorinated alcohols, resulting in low yields and making it uneconomical.

[0004] The second method involves reacting fluorinated alkyl halogenated ethanes with an excess of inorganic base and an alcohol-water solvent to form an organic base solution. After heating and stirring under reflux for a period of time, perfluoroalkyl ethylene is obtained by vacuum distillation. In this method, the alcohol-water solvent and product can be separated by simple layer separation, and the solvent can be recovered by distillation. The drawback is that this method is a batch reaction, resulting in low production efficiency.

[0005] Thirdly, methods based on solid-liquid phase reactions, such as the preparation method of perfluoroalkylethylene disclosed in patent CN114105727A, involve mixing perfluoroalkyl ethyl iodine with powdered inorganic alkali, heating the reaction, and directly distilling the product to obtain perfluoroalkylethylene. The purity of the obtained perfluoroalkylethylene can reach 99%, and the yield can reach up to 96.7%. Another example is patent CN115093307A, which uses a slurry made by mixing perfluoroalkyl ethyl iodine with dehydrated solid alkali powder and continuously reacting it in a microwave-heated tubular reactor. The gaseous product is then separated by distillation to obtain perfluoroalkylethylene, with a maximum purity of 99.5% and a yield of 95.2%. Both of these methods suffer from problems such as unreacted raw materials mixing with solid waste, making separation and reuse difficult, difficulties in waste treatment, and low raw material utilization. Meanwhile, the core reactor used in the process described in CN115093307A is a microwave-heated tubular reactor. The product contains a mixture of raw materials and solid slag, which can easily clog pipelines, increase the frequency of equipment maintenance, and make it difficult to achieve continuous production. Summary of the Invention

[0006] To overcome the aforementioned problems in the prior art, the purpose of this invention is to provide a continuous preparation device and method for fluorinated olefins that is simple in structure, has high reaction efficiency, low cost, and is environmentally friendly.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a continuous preparation apparatus for fluorinated olefins, comprising a reactor, a fluorinated alkane supply device, a mixed alkali supply device, a distillation column, and a product storage tank. The reactor is a hypergravity reactor, comprising a shell. A first isolation member and a second isolation member are provided within the shell, dividing the interior of the shell from top to bottom into a material separation chamber, a reaction chamber, and a material mixing reaction chamber. Multiple reaction material conveying channels connecting the material separation chamber and the material mixing reaction chamber are provided on the first isolation member, the reaction chamber, and the second isolation member. A gas outlet is provided at the top of the material separation chamber, and a liquid overflow outlet is provided on the side of the material separation chamber. The gas outlet is connected to the distillation column, and the product outlet of the distillation column is connected to the product storage tank. A rotating packed bed is provided inside the material mixing reaction chamber, with a mixing chamber at the center of the rotating packed bed. A packing chamber for placing packing material is provided around the mixing chamber. The fluorinated alkane supply device is connected to the mixing chamber through a raw material feed pipe, and the mixed alkali supply device is connected to the mixing chamber through an alkali feed pipe.

[0008] In a preferred embodiment of the present invention, the preparation apparatus further includes a mixed alkali recovery device, wherein the liquid overflow port is connected to the mixed alkali recovery device.

[0009] In a preferred embodiment of the present invention, the mixed alkali recovery device is connected to the mixed alkali supply device.

[0010] In a preferred embodiment of the present invention, the raw material feed pipe and the alkali feed pipe are connected to the mixing chamber through the first isolation member and the second isolation member from the top of the shell.

[0011] In a preferred embodiment of the present invention, the reaction material conveying channels are uniformly distributed along the axial direction.

[0012] This invention also provides a method for the continuous preparation of fluorinated olefins using the above-described apparatus, comprising the following steps:

[0013] (1) Fluorinated alkanes are continuously fed into the supergravity reactor through the raw material feed pipe, and mixed alkaline solution is continuously fed into the supergravity reactor through the alkaline solution feed pipe. The reactants are fully mixed and reacted under the centrifugal action of the rotating packed bed.

[0014] (2) The reacted material is centrifuged by the rotating packed bed and enters the reaction chamber through the reactant conveying channel for further reaction;

[0015] (3) The gas-liquid mixture reaction product containing fluorinated olefins enters the material separation chamber through the reaction material conveying channel. The fluorinated olefins are separated from the gas outlet in gaseous form and enter the distillation tower. The remaining liquid material enters the mixed alkali recovery device through the liquid overflow port.

[0016] (4) The purified product after distillation enters the product storage tank through the product outlet of the distillation tower.

[0017] In a preferred embodiment of the present invention, the preparation apparatus further includes a mixed alkali solution recovery device, wherein unreacted mixed alkali solution enters the mixed alkali solution recovery device through the liquid overflow port.

[0018] In a preferred embodiment of the present invention, the mixed alkaline solution is a mixture of alkali and alcohol and / or water, wherein the mass percentage content of alkali in the mixture is 20-50%; the alkali is KOH or NaOH; and the alcohol is ethanol or methanol.

