Process and apparatus for the production of trifluoroacetamides

Abstract

The application is a production method and equipment of trifluoroacetamide, and relates to the technical field of trifluoroacetamide production equipment, comprising a rack, a premixing box body on the top of the rack is provided with a feeding mechanism, a premixing inner cavity is arranged in the premixing box body, four cavity partition plates are fixedly installed on the outer wall of the central shaft in the premixing inner cavity, and the premixing inner cavity is divided into four equal-volume distribution cavities; an annular seat is arranged on the outer side of the premixing box body, one end of the central shaft is arranged in the inner part of the annular seat and rotationally matched with the annular seat, the other end of the central shaft is fixedly connected with a power driving shaft, a driving mechanism is installed on the outer end part of the power driving shaft, and the driving mechanism is used for intermittently rotating the power driving shaft by 90 degrees. The application can complete the premixing operation of four different molar ratio formulas in parallel, not only greatly improves the equipment utilization and production efficiency, but also gives the production line strong flexible output capacity and can quickly respond to the production demand of trifluoroacetamide products with different purity grades.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of trifluoroacetamide production equipment, and specifically discloses a production method and equipment for trifluoroacetamide. BACKGROUND

[0002] In the continuous production of trifluoroacetamide, the pre-mixing of ethyl trifluoroacetate and tetrahydrofuran is a crucial pretreatment step, and the core purpose is to create optimal conditions for the subsequent efficient and safe reaction with anhydrous liquid ammonia. The above-mentioned ethyl trifluoroacetate, tetrahydrofuran, and anhydrous liquid ammonia are all in liquid state, and the storage temperature of anhydrous liquid ammonia is generally between -33°C and -43°C. After mixing the three into a homogeneous solution, the flow fluctuations that may be caused by multiple feed streams can be effectively eliminated, ensuring the accurate and constant molar ratio with liquid ammonia, and laying a foundation for obtaining high-purity and high-yield products. Therefore, the above-mentioned pre-mixing step is a simple physical process that paves the way for a complex chemical reaction, and is a key link to realize the safety, controllability, and efficiency of the entire production process.

[0003] The invention with publication number CN116571181A discloses a synthesis process for trifluoroacetamide. The equipment used in the process includes a case, a protective cylinder, a reaction tank, a first shell, a second shell, etc. The first shell has a vertical rod and a spiral piece, and the outer wall has a first electric heating piece and a liquid outlet hole for preheating ethyl trifluoroacetate. The second shell has a connecting pipe and an arc-shaped piece, and the outer wall has a second electric heating piece. Ammonia gas is delivered through a conversion mechanism to react with ethyl trifluoroacetate. After a certain period of reaction, the corrosion-resistant pump makes the reaction liquid backflow to improve the conversion rate. After synthesis is complete, the first and second shells can be switched by a rotating mechanism, and then washed with water and dried.

[0004] In the disclosed patent technology, preheating ethyl trifluoroacetate can improve the conversion rate and speed up the production rate of trifluoroacetamide. If the above-mentioned existing technology is used to pre-mix the raw materials of trifluoroacetamide, there are significant limitations. Due to the single pre-mixing tank, only one molar ratio scheme of the raw materials can be used in a single production cycle. This rigid production mode seriously restricts process optimization and product diversification. If different ratio schemes need to be switched, the equipment must be thoroughly cleaned and the parameters must be re-adjusted, which is a tedious and time-consuming process, resulting in low production efficiency and serious resource waste. More importantly, it is impossible to compare the reaction effects of multiple ratio schemes under the same working conditions, which greatly prolongs the process development and optimization period, making it difficult to quickly respond to market demand for different purity grade products. SUMMARY

[0005] In view of the low production efficiency caused by the rigid production mode in the current trifluoroacetamide production process, the present application provides a production method and equipment for trifluoroacetamide.

