Method for extracting indole from methyl naphthalene fraction

A technology of methylnaphthalene fraction and indole, which is applied in the field of indole extraction, can solve the problems of low quality and low yield of indole oil, and achieve the effects of high yield, short process and less investment in equipment

Inactive Publication Date: 2015-09-02
LIAONING INST OF SCI & TECH
View PDF9 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although the indole extraction rate of the "acid polymerization method" is high, which creates convenient conditions f

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 extracting indole from methyl naphthalene fraction

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] Add the methylnaphthalene fraction containing 3% indole to the scrubber, add sulfuric acid solution with a concentration of 50% according to the ratio of mass ratio 1:0.1, heat up to 60°C under stirring conditions, keep it warm for 90min, and let it stand for 60min before releasing The quinoline base solution of indole oligomers is dissolved in the lower layer, and finally the washed methylnaphthalene fraction is released, which basically does not contain quinoline homologues and indole. The solution in the lower layer was frozen to -5°C, and then centrifuged to obtain khaki granular indole oligomer salt, poured into 5% sodium hydroxide solution under the condition of centrifuge rotation until the centrifuge was alkaline, and then added the solid material In the reaction kettle with a reflux condenser, add the solvent crude dimethylethylbenzene in a mass ratio of 1:0.5, raise the temperature to 140°C under stirring conditions, keep the temperature for 90min, and then gra...

Embodiment 2

[0031] Add the methylnaphthalene fraction containing 4% indole to the scrubber, add the sulfuric acid solution with a concentration of 55% according to the mass ratio of 1:0.15, raise the temperature to 70°C under stirring, keep it warm for 90min, and let it stand for 60min, then release A quinoline base solution of indole oligomers is dissolved in the lower layer, and then the washed methylnaphthalene fraction is released, which basically does not contain quinoline homologues and indole. The solution in the lower layer was frozen to -3°C, and then centrifuged to obtain khaki granular indole oligomer salt, poured into 5% sodium hydroxide solution under the condition of centrifuge rotation until the centrifuge was alkaline, and then added the solid material In the reaction kettle with a reflux condenser, add the crude dimethylethylbenzene as a solvent in a mass ratio of 1:0.5, heat up to 150°C under stirring conditions, keep the temperature for 90min, and then gradually increase...

Embodiment 3

[0033]Add the methyl naphthalene fraction containing 5% indole to the scrubber, add the sulfuric acid solution with a concentration of 60% according to the mass ratio of 1:0.2, raise the temperature to 80°C under stirring, keep it warm for 90min, and let it stand for 60min, then release The quinoline base solution of indole oligomers is dissolved in the lower layer, and finally the washed methylnaphthalene fraction is released, which basically does not contain quinoline homologues and indole. The solution in the lower layer was frozen to -2°C, and then centrifuged to obtain khaki granular indole oligomer salt, poured into 5% sodium hydroxide solution under the condition of centrifuge rotation until the centrifuge was alkaline, and then added the solid material In the reaction kettle with a reflux condenser, add the crude dimethylethylbenzene as a solvent in a mass ratio of 1:0.5, heat up to 150°C under agitation, keep the temperature for 90min, and then gradually increase the v...

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 relates to a method for extracting indole from a methyl naphthalene fraction. The method comprises the following steps: with the methyl naphthalene fraction in coal tar washing oil as a raw material, adding 50%-60% sulfuric acid solution, heating, reacting, and standing and layering, so as to obtain a quinolinium-based solution dissolved with an indole oligomer; freezing, crystallizing, and centrifugally separating to obtain an indole oligomer salt of earthy yellow particles; washing with diluted alkali; and adding a solvent, heating and depolymerizing to obtain crude indole of which the content is greater than 90% and the yield is 90%. The method aims at extraction of the indole from the methyl naphthalene fraction; meanwhile, production of quinoline and beta-methylnaphthalene are taken into account; and the method has the advantages of being short in flow, simple to operate, good in product quality, high in yield and small in environmental burden.

Description

technical field [0001] The indole in the invention is a deep-processed product of coal tar, belongs to the technical field of chemical industry, in particular a method for extracting indole from the methylnaphthalene fraction of coal tar washing oil. Background technique [0002] Indole is an important component in coal tar and has a wide range of uses. Indole can be used as a flavor retaining agent, synthesize tryptophan used to promote animal growth, and can also be used to synthesize plant growth hormones β-indole acetic acid, β-indole propionic acid, etc. [0003] The methylnaphthalene fraction contains indole, and also contains important components such as β-methylnaphthalene, α-methylnaphthalene, quinoline, and isoquinoline. Although indole (boiling point 253°C) is similar to β-methylnaphthalene ( The boiling point is 241°C) and the boiling point is quite different, but it can form an azeotropic mixture with β-methylnaphthalene, so indole should be extracted before re...

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): C07D209/06
CPCC07D209/06
Inventor 鄂永胜鄢景森刘志君周嘉圣
Owner LIAONING INST OF SCI & TECH
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