Continuous reaction device for 3-acetylmercapto-2-methyl propionic acid

Abstract

A continuous reaction device for 3-acetylmercapto-2-methyl propionic acid comprises a reactor, a separator, a distillation tower, a raw material dropwise adding tank and a raw material storage tank, the reactor is a dynamic tubular reactor, a first feed inlet and a second feed inlet are formed in the top of one end of the reactor and connected with the raw material dropwise adding tank and the raw material storage tank respectively, and the separator is connected with the distillation tower. The top of the other end of the reactor is provided with a first exhaust port and is connected with a raw material storage tank through a first condenser, the bottom of the other end of the reactor is provided with a first discharge port, the separator is a dynamic tubular reactor, and the top of one end of the separator is provided with a third feed port and is connected with the first discharge port of the reactor; a second exhaust port is formed in the top of the other end of the separator and connected with a feeding port of the distillation tower, a second discharging port is formed in the bottom of the other end of the separator, and a tower top exhaust port of the distillation tower is connected with a receiving tank through a second condenser. The reaction kettle is simple in structure and convenient to operate, and can achieve the purpose of continuous production on the basis of improving the reaction efficiency.

Description

Technical Field

[0001] The utility model relates to the field of chemical industry, in particular to a continuous reaction device for 3-acetylmercapto-2-methylpropionic acid. Background Art

[0002] 3-Acetylmercapto-2-methylpropionic acid is an important fine organic chemical intermediate, widely used in the fields of medicine, pesticides, chemical industry, etc., mainly used as a pharmaceutical intermediate.

[0003] At present, 3-acetylmercapto-2-methylpropionic acid is mostly synthesized by thioacetic acid method, with thioacetic acid and methacrylic acid as raw materials, and reacted in a closed reactor (such as patent No.: CN105037231A, CN102864203A, etc.). The reaction is an exothermic reaction, which causes the temperature in the reactor to rise faster, easily causing unreacted methacrylic acid to self-polymerize, resulting in a reduction in conversion rate. At the same time, after the reaction is completed, the reaction product needs to be transferred to a still to carry out the next stage process, and the production efficiency is low.

[0004] Therefore, how to design a device that can realize continuous synthesis of 3-acetylmercapto-2-methylpropionic acid is a problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] The utility model aims to provide a 3-acetylmercapto-2-methylpropionic acid continuous reaction device in view of the deficiencies in the prior art. The device has a simple structure and is easy to operate. On the basis of improving the reaction efficiency, the purpose of continuous production can be achieved.

[0006] The technical scheme of the utility model is: a 3-acetylmercapto-2-methylpropionic acid continuous reaction device, comprising a reactor, a separator, a distillation tower, a raw material dropping tank, and a raw material storage tank. The reactor is a dynamic tubular reactor, a first feed port and a second feed port are arranged on the top of one end of the reactor, and are respectively connected with the raw material dropping tank and the raw material storage tank, a first exhaust port is arranged on the top of the other end of the reactor, and is connected with the raw material storage tank via a first condenser, a first discharge port is arranged at the bottom of the other end of the reactor, the separator is a dynamic tubular reactor, a third feed port is arranged on the top of one end of the separator, and is connected with the first discharge port of the reactor, a second exhaust port is arranged on the top of the other end of the separator, and is connected with the feed port of the distillation tower, a second discharge port is arranged at the bottom of the other end of the separator, and the tower top exhaust port of the distillation tower is connected with a receiving tank via a second condenser.

[0007] The tops of the reactor and separator are both provided with temperature sensors and pressure sensors.

[0008] A flow meter is also provided between the raw material dropping tank and the first feed inlet.

[0009] The raw material dripping tank, the raw material storage tank and the receiving tank are all provided with liquid level gauges.

[0010] The distillation tower is a packed tower.