[0006] To solve the above problems, in a first aspect, the present application provides the following technical solutions:

[0007] A trifluoroacetamide production equipment, comprising a rack, a premixing box body fixedly installed on the rack, a feeding mechanism arranged on the top of the premixing box body, a premixing inner cavity arranged in the premixing box body, the feeding mechanism being used for conveying ethyl trifluoroacetate, anhydrous liquid ammonia and tetrahydrofuran into the premixing inner cavity, a rotatable central shaft arranged in the premixing inner cavity, four equidistantly arranged partition cavity plates fixedly installed on the outer wall of the central shaft, the outer edge of the partition cavity plate being in sliding fit with the inner cavity wall of the premixing inner cavity, the four equidistantly arranged partition cavity plates separating the premixing inner cavity into four equal-volume distribution cavities, an annular seat fixedly connected with the rack arranged on the outer side of the premixing box body, one end of the central shaft being arranged in the inner part of the annular seat and in rotational fit with the annular seat, a power driving shaft fixedly connected with the other end of the central shaft, a driving mechanism installed on the outer end of the power driving shaft, the driving mechanism being used for intermittently rotating the power driving shaft by 90°, and one of the distribution cavities being in communication with the feeding mechanism after the central shaft rotates by 90°.

[0008] Preferably, the feeding mechanism comprises a converging cross pipe, a first flow-through vertical pipe and a second flow-through vertical pipe fixedly installed on the bottom of the converging cross pipe, the bottom ends of the first flow-through vertical pipe and the second flow-through vertical pipe being in communication with the premixing inner cavity, a pipe disc fixedly installed on one end of the converging cross pipe, a damping pipe, a first high-pressure steel pipe and a second high-pressure steel pipe installed on the pipe disc, the damping pipe being connected with a third high-pressure steel pipe used for conveying ethyl trifluoroacetate, and the first high-pressure steel pipe and the second high-pressure steel pipe being respectively used for conveying anhydrous liquid ammonia and tetrahydrofuran.

[0009] Preferably, a first port and a second port are arranged on the end of the converging cross pipe away from the pipe disc, the ports of the first port and the second port being arranged in radial perpendicularity, a pressure relief pipe fixedly installed on the pipe wall of the converging cross pipe is arranged on the side of the first port, and a pressure valve table is installed on the pipeline of the first high-pressure steel pipe.

[0010] Preferably, bearing sealing rings are installed on the two sides of the premixing box body, the bearing sealing rings being sleeved on the periphery of the central shaft, support seats fixedly connected with the rack are arranged on the two sides of the premixing box body, rotating bases are fixedly installed on the two support seats, two rotating wheels are rotatably installed on each rotating base, a support ring is fixedly sleeved on the outer wall of the central shaft, and the outer wall of the rotating wheel is in sliding fit with the outer wall of the support ring.

[0011] Preferably, the gantry is fixedly provided with a first bearing seat and a second bearing seat, the first bearing seat is fixedly provided with a vertical plate, the outer wall of the power driven shaft is in rotating fit with the top end of the vertical plate, the second bearing seat is fixedly provided with a three-phase asynchronous motor, and the output end of the three-phase asynchronous motor is in transmission fit with the driving mechanism.

[0012] Preferably, the driving mechanism comprises a cam disc, the disc surface on one side of the cam disc is connected with the output end of the three-phase asynchronous motor, the cam disc is provided with a groove on one side, the end of the power driven shaft is fixedly provided with a cross support, the four outer sides of the cross support are all fixedly provided with cylinders, the outer walls of two of the cylinders are in sliding fit with the inner walls of the groove, and the other two cylinders are arranged outside the cam disc.

[0013] Preferably, the disc surface on the side of the cam disc close to the cross support is provided with a heart-shaped protrusion, the groove is arranged outside the heart-shaped protrusion, the groove is a heart-shaped annular groove structure, the two outer edges of the groove are both provided with symmetrically arranged through grooves, the opening size of the through grooves is matched with the diameter size of the cylinders, the side portions of the two through grooves are both provided with inclined surfaces arranged on the cam disc, and the inclined surfaces are in sliding fit with the outer walls of the cylinders.

[0014] Preferably, the bottom of the premixing box body is fixedly provided with a discharging box, the top end of the discharging box is in communication with the premixing inner cavity, the discharging box is in a funnel structure, and the bottom end of the discharging box is arranged inside the gantry and is fixedly connected with a third flow vertical pipe.

