Continuous reactor of o-chlorobenzyl chloride

Abstract

The utility model relates to the technical field of an o-chlorobenzyl chloride reactor, in particular to an o-chlorobenzyl chloride continuous reactor which comprises a mixing tank for mixing a liquid reactant and a catalyst, a reaction tower which is communicated with the mixing tank through a pipeline and is used for providing a reaction place for the liquid reactant and a gas reactant, and a communicated heat exchanger of the reaction tower, the heat exchanger is communicated with the gas-liquid separation tank, the reaction tower is communicated with a receiving tank for receiving reaction products, a rotatable stirring paddle is arranged in the mixing tank, a flow guide pump is arranged on a pipeline between the mixing tank and the reaction tower, and reflux pipelines are arranged among the heat exchanger, the gas-liquid separation tank and the reaction tower. Therefore, chlorine and chlorotoluene can be heated, mixed and continuously fed and discharged, the conversion rate of reaction is improved, side reaction products are reduced, and the reaction yield is ensured.

Description

Technical Field

[0001] This utility model relates to the field of o-chlorobenzyl chloride reactor technology, and in particular to a continuous o-chlorobenzyl chloride reactor. Background Technology

[0002] o-chlorobenzyl chloride is an important organic synthesis intermediate widely used in the pharmaceutical, pesticide, and dye industries. Using o-chlorobenzyl chloride as a raw material, a series of high-value intermediates or products can be synthesized, such as the anti-inflammatory and analgesic drug diclofenac sodium, enzyme inhibitor, o-chlorophenylacetonitrile, as well as the insecticides paclobutrazol, cypermethrin, and the highly effective herbicide methomyl.

[0003] Currently, most manufacturers of o-chlorobenzyl chloride use a chlorination distillation synthesis process, using o-chlorotoluene and chlorine as raw materials. The process involves catalytic chlorination to synthesize o-chlorobenzyl chloride. The chlorinated liquid is then washed with alkali and distilled under reduced pressure to obtain o-chlorobenzyl chloride. O-chlorobenzyl chloride is often produced using a single-reactor batch process. This batch reaction method results in low conversion rates, high raw material consumption, difficulty in guaranteeing product quality, and ineffective control of side reactions. When the conversion rate exceeds 40%, the dichlorobenzyl content in the chlorinated liquid is significantly high. To ensure the reaction yield, the o-chlorotoluene conversion rate can only be controlled at around 40%, leading to the need for most of the o-chlorotoluene to be refined and recovered from the chlorinated liquid and chlorinated again. This results in high raw material and energy consumption, and makes it difficult to guarantee product quality.

[0004] How to heat and mix chlorine and chlorotoluene for continuous feeding and discharging, thereby improving the reaction conversion rate, reducing the generation of by-products, and ensuring the reaction yield, has become a technical problem that needs to be solved.

[0005] In conclusion, the existing technology obviously has inconveniences and defects in practical use, so it is necessary to improve it. Utility Model Content

[0006] To address the aforementioned deficiencies, the present invention aims to provide a continuous reactor for o-chlorobenzyl chloride, which can continuously feed and discharge chlorine gas and chlorotoluene by heating and mixing them, thereby improving the reaction conversion rate, reducing the generation of by-products, and ensuring the reaction yield.

[0007] To achieve the above objectives, this invention provides a continuous reactor for o-chlorobenzyl chloride, comprising a mixing tank for mixing liquid reactants with a catalyst, the mixing tank being connected via a pipeline to a reaction tower for providing a reaction site for the liquid and gaseous reactants.

[0008] The reaction tower is connected to a heat exchanger, the heat exchanger is connected to a gas-liquid separator, and the reaction tower is connected to a receiving tank for receiving reaction products.

[0009] According to the continuous reactor for o-chlorobenzyl chloride of this invention, a flow guide pump is provided on the pipeline between the mixing tank and the reaction tower.

[0010] According to the present invention, in a continuous reactor for o-chlorobenzyl chloride, the mixing tank is equipped with a rotatable stirring paddle.

[0011] According to the continuous reactor for o-chlorobenzyl chloride of this utility model, a reflux pipe is provided between the heat exchanger, the gas-liquid separator and the reaction tower.

[0012] According to the continuous reactor of o-chlorobenzyl chloride of this invention, the liquid separated by the gas-liquid separator is returned to the reaction tower through the reflux pipe between the gas-liquid separator and the reaction tower.

[0013] According to the continuous reactor for o-chlorobenzyl chloride of the present invention, the reaction tower includes an upper tower section, an intermediate tower section and a lower tower section, and the outer walls of the intermediate tower section and the lower tower section are provided with jackets, and the lower tower section is provided with a light source incident device.