[0011] The above technical solution has the following beneficial effects:

[0012] The continuous reaction device of 3-acetylmercapto-2-methylpropionic acid comprises a reactor, a separator, a distillation tower, a raw material dropping tank, and a raw material storage tank, wherein the reactor is used as a reaction place for synthesizing the target product, and the separator cooperates with the distillation tower to form a distillation system for separating the target product and unreacted raw materials. The reactor is a dynamic tubular reactor, and a first feed port and a second feed port are arranged on the top of one end of the reactor, which are respectively connected to the raw material dropping tank and the raw material storage tank, and the thioacetic acid of one of the raw materials is sent into the reactor through the raw material storage tank and the second feed port, and the methacrylic acid of the second raw material is dripped into the reactor through the raw material dropping tank and the first feed port, so as to ensure that the methacrylic acid dripped and the thioacetic acid in the reactor are fully contacted and reacted, and the occurrence of the self-polymerization reaction of methacrylic acid is reduced, and the dripping speed can be determined according to the reaction situation, and the temperature control energy consumption is reduced. A first exhaust port is arranged on the top of the other end of the reactor, which is connected to the raw material storage tank through the first condenser, and part of the unreacted thioacetic acid in the reactor is discharged from the reactor in the form of gas phase, and is collected in the raw material storage tank for recycling after being condensed into a liquid state. The first discharge port is arranged at the bottom of the other end of the reactor, and the separator is a dynamic tubular reactor. The third feed port is arranged at the top of one end of the separator, which is connected to the first discharge port of the reactor. The remaining unreacted raw materials (mainly thioacetic acid) and the target product 3-acetylmercapto-2-methylpropionic acid enter the separator through the first discharge port and the third feed port. The second exhaust port is arranged at the top of the other end of the separator, which is connected to the feed port of the distillation tower. The second discharge port is arranged at the bottom of the other end of the separator. The mixed material in the separator is further heated, wherein the unreacted raw material thioacetic acid and a small amount of target product are converted into gas phase, enter the rectifying tower through the second exhaust port, and the target product is intercepted by the rectifying tower. The top exhaust port of the distillation tower is connected to a receiving tank through the second condenser, and the separated unreacted raw materials are sent to the receiving tank for collection and recycling after liquefaction, so that the raw material utilization rate is effectively improved. Using the dynamic tubular reactor as a reactor and a separator, continuous feeding and discharging can also be achieved to realize continuous production of 3-acetylmercapto-2-methylpropionic acid.

[0013] Further description is given below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model.

[0015] In the accompanying drawings, 1 is a reactor, 11 is a first feed port, 12 is a second feed port, 13 is a first exhaust port, 14 is a first discharge port, 2 is a separator, 21 is a third feed port, 22 is a second exhaust port, 23 is a second discharge port, 3 is a distillation tower, 4 is a raw material dropping tank, 5 is a raw material storage tank, 6 is a first condenser, 7 is a second condenser, and 8 is a receiving tank. DETAILED DESCRIPTION

[0016] See also Figure 1 , is a specific embodiment of a continuous reaction device for 3-acetylmercapto-2-methylpropionic acid. The continuous reaction device for 3-acetylmercapto-2-methylpropionic acid comprises a reactor 1, a separator 2, a distillation tower 3, a raw material dropping tank 4, and a raw material storage tank 5. The reactor 1 is a dynamic tubular reactor. Obviously, the dynamic tubular reactor is provided with a heat exchange interlayer, and steam is used as a heat exchange medium. A first feed port 11 and a second feed port 12 are provided at the top of one end of the reactor 1, which are connected to the raw material dropping tank 4 and the raw material storage tank 5 respectively. Obviously, the first feed port and the second feed port correspond to the starting end of the agitator of the dynamic tubular reactor, and the first feed port and the second feed port are both provided with valves to control opening and closing. Further, in order to facilitate the observation of the dripping flow rate, a flow meter is also provided between the raw material dropping tank 4 and the first feed port 11. In order to facilitate the observation of the liquid level of the raw material dropping tank and the raw material storage tank, a liquid level meter is provided on the raw material dropping tank and the raw material storage tank. A first exhaust port 13 is arranged at the top of the other end of the reactor 1, which is connected to the raw material storage tank 5 through the first condenser 6. A first discharge port 14 is arranged at the bottom of the other end of the reactor 1, that is, the first exhaust port and the first discharge port correspond to the terminal end of the dynamic tubular reactor agitator, and the first exhaust port and the first discharge port are both provided with valves to control opening and closing. The separator 2 is a dynamic tubular reactor. Obviously, the dynamic tubular reactor is provided with a heat exchange interlayer, and steam is used as a heat exchange medium. A third feed port 21 is arranged at the top of one end of the separator 2, which is connected to the first discharge port 14 of the reactor 1. Specifically, the separator is arranged below the reactor, and the third feed port corresponds to the starting end of the dynamic tubular reactor agitator, and the third feed port is provided with a valve to control opening and closing. A second exhaust port 22 is arranged at the top of the other end of the separator 2, which is connected to the feed port of the distillation tower 3. A second discharge port 23 is arranged at the bottom of the other end of the separator 2, that is, the second exhaust port and the second discharge port correspond to the terminal end of the dynamic tubular reactor agitator, and the second exhaust port and the second discharge port are both provided with valves to control opening and closing. The top exhaust port of the distillation tower 3 is connected to a receiving tank 8 via a second condenser 7. Specifically, the distillation tower is a packed tower, and a liquid level gauge is provided on the receiving tank.

