Sodium 2-hydroxy-benzonitrile solution production device

Abstract

The utility model discloses a sodium 2-hydroxy-benzonitrile solution production device which comprises a raw material dehydration system, a reaction system, a neutralization layering system and a cooling crystallization salifying system which are connected in sequence, the cooling crystallization salifying system comprises a crystallization kettle, a stirring structure is arranged in the crystallization kettle, a methylbenzene adding pipeline and a methylbenzene suction pipe are arranged on the crystallization kettle, and the methylbenzene suction pipe is connected with the reaction system. The bottom end of the methylbenzene suction pipe can extend to the position above crystals in the crystallization kettle, a material outlet pipeline and a sodium hydroxide solution adding pipeline are arranged on the crystallization kettle, the material outlet pipeline is connected with the preparation tank, a discharging pipeline is arranged at the bottom of the preparation tank, and a valve is arranged on the discharging pipeline. The sodium hydroxide solution is directly added into the finished product of 2-hydroxy-benzonitrile in the crystallization kettle and does not need to be taken out, exposure of 2-hydroxy-benzonitrile in front of production personnel is reduced, the sodium hydroxide solution of 2-hydroxy-benzonitrile sodium is directly prepared in the step, feeding is facilitated for downstream customers, and physical and psychological health of personnel can be greatly protected. And material drying is not needed, and energy consumption of drying is reduced.

Description

Technical Field

[0001] The utility model relates to a device for producing sodium salicylonitrile solution, belonging to the field of chemical production. Background Art

[0002] Salicylonitrile, also known as o-hydroxybenzonitrile, is a chemical substance with the chemical formula C7H5NO. It is one of the important intermediates for synthesizing the fungicide azoxystrobin. Its synthesis mainly has the following two methods:

[0003] 1. Salicylaldehyde reacts with hydroxylamine hydrochloride to form salicylaldoxime, and then salicylonitrile is obtained by dehydration with acetic anhydride or thionyl chloride.

[0004] 2. Salicylamide is dehydrated in the presence of phosgene, thionyl chloride or phosphorus trioxide to obtain salicylonitrile.

[0005] Salicylonitrile has a highly irritating odor. Even a small amount can affect people's breathing, and the smell is bitter. The produced salicylonitrile finished product will not only cause great physical harm to production personnel, but also pose great problems during transportation. When downstream manufacturers continue to produce using salicylonitrile, there are also odor problems during feeding, causing great harm to the body. Therefore, we hope to directly convert salicylonitrile into an aqueous solution of sodium salicylonitrile. On the one hand, it is convenient for downstream manufacturers to feed materials (when using salicylonitrile to produce downstream products, usually an aqueous sodium hydroxide solution needs to be added), and the materials can be directly sucked. On the other hand, it reduces the exposure of personnel to salicylonitrile and reduces personnel injuries. Summary of the Utility Model

[0006] Aiming at the above technical problems, the purpose of the utility model is to provide a device for producing sodium salicylonitrile solution, which can directly produce a sodium salt solution without taking out salicylonitrile, avoiding the exposure of salicylonitrile, reducing personnel injuries, and facilitating the direct feeding of downstream products.

[0007] To achieve the above purpose, the technical solution of the utility model is: a device for producing sodium salicylonitrile solution, including a raw material dehydration system, a reaction system, and a neutralization and stratification system connected in sequence. It is characterized in that: it further includes a cooling and crystallization and salting system. The cooling and crystallization and salting system includes a crystallization kettle. A stirring structure is arranged inside the crystallization kettle. A toluene adding pipeline and a toluene suction pipe are arranged on the crystallization kettle. The bottom end of the toluene suction pipe can extend above the crystals in the crystallization kettle. A material outlet pipeline and a sodium hydroxide solution adding pipeline are arranged on the crystallization kettle. The material discharging pipeline is connected to a modulation tank. An outlet pipeline is arranged at the bottom of the modulation tank. A valve is arranged on the outlet pipeline.

[0008] In the above solution: the toluene suction pipe is connected to the buffer storage tank, a vacuum pipe is provided on the buffer storage tank, and a valve is provided on the toluene suction pipe. The toluene sucked out is collected by the buffer tank and can be recycled.

[0009] In the above solution: the toluene addition pipeline is connected to the toluene storage tank, and a metering pump and a valve are provided on the toluene addition pipeline. The toluene is added quantitatively by the metering pump to achieve automated production.

