Method for coproducing methylbenzoic acid, methyl benzonitrie and phthalonitrile

A technology of methyl benzoic acid and methyl benzonitrile, which is applied in chemical instruments and methods, purification/separation of carboxylic acid nitrile, preparation of carboxylate, etc. The problem of low yield and other problems can be avoided, and the effect of avoiding rectification residue, reducing the amount of three wastes and improving the yield is achieved.

Active Publication Date: 2018-11-23
JIANGXI KEYUAN BIOPHARM
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0020] The purpose of the present invention is to solve the problems in the prior art such as low yield of target product, large amount of solid waste, single product structure, etc., and provide

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 coproducing methylbenzoic acid, methyl benzonitrie and phthalonitrile
  • Method for coproducing methylbenzoic acid, methyl benzonitrie and phthalonitrile
  • Method for coproducing methylbenzoic acid, methyl benzonitrie and phthalonitrile

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0100] Example 1

[0101] The catalyst dissolved in the fresh p-xylene added to the oxidation reactor is cobalt naphthenate, metal phthalocyanine (R 1 =CH 3 CH 2 , R 2 =H, M=Mn), metalloporphyrin (R 1 =R 2 =H, R 3 =CH 3 , M=Cu) mixture, the total concentration is 75ppm, the reaction temperature is 180°C, the reaction pressure is 2MPa, and the oxygen-containing gas is oxygen-enriched air with an oxygen concentration of 24%. The conversion rate of xylene was 42%, and the oxidation reaction solution was obtained. At this time, the mass percentage content of each component in the reaction solution obtained by HPLC analysis is listed in Table 1. In the primary distillation tower, all components whose boiling point is lower than p-toluidine in the oxidation reaction liquid are rectified and separated, and the rectification is stopped when the content of p-toluidine in the still of the initial distillation tower reaches 0.06wt%, The low boiling point component is obtained at ...

Example Embodiment

[0103] Example 2

[0104] The catalyst dissolved in the fresh paraxylene added to the oxidation reactor is MnO 2 and cobalt acetylacetonate, the total concentration is 350ppm, the reaction temperature is 150 ° C, the reaction pressure is 1MPa, the oxygen-containing gas concentration is 21%, the operation process is the same as that of Example 1, the difference is that the conversion rate of p-xylene is controlled to be 50% , the mass percentage content of p-methylbenzyl alcohol in the tower still liquid of the primary steaming tower is controlled to be 0.07%. The mass percentage composition of each component in the reaction solution obtained by HPLC analysis is listed in table 1, and the content of the toluic acid in the obtained preliminary distillation tower tower still liquid, composition and the preliminary distillation tower overhead mixture are listed in the table 2.

[0105] The above-mentioned primary distillation tower still liquid is added to the rectifying tower f...

Example Embodiment

[0106] Example 3

[0107] The catalysts dissolved in the fresh p-xylene added to the oxidation reactor are N-hydroxyphthalimide, cobalt isooctanoate, metal phthalocyanine (R) having the structure of general formula (IV). 1 =OH, R 2 =H, M=Ru) and metalloporphyrins (R 1 =R 3 =H,R 2 =OH, M 1 =M 2 =Mn) mixture, total concentration is 10000ppm, reaction temperature is 116 ℃, reaction pressure is 0.2MPa, oxygen-containing gas is pure oxygen, operation process is identical with embodiment 1, and difference is that the transformation efficiency of p-xylene is controlled as 60%, and the mass percentage content of p-methylbenzyl alcohol in the tower still liquid of the primary steaming tower is controlled to be 0.10%. The mass percentage composition of each component in the reaction solution obtained by HPLC analysis is listed in table 1, and the content of the toluic acid in the obtained preliminary distillation tower tower still liquid, composition and the preliminary distillati...

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 coproducing methylbenzoic acid, methyl benzonitrie and phthalonitrile. The method comprises the following steps: (1) continuously introducing xylol, a catalyst andoxygen-containing gas into an oxidation reactor and reacting to obtain an oxidation reaction solution; (2) conveying the oxidation reaction solution into a primary evaporation tower and carrying outrectification separation; when the content of methylbenzyl alcohol in a tower kettle solution of the primary evaporation tower reaches 0.01 to 0.15 weight percent, stopping rectification, so as to obtain a low-boiling-point component and the tower kettle solution of the primary evaporation tower; (3) conveying the tower kettle solution of the primary evaporation tower into a rectification tower and carrying out rectification; when the content of the methylbenzoic acid in a tower kettle solution of the rectification tower reaches 30 to 90 weight percent, stopping rectification, so as to obtaina methylbenzoic acid product and the tower kettle solution of the rectification tower; (4) mixing the tower kettle solution of the rectification tower and ammonia to obtain a nitrile-containing reaction solution; (5) carrying out rectification separation on the nitrile-containing reaction solution to obtain methyl benzonitrie and phthalonitrile products. The method disclosed by the invention has the advantages of simple technology, few equipment investment, greenness and environment protection and good comprehensive economic benefits.

Description

technical field [0001] The invention relates to the technical field of fine chemicals, in particular to a method for co-producing methylbenzoic acid, methylbenzonitrile and phthalonitrile. Background technique [0002] Tolunitrile includes m-methylbenzonitrile, p-methylbenzonitrile and o-methylbenzonitrile, all of which are widely used in medicine, pesticides, photosensitive materials and dye intermediates. The existing production of methyl benzonitrile mainly uses high-purity methyl benzoic acid as a raw material, and after preparing methyl benzonitrile through amination and dehydration reactions, the product is refined and purified by rectification. Due to the high boiling point of the product, more rectification residues will be produced in the rectification process, resulting in a large amount of solid waste residue in the rectification column and low product yield. Generally, the molar yield based on toluic acid is not more than 85%. Another production method of methy...

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
IPC IPC(8): C07C51/265C07C51/44C07C63/04C07C253/22C07C253/34C07C255/50C07C255/51
CPCC07C51/265C07C51/44C07C253/22C07C253/34C07C63/04C07C255/50C07C255/51
Inventor 王勤波熊振华宗匡曹金辉曾鹏
Owner JIANGXI KEYUAN BIOPHARM
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