Unlock instant, AI-driven research and patent intelligence for your innovation.

Process for preparing malononitrile

A malononitrile and flask technology is applied in the dehydration preparation of carboxylic acid amides, organic chemistry and other directions, which can solve the problems of short reaction period, low yield, unstable formation, etc., and achieve good quality, obvious economic and social benefits, and products. high yield effect

Active Publication Date: 2016-01-20
JIANGSU KUAIDA AGROCHEM
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method has a short reaction cycle, but because the by-products generated in the reaction are low-phosphate and easy to solidify, it often results in unstable formation and low yield
[0003] Chinese patent CN103044286A discloses a kind of production method of malononitrile, but its yield is only 50~70%

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
  • Process for preparing malononitrile
  • Process for preparing malononitrile

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] Put 200g of cyanoacetamide, 470g of toluene, and 6g of tetrabutylammonium bromide into a 1000ml flask, pass through about 270g of phosgene, and reflux at 50-65°C for 5 hours. The solution was reserved for the next batch, and the lower layer material was distilled under negative pressure to obtain 126.7 g of malononitrile. Product yield: 80.0%, content: 99.3%.

Embodiment 2

[0021] Embodiment 2: drop into cyanoacetamide 200g in the 1000ml flask, reclaim mechanical toluene 505g in adding example (1), tetrabutyl ammonium bromide 2g, pass into and reclaim about 290g of phosgene (containing 5% hydrogen chloride), at 70~ Reflux reaction at 90°C for 5 hours, the reaction material was transparent visually, cooled and separated, the upper toluene solution was reserved for the next batch, and the lower material was distilled under negative pressure to obtain 141.0 g of the product malononitrile. The product yield is 89%, and the content is 99.2%.

Embodiment 3

[0022] Embodiment 3: drop into cyanoacetamide 200g in the 1000ml flask, toluene 470g, benzyltriethylamine chloride 6g, pass into about 270g of phosgene, reflux reaction at 70~90 ℃ for 5 hours, visual inspection reaction material is transparent, cooling, Layered, the toluene solution in the upper layer was reserved for the next batch, and the material in the lower layer was distilled under negative pressure to obtain 125.7 g of the product malononitrile. Product yield: 81.0%, content: 99.0%.

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 production method for synthesizing malononitrile. According to the production method, carbonyl chloride or recovered phosgene containing 5% of hydrogen chloride is taken as a dehydration reagent and reacts with cyanoacetamide to synthesize malononitrile; the reaction is performed in the presence of a medium solvent and a catalyst. The production method for synthesizing malononitrile has the advantages that phosgene is taken as the dehydration reagent and carbon dioxide and hydrogen chloride are formed at last without wastewater, the product is high in yield and good in quality, and obvious economic and social benefit are produced. Especially, when tetrabutylammonium bromide or benzyl triethyl ammonium chloride is taken as the catalyst, the yield is above 80%.

Description

technical field [0001] The present invention relates to a kind of preparation method of malononitrile. Background technique [0002] Malononitrile is a basic chemical raw material, which is widely used in pharmaceutical, pesticide and dye industries. According to data, at present, the production process of malononitrile in this industry includes: (1) using cyanoacetamide as raw material, dichloroethane as solvent medium, dehydrochlorination with phosphorus oxychloride under the action of catalyst to form phosphoric acid Or metaphosphoric acid and malononitrile, and the liquid phase is separated by distillation to obtain malononitrile. The yield of the product obtained by this process route is low, the three wastes are many, and it is difficult to handle. (2) Use cyanoacetamide as the raw material, mix it with phosphorus oxychloride evenly, and then heat it. When the mixture starts to boil, distill out phosphorus oxychloride under reduced pressure, and then distill out malo...

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 Patents(China)
IPC IPC(8): C07C255/04C07C253/20
Inventor 钱圣利韩邦友李海燕徐相俊孙美霞李强高国庆
Owner JIANGSU KUAIDA AGROCHEM