[0015] In another aspect, the application also provides a production method of trifluoroacetamide, which comprises:

[0016] S1: ethyl trifluoroacetate is conveyed into one of the premixing inner cavities through the third high-pressure steel pipe, the flow of the ethyl trifluoroacetate is stabilized through the damping pipe, anhydrous liquid ammonia and tetrahydrofuran are respectively conveyed into the above-mentioned cavity through the first high-pressure steel pipe and the second high-pressure steel pipe, and the molar ratios of the ethyl trifluoroacetate, the anhydrous liquid ammonia and the tetrahydrofuran in the four cavities are all different;

[0017] S2: the cam disc is continuously and uniformly rotated through the three-phase asynchronous motor, so that the two cylinders slide in the groove, the cylinders can slide out of the groove through the through grooves, so that the central shaft is intermittently rotated, each time the rotation is 90°, each cavity stays below the feeding mechanism for a predetermined time, the conveying of the ethyl trifluoroacetate, the anhydrous liquid ammonia and the tetrahydrofuran is completed, and the partition plate can ensure that the materials in the cavities are independent and prevent cross contamination;

[0018] S3: In the intermittent rotation process of the center shaft, the ethyl trifluoroacetate, anhydrous liquid ammonia and tetrahydrofuran are premixed into four kinds of trifluoroacetamide with four molar ratios in the four separate material cavities, and the four kinds of trifluoroacetamide with four molar ratios in the four separate material cavities are discharged through the discharge box and the third flow-through vertical pipe.

[0019] Preferably, the four molar ratio schemes of the four kinds of trifluoroacetamide in the four separate material cavities are:

[0020] Scheme one: ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.0:4.5;

[0021] Scheme two: ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.2:2.3;

[0022] Scheme three: ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.6:9.2;

[0023] Scheme four: ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:0.8:4.5.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] 1、The present application realizes the precise indexing motion of the intermittent rotation of the center shaft by 90° by setting four independent separate material cavities in the premixing box body separated by the center shaft and four separate cavity plates, and cooperating with the precise driving mechanism composed of the cam disc, the cross bracket and the cylinder, The above structure makes the four separate material cavities flow to the lower side of the feeding mechanism in turn, so as to continuously receive raw materials with different proportions, and each separate material cavity is equivalent to an independent micro-premixing reaction unit during the period, so that the premixing operation of four different molar ratio formulas can be completed in parallel in one set of equipment and one continuous production cycle, not only greatly improving the equipment utilization and production efficiency, but also giving the production line strong flexible output capacity, which can quickly respond to the production demand of the market for different purity grades and characteristics of trifluoroacetamide products, and improves the overall production efficiency of trifluoroacetamide;

[0026] 2、The three high-pressure steel pipes in the application respectively convey three kinds of raw materials, wherein the damping pipe is specially arranged on the ethyl trifluoroacetate pipeline, which can effectively smooth the pulse generated by the metering pump, ensure the stable flow, the pressure valve table installed on the anhydrous ammonia pipeline can monitor the pipeline pressure in real time, and the pressure relief pipe arranged on the converging horizontal pipe provides an emergency pressure relief channel for the system. The above design structure jointly guarantees the smoothness and safety of the feeding process. Meanwhile, the premixing inner cavity is designed as a circle and placed in a square box, forming a buffer space which provides a safety margin for the expansion of the inner cavity in abnormal conditions. The center shaft and the partition plate can maintain sealing under dynamic rotation, effectively preventing cross contamination of materials between the sub-chambers, ensuring that the raw materials of the four ratio schemes can be accurately and independently conveyed and premixed, and building a safe operating environment, reducing the risk in the production process to a controllable range;

[0027] 3、The application provides a high-efficiency parallel experiment platform, which enables technicians to set four candidate formulations at a time, uses the intermittent rotation mechanism of the equipment to make the four candidate formulations perform premixing simultaneously under the same macroscopic working conditions, and directly compares and analyzes the four products with different purities generated by the four candidate formulations, so that the optimal process parameters can be quickly and accurately screened out. The above production mode changes the traditional serial trial-and-error process into parallel comparison and optimization, greatly shortens the period from laboratory research and development to industrialized large-scale production, provides a powerful technical tool for continuous improvement of the trifluoroacetamide production process and development of new formulations, and has remarkable scientific research and application value. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the application, the drawings needed in the description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0029] Figure 1 It is a schematic diagram of the overall structure of the production equipment of the application;

