Isocyanate monomer preparation method and system

An isocyanate and monomer technology, applied in the field of phosgenation reaction to prepare isocyanate, can solve the problems of long process flow, many side reactions and high energy consumption, and achieve the effects of simple process, stable product quality and high yield

Active Publication Date: 2019-05-14
WANHUA CHEM GRP CO LTD +1
View PDF25 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The technical problem to be solved by the present invention is to provide a process for preparing isocyanate monomer, which can overcome the technical problems of long traditional process flow, many side reactions, high energy consumption and low yield

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
  • Isocyanate monomer preparation method and system
  • Isocyanate monomer preparation method and system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0066] Using the above process steps, add toluene in the normal pressure reactor, stir and heat up after nitrogen replacement, use toluene as solvent, introduce methylamine hydrochloride and phosgene at a molar ratio of 1:10, 4kgf / cm 2The reaction is carried out at 110°C. After the reaction, the reaction product including carbamoyl chloride, phosgene, and HCl is heated to 75-80°C. The reaction product enters the gas-liquid separator, and then passes through the reaction gas phase condenser. Use 10-25 The chilled water at ℃ controls the temperature of the condenser, and the uncondensed phosgene and hydrogen chloride enter the phosgene absorption treatment process, and the condensed liquid including carbamoyl chloride and isocyanate is exchanged with toluene in a static state after heat exchange in the reaction gas phase condenser to 15-30 ℃ Mix in mixer, methylcarbamoyl chloride (MCC): toluene=1:8 (m / m), triethylamine is neutralizer, methylcarbamoyl chloride (MCC): triethylamine...

Embodiment 2

[0069] Using the above process steps, add o-dichlorobenzene in the normal pressure reactor, stir and heat up after nitrogen replacement, use o-dichlorobenzene as solvent, introduce methylamine hydrochloride and phosgene at a molar ratio of 1:10, 5kgf / cm 2 The reaction is carried out at 110°C and 150°C to generate, and the reaction products obtained after the reaction including ethylcarbamoyl chloride, phosgene, and HCL are heated to 100-105°C and then enter the gas-liquid separator, which is controlled by 15-30°C chilled water The uncondensed phosgene and hydrogen chloride at the temperature of the condenser pass through the reaction gas phase condenser and then enter the phosgene absorption treatment process, including the condensed liquid of ethylcarbamoyl chloride and ethyl isocyanate condensed to 25-35°C, and o-dichlorobenzene Mix in a static mixer, carbamoyl chloride (MCC): o-dichlorobenzene = 1:8 (m / m), triethylamine as neutralizer, carbamoyl chloride (MCC): triethylami...

Embodiment 3

[0071] Afterwards, several synthesis experiments were carried out and tested, and compared with the conventional cleavage reaction, the comparison results are shown in Table 1.

[0072] Table 1. Comparison of indicators of the two processes

[0073] Test items

[0074] In the above implementation examples, Agilent 7890 was used to measure the purity and concentration of the reaction solution. IR is tested using FTIR.

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

No PUM Login to view more

Abstract

The invention discloses an isocyanate monomer preparation method and system. The method includes that amine hydrochloride and phosgene are continuously added into a reaction kettle, a reaction temperature is controlled, and generated isocyanate, HCl, acyl chloride and the like are gasified prior to entering an intermediate product kettle; after the gas flows through a condenser, intermediates suchas acyl chloride are condensed and participate in neutralization reaction, acyl chloride is subjected to organic alkali catalytic reaction to obtain isocyanate, and then a pure product is obtained through separation; phosgene and HCl enter secondary condensation, and condensed phosgene is recycled in the reaction kettle. Compared with a traditional pyrolyzing process, the method and the system have advantages that stability in system control, high yield, low energy consumption and low equipment investment are realized; pyrolyzing procedures are reduced, pyrolyzer cleaning is avoided, and material leakage and personnel safety risks are reduced.

Description

technical field [0001] The present invention relates to a method and system for preparing isocyanate monomers, and more particularly, to a method and system for preparing isocyanates that can be used in phosgenation reactions. Background technique [0002] In the prior art, the phosgenation method of preparing various isoamyl esters by reacting organic primary amines and phosgene in an inert solvent is well known. [0003] Published patent CN 102659631 A reports the preparation of ethyl isocyanate by one-step method, using triphosgene and ethylamine hydrochloride as raw materials, xylene as solvent, adding catalyst, heating to above 135°C for reaction, and analyzing the reaction degree in the middle control; the separation process adopts For rectification (tray 40), first heat to reflux to remove acid gas, then accept the target product at 50-70°C, the purity of the obtained product is more than 99%, and the yield is 87%. Through the description of this patent, many problem...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07C263/10C07C263/20C07C265/04
Inventor 李建峰尚永华乔小飞陈浩李同和俞勇华卫琦
Owner WANHUA CHEM GRP CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap