Chloroformate synthesis reactor

Abstract

The utility model provides a chloroformate synthesis reactor. The chloroformate synthesis reactor comprises a tower body and a tower kettle, the top of the tower body is provided with a tail gas outlet, the upper end of the side wall is provided with a chloroformate overflow discharge port, and the outer side is provided with a cooling jacket; a cooling jacket is arranged on the outer side of the tower kettle, a feeding hole is formed in the bottom, and a distribution plate and a cooler are arranged in an inner cavity; the feed port is of a sleeve structure and comprises an inner pipe and an outer pipe, the inner pipe is an alcohol feed port, and the outer pipe is a phosgene feed port; the distribution disc comprises a horizontally arranged annular pipe, a connecting pipe for communicating the annular pipe with the phosgene feeding hole, and a plurality of gas outlet nozzles communicated with the annular pipe; and the cooler is positioned above the distribution disc. The chloroformate synthesis reactor disclosed by the utility model is reasonable in structural design, can realize rapid and uniform mixing of phosgene and alcohol raw materials, improves the reaction rate, avoids the situation of side reaction caused by local excessive alcohol, and improves the product quality.

Description

Technical Field

[0001] The utility model belongs to the field of chloroformate production equipment, and particularly relates to a chloroformate synthesis reactor. Background Art

[0002] Chloroformate compounds are a kind of intermediates with wide applications, and are often used in the synthesis of pharmaceutical compounds, pesticide compounds, etc. There are various types of chloroformate compounds. In industry, chloroformate products are mainly prepared by reacting the corresponding alcohols with phosgene, and the kettle reaction is often adopted. A certain amount of alcohol is added into the kettle at one time, and then phosgene is introduced for reaction. This method has problems such as local excess of alcohols, uneven distribution of phosgene, poor mixing effect of raw materials, and affecting product quality. Therefore, in the prior art, a photochemical tower is used for reaction, alcohols and phosgene are continuously introduced from the bottom of the tower, the tail gas is discharged from the top of the tower, and chloroformate products overflow and are produced from the upper side wall near the top of the tower body. The inlet modes of alcohols and phosgene adopt a sleeve structure, and the gas-liquid cutting and mixing are realized by using the conveying pressure of phosgene. This feeding mode can optimize the mixing effect of raw materials to a certain extent and reduce the occurrence of side reactions due to local excess of alcohols. However, it only relies on the conveying pressure of phosgene at the feed inlet for gas-liquid cutting and mixing, and the effect is limited, and further optimization is still needed. Summary of the Utility Model

[0003] In view of this, to solve the above technical problems, the utility model provides a chloroformate synthesis reactor. By optimizing the phosgene feeding structure at the bottom of the tower kettle, the rapid and uniform mixing of phosgene and alcohol raw materials can be realized, the reaction rate can be increased, the occurrence of side reactions due to local excess of alcohols can be avoided, and the product quality can be improved. At the same time, by arranging a cooler in the tower kettle, the reaction heat can be quickly removed.

[0004] To achieve the above object, the technical solution of the utility model is realized as follows:

[0005] A chloroformate synthesis reactor, comprising a tower body and a tower kettle located at the bottom of the tower body;

[0006] The top of the tower body is provided with a tail gas outlet, the upper end of the side wall is provided with a chloroformate overflow discharge port, and the outside is provided with a cooling jacket;

[0007] The outside of the tower kettle is provided with a cooling jacket, the bottom is provided with a feed inlet, and the inner cavity is provided with a distribution plate and a cooler; the feed inlet is of a sleeve structure, including an inner tube and an outer tube. The inner tube is an alcohol feed inlet, and the outer tube is a phosgene feed inlet; the distribution plate includes a horizontally arranged annular tube, a connecting tube connecting the annular tube and the phosgene feed inlet, and a plurality of gas outlet nozzles communicating with the annular tube; the cooler is located above the distribution plate.

[0008] Phosgene and alcohols are continuously fed into the bottom of the column kettle through a double pipe. The inner layer is the liquid raw material alcohol, and the outer layer is the gaseous raw material phosgene. The conveying pressure of phosgene is used to realize the cutting of gas and liquid, improve the mixing speed. At the same time, phosgene enters the annular pipe through the connecting pipe and then is output from the air outlet nozzle, realizing the cutting and mixing of gas and liquid in multiple directions. The distribution of phosgene is more uniform and the fluidity is better, effectively improving the reaction rate and the utilization rate of phosgene, and avoiding the occurrence of side reactions due to local excess of alcohols. At the same time, a cooler is provided. When phosgene and alcohols are continuously fed and the photochemical reaction is continuously carried out, it cooperates with the cooling jacket to quickly remove the reaction heat, improve the reaction rate and optimize the reaction effect. The chloroformate generated in the column flows out from the chloroformate overflow outlet on the column body and enters the subsequent deacidification process. Nitrogen is filled in the gas-evolving kettle to drive out the gas, and a qualified chloroformate product is obtained. The generated tail gas flows out from the tail gas outlet and enters the subsequent tail gas treatment process for tail gas treatment.