[0030] Figure 2 It is a schematic diagram of the premixing box structure of the application;

[0031] Figure 3 It is a schematic diagram of the partition plate mounting structure of the application;

[0032] Figure 4 It is a schematic diagram of the feeding mechanism detailed structure of the application;

[0033] Figure 5 It is a schematic diagram of the center shaft mounting structure of the application;

[0034] Figure 6This is a schematic diagram of the power drive shaft mounting structure of the present invention;

[0035] Figure 7 This is a detailed structural diagram of the drive mechanism of the present invention;

[0036] Figure 8 This is a schematic diagram of the cam disk structure of the present invention;

[0037] In the diagram: 1. Platform, 2. Premixing chamber, 3. Feeding mechanism, 301. Manifold horizontal pipe, 302. First flow vertical pipe, 303. Second flow vertical pipe, 304. Pipe coil, 305. Damping pipe, 306. First high-pressure steel pipe, 307. Second high-pressure steel pipe, 308. Third high-pressure steel pipe, 309. First port, 310. Second port, 311. Pressure relief pipe, 312. Pressure valve gauge, 4. Premixing cavity, 5. Central shaft, 6. Baffle plate, 7. Distributing cavity, 8. Shaft collar seat. 9. Power drive shaft, 10. Drive mechanism, 1001. Cam plate, 1002. Groove, 1003. Cross bracket, 1004. Cylindrical, 1005. Heart-shaped protrusion, 1006. Through slot, 1007. Beveled surface, 11. Bearing seal ring, 12. Support seat, 13. Rotary wheel base, 14. Rotary wheel, 15. Support ring, 16. First bearing seat, 17. Second bearing seat, 18. Vertical plate, 19. Three-phase asynchronous motor, 20. Unloading box, 21. Third flow vertical pipe. Detailed Implementation

[0038] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0039] This specific embodiment provides a production equipment for trifluoroacetamide, such as... Figures 1-8 As shown, it includes a platform 1, which is composed of two layers of beams with a gap in between. A premixing box 2 is fixedly installed on the platform 1. The premixing box 2 has a square structure and a circular inner cavity inside, which is the premixing inner cavity 4. The space between the premixing inner cavity 4 and the outer shell of the premixing box 2 is a buffer structure, which can provide a safe buffer space for the expansion of the premixing inner cavity 4.

[0040] The top of the premix box 2 is provided with a feeding mechanism 3. The feeding mechanism 3 comprises a flow collecting cross pipe 301 arranged above the premix box 2, the bottom of the flow collecting cross pipe 301 is fixedly installed with a first flow circulating vertical pipe 302 and a second flow circulating vertical pipe 303, the bottom ends of the first flow circulating vertical pipe 302 and the second flow circulating vertical pipe 303 are communicated with the premix inner cavity 4 after penetrating through the shell of the premix box 2. One end of the flow collecting cross pipe 301 is fixedly installed with a pipe disc 304, the pipe disc 304 is installed with a damping pipe 305, a first high-pressure steel pipe 306 and a second high-pressure steel pipe 307, the damping pipe 305 is arranged at the center of the pipe disc 304, and the first high-pressure steel pipe 306 and the second high-pressure steel pipe 307 are arranged at the edge of the pipe disc 304. The damping pipe 305 is connected with a third high-pressure steel pipe 308, the inlet of the third high-pressure steel pipe 308 is connected with an ethyl trifluoroacetate conveying device, and the ethyl trifluoroacetate can be conveyed into the premix inner cavity 4 through the third high-pressure steel pipe 308 and the damping pipe 305; the first high-pressure steel pipe 306 and the second high-pressure steel pipe 307 are respectively communicated with the conveying devices of anhydrous liquid ammonia and tetrahydrofuran, so that the first high-pressure steel pipe 306 and the second high-pressure steel pipe 307 respectively convey anhydrous liquid ammonia and tetrahydrofuran into the premix inner cavity 4.

