Method for preparing methyl acetoacetate by using novel composite catalyst

A technology of methyl acetoacetate and composite catalyst is applied in chemical instruments and methods, preparation of organic compounds, organic compounds/hydrides/coordination complex catalysts, etc., and can solve the problem of low product yield, crude methyl acetoacetate, etc. problems such as low content, to achieve the effects of improving distillation yield, complete esterification reaction, and reducing energy consumption

Active Publication Date: 2012-02-29
安徽天成新材料有限公司
View PDF0 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The thick methyl acetoacetate content that this method produces is low (only 97.42%), and product yield is low (only 96.84%)

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 methyl acetoacetate by using novel composite catalyst
  • Method for preparing methyl acetoacetate by using novel composite catalyst

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach

[0013] Add 1.2 tons of methanol with a purity of 99.9% into a 5000L enamel kettle, add 1.5kg of triethylenediamine under stirring, add 3.0 tons of diketene with a content ≥ 97.5%, dropwise, keep it at 110°C for 1 hour, cool down to 40°C, add 3 Concentrated sulfuric acid with a kilogram content ≥ 98% is used as a catalyst, heat-preserved for half an hour, and the resulting liquid is filtered to obtain crude diethyl methyl ester.

[0014] The crude diethyl methyl ester enters the low boiling tower after being preheated by diethyl methyl steam in the high boiling tower, and the low boiling matter is removed. About 70% of the methyl acetoacetate in the low boiling matter is recovered and enters the rectifying tower, and the acetic acid, Methanol and other substances are incinerated to generate carbon dioxide and water, and there is no pollution emission. The reaction liquid that removes the low boilers flows into the high boiling tower, the rectification residue is released from t...

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 methyl acetoacetate by using complex catalyst, which comprises the following steps: carrying out esterification reaction of methanol and diketene to generate crude methyl acetoacetate, wherein two different catalysts are added in the different stages of the esterification reaction; triethylenediamine catalyst is added before the esterification reaction; and diketene can be added directly dropwise without being heated by vapor, thereby overcoming the disadvantage that diketene is added dropwise after heating methanol to the boiling point in the conventional process and reducing the energy consumption; and cooling the generated liquid to 40 DEG C after the reaction, adding concentrated sulfur acid catalyst, keeping the temperature for half an hour, filtering, continuously rectifying the filtrate, and separating to obtain fine methyl acetoacetate with the content larger than 99%. Compared with the conventional intermittent rectification method, the continuous rectification method has greatly improved throughput and more convenient operation.

Description

technical field [0001] The invention relates to a method for preparing methyl acetoacetate using a novel composite catalyst, which belongs to the technical field of chemical industry. Background technique [0002] According to "Fine Organic Chemical Materials and Intermediates Handbook" (Chemical Industry Press, edited by Xu Kexun, March 1999), the reaction generation principle of methyl acetoacetate is: That is, use concentrated sulfuric acid as a catalyst, raise the temperature of methanol to boiling, add diketene dropwise, remove the low boilers in the reaction kettle, then stop the reception of the previous fraction, and start to receive the main fraction, refined methyl acetoacetate, until it is removed. . The content of crude methyl acetoacetate produced by the method is low (only 97.42%), and the product yield is low (only 96.84%). Contents of the invention [0003] In order to overcome the deficiencies in the prior art, the object of the present invention is 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 Patents(China)
IPC IPC(8): C07C69/72C07C67/08B01J31/02B01J27/04
Inventor 陈正荣陈敏陈飞崔惠忠
Owner 安徽天成新材料有限公司
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