[0014] According to the continuous reactor for o-chlorobenzyl chloride of this utility model, a buffer tank is provided between the mixing tank and the reaction tower. The buffer tank temporarily stores the liquid mixed in the mixing tank and then introduces it into the reaction tower. A distributor is provided in the reaction tower to divert the introduced liquid.

[0015] According to the continuous reactor of o-chlorobenzyl chloride of this utility model, the receiving tank is connected to a heat exchanger, and a reflux pipe is provided between the heat exchanger and the receiving tank. The gas separated by the heat exchanger is discharged after merging with the gas separated by the gas-liquid separator through the pipe, and the liquid separated by the heat exchanger at the receiving tank is returned to the receiving tank through the reflux pipe.

[0016] The purpose of this invention is to provide a continuous reactor for the reaction of o-chlorobenzyl chloride, comprising a mixing tank and a reaction tower, capable of continuously feeding and discharging chlorine gas and chlorotoluene through heating and mixing, ensuring product quality and improving reaction conversion rate. The combination of the mixing tank and the reaction tower effectively reduces the generation of by-products, ensuring reaction yield. The combination of a heat exchanger and a gas-liquid separator recovers the generated hydrogen chloride gas, saving production costs. In summary, the beneficial effects of this invention are: continuous feeding and discharging of chlorine gas and chlorotoluene through heating and mixing, improving reaction conversion rate, reducing by-products, and ensuring reaction yield. Attached Figure Description

[0017] Figure 1 This is a flowchart of the present invention;

[0018] In the diagram: 1-mixing tank, 2-diversion pump, 3-reaction tower, 4-heat exchanger, 5-gas-liquid separator, 6-receiving tank, 7-buffer tank. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the scope of the present utility model.

[0020] In the description of this utility model, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0021] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed", "equipped with", "sleeved / connected", "connected", etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0022] See Figure 1 This invention provides a continuous reactor for o-chlorobenzyl chloride, comprising a mixing tank 1, an agitator powered by a rotary motor connected to the mixing tank 1, the mixing tank 1 for mixing liquid reactants (e.g., chlorotoluene) with a catalyst, the outlet of the mixing tank 1 being connected to the inlet of a diversion pump 2 via a pipe, the diversion pump 2 discharging the mixed liquid from the mixing tank 1, the outlet of the diversion pump 2 being connected to a reaction tower 3 via a pipe, providing a reaction site for the liquid reactants and gaseous reactants (e.g., chlorine). The liquid mixed in mixing tank 1 is introduced into reaction tower 3. Reaction tower 3 is connected to heat exchanger 4, and heat exchanger 4 is connected to gas-liquid separator 5. The liquid separated by heat exchanger 4 is returned to reaction tower 3 through a pipeline. There are return pipelines between heat exchanger 4, gas-liquid separator 5 and reaction tower 3. The gas separated by gas-liquid separator 5 is discharged through a pipeline. The liquid separated by gas-liquid separator 5 is returned to reaction tower 3 through the return pipeline between gas-liquid separator 5 and reaction tower 3. Reaction tower 3 is connected to receiving tank 6. The products generated by the reaction can enter receiving tank 6 for processing in the next step.

[0023] See Figure 1 Preferably, reaction tower 3 is a photochlorination reaction tower, which provides the necessary reaction conditions for the reactants.

[0024] See Figure 1 Specifically, reaction tower 3 includes an upper section, an intermediate section, and a lower section. The diameter of the upper section of reaction tower 3 is larger than that of the intermediate and lower sections. The upper section is equipped with a feed port, a discharge port, and a spare port. The intermediate section consists of several layers. The outer walls of the intermediate and lower sections are equipped with jackets and sight glasses for heating or cooling (chlorine gas usually enters reaction tower 3 from the top three-quarters of the way down). A thermometer sleeve and thermometer for displaying the reaction temperature are installed on the outer periphery of the middle layer, and a support is installed on the outer periphery of the bottom layer. The lower section is equipped with a light source incident device, including a light source incident hole and a glass sight glass. The lower part of the lower section is equipped with a chlorine gas inlet and a sampling port. Some other conventional structures of the upper, intermediate, and lower sections of reaction tower 3 are the same as those of the photochlorination reaction tower. Their specific structures and connection methods will not be described in detail here.

[0025] See Figure 1 Specifically, in actual use, the pipelines between various devices will be equipped with corresponding valves, flow meters and other structures as needed. This is a mature existing technology in the field and a conventional technical means for those skilled in the art to engage in chemical production. Its specific structure and working principle will not be described in detail here.