[0009] Further, the annular pipe is located directly above the feed port; a plurality of the air outlet nozzles are circumferentially and equally spaced on the inner side wall of the annular pipe, realizing gas-liquid cutting at multiple angles and improving the mixing speed.

[0010] Further, a plurality of the air outlet nozzles are inclined in the counterclockwise or clockwise direction on the same horizontal plane.

[0011] Further, the cooler includes a cooling pipe and a cold medium inlet and a cold medium outlet provided at both ends of the cooling pipe and communicating with the inner cavity of the cooling jacket outside the column kettle.

[0012] The cold medium in the cooling jacket enters the cooler and cools the liquid material inside the column kettle. Cooperating with the cooling jacket, it realizes simultaneous internal and external cooling at the column kettle, can quickly remove the reaction heat, improve the reaction efficiency and shorten the production cycle.

[0013] Further, the cooler is a coiled pipe, and the cold medium inlet is located below the cold medium outlet and is arranged at an oblique diagonal position.

[0014] Further, the inner pipe and the outer pipe are coaxially arranged, and the feed end of the outer pipe is located on the side wall of the outer pipe.

[0015] Further, the column body is composed of a plurality of column sections. The tail gas outlet is located at the top of the uppermost column section, and the chloroformate overflow outlet is located on the side wall of the uppermost column section.

[0016] Further, an independent cooling jacket is provided on the outside of each column section. The coolant inlet end is located at the lower end of the cooling jacket, and the coolant outlet is located at the upper end of the cooling jacket.

[0017] Compared with the prior art, the chloroformate synthesis reactor of the present invention has the following advantages:

[0018] (1) The structural design of the chloroformate synthesis reactor of the present utility model is reasonable. A sleeve feeding method is adopted at the bottom of the tower kettle. The inner layer is the liquid raw material alcohol, and the outer layer is the gaseous raw material phosgene. The gas-liquid cutting is realized by using the conveying pressure of phosgene. At the same time, a distribution plate is set to realize the gas-liquid cutting and mixing in multiple directions, making the phosgene distribution more uniform and the fluidity better, effectively improving the reaction rate, increasing the utilization rate of phosgene, avoiding the situation of side reactions caused by local excess of alcohols, and improving the product quality;

[0019] (2) The chloroformate synthesis reactor of the present utility model is provided with a cooler in the tower kettle. When phosgene and alcohols are continuously fed and the photochemical reaction is carried out continuously, in cooperation with the cooling jacket, the simultaneous temperature reduction from the inside to the outside and from the outside to the inside can be realized, and the reaction heat can be quickly removed. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings that form a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0021] Figure 1 is a schematic structural diagram of the chloroformate synthesis reactor according to the embodiment of the present utility model;

[0022] Figure 2 is Figure 1 an enlarged view of part A of;

[0023] Figure 3 is a schematic structural diagram of the distribution plate according to the embodiment of the present utility model.

[0024] Description of the reference numerals:

[0025] 1 - tower kettle, 2 - tower section, 3 - tail gas outlet, 4 - chloroformate overflow outlet, 5 - cooling jacket, 6 - feed inlet, 7 - distribution plate, 8 - cooler, 9 - alcohol feed inlet, 10 - phosgene feed inlet, 11 - annular pipe, 12 - connecting pipe, 13 - gas outlet nozzle. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other.

[0027] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0028] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood through specific situations.

[0029] The present utility model will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0030] As Figures 1 to 3 shown, a chloroformate synthesis reactor includes a tower body and a tower kettle 1 located at the bottom of the tower body;

[0031] The tower body is composed of a plurality of tower sections 2. A tail gas outlet 3 is provided at the top of the topmost tower section 2, and a chloroformate overflow discharge port 4 is provided on the side wall of the topmost tower section 2; an independent cooling jacket 5 is provided outside each tower section 2, the coolant inlet end is located at the lower end of the cooling jacket 5, and the coolant outlet is located at the upper end of the cooling jacket 5;

[0032] A cooling jacket 5 is provided outside the tower kettle 1, a feed inlet 6 is provided at the bottom, and a distribution plate 7 and a cooler 8 are provided in the inner cavity; the feed inlet 6 is of a sleeve structure, including an inner tube and an outer tube, the inner tube and the outer tube are coaxially arranged, the feed end of the outer tube is located on the side wall of the outer tube, the inner tube is an alcohol feed port 9, and the outer tube is a phosgene feed port 10; the distribution plate 7 includes a horizontally arranged annular tube 11, a connecting tube 12 connecting the annular tube 11 and the phosgene feed port 10, and a plurality of gas outlet nozzles 13 communicating with the annular tube 11. The annular tube 11 is located directly above the feed inlet 6, and the plurality of gas outlet nozzles 13 are circumferentially and equally spaced on the inner side wall of the annular tube 11 in the same horizontal plane, and the plurality of gas outlet nozzles 13 are inclined counterclockwise or clockwise; the cooler 8 is located above the distribution plate 7. The cooler 8 includes a cooling tube and a cold medium inlet and a cold medium outlet provided at both ends of the cooling tube and communicating with the inner cavity of the cooling jacket 5 outside the tower kettle 1. The cooler is a serpentine tube, and the cold medium inlet is located below the cold medium outlet and is arranged at a diagonal position.