[0019] In this invention, the molecular formula R can be used. f CH2CH2-X, X1-CH2CH2R f Using fluorinated alkanes such as CH2CH2-X2 as raw materials, R fIt is a perfluoroalkyl or fluorinated alkyl group; X, X1, and X2 are I, Br, Cl, and F, respectively. In a preferred embodiment of the present invention, the fluorinated alkane is one of perfluorobutylethyl iodide, perfluorohexylethyl iodide, 1,6-diiodo-1,1,2,2,5,5,6,6-octahydrododecylfluorohexane, and 1-chloro-1,1-difluoro-2-iodoethane.

[0020] In a preferred embodiment of the present invention, the mass ratio of the fluorinated alkane to the mixed alkaline solution is 1 to 2.5:1, the reaction temperature is 40 to 85°C, and the rotation speed of the hypergravity reactor is 200 to 300 rpm.

[0021] This invention utilizes a uniquely structured supergravity reactor and optimizes process parameters. Through continuous feeding, discharging, distillation, and solvent recovery, it achieves the continuous dehydrohalogenation reaction of fluorinated alkanes with mixed alkaline solutions to prepare fluorinated olefins. This simplifies the operation, shortens the reaction time, and significantly improves reaction efficiency and product yield. It fundamentally solves the problems of low production efficiency, poor process continuity, and difficulty in recovering raw materials in existing technologies.

[0022] The working principle of the hypergravity reactor in this invention is that the rotating packing bed, driven by a motor, generates a strong hypergravity field through high-speed rotation. This field enhances the mass and heat transfer efficiency and reaction rate of the fluid reactants, thereby increasing the reaction rate. The magnitude of the hypergravity field can be controlled by adjusting the motor speed. The reactants are drawn in by the high-speed centrifugal liquid flow generated within the rotating packing bed. The hypergravity reactor of this invention consists of three chambers. The raw materials and alkali solution first enter the mixing chamber of the rotating packing bed in the material mixing reaction chamber. The rotating packing bed is a disc filled with wire mesh packing. The mixing chamber is unfilled. When the rotating packing bed rotates, the liquid is thrown out at high speed through the wire mesh packing, creating a negative pressure in the middle mixing chamber area, which draws the incoming materials into the wire mesh packing. All materials undergo thorough shearing, mixing, and reaction within the wire mesh packing, resulting in a mixing efficiency significantly higher than that of ordinary paddle agitators.

[0023] The hypergravity reactor of this invention is equipped with multiple reaction material conveying channels connecting the material separation chamber and the material mixing reaction chamber. After the fluorinated alkali raw material and the mixed alkaline solution are fully mixed and reacted in the material mixing reaction chamber, they enter the reaction chamber for further reaction. The material in the reaction chamber enters the material separation chamber along the tubular reaction material conveying channels. The reaction material conveying channels include a central channel and reaction channels. The central channel ensures that the material enters the material mixing reaction chamber, with the liquid flow direction being vertically downward. The surrounding pipes are reaction channels, ensuring that the fully mixed and reacted material enters the material separation chamber in a vertically upward direction. A hot and cold medium is circulated in the heat exchange jacket of the reaction chamber for heat exchange to control the reaction temperature. When the gas-liquid mixture containing the product enters the material separation chamber, the product is separated out from the gas outlet in gaseous form, while the remaining reaction liquid flows out of the hypergravity reactor through the liquid overflow port.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] 1. Simple structure and high reaction efficiency: This invention utilizes a supergravity reactor and optimizes process parameters to achieve continuous dehydrohalogenation reaction of fluorinated alkane raw materials with mixed alkaline solution to prepare fluorinated olefins through continuous feeding, continuous discharging, continuous distillation, and continuous solvent recovery. This simplifies the operation process, shortens the reaction time, improves reaction efficiency, and greatly enhances production capacity.

[0026] 2. High conversion rate and selectivity: The reactants in this invention are all in the liquid phase, which solves the problem of easy pipeline blockage and continuous production failure caused by solid-liquid phase reactions in the prior art. Since the reactants are in the liquid phase and a supergravity reactor is used, the process of combining supergravity mixing and tubular reaction is realized, which greatly improves the mass and heat transfer efficiency and significantly improves the raw material conversion rate and product selectivity. The conversion rate is 100% and the selectivity is over 99%, with a maximum of 99.9%.

[0027] 3. Safe and controllable: This invention utilizes the efficient mass and heat transfer characteristics of a hypergravity reactor to remove the heat generated by the reaction in a timely manner. The powerful hypergravity field generated by the high-speed rotation of the rotating packed bed improves the mass transfer and reaction efficiency of the fluid reactants in the hypergravity field. The material ratio is stable and can make effective contact, resulting in uniform temperature distribution during the reaction process. The ability to control the reaction smoothly is significantly enhanced, thus improving the safety of the reaction.