[0041] The end of the flow collecting cross pipe 301 away from the pipe disc 304 is provided with a first port 309 and a second port 310, the direction of the first port 309 is the same as the pipe diameter direction of the flow collecting cross pipe 301, and the first port 309 and the second port 310 are arranged in a port radial direction. The first port 309 and the second port 310 can provide multiple temporary docking ports for the flow collecting cross pipe 301, so as to facilitate the temporary addition of other production raw materials in the production of trifluoroacetamide. The pipeline of the first high-pressure steel pipe 306 is installed with a pressure valve table 312, so as to facilitate the real-time monitoring of the flow pressure in the first high-pressure steel pipe 306, and ensure that the internal pressure of the flow collecting cross pipe 301 is within a safe range. The side of the first port 309 is provided with a pressure relief pipe 311 fixedly installed on the pipe wall of the flow collecting cross pipe 301; the pressure relief pipe 311 can provide an operation structure for the emergency pressure relief of the flow collecting cross pipe 301.

[0042] The premixing box 2 is provided with a circular through hole on both sides for the center shaft 5 to pass through, and the outer side of the two circular through holes is provided with a bearing sealing ring 11 which is sleeved on the outer periphery of the center shaft 5, thereby ensuring the airtightness of the premixing box 2 and forming a dynamic sealing fitting structure between the center shaft 5 and the premixing box 2. The premixing box 2 is provided with a support seat 12 fixedly connected to the gantry 1 on both sides, and the two support seats 12 are symmetrically arranged and each is fixedly provided with a runner base 13, and two runner wheels 14 are rotatably arranged on each runner base 13, and each runner wheel 14 is arranged below and parallel to the center shaft 5. The outer wall of the center shaft 5 is fixedly sleeved with a support ring 15, and the outer wall of the runner wheel 14 is provided with a trapezoidal groove matching the width dimension of the support ring 15, so that the outer wall of each runner wheel 14 is in sliding fit with the outer wall of the support ring 15, thereby providing effective support structure for the rotation of the runner wheel 14.

[0043] The left side of the premixing box 2 is provided with a shaft ring seat 8 fixedly connected to the gantry 1, and the left end of the center shaft 5 is arranged in the interior of the shaft ring seat 8 and is in rotary fit with the shaft ring seat 8, so as to provide support structure for the rotation of the center shaft 5. The right side of the gantry 1 is fixedly provided with a first bearing seat 16 and a second bearing seat 17 on the top, the first bearing seat 16 is fixedly provided with a vertical plate 18, the right end of the center shaft 5 is fixedly connected with a power driven shaft 9, and the outer wall of the power driven shaft 9 is in rotary fit with the top end of the vertical plate 18, so as to provide support structure for the rotation of the power driven shaft 9. The second bearing seat 17 is fixedly provided with a three-phase asynchronous motor 19, and the output end of the three-phase asynchronous motor 19 is in transmission fit with the power driven shaft 9 through a driving mechanism 10.

[0044] The driving mechanism 10 includes a cam disc 1001, which is a circular structure. The disc surface on one side of the cam disc 1001 is connected with the output end of the three-phase asynchronous motor 19 through a shaft coupling, and the disc surface on the other side of the cam disc 1001 is provided with a heart-shaped cam 1005, and the periphery of the heart-shaped cam 1005 is provided with a groove 1002, which is a heart-shaped annular groove structure. The cross bracket 1003 is fixedly installed on the end of the power driving shaft 9 close to the three-phase asynchronous motor 19, and the outer sides of the upper, lower, left and right four ends of the cross bracket 1003 are fixedly installed with cylinders 1004, and the four cylinders 1004 are arranged in parallel with the power driving shaft 9. The two sides of the groove 1002 are provided with symmetrically arranged through slots 1006, the opening size of the through slots 1006 is matched with the diameter size of the cylinders 1004, and the side portions of the two through slots 1006 are provided with inclined surfaces 1007 arranged on the cam disc 1001, which can be slidably connected with the outer walls of the cylinders 1004; when the outer walls of two of the cylinders 1004 are slidably connected with the inner walls of the groove 1002, the other two cylinders 1004 are arranged on the outer side of the cam disc 1001, when one of the cylinders 1004 slides out of the cam disc 1001 through one of the through slots 1006, the adjacent cylinder 1004 (except the cylinder 1004 in the groove 1002) slides into the groove 1002 through the other through slot 1006; when the cam disc 1001 rotates, the power driving shaft 9 is driven to rotate intermittently by 90° under the transmission of the cross bracket 1003, and a part of intermittent time can be left after each rotation by 90°.