[0010] In the above solution: the sodium hydroxide solution addition pipeline is connected to the sodium hydroxide solution storage tank, and a metering pump is provided on the sodium hydroxide solution addition pipeline. The pre-prepared sodium hydroxide is added quantitatively by the metering pump.

[0011] In the above solution: a nitrogen pressurization pipeline is provided on the crystallization kettle. The sodium salicylaldimine sodium hydroxide solution in the crystallization kettle is directly pressed into the conditioning tank by nitrogen. In the conditioning tank, the concentration and content are measured, and if necessary, a part of sodium hydroxide is added to reach the concentration required by the customer.

[0012] Beneficial effects: In the cooling step of the present utility model, the toluene in the crystallization kettle is directly evacuated by vacuum, and then toluene is replenished and the crystallization kettle is washed again. The replenishment of toluene for washing can be done once or twice. The sodium salicylaldimine finished product directly adds the sodium hydroxide solution in the crystallization kettle without taking it out, reducing the exposure of sodium salicylaldimine in front of production personnel. The sodium hydroxide solution of sodium salicylaldimine is directly prepared in this step, without odor, which is convenient for downstream customers to feed materials, and can greatly protect the physical and mental health of personnel. Moreover, there is no need for material drying, reducing the energy consumption of drying. Description of the Drawings

[0013] Figure 1 is a schematic structural diagram of the present utility model. Detailed Embodiments

[0014] The present utility model will be further described below through embodiments in conjunction with the drawings:

[0015] Embodiment 1, as Figure 1 shown, a sodium salicylaldimine solution production device includes a raw material dehydration system, a reaction system, a neutralization and stratification system, and a cooling and crystallization and salting system connected in sequence.

[0016] The raw material dehydration system, the reaction system, and the neutralization and stratification system are prior arts.

[0017] Among them, the raw material dehydration system includes a dehydration kettle 1, in which a stirring device is arranged. At its top, there is a salicylamide addition port and a toluene addition pipeline. The toluene addition pipeline is connected to a toluene storage tank 7. A pump 8, a flow meter 9 and an automatic control valve 10 are arranged on the toluene addition pipeline. Toluene is pumped into the dehydration kettle 1 by the pump, reducing personnel contact. A steam outlet is arranged at the upper end of the dehydration kettle 1 and is connected to a condenser 11. Toluene and salicylamide are refluxed and dehydrated in the dehydration kettle. After the water turns into steam, it is condensed and separated by the condenser 11.

[0018] The reaction system includes a photochemical reaction kettle 2. The bottom discharge port of the dehydration kettle 1 is connected to the material inlet of the photochemical reaction kettle 2 through a pipeline, and a valve is arranged on this pipeline. A phosgene addition pipeline and a tail gas pipeline are arranged at the top of the photochemical reaction kettle 2. The phosgene addition pipeline extends to the bottom inside of the photochemical reaction kettle 2 and is connected to a phosgene buffer tank 18. A flow meter and an automatic control valve are arranged on the phosgene addition pipeline. The tail gas pipeline is connected to a tail gas buffer tank 12. A tail gas recovery pipeline is arranged on the tail gas buffer tank 12 and is connected to the inside of the photochemical reaction kettle 2. A tail gas pipeline is also arranged on the tail gas buffer tank 12 and is connected to a tail gas destruction system. The tail gas destruction system includes a hydrogen chloride absorption device 13, a water destruction tower 14 and an alkali destruction tower 15 connected in sequence. The alkali destruction tower 15 is connected to an exhaust system, and an ammonia injection nozzle is arranged in the exhaust system to perform ammonia injection treatment on the passing tail gas. Automatic control valves are arranged on both the tail gas recovery pipeline and the tail gas pipeline.

[0019] The neutralization and stratification system includes a washing kettle 3. The bottom discharge port of the photochemical reaction kettle 2 is connected to the feed inlet of the washing kettle 3 through a feed pipe. A pH meter and a temperature sensor are arranged in the washing kettle 3. A first washing liquid addition pipeline and a second washing liquid addition pipeline are arranged at the top of the washing kettle 3. The first washing liquid addition pipeline and the second washing liquid addition pipeline are respectively connected to a first washing liquid storage tank 16 and a second washing liquid storage tank 17. Pumps, flow meters and automatic control valves are respectively arranged on the first washing liquid addition pipeline and the second washing liquid addition pipeline. The bottom drain pipe of the washing kettle 3 is connected to a waste water storage tank 20. The bottom organic phase pipeline of the washing kettle 3 is connected to the liquid inlet of a crystallization kettle 4. Pressure nitrogen pipelines are arranged at the tops of the dehydration kettle 1, the photochemical reaction kettle 2 and the washing kettle 3. Heating jackets are arranged outside the dehydration kettle 1, the photochemical reaction kettle 2 and the washing kettle 3. Regarding the heating jackets and the stirring structures, they are all conventional designs and are not drawn in the figure.

