A continuous reaction device for 1-methylpyridine chloride

Abstract

The utility model discloses a 1-methylpyridine chloride continuous reaction device, belongs to the technical field of organic synthesis devices, including chloromethane tank, the outlet of chloromethane tank is connected to the inlet of buffer tank, the outlet of buffer tank is connected to the inlet of vaporizer, the outlet of vaporizer is connected to the gas phase inlet of tubular reactor by regulating valve, the liquid phase inlet of tubular reactor is connected to the outlet of plunger pump, the inlet of plunger pump is connected to the outlet of mixing device, the gas phase outlet of tubular reactor is connected to the inlet of back pressure valve, and the outlet of back pressure valve is connected to the gas phase inlet of condensing pot. The utility model can solve the problem of uneven mixing of gas and liquid in reactor, so that reaction yield is low, and the reaction does not mention the problem of tail gas treatment. The utility model can solve the problem of reaction tail gas pollution and waste of resources, realizes the continuous and high-yield synthesis of 1-methylpyridine chloride, and the reaction time is reduced by 50%, which has important guiding significance for industrial production.

Description

Technical Field

[0001] The utility model relates to the technical field of organic synthesis devices, in particular to a 1-methylpyridine chloride continuous reaction device. Background Art

[0002] 1-Methylpyridinium chloride, also known as methylpyridinium chloride in Chinese, has a molecular formula of C6H8ClN and a molecular weight of 129.59. It is an important pesticide and pharmaceutical intermediate. The domestic industrial production method of 1-methylpyridinium chloride mostly uses pyridine as raw material, methyl chloride gas phase feed, methanol, ethanol or water as solvent, and heats for 10-30 hours at 50-80°C to obtain a 1-methylpyridinium chloride solution, and then evaporates and recovers the solvent, and dries to obtain a 1-methylpyridinium chloride solid. The reaction adopts intermittent autoclave synthesis, which has the problems of long reaction time and low production efficiency.

[0003] The Chinese patent with publication number CN115403513A discloses a continuous synthesis process of N-methylpyridine chloride, wherein a mixture of pyridine and methanol is preheated and reacted with methyl chloride gas in a tubular reactor under heat and pressure, thereby realizing continuous production of N-methylpyridine chloride; however, the patent has the following defects:

[0004] The gas-liquid mixing in the reactor is uneven, resulting in a low reaction yield, and the reaction does not mention tail gas treatment. Utility Model Content

[0005] The utility model aims to provide a 1-methylpyridine chloride continuous reaction device, which can solve the problems of reaction tail gas pollution and resource waste, realize the continuous and high-yield synthesis of 1-methylpyridine chloride, reduce the reaction time by 50%, have important guiding significance for industrial production, and solve the problems in the prior art.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A methylpyridine chloride continuous reaction device comprises a methyl chloride tank, wherein the outlet of the methyl chloride tank is connected to the inlet of a buffer tank, the outlet of the buffer tank is connected to the inlet of a vaporizer, the outlet of the vaporizer is connected to the gas phase inlet of a tubular reactor through a regulating valve, the liquid phase inlet of the tubular reactor is connected to the outlet of a plunger pump, the inlet of the plunger pump is connected to the outlet of a mixing device, the gas phase outlet of the tubular reactor is connected to the inlet of a back pressure valve, the outlet of the back pressure valve is connected to the gas phase inlet of a condensing tank, the gas phase outlet of the condensing tank is connected to the inlet of a booster pump, the outlet of the booster pump is connected to the inlet of the methyl chloride tank, and the liquid phase outlet of the tubular reactor is connected to the inlet of a crystallization evaporator.

[0008] Preferably, the pressure in the tubular reactor is controlled by a regulating valve and a back pressure valve.

[0009] Preferably, the pressure in the tubular reactor is less than 1 MPa, and the regulating valve is opened; the pressure in the tubular reactor is greater than 1.2 MPa, and the back pressure valve is opened to release the pressure.

[0010] Preferably, the inlet and outlet of the tubular reactor are filled with fillers, and the material of the fillers is stainless steel.

[0011] Preferably, the reaction tail gas separated from the condenser is compressed by a booster pump and then recycled.

[0012] Preferably, a coil is installed in the condensing tank.

[0013] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0014] The inlet and outlet of the tubular reactor of the utility model are both filled with fillers, which can ensure that the gas-liquid contact fully reacts, can reduce the entrainment of synthetic liquid in the outlet gas phase of the tubular reactor, and the fillers at the inlet and outlet can be conveniently disassembled and washed. The tail gas at the gas phase outlet of the tubular reactor is purified by a condenser, and then enters a booster pump for compression and pressurization, and can be returned to the methyl chloride tank for recycling, which can solve the problems of reaction tail gas pollution and resource waste, realize the continuous and high-yield synthesis of 1-methylpyridine chloride, and reduce the reaction time by 50%, which has important guiding significance for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The utility model is a structural principle diagram of the 1-methylpyridinium chloride continuous reaction device.

[0016] In the figure: 1. Methyl chloride tank; 2. Buffer tank; 3. Vaporizer; 4. Regulating valve; 5. Mixing device; 6. Plunger pump; 7. Tubular reactor; 8. Packing; 9. Back pressure valve; 10. Condensation tank; 11. Coil; 12. Booster pump; 13. Crystallization evaporator. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] In order to solve the technical problems of uneven gas-liquid mixing in the existing reactor, resulting in low reaction yield and no tail gas treatment, please refer to Figure 1, this embodiment provides the following technical solutions:

[0019] A 1-methylpyridinium chloride continuous reaction device comprises a chloromethane tank 1, the outlet of the chloromethane tank 1 is connected to the inlet of a buffer tank 2, the outlet of the buffer tank 2 is connected to the inlet of a vaporizer 3, the outlet of the vaporizer 3 is connected to the gas phase inlet of a tubular reactor 7 through a regulating valve 4, the liquid phase inlet of the tubular reactor 7 is connected to the outlet of a plunger pump 6, and the inlet of the plunger pump 6 is connected to the outlet of a mixing device 5.

