Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Preparation method of isocyanate

A technology of isocyanate and amine hydrochloride, applied in the direction of organic chemistry, can solve the problems of uneven dispersion, shorten the time of thermophotochemical reaction, etc., and achieve the effect of increasing solubility and improving uneven distribution

Active Publication Date: 2016-01-06
WANHUA CHEM GRP
View PDF22 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0019] The object of the present invention is to provide a kind of method for preparing isocyanate, based on salt-forming phosgenation reaction, under the situation that does not reduce the concentration of salt-forming reaction amine hydrochloride, adopt traditional salt-forming reactor to carry out preliminary salt-forming reaction, subsequently Salt-forming and aging reactions are carried out in the salt-forming and aging reactor, and a certain proportion of low-molecular-weight ketones or nitrile solvents are added to the hydrochloride slurry to improve the dispersion of the hydrochloride slurry in traditional halogenated aromatic hydrocarbon inert solvents. Uniformity, so that the micro-scale distribution of the hydrochloride slurry is more uniform, and a hydrochloride slurry with a high conversion rate and uniform particle size distribution can be obtained, thereby shortening the thermal photochemical reaction time, reducing the generation of by-products in the photochemical process, and improving Final product isocyanate yield and product quality

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of isocyanate
  • Preparation method of isocyanate
  • Preparation method of isocyanate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0106] An autoclave with a jet reactor, a phosgene blowing tube and agitation was used as reaction equipment for step a, with a volume of 10 liters. Put 817g (6mol) of m-xylylenediamine and 7354g of o-dichlorobenzene (total amine concentration of feed is 10wt%) into the raw material tank to form m-xylylenediamine solution (or called reaction solution). The temperature of the reaction solution was kept at 20°C by means of external cooling. Hydrogen chloride gas is passed in the nozzle of jet reactor by high-pressure pump, and the feed rate of hydrogen chloride is 8L / min, starts to inject m-xylylene dimethoxane by the nozzle of jet reactor with the speed of 158g / min at the same time Amine solution, and at the same time, the stirring of the reactor was started to carry out the preliminary salt-forming reaction.

[0107] The salt-forming and aging reaction kettle used in this example adopts an hourglass-shaped liquid slurry disperser with equal upper and lower end surface areas. ...

Embodiment 2

[0111] The same tank reactor as in Example 1 was used. Put 817g (6mol) of m-xylylenediamine and 7354g of o-dichlorobenzene (total amine concentration of feed is 10wt%) into the raw material tank to form m-xylylenediamine solution (or called reaction solution). The temperature of the reaction solution was kept at 20°C by means of external cooling. Hydrogen chloride gas is passed in the nozzle of jet reactor by high-pressure pump, and the feed rate of hydrogen chloride is 8L / min, starts to inject m-xylylene dimethoxane by the nozzle of jet reactor with the speed of 158g / min at the same time Amine solution, and at the same time, the stirring of the reactor was started to carry out the preliminary salt-forming reaction.

[0112] The salt-forming and aging reaction kettle used in this example adopts an hourglass-shaped liquid slurry disperser with equal upper and lower end surface areas. The height of the hourglass-shaped liquid slurry disperser is 1 / 3 of the height of the tank re...

Embodiment 3

[0116] The same tank reactor as in Example 1 was used. Put 1225g (9mol) of m-xylylenediamine and 6946g of o-dichlorobenzene (total amine concentration of feed is 15wt%) into the raw material tank to form m-xylylenediamine solution (or called reaction solution). The temperature of the reaction solution was kept at 20°C by means of external cooling. Hydrogen chloride gas is passed into the nozzle of jet reactor by high-pressure pump, and the feeding speed of hydrogen chloride is 12L / min, starts to inject m-xylylene dimethyl dimethacrylate by the nozzle of jet reactor with the speed of 158g / min simultaneously with material pump. Amine solution, and at the same time, the stirring of the reactor was started to carry out the preliminary salt-forming reaction.

[0117] The salt-forming and aging reaction kettle used in this example adopts an hourglass-shaped liquid slurry disperser with unequal upper and lower end surface areas. The height of the hourglass-shaped liquid slurry dispe...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Number average particle sizeaaaaaaaaaa
Number average particle sizeaaaaaaaaaa
Number average particle sizeaaaaaaaaaa
Login to View More

Abstract

The invention provides a method for preparing isocyanate based on a salifying phosgenation method. A salt forming reaction in the method comprises the following two steps: firstly, performing preliminary salt forming reaction by adopting a conventional reactor; secondly, adding a moderately polar organic solvent with a certain proportion into a reactor provided with an hourglass type liquid slurry disperser to carry out salt forming curing reaction, wherein star-shaped discharge openings are arrayed in a cylinder body of the hourglass type disperser. According to the preparation method, the fact that amino groups in raw materials are converted into amine hydrochlorides with high conversion rate can be ensured through the salt forming curing reaction, and the isocyanate product can be obtained with high yield through a follow-up photochemical reaction.

Description

technical field [0001] The invention relates to a method for preparing isocyanate, in particular to a method for preparing isocyanate by a salt-forming phosgenation method, and belongs to the field of isocyanate preparation by phosgenation. Background technique [0002] Isocyanate is a kind of special chemical with -N=C=O functional group. The high reactivity of -N=C=O functional group makes it widely used as synthetic intermediate of pesticide, medicine and other fine chemical products and synthetic raw material of polyurethane material. Polyurethane materials based on isocyanate are widely used in construction, vehicles, household appliances, aerospace, electromechanical, shipbuilding, chemical industry, metallurgy and mining, light industry, textile, Various fields of national economy and national defense construction such as medical care and health. [0003] Aliphatic (cyclic) isocyanate (ADI) is a special isocyanate product in which the -N=C=O functional group in the m...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): C07C331/30
Inventor 史培猛尚永华李建峰韩金平孙中平黎源华卫琦
Owner WANHUA CHEM GRP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com