[0028] 4. Green and environmentally friendly, with low production costs, suitable for industrialization. This invention adopts a method combining reaction and continuous distillation, which can ensure the efficient recovery of unreacted raw materials and the efficient purification of products, effectively reducing production costs. In addition, this invention achieves continuous separation of solvent and by-products by setting up a mixed alkali recovery device, which not only greatly improves the solvent recovery rate, but also significantly improves the quality of by-products, further reducing the emission of waste gas, wastewater, and solid waste, and lowering costs. At the same time, the continuous preparation device for fluorinated olefins of this invention is small in size, occupies less space, is more efficient, has a larger production capacity, and is easy to industrialize. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the continuous preparation apparatus for fluorinated olefins according to the present invention;

[0030] Figure 2 This is a schematic diagram of the structure of the supergravity reactor in this invention.

[0031] In the diagram, 1 is the high-gravity reactor, 2 is the ribbon dryer, 3 is the solvent storage tank, 4 is the alkali preparation tank, 5 is the alkali storage tank, 6 is the raw material storage tank, 7 is the first heat exchanger, 8 is the second heat exchanger, 9 is the distillation column, 10 is the product storage tank, 11 is the solvent recovery pump, 12 is the alkali circulation pump, 13 is the gas outlet, 14 is the raw material feed pipe, 15 is the alkali feed pipe, 16 is the liquid overflow port, 17 is the shell, 18 is the hot / cold medium outlet, 19 is the hot / cold medium inlet, 20 is the reactant conveying channel, 21 is the material separation chamber, 22 is the heat exchange jacket, 23 is the material mixing reaction chamber, 24 is the packing chamber, 25 is the mixing chamber, 26 is the rotating shaft, 27 is the raw material metering pump, 28 is the alkali metering pump, 29 is the first isolation component, and 30 is the second isolation component. Detailed Implementation

[0032] As shown in the attached figures, the continuous preparation apparatus for fluorinated olefins of the present invention includes a hypergravity reactor 1, a fluorinated alkane supply device consisting of a raw material storage tank 6, a raw material metering pump 27, and a first heat exchanger 7, a mixed alkali supply device consisting of an alkali storage tank 5, an alkali metering pump 28, and a second heat exchanger 8, a mixed alkali recovery device consisting of a ribbon dryer 2, a solvent storage tank 3, a solvent recovery pump 11, an alkali preparation tank 4, and an alkali circulation pump 12, a distillation column 9, and a product storage tank 10. The hypergravity reactor 1 includes a shell 17, within which a first isolation member 29 and a second isolation member 30 are provided to separate the shell 1. Internally, the material separation chamber 21 is divided into a material separation chamber 21, a reaction chamber, and a material mixing reaction chamber 23 from top to bottom. Multiple reaction material conveying channels 20 connecting the material separation chamber 21 and the material mixing reaction chamber 23 are provided on the first isolation component 29, the reaction chamber, and the second isolation component 30. The top of the material separation chamber 21 is equipped with a gas outlet 13, a raw material feed pipe 14, and an alkali feed pipe 15. The gas outlet 13 is connected to the feed inlet of the distillation column 9. The product outlet of the distillation column 9 is connected to the inlet of the product storage tank 10. The bottom liquid outlet of the distillation column 9 is connected to the circulation inlet of the raw material storage tank 6. The sides of the material separation chamber 21 are equipped with… A liquid overflow port 16 is provided, which is connected to the inlet of the ribbon dryer 2. The liquid phase outlet of the ribbon dryer 2 is connected to the inlet of the solvent storage tank 3. The outlet of the solvent storage tank 3 is connected to the inlet of the solvent recovery pump 11. The outlet of the solvent recovery pump 11 is connected to the inlet of the alkali preparation tank 4. The outlet of the alkali preparation tank 4 is connected to the inlet of the alkali circulation pump 12. The outlet of the alkali circulation pump 12 is connected to the inlet of the alkali storage tank 5. A rotating packed bed is provided inside the material mixing reaction chamber 23. A mixing chamber 25 is provided at the center of the rotating packed bed. A packing chamber 24 for placing packing is provided around the mixing chamber 25. The packed bed is connected to the motor via a rotating shaft 26. The material outlet of the first heat exchanger 7 is connected to the mixing chamber 25 via a raw material feed pipe 14. The material outlet of the second heat exchanger 8 is connected to the mixing chamber 25 via an alkali feed pipe 15. The raw material feed pipe 14 and the alkali feed pipe 15 pass through the top of the shell 17, through the first isolation member 29 and the second isolation member 30, and are connected to the mixing chamber 25. The reaction chamber is equipped with a heat exchange jacket 22. The heat exchange jacket 22 is equipped with a hot and cold medium outlet 18 and a hot and cold medium inlet 19. Hot and cold medium is introduced into the heat exchange jacket 22 through the hot and cold medium outlet 18 and the hot and cold medium inlet 19 to control the reaction temperature.