[0026] See Figure 1 Furthermore, a buffer tank 7 is provided between the mixing tank 1 and the reaction tower 3. The buffer tank 7 can temporarily store the liquid mixed in the mixing tank 1, making it easier to introduce it into the reaction tower 3. The reaction tower 3 is equipped with a distributor, which can divide the introduced liquid to ensure that it reacts fully.

[0027] See Figure 1 Preferably, the receiving tank 6 is connected to the heat exchanger 4, and a return pipe is provided between the heat exchanger 4 and the receiving tank 6. The gas separated by the heat exchanger 4 is merged with the gas separated by the gas-liquid separator 5 through the pipe and then discharged through the pipe. The liquid separated by the heat exchanger 4 at the receiving tank 6 is returned to the receiving tank 6 through the pipe.

[0028] See Figure 1 In actual production, chlorotoluene and the catalyst are first mixed in mixing tank 1, and then the mixed liquid is introduced into reaction tower 3 using a diversion pump 2. Chlorine gas is then introduced into reaction tower 3 (see...). Figure 1 Chlorine gas enters from the chlorine inlet at the bottom of reaction tower 3, i.e. Figure 1 The "A" port in the diagram refers to the control of reaction conditions in reaction tower 3, such as the control of light and temperature, which are all mature existing technologies in this field and will not be elaborated here. The generated hydrogen chloride gas is recovered by using heat exchanger 4 and gas-liquid separator 5. The products generated in the reaction in reaction tower 3 enter receiving tank 6.

[0029] This invention provides a continuous reactor for the reaction of o-chlorobenzyl chloride, comprising a mixing tank and a reaction tower. It enables continuous feeding and discharging of chlorine gas and chlorotoluene through heating and mixing, ensuring product quality and improving reaction conversion rate. The combination of the mixing tank and reaction tower effectively reduces the generation of by-products, ensuring reaction yield. The combination of a heat exchanger and a gas-liquid separator recovers the generated hydrogen chloride gas, saving production costs. In summary, the beneficial effects of this invention are: continuous feeding and discharging of chlorine gas and chlorotoluene through heating and mixing, improving reaction conversion rate, reducing by-product generation, and ensuring reaction yield.

[0030] Of course, there may be other embodiments of this utility model. Without departing from the spirit and essence of this utility model, those skilled in the art can make various corresponding changes and modifications based on this utility model, but these corresponding changes and modifications should all fall within the protection scope of the appended claims of this utility model.

Claims

1. A continuous reactor for o-chlorobenzyl chloride, characterized in that, Includes a mixing tank for mixing liquid reactants with a catalyst, the mixing tank being connected via a pipeline to a reaction tower for providing a reaction site for the liquid and gaseous reactants; The reaction tower is connected to a heat exchanger, the heat exchanger is connected to a gas-liquid separator, and the reaction tower is connected to a receiving tank for receiving reaction products.

2. The continuous reactor for o-chlorobenzyl chloride according to claim 1, characterized in that, A flow guide pump is installed on the pipeline between the mixing tank and the reaction tower.

3. The continuous reactor for o-chlorobenzyl chloride according to claim 1, characterized in that, The mixing tank is equipped with a rotatable stirring paddle.

4. The continuous reactor for o-chlorobenzyl chloride according to claim 1, characterized in that, A reflux pipe is provided between the heat exchanger, the gas-liquid separator, and the reaction tower.

5. The continuous reactor for o-chlorobenzyl chloride according to claim 4, characterized in that, The liquid separated by the gas-liquid separator flows back to the reaction tower through the reflux pipe between the gas-liquid separator and the reaction tower.

6. The continuous reactor for o-chlorobenzyl chloride according to claim 1, characterized in that, The reaction tower includes an upper tower section, an intermediate tower section, and a lower tower section. The outer walls of the intermediate tower section and the lower tower section are equipped with jackets, and the lower tower section is equipped with a light source incident device.

7. The continuous reactor for o-chlorobenzyl chloride according to claim 6, characterized in that, A buffer tank is provided between the mixing tank and the reaction tower. The buffer tank temporarily stores the liquid mixed in the mixing tank and then introduces it into the reaction tower. The reaction tower is equipped with a distributor to divert the introduced liquid.

8. The continuous reactor for o-chlorobenzyl chloride according to claim 1, characterized in that, The receiving tank is connected to a heat exchanger, and a return pipe is provided between the heat exchanger and the receiving tank. The gas separated by the heat exchanger is discharged after merging with the gas separated by the gas-liquid separator through the pipe. The liquid separated by the heat exchanger at the receiving tank is returned to the receiving tank through the return pipe.

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