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

Method for preparing aromatic dimethyl chloride

A diacid chloride and aromatic technology, which is applied in the field of preparation of aromatic diacid chloride, can solve the problems of many by-products, low purity, and low product purity, and achieve the effect of increasing yield and improving purity

Inactive Publication Date: 2011-06-15
YANTAI TAYHO ADVANCED MATERIALS CO LTD
View PDF2 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The carboxylic acid acylation method refers to the acylation of aromatic carboxylic acids with a certain acylating agent to directly obtain the product; the carboxylate chlorination method refers to the method of producing acid chlorides by reacting aromatic carboxylic acid esters with chlorine gas, but this method The conversion rate of raw materials is not high, and the purity of the produced products is also low; the substituted benzene is first chlorinated and then hydrolyzed, which means that the alkyl substituted benzene is first chlorinated with chlorine, and then hydrolyzed to obtain the target product. The reaction conditions of this method are not easy to control, and the side effects There are many products, and the purity of the produced products is not high
Relatively speaking, the acylation method is a better method, but the acylation method has the disadvantages of low yield and low purity

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 preparing aromatic dimethyl chloride
  • Method for preparing aromatic dimethyl chloride

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0012] Embodiment 1, preparation isophthaloyl dichloride

[0013] Add 3300Kg of thionyl chloride and 12Kg of pyridine into the batching tank, stir and mix, and after mixing, add them into the synthesis kettle together with 1500Kg of isophthalic acid. Turn on the vacuum pump, reflux condenser and tail gas absorption device, control the vacuum degree to 40mmHg, and react at 80°C for 20 hours. After the reaction is completed, increase the vacuum degree to be greater than or equal to 0.09MPa, control the temperature in the kettle to 115°C, and recover the thionyl chloride by evaporation. Feed nitrogen into the kettle, keep the vacuum degree greater than or equal to 0.09MPa, control the temperature in the kettle to 125°C, and exhaust the waste gas in the kettle. Cool the reaction solution to 90°C and transfer it to the still, raise the temperature of the still to 120-130°C under a vacuum of 0.09MPa, collect about 130Kg of the fore distillation, and collect in the range of 130-140°...

Embodiment 2

[0015] Embodiment 2, preparation terephthaloyl chloride

[0016] Add 3250Kg of thionyl chloride and 11.5Kg of N-methylpyrrolidone into the batching tank, stir and mix, and after mixing, add them into the synthesis kettle together with 1500Kg of terephthalic acid. Turn on the vacuum pump, reflux condenser and tail gas absorption device, control the vacuum degree to 40mmHg, and react at 110°C for 20 hours. After the reaction is completed, increase the vacuum degree to be greater than or equal to 0.09MPa, control the temperature in the kettle to 125°C, and recover the thionyl chloride by evaporation. Feed nitrogen into the kettle, keep the vacuum degree greater than or equal to 0.09MPa, control the temperature in the kettle to 135°C, and exhaust the waste gas in the kettle. The reaction solution was cooled to 90°C and transferred to a still. At a vacuum of 0.09MPa, raise the temperature of the still to 110-120°C, collect about 110Kg of the fore distillation, and collect 1770Kg ...

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 a method for preparing aromatic dimethyl chloride, which relates to the technical field of preparation methods of aromatic chloride. The method comprises the following steps of: reacting aromatic dioctyl phthalate with a chlorinating agent to generate the aromatic dimethyl chloride; evaporating the chlorinating agent; exhausting tail gas; and distilling the obtained aromatic dimethyl chloride, wherein the reaction of the aromatic dioctyl phthalate and the chlorinating agent is performed in the presence of a catalyst, namely pyridine or N-methyl pyrolidone; and the chlorinating agent is one or more of chlorine, phosphorus trichloride, phosphorus pentachloride and thionyl chloride. Compared with the prior art, the method for preparing the aromatic dimethyl chloride has the advantages that: the yield and the purity of the aromatic dimethyl chloride are increased, transformation rate is up to 95 percent, and the purity is up to 99.9 percent.

Description

technical field [0001] The invention relates to the technical field of preparation methods of aromatic acid chlorides, in particular to a preparation method of aromatic diacid chlorides. Background technique [0002] Aramid fiber is a military-civilian dual-use special chemical fiber with rapid development and high added value among high-tech fibers. With the continuous expansion of aramid production scale and the rapid development of the aramid industry, as one of the main raw materials for the production of aramid, the market demand for aromatic diacid chloride will further expand. At present, the production methods of aromatic diacid chloride mainly include carboxylic acid acylation method, carboxylate chlorination method and substituted benzene hydrolysis after chlorination. The carboxylic acid acylation method refers to the acylation of aromatic carboxylic acids with a certain acylating agent to directly obtain the product; the carboxylate chlorination method refers to...

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): C07C63/30C07C63/24C07C51/60
Inventor 马海兵吕继平王加强朱荣红
Owner YANTAI TAYHO ADVANCED MATERIALS CO LTD
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