[0045] The outer wall of the central shaft 5 is fixedly installed with four equidistantly arranged partition plates 6, the outer edges of the partition plates 6 are slidably connected with the inner cavity wall of the premixing inner cavity 4, and the dynamic sealing structure is formed by arranging an oil film on the inner wall of the premixing inner cavity 4. The four equidistantly arranged partition plates 6 divide the premixing inner cavity 4 into four equal-volume distribution cavities 7, so that the four distribution cavities 7 receive the ethyl trifluoroacetate, anhydrous liquid ammonia and tetrahydrofuran delivered from the feeding mechanism 3. The bottom of the premixing box 2 is fixedly installed with a discharge box 20, the top end of the discharge box 20 is provided with an automatic door and is connected with the premixing inner cavity 4; the discharge box 20 is in a funnel structure, the bottom end of the discharge box 20 is arranged in the inner part of the rack 1 and is fixedly connected with a third flow-through vertical pipe 21; by controlling the opening and closing of the automatic door, the flow of the premixing raw materials flowing out of the distribution cavities 7 is controlled, so as to control the overall equipment flow.

[0046] The above describes an embodiment of a trifluoroacetamide production equipment, and based on the trifluoroacetamide production equipment described in the above embodiment, the embodiment of the present application further provides a trifluoroacetamide production method corresponding to the equipment, which includes the following steps:

[0047] S1: Delivering ethyl trifluoroacetate into one of the four sub-chambers 7 in the premixing cavity 4 through the third high-pressure steel pipe 308, and stabilizing the ethyl trifluoroacetate flow through the damping pipe 305, so that it is in a continuous and stable delivery environment. Delivering anhydrous liquid ammonia and tetrahydrofuran into the above-mentioned sub-chambers 7 through the first high-pressure steel pipe 306 and the second high-pressure steel pipe 307 respectively, and monitoring the pressure inside the pipeline in real time through the pressure valve table 312. The molar ratios of ethyl trifluoroacetate, anhydrous liquid ammonia, and tetrahydrofuran in the four sub-chambers 7 are all different.

[0048] Among them, the four molar ratio schemes of trifluoroacetamide in the four sub-chambers 7 are:

[0049] Scheme one: ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.0:4.5;

[0050] Scheme two: ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.2:2.3;

[0051] Scheme three: ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.6:9.2;

[0052] Scheme four: ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:0.8:4.5.

[0053] S2: Continuously rotating the cam plate 1001 at a uniform speed by driving it with the three-phase asynchronous motor 19, so that two of the cylinders 1004 slide in the grooves 1002. One of the cylinders 1004 can slide out of the groove 1002 through the through slot 1006, so that the central shaft 5 rotates intermittently. After each rotation of 90°, each sub-chamber 7 stays under the feeding mechanism 3 for a predetermined time, which can be controlled between 15s-20s. After multiple intermittent rotations of the central shaft 5, the delivery of ethyl trifluoroacetate, anhydrous liquid ammonia, and tetrahydrofuran is completed. The partition plate 6 can ensure the independence of each chamber and prevent cross-contamination.