[0020] The cooling and crystallization salt-forming system comprises a crystallization kettle 4, and a heating jacket is arranged outside the crystallization kettle 4. A stirring structure is arranged in the crystallization kettle 4, and a toluene adding pipeline and a toluene suction pipe 5 are arranged on the top of the crystallization kettle 4. The bottom of the toluene suction pipe 5 can extend to the top of the crystal in the crystallization kettle (according to the crystalline solid material in the crystallization kettle 4, the depth of the extension is adjusted, and the top of the crystal is extended as far as possible). The crystallization kettle 4 is provided with a material outlet pipeline and a sodium hydroxide solution adding pipeline. The material discharging pipeline is connected to the modulation tank 6, and the bottom of the modulation tank 6 is provided with a discharging pipeline. The discharging pipeline of the modulation tank 6 is provided with a valve. Since the material is not centrifuged, toluene is sucked by vacuum, and residual toluene is always present in the material. In the modulation tank 6, a small amount of toluene will float (layered) on the upper surface of the aqueous solution, so our material is released from the bottom, so that the layered toluene can be removed. At the same time, in the modulation tank, the concentration of sodium salicylonitrile can also be fine-tuned by adding sodium hydroxide, etc., to meet the concentration requirements of customers.

[0021] The toluene suction pipe 5 is connected to the buffer storage tank 19, and the toluene suction pipe 5 extends to the bottom of the buffer tank 19. The buffer storage tank 19 is provided with a vacuum tube 1901, and a valve is provided on the toluene suction pipe.

[0022] The toluene adding pipeline is connected to the toluene storage tank 21, and a metering pump 22 and a valve are arranged on the toluene adding pipeline.

[0023] The sodium hydroxide solution adding pipeline is connected to the sodium hydroxide solution storage tank 23, and a metering pump 22 is arranged on the sodium hydroxide solution adding pipeline.

[0024] A nitrogen pressurizing pipeline is provided on the top of the crystallization kettle, through which the material can be pressed out.

[0025] The present utility model is not limited to the above-mentioned embodiments. The raw material dehydration system, reaction system and neutralization stratification system are not limited to the structure in Embodiment 1. A person skilled in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and purpose of the present utility model. The scope of the present utility model is defined by the claims and their equivalents.

Claims

1. A sodium salicylonitrile solution production device, comprising a raw material dehydration system, a reaction system, and a neutralization and stratification system connected in sequence, characterized in that: It further includes a cooling crystallization and salting system, and the cooling crystallization and salting system includes a crystallization kettle, a stirring structure is arranged in the crystallization kettle, a toluene addition pipeline and a toluene suction pipe are arranged on the crystallization kettle, the bottom end of the toluene suction pipe can extend above the crystals in the crystallization kettle, a material outlet pipeline and a sodium hydroxide solution addition pipeline are arranged on the crystallization kettle, the material outlet pipeline is connected to a modulation tank, a discharge pipeline is arranged at the bottom of the modulation tank, and a valve is arranged on the discharge pipeline.

2. The sodium salicylonitrile solution production device according to claim 1, wherein: The toluene suction pipe is connected to a buffer storage tank, a vacuum pipe is arranged on the buffer storage tank, and a valve is arranged on the toluene suction pipe.

3. The sodium salicylonitrile solution production device according to claim 2, characterized in that: The toluene addition pipeline is connected to a toluene storage tank, and a metering pump and a valve are arranged on the toluene addition pipeline.

4. The production device of sodium salicylonitrile solution according to any one of claims 1-3, characterized in that: The sodium hydroxide solution addition pipeline is connected to a sodium hydroxide solution storage tank, and a metering pump is arranged on the sodium hydroxide solution addition pipeline.

5. The sodium salicylonitrile solution production device according to claim 4, characterized in that: A nitrogen pressurization pipeline is arranged on the crystallization kettle.

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