[0017] Furthermore, in order to detect the states of the reactor 1 and the separator 2, temperature sensors and pressure sensors are provided on the tops of the reactor and the separator.

[0018] The working principle of the utility model is as follows: the stirrers of the reactor and the separator are turned on, and the reactor and the separator are heated through the corresponding heat exchange interlayer. Thioacetic acid, one of the raw materials, is continuously added to the reactor through the raw material storage tank, and methacrylic acid, the second raw material, is continuously dripped into the reactor through the raw material dripping tank, and the mixed reaction generates the target product. The reaction material is transferred to the right end of the reactor by the stirrer, wherein the unreacted part of the thioacetic acid is gasified, and is returned to the raw material storage tank through the first exhaust port and the first condenser for recycling, and part of the thioacetic acid and the target product enter the separator through the first discharge port and the third feed port, and after further heating, the unreacted thioacetic acid and a small amount of the target product are gasified, and enter the distillation tower through the second exhaust port, wherein the gaseous thioacetic acid is condensed into liquid through the second condenser, and then sent to the receiving tank for recycling, and the target product is continuously discharged through the second discharge port.

Claims

1. A 3-acetylmercapto-2-methylpropionic acid continuous reaction device, characterized in that: It comprises a reactor (1), a separator (2), a distillation tower (3), a raw material dropping tank (4), and a raw material storage tank (5). The reactor (1) is a dynamic tubular reactor. A first feed port (11) and a second feed port (12) are arranged at the top of one end of the reactor (1), which are connected to the raw material dropping tank (4) and the raw material storage tank (5) respectively. A first exhaust port (13) is arranged at the top of the other end of the reactor (1), which is connected to the raw material storage tank (5) via a first condenser (6). A first discharge port (14) is arranged at the bottom of the other end of the reactor (1). The separator (2) is a dynamic tubular reactor. A third feed port (21) is provided at the top of one end of the separator (2) and is connected to the first discharge port (14) of the reactor (1). A second exhaust port (22) is provided at the top of the other end of the separator (2) and is connected to the feed port of the distillation tower (3). A second discharge port (23) is provided at the bottom of the other end of the separator (2). The top exhaust port of the distillation tower (3) is connected to a receiving tank (8) via a second condenser (7).

2. The 3-acetylmercapto-2-methylpropionic acid continuous reaction device according to claim 1, characterized in that: The tops of the reactor (1) and the separator (2) are both provided with temperature sensors and pressure sensors.

3. The 3-acetylmercapto-2-methylpropionic acid continuous reaction device according to claim 1, characterized in that: A flow meter is also provided between the raw material dropping tank (4) and the first feed port (11).

4. The 3-acetylmercapto-2-methylpropionic acid continuous reaction device according to claim 1, characterized in that: The raw material dropping tank (4), the raw material storage tank (5) and the receiving tank (8) are all provided with liquid level gauges.

5. The 3-acetylmercapto-2-methylpropionic acid continuous reaction device according to claim 1, characterized in that: The distillation tower (3) is a packed tower.

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