[0054] S3: During the intermittent rotation of the central shaft 5, the ethyl trifluoroacetate, anhydrous liquid ammonia and tetrahydrofuran are pre-mixed into four kinds of molar ratio of trifluoroacetamide in the four distribution cavities 7; the purity of the expected product of trifluoroacetamide produced by scheme one is 97%-98%, containing a small amount of unreacted ethyl trifluoroacetate impurities, which can be used for pesticide synthesis, general chemical intermediates, and belongs to medium value products; the purity of the expected product of trifluoroacetamide produced by scheme two is greater than 99.5%, which is high in purity, stable in quality, and white crystalline powder, which can be used for pesticide, pharmaceutical intermediates, material science, and belongs to high value products; the purity of the expected product of trifluoroacetamide produced by scheme three is greater than 99.9%, which has the characteristics of ultra-high purity, and the impurity content is extremely low, which can be used for high-end medicine, electronic chemicals, analytical reagents, and belongs to extremely high value products; the purity of the expected product of trifluoroacetamide produced by scheme four is less than 95%, which is poor in purity and contains a large amount of impurities, which can be used for recycling products, and belongs to secondary utilization additional products; the four kinds of molar ratio of trifluoroacetamide in the four distribution cavities 7 are discharged through the discharge box 20 and the third flow-through vertical pipe 21.

[0055] If you want to enter the high value-added medicine and material market, you must choose a process that can stably produce products with a purity of ≥99.5%, and scheme two can be used; if you pursue the extreme electronic chemical market, scheme three process is needed; if you consider the low-end market, scheme one process is used; if you need to provide reactants for secondary recycling, scheme four process can be used.

[0056] The above description of disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A production apparatus for trifluoroacetamide, comprising a frame (1), characterized in that, A premixing chamber (2) is fixedly installed on the frame (1). A feeding mechanism (3) is provided on the top of the premixing chamber (2). A premixing cavity (4) is provided inside the premixing chamber (2). The feeding mechanism (3) is used to feed ethyl trifluoroacetate, anhydrous liquid ammonia, and tetrahydrofuran into the premixing cavity (4). A rotatable central shaft (5) is provided inside the premixing cavity (4). Four equally spaced partition plates (6) are fixedly installed on the outer wall of the central shaft (5). The outer edge of the partition plates (6) slides against the inner wall of the premixing cavity (4). The four equally spaced partition plates (6) will... The premixed inner cavity (4) is divided into four equal-volume dispensing cavities (7); the outer side of the premixed box (2) is provided with a collar seat (8) that is fastened to the frame (1), one end of the central shaft (5) is arranged inside the collar seat (8) and rotates with it, the other end of the central shaft (5) is fixedly connected to a power drive shaft (9), and a drive mechanism (10) is installed at the outer end of the power drive shaft (9). The drive mechanism (10) is used to make the power drive shaft (9) rotate intermittently by 90°. After the central shaft (5) rotates 90°, one of the dispensing cavities (7) is connected to the feeding mechanism (3); The feeding mechanism (3) includes a manifold (301), and a first flow vertical pipe (302) and a second flow vertical pipe (303) are fixedly installed at the bottom of the manifold (301). The bottom ends of the first flow vertical pipe (302) and the second flow vertical pipe (303) are connected to the premixing cavity (4). A pipe disc (304) is fixedly installed at one end of the manifold (301). A damping pipe (305), a first high-pressure steel pipe (306), and a second high-pressure steel pipe (307) are installed on the pipe disc (304). The damping pipe (305) is connected to a third high-pressure steel pipe (308). The third high-pressure steel pipe (308) is used to transport ethyl trifluoroacetate. The first high-pressure steel pipe (306) and the second high-pressure steel pipe (307) are used to transport anhydrous liquid ammonia and tetrahydrofuran, respectively. A first bearing seat (16) and a second bearing seat (17) are fixedly installed on the platform (1). A vertical plate (18) is fixedly installed on the first bearing seat (16). The outer wall of the power drive shaft (9) is rotatably engaged with the top of the vertical plate (18). A three-phase asynchronous motor (19) is fixedly installed on the second bearing seat (17). The output end of the three-phase asynchronous motor (19) is driven by the drive mechanism (10). The drive mechanism (10) includes a cam disk (1001). 01) One side of the disk is connected to the output end of the three-phase asynchronous motor (19). A groove (1002) is provided on one side of the cam disk (1001). A cross bracket (1003) is fixedly installed at the end of the power drive shaft (9). A cylinder (1004) is fixedly installed on the outer side of the four ends of the cross bracket (1003). When the outer walls of two cylinders (1004) slide with the inner wall of the groove (1002), the other two cylinders (1004) are arranged on the outer side of the cam disk (1001).