[0033] The process flow for the continuous preparation of fluorinated olefins using the above-mentioned apparatus is as follows:

[0034] (1) Fluorinated alkanes are continuously fed into the supergravity reactor 1 through the raw material feed pipe 14, and mixed alkaline solution is continuously fed into the supergravity reactor 1 through the alkaline solution feed pipe 15. The reactants are fully mixed and reacted in the material mixing reaction chamber 23 under the centrifugal action of the rotating packed bed.

[0035] (2) The reacted material enters the reaction chamber through the reaction material conveying channel 20 under the centrifugal action of the rotating packed bed. The reacted material further reacts in the reaction material conveying channel 20 and exchanges heat with the refrigerant in the heat exchange jacket 22 to control the reaction temperature.

[0036] (3) The gas-liquid mixture reaction product containing fluorinated olefins enters the material separation chamber 21 through the reaction material conveying channel 20. The fluorinated olefins are separated out from the gas outlet 13 in gas phase and enter the distillation column 9. The remaining liquid material enters the ribbon dryer 2 through the liquid overflow port 16 for separation. The solvent obtained by separation is condensed and enters the alkali preparation tank 4 through the solvent storage tank 3 and the solvent recovery pump 11 in sequence. After adding alkali or replenishing solvent, it returns to the alkali storage tank 5 through the alkali circulation pump 12. The solid halide salt by-product separated at the bottom of the ribbon dryer 2 is packaged and sold separately.

[0037] (4) The purified product enters the product storage tank 10 through the product outlet of the distillation tower 9.

[0038] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0039] Example 1: A continuous preparation apparatus for fluorinated olefins includes a centrifugal reactor 1 (cylindrical, effective volume 200L, made of 316L stainless steel), a fluorinated alkane supply device consisting of a raw material storage tank 6, a raw material metering pump 27, and a first heat exchanger 7, a mixed alkali supply device consisting of an alkali storage tank 5, an alkali metering pump 28, and a second heat exchanger 8, a mixed alkali recovery device consisting of a ribbon dryer 2, a solvent storage tank 3, a solvent recovery pump 11, an alkali preparation tank 4, and an alkali circulation pump 12, a distillation column 9, and a product storage tank 10. The centrifugal reactor 1 includes a shell 17, within which a first isolation member 29 and a second isolation member are disposed. The separator 30 divides the interior of the shell 17 from top to bottom into a material separation chamber 21, a reaction chamber, and a material mixing reaction chamber 23. Eighteen reaction material conveying channels 20, connecting the material separation chamber 21 and the material mixing reaction chamber 23, are provided on the first separator 29, the reaction chamber, and the second separator 30. These eighteen channels are evenly distributed axially. The top of the material separation chamber 21 is equipped with a gas outlet 13, a raw material feed pipe 14, and an alkali feed pipe 15. The gas outlet 13 is connected to the feed inlet of the distillation column 9. The product outlet of the distillation column 9 is connected to the inlet of the product storage tank 10. The bottom liquid outlet of the distillation column 9 is connected to the raw material storage tank 6. The material separation chamber 21 is connected to the circulating inlet. A liquid overflow port 16 is located on the side of the material separation chamber 21. The liquid overflow port 16 is connected to the inlet of the ribbon dryer 2. The liquid phase outlet of the ribbon dryer 2 is connected to the inlet of the solvent storage tank 3. The outlet of the solvent storage tank 3 is connected to the inlet of the solvent recovery pump 11. The outlet of the solvent recovery pump 11 is connected to the inlet of the alkali preparation tank 4. The outlet of the alkali preparation tank 4 is connected to the inlet of the alkali circulation pump 12. The outlet of the alkali circulation pump 12 is connected to the inlet of the alkali storage tank 5. A rotating packed bed is installed inside the material mixing reaction chamber 23. A mixing chamber 25 is located at the center of the rotating packed bed. Stainless steel wire is placed around the mixing chamber 25. The packing chamber 24 of the mesh packing is connected to the motor via the rotating shaft 26. The material outlet of the first heat exchanger 7 is connected to the mixing chamber 25 via the raw material feed pipe 14. The material outlet of the second heat exchanger 8 is connected to the mixing chamber 25 via the alkali feed pipe 15. The raw material feed pipe 14 and the alkali feed pipe 15 pass through the top of the shell 17, through the first isolation member 29 and the second isolation member 30, and are connected to the mixing chamber 25. The reaction chamber is equipped with a heat exchange jacket 22. The heat exchange jacket 22 is equipped with a hot and cold medium outlet 18 and a hot and cold medium inlet 19. Hot and cold medium is introduced into the heat exchange jacket 22 through the hot and cold medium outlet 18 and the hot and cold medium inlet 19 to control the reaction temperature.