[0033] The working process of the chloroformate synthesis reactor of the present utility model is as follows:

[0034] Phosgene and alcohols (such as 2-ethylhexanol) are continuously fed into the bottom of the tower kettle 1 by means of a sleeve. The inner layer is the liquid raw material alcohol, and the outer layer is the gaseous raw material phosgene. The gas-liquid cutting is realized by using the conveying pressure of phosgene. At the same time, the multi-directional gas-liquid cutting and mixing are carried out by using the distribution plate 7. Phosgene and alcohols are continuously fed in. In the tower, the photochemical reaction is carried out at a certain temperature to generate chloroformate (such as (2-ethyl) hexyl chloroformate) and hydrogen chloride gas. The reaction heat is quickly removed by the cooling jacket 5 and the cooler 8;

[0035] The generated chloroformate flows out from the chloroformate overflow outlet 4 on the tower body and enters the subsequent deacidification process (in the gas-expelling kettle, at a certain temperature, nitrogen is filled into the gas-expelling kettle to expel gas. After sampling and detecting that the free chlorine is qualified, it is put into the finished product kettle and waiting for packaging) for treatment;

[0036] The tail gas contains the generated hydrogen chloride gas and a small amount of phosgene. The tail gas is sent into the tail gas treatment process under the action of a slight negative pressure (the tail gas enters the hydrochloric acid absorption tower, the hydrogen chloride gas is absorbed by water to form hydrochloric acid, and then enters the destruction tower. A small amount of phosgene generates HCl and CO2 gases under the action of the catalytic carrier. Then the remaining phosgene, HCl, and CO2 enter the alkali destruction tower for destruction and absorption to reach the qualified standard and are discharged into the atmosphere) for treatment.

[0037] The above description is only the preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A chloroformate synthesis reactor, comprising a tower body and a tower kettle located at the bottom of the tower body; characterized in that: The top of the tower body is provided with an exhaust gas outlet, the upper end of the side wall is provided with a chloroformate overflow outlet, and the outer side is provided with a cooling jacket; A cooling jacket is provided on the outside of the tower kettle, a feed port is provided on the bottom, and a distribution plate and a cooler are provided in the inner cavity; the feed port is a sleeve structure, including an inner tube and an outer tube, the inner tube is an alcohol feed port, and the outer tube is a phosgene feed port; the distribution plate includes a horizontally arranged ring pipe, a connecting pipe connecting the ring pipe and the phosgene feed port, and a plurality of gas outlet nozzles connected to the ring pipe; the cooler is located above the distribution plate.

2. The chloroformate synthesis reactor according to claim 1, characterized in that: The annular tube is located directly above the feed port; and a plurality of the gas outlet nozzles are distributed on the inner side wall of the annular tube at equal intervals along the circumferential direction.

3. The chloroformate synthesis reactor according to claim 2, characterized in that: The plurality of air outlet nozzles are arranged on the same horizontal plane and are tilted in a counterclockwise or clockwise direction.

4. The chloroformate synthesis reactor according to claim 1, characterized in that: The cooler comprises a cooling pipe and a cooling jacket inner cavity provided at both ends of the cooling pipe and connected with a cold medium inlet and a cold medium outlet on the outside of the tower kettle.

5. The chloroformate synthesis reactor according to claim 4, characterized in that: The cooler is a serpentine tube, and the cold medium inlet is located below the cold medium outlet and is arranged at a diagonal position.

6. The chloroformate synthesis reactor according to claim 1, characterized in that: The inner tube and the outer tube are arranged coaxially, and the feed end of the outer tube is located on the side wall of the outer tube.

7. The chloroformate synthesis reactor according to any one of claims 1 to 6, characterized in that: The tower body is composed of a plurality of tower sections, the tail gas outlet is located at the top of the uppermost tower section, and the chloroformate overflow outlet is located at the side wall of the uppermost tower section.

8. The chloroformate synthesis reactor according to claim 7, characterized in that: An independent cooling jacket is arranged on the outer side of each tower section, a cooling liquid inlet is located at the lower end of the cooling jacket, and a cooling liquid outlet is located at the upper end of the cooling jacket.

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