[0020] The mixing device 5 is used to mix pyridine and methanol.

[0021] The inlet and outlet of the tubular reactor 7 are both filled with fillers 8, and the material of the fillers 8 is stainless steel.

[0022] It should be noted that the inlet and outlet of the tubular reactor 7 are filled with fillers 8, which can ensure sufficient gas-liquid contact reaction and reduce the entrainment of synthetic liquid in the outlet gas phase of the tubular reactor 7. In addition, the fillers 8 at the inlet and outlet can be easily disassembled and cleaned.

[0023] The gas phase outlet of the tubular reactor 7 is connected to the inlet of the back pressure valve 9, the outlet of the back pressure valve 9 is connected to the gas phase inlet of the condensing tank 10, a coil 11 is installed in the condensing tank 10, the gas phase outlet of the condensing tank 10 is connected to the inlet of the booster pump 12, the outlet of the booster pump 12 is connected to the inlet of the chloroform tank 1, and the liquid phase outlet of the tubular reactor 7 is connected to the inlet of the crystallization evaporator 13.

[0024] The synthetic liquid discharged from the liquid phase outlet of the tubular reactor 7 enters the crystallization evaporator 13 for evaporation and crystallization. The crystallization evaporator 13 can be a normal pressure evaporation or a reduced pressure evaporation.

[0025] In this embodiment, the pressure inside the tubular reactor 7 is controlled by the regulating valve 4 and the back pressure valve 9, wherein, when the pressure inside the tubular reactor 7 is less than 1 MPa, the regulating valve 4 is opened, and when the pressure inside the tubular reactor 7 is greater than 1.2 MPa, the back pressure valve 9 is opened to release the pressure.

[0026] In this embodiment, the reaction tail gas separated from the condensation tank 10 is compressed by the booster pump 12 and then recycled.

[0027] Specifically, the gas phase condensed in the condensation tank 10 is pressurized by the booster pump 12 and then pumped into the methyl chloride tank 1 for recycling.

[0028] Specifically, the bottom valve of the chloromethane tank 1 is opened, and the chloromethane enters the buffer tank 2. The chloromethane is vaporized by the vaporizer 3 and enters the tubular reactor 7 through the regulating valve 4. The mixed liquid of pyridine and methanol is transported to the tubular reactor 7 through the plunger pump 6. The outlet gas phase of the tubular reactor 7 enters the condensation tank 10 through the back pressure valve 9. The gas phase condensed in the condensation tank 10 is pressurized by the booster pump 12 and then pumped into the chloromethane tank 1. The synthetic liquid discharged from the liquid phase outlet of the tubular reactor 7 directly enters the crystallization evaporator 13 for concentration and purification, so as to obtain a 1-methylpyridine chloride solid with a content of more than 99%. The 1-methylpyridine chloride can be synthesized continuously with high yield, and the resource utilization of the reaction tail gas can be realized.

[0029] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0030] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A 1-methylpyridinium chloride continuous reaction device, comprising a methyl chloride tank (1), characterized in that: The outlet of the methyl chloride tank (1) is connected to the inlet of the buffer tank (2), the outlet of the buffer tank (2) is connected to the inlet of the vaporizer (3), the outlet of the vaporizer (3) is connected to the gas phase inlet of the tubular reactor (7) through the regulating valve (4), the liquid phase inlet of the tubular reactor (7) is connected to the outlet of the plunger pump (6), the inlet of the plunger pump (6) is connected to the outlet of the mixing device (5), the gas phase outlet of the tubular reactor (7) is connected to the inlet of the back pressure valve (9), the outlet of the back pressure valve (9) is connected to the gas phase inlet of the condensation tank (10), the gas phase outlet of the condensation tank (10) is connected to the inlet of the booster pump (12), the outlet of the booster pump (12) is connected to the inlet of the methyl chloride tank (1), and the liquid phase outlet of the tubular reactor (7) is connected to the inlet of the crystallization evaporator (13).

2. A 1-methylpyridinium chloride continuous reaction device according to claim 1, characterized in that: The pressure in the tubular reactor (7) is controlled by a regulating valve (4) and a back pressure valve (9).

3. A 1-methylpyridinium chloride continuous reaction device according to claim 1, characterized in that: When the pressure in the tubular reactor (7) is less than 1 MPa, the regulating valve (4) is opened; when the pressure in the tubular reactor (7) is greater than 1.2 MPa, the back pressure valve (9) is opened to release the pressure.

4. A 1-methylpyridinium chloride continuous reaction device according to claim 1, characterized in that: The inlet and outlet of the tubular reactor (7) are both filled with fillers (8), and the material of the fillers (8) is stainless steel.

5. A 1-methylpyridinium chloride continuous reaction device according to claim 1, characterized in that: The reaction tail gas separated from the condensation tank (10) is compressed by a booster pump (12) and then recycled.

6. A 1-methylpyridinium chloride continuous reaction device according to claim 1, characterized in that: A coil (11) is installed in the condensation tank (10).

Images