2. The trifluoroacetamide production equipment according to claim 1, characterized in that, The manifold (301) has a first port (309) and a second port (310) at the end away from the pipe coil (304). The first port (309) and the second port (310) are arranged radially perpendicularly. A pressure relief pipe (311) is fixedly installed on the pipe wall of the manifold (301) at the side of the first port (309). A pressure valve (312) is installed on the pipeline of the first high-pressure steel pipe (306).

3. The trifluoroacetamide production equipment according to claim 1, characterized in that, The premix box (2) is equipped with bearing seals (11) on both sides. The bearing seals (11) are fitted around the central shaft (5). The premix box (2) is provided with support seats (12) that are fastened to the frame (1) on both sides. Rotary wheel bases (13) are fixedly installed on the two support seats (12). Two rotating wheels (14) are rotatably installed on each rotating wheel base (13). A support ring (15) is fixedly fitted on the outer wall of the central shaft (5). The outer wall of the rotating wheel (14) slides with the outer wall of the support ring (15).

4. The trifluoroacetamide production equipment according to claim 1, characterized in that, The cam disk (1001) has a heart-shaped protrusion (1005) on the side of the disk near the cross bracket (1003). The groove (1002) is arranged on the outside of the heart-shaped protrusion (1005). The groove (1002) is a heart-shaped annular groove structure. Symmetrically arranged through slots (1006) are opened on both outer edges of the groove (1002). The opening size of the through slots (1006) is adapted to the diameter of the cylinder (1004). The sides of the two through slots (1006) are provided with inclined surfaces (1007) arranged on the cam disk (1001). The inclined surfaces (1007) can slide with the outer wall of the cylinder (1004).

5. The trifluoroacetamide production equipment according to claim 1, characterized in that, The bottom of the premix box (2) is fixedly installed with a discharge box (20). The top of the discharge box (20) is connected to the premix inner cavity (4). The discharge box (20) has a funnel-shaped structure. The bottom of the discharge box (20) is arranged inside the frame (1) and is tightly connected to a third flow vertical pipe (21).

6. A method for producing trifluoroacetamide, comprising the trifluoroacetamide production equipment according to any one of claims 1-5, characterized in that, The method includes: S1: Ethyl trifluoroacetate is delivered to one of the distribution chambers (7) in the premixed inner cavity (4) through the third high-pressure steel pipe (308), and the flow rate of ethyl trifluoroacetate is stabilized through the damping pipe (305). Anhydrous liquid ammonia and tetrahydrofuran are delivered to the above distribution chambers (7) through the first high-pressure steel pipe (306) and the second high-pressure steel pipe (307) respectively. The flow rates of ethyl trifluoroacetate, anhydrous liquid ammonia, and the molar ratio of tetrahydrofuran in the four distribution chambers (7) are all different. S2: The cam disk (1001) is driven by a three-phase asynchronous motor (19) to rotate continuously at a constant speed, so that two cylinders (1004) slide in the groove (1002). The cylinders (1004) can slide out of the groove (1002) through the through slot (1006), so that the central shaft (5) rotates intermittently. After each rotation of 90°, each material distribution chamber (7) stays below the feeding mechanism (3) for a predetermined time to complete the conveying of ethyl trifluoroacetate, anhydrous liquid ammonia, and tetrahydrofuran. The partition plate (6) can ensure that the materials in each chamber are independent and prevent cross-contamination. S3: During the intermittent rotation of the central shaft (5), ethyl trifluoroacetate, anhydrous liquid ammonia, and tetrahydrofuran are premixed in four distribution chambers (7) to form four molar ratios of trifluoroacetamide. The four molar ratios of trifluoroacetamide in the four distribution chambers (7) are discharged through the unloading box (20) and the third flow vertical pipe (21).

7. The method for producing trifluoroacetamide according to claim 6, characterized in that, The four trifluoroacetamide molar ratio schemes in the four dispensing chambers (7) are as follows: Option 1: Ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.0:4.5; Option 2: Ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.2:2.3; Option 3: Ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:1.6:9.2; Option 4: Ethyl trifluoroacetate: anhydrous liquid ammonia: tetrahydrofuran = 1:0.8:4.5.

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