Tubular reaction device applied to continuous flow chlorination synthesis of 2-chloronicotinonitrile

Abstract

The utility model relates to a tubular reaction device applied to continuous flow chlorination synthesis of 2-chloronicotinonitrile, which comprises a plurality of horizontal longitudinal reaction joint pipes, and the reaction joint pipes are linearly, transversely and uniformly distributed and placed on a front group of transverse bottom beams and a rear group of transverse bottom beams; a transverse pressing beam is pressed on the reaction section pipe right above the transverse bottom beam; two ends of the transverse pressing beam are fixedly connected with two ends of the transverse bottom beam through bolts respectively; the reaction section pipes on the left side of the transverse bottom beam are connected together through a connecting pipe and form a continuous S-shaped tubular reactor with the connecting pipe, a vertical feeding connecting pipe is formed in the middle of each reaction section pipe, a transverse main feeding pipe is arranged above the front portion of each feeding connecting pipe, and the right end of each main feeding pipe is fixedly connected with a sealing head. And a plurality of branch pipes opposite to the reaction joint pipes are formed on the main feeding pipe. The tubular reaction device is a tubular reactor similar to a modular structure and can be conveniently spliced to form the continuous flow reactor, and a feeding structure with corresponding flow control is arranged in each section of reaction tube, so that high-efficiency reaction synthesis of products can be realized.

Description

Technical Field

[0001] This utility model relates to the technical field of porcelain drying racks, and more specifically to a tubular reaction apparatus used in the continuous flow chlorination synthesis of 2-chloronicotinamide. Background Technology

[0002] 2-Chloronicotinonitrile is a key intermediate for 2-chloronicotinic acid, an important fine chemical intermediate used in the synthesis of many medical analgesics or anti-inflammatory agents, antibiotics, cardiovascular drugs, and agricultural fungicides, insecticides, and herbicides. For example, it is used to synthesize the nonsteroidal anti-inflammatory drug niflufenicol, the antidepressant mirtazapine, the anti-HIV drug nevirapine, and the herbicides nicosulfuron and pyrifluquinazon. 2-Chloronicotinonitrile is obtained from N-oxo-3-cyanopyridine and phosphorus oxychloride through a reaction. To achieve efficient reaction synthesis and continuous production, it can be carried out in a continuous flow reactor. The main reaction pipeline can be supplied with a solution of N-oxo-3-cyanopyridine, and phosphorus oxychloride can be introduced into the main reaction pipeline through the feed pipe to initiate the reaction. To achieve a continuous flow reaction, the flow rate of the feed materials needs to be controlled, thus requiring the design of a continuous flow reactor that meets the above requirements. Utility Model Content

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a tubular reaction apparatus for the continuous flow chlorination synthesis of 2-chloronicotinamide. This tubular reaction apparatus is a modular tubular reactor, which can be easily assembled into the continuous flow reactor. At the same time, each section of the reaction tube is equipped with a feed structure with corresponding flow control, which can achieve efficient reaction synthesis of the product.

[0004] A tubular reactor for the continuous flow chlorination synthesis of 2-chloronicotinamide includes several horizontally longitudinal reaction sections, which are linearly and evenly distributed and rest on two sets of horizontal bottom beams. A horizontal pressure beam is held on the reaction sections directly above the horizontal bottom beams, and the two ends of the horizontal pressure beam are fixed to the two ends of the horizontal bottom beams by bolts. The reaction sections on the left side of the horizontal bottom beams are connected together by semi-circular connecting pipes and form a continuous S-shaped tubular reactor. A vertical feed pipe is formed in the middle of the reaction section, and a horizontal main feed pipe is provided above the front of the feed pipe. A head is fixed to the right end of the main feed pipe, and several branch pipes are formed on the main feed pipe that are directly opposite the reaction sections.

[0005] A second bend is fixed to the feed inlet pipe at the far right of the tubular reactor. The end of the second bend is fixed to the outlet of the electromagnetic shut-off valve. The inlet of the electromagnetic shut-off valve is fixed to a branch pipe on the main feed pipe. A first bend is fixed to the feed inlet pipe of the reaction section pipe to the left of the second bend. The end of the first bend is fixed to the outlet of the flow control valve. The inlet of the flow control valve is fixed to a branch pipe to the left of the second bend. A cap is fixed to the branch pipe to the right of the second bend.