[0040] The above-described apparatus is used to continuously produce perfluorobutylethylene from perfluorobutylethyl iodine, with potassium iodide as a byproduct. The reaction principle is as follows:

[0041] C4F9CH2CH2I+KOH→C4F9CH=CH2+KI+H2O

[0042] The process parameters are:

[0043] The mixed alkaline solution is prepared according to the following mass percentages: 40% KOH, 35% water, and 25% methanol.

[0044] Perfluorobutyl ethyl iodine (content 99.50wt%) was continuously fed into a 200L effective volume hypergravity reactor at a flow rate of 50kg / h and a mixed alkaline solution at a flow rate of 31.44kg / h. The reaction temperature was controlled at 40℃ and the speed of the hypergravity reactor was 200 rpm.

[0045] Reaction results:

[0046] The final product obtained after distillation has a perfluorobutylethylene content of 99.95%, an average hourly yield of 32.56 kg / h, a product yield of 99.5%, a perfluorobutylethyl iodine conversion rate of 100%, and a production capacity of 780 kg / day. However, using a batch reactor yields a product yield of 96% and a conversion rate of 99.5%, but some raw materials are lost and cannot be recovered; a single 200L reactor has a production capacity of 315 kg / day.

[0047] The by-product KI has a moisture content of <1% and a purity of >90%, and can be sold as a premium product.

[0048] The equipment and pipelines are free from blockages and siltation. Solvent water and methanol are fully recovered, with no wastewater or solid waste discharge.

[0049] Example 2: A continuous preparation apparatus for fluorinated olefins, comprising a hypergravity reactor 1 (cylindrical, effective volume 200L, made of 316L stainless steel), a fluorinated alkane supply device consisting of a raw material storage tank 6, a raw material metering pump 27, and a first heat exchanger 7, a mixed alkali supply device consisting of an alkali storage tank 5, an alkali metering pump 28, and a second heat exchanger 8, a mixed alkali recovery device consisting of a ribbon dryer 2, a solvent storage tank 3, a solvent recovery pump 11, an alkali preparation tank 4, and an alkali circulation pump 12, a distillation column 9, and a product storage tank 10. The hypergravity reactor 1 includes a shell 17, within which a first isolation member 29 and a second isolation member are disposed. The separation component 30 divides the interior of the shell 17 from top to bottom into a material separation chamber 21, a reaction chamber, and a material mixing reaction chamber 23. Sixteen reaction material conveying channels 20, connecting the material separation chamber 21 and the material mixing reaction chamber 23, are provided on the first separation component 29, the reaction chamber, and the second separation component 30. These sixteen channels are evenly distributed axially. The top of the material separation chamber 21 is equipped with a gas outlet 13, a raw material feed pipe 14, and an alkali feed pipe 15. The gas outlet 13 is connected to the feed inlet of the distillation column 9. The product outlet of the distillation column 9 is connected to the inlet of the product storage tank 10. The bottom liquid outlet of the distillation column 9 is connected to the raw material storage tank 6. The material separation chamber 21 is connected to the circulating inlet. A liquid overflow port 16 is located on the side of the material separation chamber 21. The liquid overflow port 16 is connected to the inlet of the ribbon dryer 2. The liquid phase outlet of the ribbon dryer 2 is connected to the inlet of the solvent storage tank 3. The outlet of the solvent storage tank 3 is connected to the inlet of the solvent recovery pump 11. The outlet of the solvent recovery pump 11 is connected to the inlet of the alkali preparation tank 4. The outlet of the alkali preparation tank 4 is connected to the inlet of the alkali circulation pump 12. The outlet of the alkali circulation pump 12 is connected to the inlet of the alkali storage tank 5. A rotating packed bed is installed inside the material mixing reaction chamber 23. A mixing chamber 25 is located at the center of the rotating packed bed. Stainless steel wire is placed around the mixing chamber 25. The packing chamber 24 of the mesh packing is connected to the motor via the rotating shaft 26. The material outlet of the first heat exchanger 7 is connected to the mixing chamber 25 via the raw material feed pipe 14. The material outlet of the second heat exchanger 8 is connected to the mixing chamber 25 via the alkali feed pipe 15. The raw material feed pipe 14 and the alkali feed pipe 15 pass through the top of the shell 17, through the first isolation member 29 and the second isolation member 30, and are connected to the mixing chamber 25. The reaction chamber is equipped with a heat exchange jacket 22. The heat exchange jacket 22 is equipped with a hot and cold medium outlet 18 and a hot and cold medium inlet 19. Hot and cold medium is introduced into the heat exchange jacket 22 through the hot and cold medium outlet 18 and the hot and cold medium inlet 19 to control the reaction temperature.

[0050] The above-described apparatus is used to continuously produce perfluorohexylethylene from perfluorohexylethyl iodine, with potassium iodide as a byproduct. The reaction principle is as follows:

[0051] C6F 13 CH2CH2I + KOH → C6F 13CH=CH2+KI+H2O

[0052] The process parameters are:

[0053] The mixed alkaline solution is prepared by mass percentage, consisting of 35% water, 20% methanol, and 45% water.

