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Method and device for preparing diisocyanate

A technology of diisocyanate and gas distribution device, which is applied in the preparation of isocyanic acid derivatives, chemical instruments and methods, and the preparation of organic compounds, etc.

Active Publication Date: 2021-04-30
ANHUI DONGZHI GUANGXIN AGROCHEMICAL CO LTD
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The process of preparing diisocyanate by gas-phase phosgenation is a fast reaction process. In order to ensure the reaction speed, higher temperature reaction temperature and wall surface temperature are often used, which cannot avoid the formation of chlorine-containing by-products and monofunctional isocyanate impurities. Therefore, it is necessary to find a A method capable of efficiently and quickly mixing reactants and effectively removing reaction by-products and deposits

Method used

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  • Method and device for preparing diisocyanate
  • Method and device for preparing diisocyanate
  • Method and device for preparing diisocyanate

Examples

Experimental program
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Effect test

Embodiment 1

[0051] use as Figure 1~2 The reactor shown. There are 2 phosgene feed nozzles and 2 diamine feed nozzles on the tubular reactor, and the phosgene and diamine feed nozzles are arranged alternately and uniformly at horizontal intervals. The angle is 90°C. Wherein the diameter of the impact reaction zone d1=0.6D, the speed at which phosgene enters the impact area is 20 m / s, and the speed at which diamine enters the impact area is 20 m / s. Disc diameter d2 = 0.7D, 100mm away from the impact area. The average residence time of the two materials in the impact zone was 0.2 seconds. D is 0.5 meters. The distance between the tubular gas distribution equipment and the top of the tubular shell is 80mm, and the distance between the steady-state impact zone and the steady-state impact zone is 100mm, the inert medium is nitrogen, and the speed of refraction to the impact reaction zone is 4 m / s. The heat transfer section on the upper part of the tubular shell rapidly reacts to keep the ...

Embodiment 2

[0056] use as Figure 1~2 The reactor shown. There are 2 phosgene feed nozzles and 2 diamine feed nozzles on the tubular reactor, and the phosgene and diamine feed nozzles are arranged alternately and evenly spaced horizontally. The angle is 45°C. Wherein the diameter of the impact reaction zone d1=0.65D, the speed at which phosgene enters the impact area is 18 m / s, and the speed at which diamine enters the impact area is 18 m / s. The average residence time of the two materials in the impact zone was 0.3 seconds. D is 0.7 meters. The distance between the pipe-type gas distribution equipment and the top of the pipe-type shell is 60mm, and the distance between the steady-state impact zone and the steady-state impact zone is 200mm, the inert medium is nitrogen, and the speed of refraction to the impact reaction zone is 4 m / s. The heat transfer section on the upper part of the tubular shell rapidly reacts to keep the wall temperature of the shell at 280°C, and the distance of t...

Embodiment 3

[0061] use as Figure 2~3 The reactor shown. There are 2 phosgene feed nozzles and 2 diamine feed nozzles on the tubular reactor, and the phosgene and diamine feed nozzles are arranged alternately and uniformly at horizontal intervals. angle is 90°C, this figure 2 There are two sets of components shown, with the second set located in the middle of the reactor. Wherein the diameter of the impact reaction zone d1=0.6D, the speed at which phosgene enters the impact area is 30 m / s, and the speed at which diamine enters the impact area is 30 m / s. Disk diameter d2 = 0.6D, 100mm away from the impact area. The average residence time of the two materials in the impact zone was 0.3 seconds. D is 1 meter. The distance between the pipe-type gas distribution equipment and the top of the pipe-type shell is 80mm, and the distance between it and the steady-state impact zone is 100mm, the inert medium is nitrogen, and the speed of refraction to the impact reaction zone is 8 m / s. The hea...

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Abstract

The invention discloses a reactor and a method for preparing diisocyanate by adopting a low-temperature gas phase method. The tubular reactor comprises a tubular shell, an external jacket and gas distribution equipment positioned at the top of the shell, and the shell is provided with at least one group of uniformly distributed feeding nozzles; and one group of feeding nozzles comprise at least one phosgene feeding nozzle and at least one diamine feeding nozzle, reaction materials are sprayed out through the nozzles and then collide with each other in a middle collision area, the reaction effect is enhanced, and the gas distribution equipment is located at the top of the shell and at the upper parts of the feeding nozzles. Inert media are evenly distributed through the gas distribution equipment and then refracted to the impact reaction area at the top of the shell, the temperature and concentration of the reaction area are reduced, phosgene and amine mixing can be enhanced through the reactor, the inert media are continuously diluted, heat released by reaction is removed in time, and generation of byproducts at high temperature is reduced. The wall surface temperature of each area of the tubular shell is controlled to reduce wall surface coking substances, the reaction yield is improved, and the operation period of reaction equipment is prolonged.

Description

technical field [0001] The invention belongs to the field of organic chemical industry, and relates to a method for preparing isocyanate and a device thereof, in particular to a low-temperature gas-phase high-efficiency reactor and a method for preparing isocyanate through a gas-phase phosgenation process using the reactor. Background technique [0002] Isocyanates are a class of organic compounds containing -N=C=O functional groups. Diisocyanates refer to compounds containing two such functional groups. Diisocyanates generally have high reactivity and are very easy to react with compounds containing active hydrogen. It is an important organic synthesis intermediate. Since Wurtz first prepared alkyl isocyanate in 1849, humans have been exploring various isocyanate products with special structures and properties and developing various methods for preparing isocyanate. [0003] At present, diisocyanate products mainly include aromatic, aliphatic and alicyclic isocyanates. Ali...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07C263/10C07C265/14B01J19/18
CPCC07C263/10B01J19/18B01J19/0053B01J19/0066C07C2601/16C07C265/14
Inventor 陈斌陈永贵过学军黄中桂袁晓林丁锐熊刚朱智慧师媛媛安亚萍
Owner ANHUI DONGZHI GUANGXIN AGROCHEMICAL CO LTD