[0006] Preferably, a number of transversely distributed longitudinal support beams are fixedly connected to the transverse pressure beam, and the longitudinal support beams are arranged between the reaction section pipes; the main feed pipe rests on the longitudinal support beams and is fitted with pipe clamps, and the two ends of the pipe clamps are fixed to the longitudinal support beams by bolts.

[0007] Preferably, the number of reaction tubes in the tubular reactor is even, and the total number of reaction tubes on the bottom beam is also even.

[0008] The number of branch pipes on the main feed pipe is equal to the number of reaction section pipes.

[0009] Preferably, flanges are formed at both ends of the reaction tube, both ends of the connecting tube, the end of the feed tube, both ends of the main feed tube, the end of the branch tube, both ends of the first bend and both ends of the second bend.

[0010] Preferably, the length of the reaction tube is greater than the length of the connecting tube, and the branch tubes are located directly above the reaction tube and are linearly and evenly distributed on the main feed tube.

[0011] Preferably, the end cap is screwed to a transverse central screw, the left end of the central screw is inserted into the main feed pipe and fixed with a circular sealing block, the sealing block is located on the right side of the second bend, and a handwheel is fixed to the right end of the central screw.

[0012] Preferably, the sealing block includes a circular piston block, the outer ring of which is formed with an annular groove, and a piston ring is inserted and fixed in the annular groove, the piston ring pressing against the inner wall of the main feed pipe.

[0013] The beneficial effects of this utility model are as follows:

[0014] 1. The tubular reaction device is a tubular reactor with a modular structure, which can be easily assembled into the continuous flow reactor. At the same time, each section of the reaction tube is equipped with a corresponding flow control feeding structure, which can realize the efficient reaction synthesis of the product.

[0015] 2. Its tubular reaction device is also designed with a corresponding cleaning structure to facilitate the cleaning of the tubular reaction device. Attached Figure Description

[0016] Figure 1This is a three-dimensional structural diagram of the present invention;

[0017] Figure 2 for Figure 2 A magnified schematic diagram of the structure at point A in the middle.

[0018] In the diagram: 1. Reaction section pipe; 11. Feed pipe; 2. Horizontal bottom beam; 3. Horizontal pressure beam; 4. Longitudinal support beam; 5. Connecting pipe; 6. Main feed pipe; 61. Branch pipe; 7. First bend pipe; 8. Flow control valve; 9. Second bend pipe; 10. Solenoid shut-off valve; 20. End cap; 30. Cover; 40. Central screw; 50. Handwheel; 60. Sealing block; 601. Piston block; 602. Piston ring; 70. Pipe clamp. Detailed Implementation

[0019] Example: See Figure 1 , 2 As shown, a tubular reactor used for the continuous flow chlorination synthesis of 2-chloronicotinamide includes several horizontally longitudinal reaction sections 1. The reaction sections 1 are linearly and evenly distributed laterally and rest on two sets of horizontal bottom beams 2. A horizontal pressure beam 3 is held on the reaction sections 1 directly above the horizontal bottom beams 2. The two ends of the horizontal pressure beam 3 are fixed to the two ends of the horizontal bottom beams 2 by bolts. The reaction sections 1 on the left side of the horizontal bottom beams 2 are connected together by a semi-circular connecting pipe 5 and form a continuous S-shaped tubular reactor with the connecting pipe 5. A vertical feed pipe 11 is formed in the middle of the reaction section 1. A horizontal main feed pipe 6 is provided above the front of the feed pipe 11. A head 20 is fixed to the right end of the main feed pipe 6. Several branch pipes 61 are formed on the main feed pipe 6, which are directly opposite to the reaction sections 1.

[0020] A second bend 9 is fixedly connected to the feed inlet pipe 11 at the far right end of the tubular reactor. The end of the second bend 9 is fixedly connected to the outlet of the electromagnetic shut-off valve 10. The inlet of the electromagnetic shut-off valve 10 is fixedly connected to the branch pipe 61 on the main feed pipe 6. A first bend 7 is fixedly connected to the feed inlet pipe 11 of the reaction section pipe 1 on the left side of the second bend 9. The end of the first bend 7 is fixedly connected to the outlet of the flow control valve 8. The inlet of the flow control valve 8 is fixedly connected to the branch pipe 61 on the left side of the second bend 9. A cap 30 is fixedly fixed to the branch pipe 61 on the right side of the second bend 9.