[0054] Perfluorohexylethyl iodine (content 99.0wt%) was continuously fed into a 200L effective volume hypergravity reactor at a flow rate of 50kg / h and a mixed alkaline solution at a flow rate of 24.81kg / h. The reaction temperature was controlled at 55℃ and the speed of the hypergravity reactor was 250 rpm.

[0055] Reaction results:

[0056] The final product obtained after distillation has a perfluorohexylethylene content of 99.95%, an average hourly yield of 36.28 kg / h, a product yield of 99.9%, a perfluorohexylethyl iodine conversion rate of 100%, and a production capacity of 870 kg / day. However, using a batch reactor yields a product yield of 97% and a conversion rate of 99.5%, but also suffers from some unrecoverable raw material loss, with a single 200L reactor having a capacity of 300 kg / day.

[0057] The by-product KI has a moisture content of <1% and a purity of >90%, and can be sold as a premium product.

[0058] The equipment and pipelines are free from blockages and siltation. Solvent water and methanol are fully recovered, with no wastewater or solid waste discharge.

[0059] Example 3: A continuous preparation apparatus for fluorinated olefins, comprising a hypergravity reactor 1 (cylindrical, effective volume 200L, made of 316L stainless steel), a fluorinated alkane supply device consisting of a raw material storage tank 6, a raw material metering pump 27, and a first heat exchanger 7, a mixed alkali supply device consisting of an alkali storage tank 5, an alkali metering pump 28, and a second heat exchanger 8, a mixed alkali recovery device consisting of a ribbon dryer 2, a solvent storage tank 3, a solvent recovery pump 11, an alkali preparation tank 4, and an alkali circulation pump 12, a distillation column 9, and a product storage tank 10. The hypergravity reactor 1 includes a shell 17, within which a first isolation member 29 and a second isolation member are disposed. The separator 30 divides the interior of the shell 17 from top to bottom into a material separation chamber 21, a reaction chamber, and a material mixing reaction chamber 23. Twenty reaction material conveying channels 20, connecting the material separation chamber 21 and the material mixing reaction chamber 23, are provided on the first separator 29, the reaction chamber, and the second separator 30. These twenty channels are evenly distributed axially. The top of the material separation chamber 21 is equipped with a gas outlet 13, a raw material feed pipe 14, and an alkali feed pipe 15. The gas outlet 13 is connected to the feed inlet of the distillation column 9. The product outlet of the distillation column 9 is connected to the inlet of the product storage tank 10. The bottom liquid outlet of the distillation column 9 is connected to the raw material storage tank 6. The material separation chamber 21 is connected to the circulating inlet. A liquid overflow port 16 is located on the side of the material separation chamber 21. The liquid overflow port 16 is connected to the inlet of the ribbon dryer 2. The liquid phase outlet of the ribbon dryer 2 is connected to the inlet of the solvent storage tank 3. The outlet of the solvent storage tank 3 is connected to the inlet of the solvent recovery pump 11. The outlet of the solvent recovery pump 11 is connected to the inlet of the alkali preparation tank 4. The outlet of the alkali preparation tank 4 is connected to the inlet of the alkali circulation pump 12. The outlet of the alkali circulation pump 12 is connected to the inlet of the alkali storage tank 5. A rotating packed bed is installed inside the material mixing reaction chamber 23. A mixing chamber 25 is located at the center of the rotating packed bed. Stainless steel wire is placed around the mixing chamber 25. The packing chamber 24 of the mesh packing is connected to the motor via the rotating shaft 26. The material outlet of the first heat exchanger 7 is connected to the mixing chamber 25 via the raw material feed pipe 14. The material outlet of the second heat exchanger 8 is connected to the mixing chamber 25 via the alkali feed pipe 15. The raw material feed pipe 14 and the alkali feed pipe 15 pass through the top of the shell 17, through the first isolation member 29 and the second isolation member 30, and are connected to the mixing chamber 25. The reaction chamber is equipped with a heat exchange jacket 22. The heat exchange jacket 22 is equipped with a hot and cold medium outlet 18 and a hot and cold medium inlet 19. Hot and cold medium is introduced into the heat exchange jacket 22 through the hot and cold medium outlet 18 and the hot and cold medium inlet 19 to control the reaction temperature.

[0060] Using the above-described apparatus, 1,6-divinylperfluorohexane is continuously prepared from 1,6-diiodo-1,1,2,2,5,5,6,6-octahydrododecylfluorohexane, with potassium iodide as a byproduct. The reaction principle is as follows:

[0061] ICH2CH2C6F12 CH2CH2I + 2KOH → CH2=CHC6F 12 CH=CH2+KI+H2O

[0062] The process parameters are:

[0063] The mixed alkaline solution is prepared according to the following mass percentages: 25% KOH, 40% water, and 35% methanol.

