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

Method for manufacturing tolylene diisocyanate

A technology of toluene diisocyanate and its manufacturing method, which is applied to the preparation of carbamate, isocyanic acid derivatives, carbamic acid derivatives, etc., and can solve the problems of device corrosion, cumbersome handling, and strong toxicity of phosgene

Active Publication Date: 2014-01-01
MITSUI CHEM INC
View PDF8 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, phosgene is highly toxic, its handling is cumbersome, and a large amount of hydrochloric acid is generated in a side reaction. Therefore, there are various problems such as corrosion of equipment, etc., and the development of industrial production of toluene diisocyanate that can replace the phosgene method is desired. method

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
  • Method for manufacturing tolylene diisocyanate

Examples

Experimental program
Comparison scheme
Effect test

manufacture example 1

[0224] (Urethane Manufacturing Process)

[0225] Put the first diaminotoluene (2,4-diaminotoluene / 2,6-diaminotoluene= 80 / 20 (molar ratio)) (122g: 1mol), butyl carbamate (333g: 2.85mol) and 1-butanol (211g: 2.85mol), zinc p-toluenesulfonate (1.0g: 2.5mmol) as a catalyst ), while feeding nitrogen with a flow rate of 1 L per minute and stirring at 500 rpm, while adjusting the internal pressure with a pressure control valve, so that the reaction temperature remained at 200 ° C, reacted for 8 hours to obtain a reaction solution.

[0226] A part of the reaction solution was collected and quantified, and the results were confirmed. 2,4-bis(butoxycarbonylamino)toluene (2,4-toluene dicarbamate) and 2,6-bis(butoxycarbonylamino) Toluene dicarbamate was obtained at a yield of 95 mol% based on the total amount of toluene (2,6-toluene dicarbamate).

[0227] (decompression distillation removal of light boiling components)

[0228] 387.77 g of the reaction liquid obtained by the above-ment...

Embodiment 1

[0239] 100 g of the first diaminotoluene (2,4-diaminotoluene / 2,6-diaminotoluene=80 / 20 (molar ratio)) was used as the decomposed diaminotoluene obtained in Production Example 1 of the second diaminotoluene (2,4-diaminotoluene / 2,6-diaminotoluene=95 / 5 (molar ratio)) 21 g were mixed, and mixed diaminotoluene was obtained (mixing process).

[0240] The isomer ratio of the obtained mixed diaminotoluene was 2,4-diaminotoluene / 2,6-diaminotoluene=82.6 / 17.4 (molar ratio).

[0241] Except having used mixed diaminotoluene instead of the 1st diaminotoluene, it carried out similarly to manufacture example 1, and toluene dicarbamate was obtained. In addition, it was confirmed that 2,4-bis(butoxycarbonylamino)toluene (2,4-toluene dicarbamate) and 2,6-bis(butoxycarbonylamino)toluene (2, 6-toluene dicarbamate) was obtained at a yield of 95 mol % based on the total amount of toluene dicarbamate.

[0242] Moreover, except having used the obtained toluene dicarbamate, it carried out similarly to...

Embodiment 2

[0247] Toluene dicarbamate was obtained in the same manner as in Example 1, except that 27 g of the decomposed diaminotoluene (second diaminotoluene) obtained in Production Example 1 was mixed with 100 g of the first diaminotoluene. It should be noted that it was confirmed that 2,4-bis(butoxycarbonylamino)toluene (2,4-toluene dicarbamate) and 2,6-bis(butoxycarbonylamino)toluene (2, 6-toluene dicarbamate) was obtained at a yield of 95 mol % based on the total amount of toluene dicarbamate.

[0248] The isomer ratio of mixed diaminotoluene is 2,4-diaminotoluene / 2,6-diaminotoluene=83.2 / 16.8 (molar ratio).

[0249] Moreover, except having used the obtained toluene dicarbamate, it carried out similarly to Example 1, distilled off the light boiling component under reduced pressure, and thermally decomposed the obtained concentrate, and obtained toluene diisocyanate, and obtained the filter residue.

[0250] As a result of quantification by HPLC, the yield of the obtained toluene di...

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
thermal degradation temperatureaaaaaaaaaa
thermal degradation temperatureaaaaaaaaaa
Login to View More

Abstract

A method for manufacturing tolylene diisocyanate comprises a mixing step, a carbamate manufacturing step, and a pyrolysis step. In the mixing step, a first diaminotoluene containing 2,4- and 2,6-diaminotoluene in a first isomeric ratio is mixed with a second diaminotoluene containing 2,4- and / or 2,6-diaminotoluene in a second isomeric ratio, and mixed diaminotoluene is prepared. In the carbamate manufacturing step, a reaction is brought about between the mixed diaminotoluene prepared in the mixing step, urea and / or N-unsubstituted carbamate, and an alcohol, whereby tolylene dicarbamate is produced. In the pyrolysis step, the tolylene dicarbamate is pyrolyzed.

Description

technical field [0001] The present invention relates to a method for producing toluene diisocyanate. Specifically, it relates to a method for producing toluene diisocyanate containing 2,4-toluene diisocyanate and 2,6-toluene diisocyanate in a desired isomer ratio. Background technique [0002] Toluene diisocyanate is well known as a general-purpose isocyanate used as a raw material for polyurethane, polyurea, and the like. [0003] Conventionally, toluene diisocyanate has been industrially produced by the reaction of diaminotoluene and phosgene (phosgene method). However, phosgene is highly toxic, its handling is cumbersome, and a large amount of hydrochloric acid is generated in a side reaction. Therefore, there are various problems such as corrosion of equipment, etc., and the development of industrial production of toluene diisocyanate that can replace the phosgene method is desired. method. [0004] In general, as a method for producing toluene diisocyanate without usi...

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): C07C263/04C07C265/14
CPCC07C263/20C07C263/06C07C265/14C07C263/00C07C263/04C07C269/04C07C271/28
Inventor 高松孝二小角和广福田伟志佐佐木祐明
Owner MITSUI CHEM INC
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