[0021] Several transversely distributed longitudinal support beams 4 are fixedly connected to the transverse pressure beam 3, and the longitudinal support beams 4 are arranged between the reaction section pipes 1; the main feed pipe 6 rests on the longitudinal support beams 4 and is fitted with pipe clamps 70, and the two ends of the pipe clamps 70 are fixed to the longitudinal support beams 4 by bolts, making the installation and connection of the main feed pipe 6 convenient.

[0022] The number of reaction tubes 1 in the tubular reactor is even, and the number of all reaction tubes 1 on the bottom beam 2 is even; thus, the feed pipe 11 on the last set of reaction tubes 1 is connected to the electromagnetic shut-off valve 10, which is used as a manifold for cleaning.

[0023] The number of branch pipes 61 on the main feed pipe 6 is equal to the number of reaction pipes 1.

[0024] Flanges are formed at both ends of the reaction section pipe 1, both ends of the connecting pipe 5, the end of the feed pipe 11, both ends of the main feed pipe 6, the end of the branch pipe 61, both ends of the first bend pipe 7, and both ends of the second bend pipe 9. The flanges are installed by bolt assemblies, which facilitates the composition of the tubular reaction device.

[0025] The length of the reaction tube 1 is greater than the length of the connecting tube 5. The branch tube 61 is located directly above the reaction tube 1 and is linearly and evenly distributed on the main feed tube 6. The position of the branch tube 61 facilitates the installation and connection of the second bend 9, the first bend 7, the flow control valve 8 and the solenoid shut-off valve 10.

[0026] The end cap 20 is screwed to a transverse central screw 40. The left end of the central screw 40 is inserted into the main feed pipe 6 and a circular sealing block 60 is fixedly connected thereto. The sealing block 60 is located on the right side of the second bend pipe 9. A handwheel 50 is fixedly connected to the right end of the central screw 40. The central screw 40 is rotated by the handwheel 50 to adjust the position of the sealing block 60, thereby preventing the raw material of the main feed pipe 6 from entering the part of the main feed pipe 6 on the right side of the second bend pipe 9. Therefore, the inner wall of that part of the main feed pipe 6 does not need to be cleaned.

[0027] The sealing block 60 includes a circular piston block 601. The outer ring of the piston block 601 is formed with an annular groove, and a piston ring 602 is inserted and fixed in the annular groove. The piston ring 602 presses against the inner wall of the main feed pipe 6.

[0028] Working principle: This structure is a tubular reaction device for the continuous flow chlorination synthesis of 2-chloronicotinamide. The basic structure of the tubular reaction device consists of multiple sets of reaction section tubes 1. The required length of the reaction device can be freely selected after being connected by connecting tubes 5.

[0029] Meanwhile, each group of reaction tubes 1 is equipped with a feed pipe 11, which can be connected to the main feed pipe 6 for transporting phosphorus oxychloride. The feed pipe 11 at the front is equipped with a corresponding flow control valve 8, which can control the amount of phosphorus oxychloride entering the tubular reaction device to achieve its efficient reaction synthesis.

[0030] Meanwhile, although the last set of reaction pipes 1 of the tubular reactor is connected to the main feed pipe 6, an electromagnetic shut-off valve 10 is installed between them, and the reactor is isolated from the main feed pipe 6 during the reaction. The last set of reaction pipes 1 provides sufficient reaction time for the feed of the previous set of reaction pipes 1, and also serves as a manifold component for cleaning.

[0031] During cleaning, clean water is introduced into the inlet of the first set of reaction tubes 1, and the electromagnetic shut-off valve 10 on the last set of reaction tubes 1 is opened, and clean water is also introduced into its main feed pipe 6. Finally, all water is discharged from the outlet of the last set of reaction tubes 1, making cleaning convenient.

[0032] The embodiments described herein are illustrative and not intended to limit the scope of the invention. Any person skilled in the art can modify the embodiments without departing from the spirit and scope of the invention; therefore, the scope of protection of the invention should be as set forth in the claims.

Claims

1. A tubular reactor for continuous flow chlorination synthesis of 2-chloronicotinamide, comprising several horizontally longitudinal reaction sections (1), the reaction sections (1) being linearly and uniformly distributed laterally and resting on two sets of horizontal bottom beams (2); a horizontal pressure beam (3) is pressed on the reaction sections (1) directly above the horizontal bottom beams (2), and the two ends of the horizontal pressure beam (3) are respectively fixed to the two ends of the horizontal bottom beams (2) by bolts; the reaction sections (1) on the left side of the horizontal bottom beams (2) are connected together by semi-circular connecting pipes (5) and form a continuous S-shaped tubular reactor with the connecting pipes (5), characterized in that: A vertical feed pipe (11) is formed in the middle of the reaction tube (1). A horizontal main feed pipe (6) is provided above the front of the feed pipe (11). A cap (20) is fixed to the right end of the main feed pipe (6). Several branch pipes (61) are formed on the main feed pipe (6) that are directly opposite to the reaction tube (1). A second bend (9) is fixed to the feed inlet pipe (11) at the far right end of the tubular reactor. The end of the second bend (9) is fixed to the outlet of the electromagnetic shut-off valve (10). The inlet of the electromagnetic shut-off valve (10) and the branch pipe (61) on the main feed pipe (6) are fixed together. A first bend (7) is fixed to the feed inlet pipe (11) of the reaction section pipe (1) on the left side of the second bend (9). The end of the first bend (7) is fixed to the outlet of the flow control valve (8). The inlet of the flow control valve (8) is fixed to the branch pipe (61) on the left side of the second bend (9). A cap (30) is fixed to the branch pipe (61) on the right side of the second bend (9).

2. The tubular reactor device for the continuous flow chloro- synthesis of 2-chloronicotinonitrile according to claim 1, characterized in that: Several transversely distributed longitudinal support beams (4) are fixedly connected to the transverse pressure beam (3), and the longitudinal support beams (4) are set between the reaction section pipes (1); the main feed pipe (6) rests on the longitudinal support beam (4) and is fitted with a pipe clamp (70), and the two ends of the pipe clamp (70) are fixed to the longitudinal support beam (4) by bolts.

3. The tubular reactor device for the continuous flow chloro- synthesis of 2-chloronicotinonitrile according to claim 1, characterized in that: The number of reaction tubes (1) inside the tubular reactor is even, and the number of all reaction tubes (1) on the bottom beam (2) is even; The number of branch pipes (61) on the main feed pipe (6) is equal to the number of reaction section pipes (1).

4. The tubular reactor device for the continuous flow chloro- synthesis of 2-chloronicotinonitrile according to claim 1, characterized in that: Flanges are formed at both ends of the reaction pipe (1), both ends of the connecting pipe (5), the end of the feed pipe (11), both ends of the main feed pipe (6), the end of the branch pipe (61), both ends of the first bend (7), and both ends of the second bend (9).

5. The tubular reactor device for the continuous flow chloro- synthesis of 2-chloronicotinonitrile according to claim 1, characterized in that: The length of the reaction tube (1) is greater than the length of the connecting tube (5), and the branch tube (61) is located directly above the reaction tube (1) and is linearly and evenly distributed on the main feed tube (6).

6. The tubular reactor device for the continuous flow chloro- synthesis of 2-chloronicotinonitrile according to claim 1, characterized in that: The end cap (20) is screwed to a transverse central screw (40). The left end of the central screw (40) is inserted into the main feed pipe (6) and fixed with a circular sealing block (60). The sealing block (60) is located on the right side of the second bend pipe (9). The right end of the central screw (40) is fixed with a handwheel (50).

7. The tubular reactor device for the continuous flow chloro- synthesis of 2-chloronicotinonitrile according to claim 6, characterized in that: The sealing block (60) includes a circular piston block (601), the outer ring of the piston block (601) is formed with an annular groove, and a piston ring (602) is inserted and fixed in the annular groove. The piston ring (602) presses against the inner wall of the main feed pipe (6).

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