[0064] Perfluorohexylethyl iodine (content 99.0%) was continuously fed into a 200L effective volume hypergravity reactor at a flow rate of 50kg / h and a mixed alkaline solution at a flow rate of 38.56kg / h. The reaction temperature was controlled at 60℃ and the speed of the hypergravity reactor was 300 rpm.

[0065] Reaction results:

[0066] The final product obtained after distillation has a 1,6-divinylperfluorohexane content of 99.95%, an average hourly yield of 28.44 kg / h, a product yield of 99.0%, a perfluorohexylethyl iodine conversion rate of 100%, and a production capacity of 680 kg / day. However, using a batch reactor yields a product yield of 90% and a conversion rate of 99.5%, but also suffers from some unrecoverable raw material loss, with a single 200L reactor having a capacity of 250 kg / day.

[0067] The by-product KI has a moisture content of <1% and a purity of >90%, and can be sold as a premium product.

[0068] The equipment and pipelines are free from blockages and siltation. Solvent water and methanol are fully recovered, with no wastewater or solid waste discharge.

[0069] Example 4: A continuous preparation apparatus for fluorinated olefins, comprising a hypergravity reactor 1 (cylindrical, 200L volume, made of 316L stainless steel), a fluorinated alkane supply device consisting of a raw material storage tank 6, a raw material metering pump 27, and a first heat exchanger 7, a mixed alkali supply device consisting of an alkali storage tank 5, an alkali metering pump 28, and a second heat exchanger 8, a mixed alkali recovery device consisting of a ribbon dryer 2, a solvent storage tank 3, a solvent recovery pump 11, an alkali preparation tank 4, and an alkali circulation pump 12, a distillation column 9, and a product storage tank 10. The hypergravity reactor 1 includes a shell 17, within which a first isolation member 29 and a second isolation member are disposed. Component 30 divides the interior of shell 17 from top to bottom into a material separation chamber 21, a reaction chamber, and a material mixing reaction chamber 23. The first isolation component 29, the reaction chamber, and the second isolation component 30 are equipped with twelve reaction material conveying channels 20 connecting the material separation chamber 21 and the material mixing reaction chamber 23. These twelve reaction material conveying channels 20 are evenly distributed axially. The top of the material separation chamber 21 is equipped with a gas outlet 13, a raw material feed pipe 14, and an alkali feed pipe 15. The gas outlet 13 is connected to the feed inlet of the distillation column 9. The product outlet of the distillation column 9 is connected to the inlet of the product storage tank 10. The bottom liquid outlet of the distillation column 9 is connected to the circulation outlet of the raw material storage tank 6. The material separation chamber 21 is connected to the inlet of the spiral dryer 2. A liquid overflow port 16 is located on the side of the material separation chamber 21. The liquid overflow port 16 is connected to the inlet of the spiral dryer 2. The liquid phase outlet of the spiral dryer 2 is connected to the inlet of the solvent storage tank 3. The outlet of the solvent storage tank 3 is connected to the inlet of the solvent recovery pump 11. The outlet of the solvent recovery pump 11 is connected to the inlet of the alkali preparation tank 4. The outlet of the alkali preparation tank 4 is connected to the inlet of the alkali circulation pump 12. The outlet of the alkali circulation pump 12 is connected to the inlet of the alkali storage tank 5. A rotating packed bed is installed inside the material mixing reaction chamber 23. A mixing chamber 25 is located at the center of the rotating packed bed. Stainless steel wire is placed around the mixing chamber 25. The packing chamber 24 of the mesh packing is connected to the motor via the rotating shaft 26. The material outlet of the first heat exchanger 7 is connected to the mixing chamber 25 via the raw material feed pipe 14. The material outlet of the second heat exchanger 8 is connected to the mixing chamber 25 via the alkali feed pipe 15. The raw material feed pipe 14 and the alkali feed pipe 15 pass through the top of the shell 17, through the first isolation member 29 and the second isolation member 30, and are connected to the mixing chamber 25. The reaction chamber is equipped with a heat exchange jacket 22. The heat exchange jacket 22 is equipped with a hot and cold medium outlet 18 and a hot and cold medium inlet 19. Hot and cold medium is introduced into the heat exchange jacket 22 through the hot and cold medium outlet 18 and the hot and cold medium inlet 19 to control the reaction temperature.

[0070] Using the above-described apparatus, 1,1-difluoroiodoethylene is continuously prepared from 1-chloro-1,1-difluoro-2-iodoethane as a raw material, with potassium iodide as a byproduct.

[0071] The reaction principle is as follows:

[0072] ClCF2CH2I+KOH→CF2=CHI+KCl+H2O

[0073] The process parameters are:

[0074] The mixed alkaline solution is prepared according to the following mass percentages: 48% KOH and 52% water (commercially available 48% industrial-grade KOH aqueous solution).

[0075] 1-Chloro-1,1-difluoro-2-iodoethane (content 99.0%) was continuously fed into a 200L effective volume centrifugal reactor at a flow rate of 50kg / h, and a mixed alkaline solution was continuously fed into the reactor at a flow rate of 27kg / h. The reaction temperature was controlled at 85℃ and the centrifugal reactor rotation speed was 300 rpm.

[0076] Reaction results:

[0077] The final product obtained after distillation has a 1,1-difluoroiodoethylene content of 99.95%, an average hourly yield of 37.56 kg / h, a product yield of 99%, a 100% conversion rate of 1-chloro-1,1-difluoro-2-iodoethane, and a production capacity of 900 kg / day. In contrast, using a batch reactor yields only 63% product and 90% conversion, with significant unrecoverable raw material losses, and a single 200L reactor has a capacity of only 250 kg / day.

[0078] The by-product KCl has a water content of <1% and a purity of >95%, and can be sold as a premium product.

[0079] The equipment and pipelines are free from blockages and siltation. All solvent water is fully recycled, resulting in no wastewater or solid waste discharge.

Claims

1. A continuous production apparatus for fluorinated olefins, comprising a reactor, a fluorinated alkane supply device, a mixed alkali supply device, a distillation column, and a product storage tank, characterized in that, The reactor is a hypergravity reactor, comprising a shell. A first isolation member and a second isolation member are provided within the shell, dividing the interior of the shell from top to bottom into a material separation chamber, a reaction chamber, and a material mixing reaction chamber. Multiple reaction material conveying channels connecting the material separation chamber and the material mixing reaction chamber are provided on the first isolation member, the reaction chamber, and the second isolation member. A gas outlet is provided at the top of the material separation chamber, and a liquid overflow outlet is provided on the side of the material separation chamber. The gas outlet is connected to the distillation column, and the product outlet of the distillation column is connected to the product storage tank. A rotating packed bed is provided inside the material mixing reaction chamber, with a mixing chamber at the center of the rotating packed bed. Packing chambers for placing packing material are provided around the mixing chamber. A fluorinated alkali supply device is connected to the mixing chamber through a raw material feed pipe, and a mixed alkali supply device is connected to the mixing chamber through an alkali feed pipe.

2. The continuous preparation apparatus for fluorinated olefins according to claim 1, characterized in that, The preparation apparatus also includes a mixed alkali solution recovery device, and the liquid overflow port is connected to the mixed alkali solution recovery device.

3. The continuous preparation apparatus for fluorinated olefins according to claim 2, characterized in that, The mixed alkali recovery device is connected to the mixed alkali supply device.

4. The continuous preparation apparatus for fluorinated olefins according to claim 1, characterized in that, The raw material feed pipe and the alkali feed pipe are connected to the mixing chamber through the first isolation member and the second isolation member from the top of the shell.

5. The continuous preparation apparatus for fluorinated olefins according to claim 1, characterized in that, The reaction material conveying channels are uniformly distributed along the axial direction.

6. A method for the continuous preparation of fluorinated olefins using the apparatus of claim 1, characterized in that, Includes the following steps: (1) Fluorinated alkanes are continuously fed into the supergravity reactor through the raw material feed pipe, and mixed alkaline solution is continuously fed into the supergravity reactor through the alkaline solution feed pipe. The reactants are fully mixed and reacted under the centrifugal action of the rotating packed bed. (2) The reacted material is centrifuged by the rotating packed bed and enters the reaction chamber through the reactant conveying channel for further reaction; (3) The gas-liquid mixture reaction product containing fluorinated olefins enters the material separation chamber through the reaction material conveying channel. The fluorinated olefins are separated from the gas outlet in gaseous form and enter the distillation tower. The remaining liquid material enters the mixed alkali recovery device through the liquid overflow port. (4) The purified product enters the product storage tank through the product outlet of the distillation tower.

7. The method for continuous preparation of fluorinated olefins according to claim 6, characterized in that, The preparation apparatus also includes a mixed alkali solution recovery device, through which unreacted mixed alkali solution enters the mixed alkali solution recovery device via the liquid overflow port.

8. The method for continuous preparation of fluorinated olefins according to claim 6, characterized in that, The mixed alkaline solution is a mixture of alkali, alcohol and / or water, wherein the mass percentage of alkali in the mixture is 20-50%; the alkali is KOH or NaOH; and the alcohol is ethanol or methanol.

9. The method for continuous preparation of fluorinated olefins according to claim 6, characterized in that, The fluorinated alkane is one of perfluorobutyl ethyl iodine, perfluorohexyl ethyl iodine, 1,6-diiodo-1,1,2,2,5,5,6,6-octahydrododecylhexane, and 1-chloro-1,1-difluoro-2-iodoethane.

10. The method for continuous preparation of fluorinated olefins according to claim 6, characterized in that, The mass ratio of the fluorinated alkali to the mixed alkaline solution is 1-2.5:1, the reaction temperature is 40-85℃, and the rotation speed of the hypergravity reactor is 200-300 rpm.

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