Method of separating and purifying o/p-dihydroxy benzene prepared by phenol hydroxylation

A technology for hydroxylation of phenol and hydroquinone, applied in chemical instruments and methods, preparation of organic compounds, organic chemistry, etc., can solve the problems of increasing energy consumption for de-catechol, equipment manufacturing, and maintenance costs, and achieves The effect of energy consumption reduction, carbonization prevention, and good fluidity

Inactive Publication Date: 2007-10-17
SHANGHAI HUAYI ACRYLIC-ACID CO LTD
View PDF2 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In this process flow, the secondary dephenolization is placed before detarring. Although the energy consumption of the process is lower than that of the Rhone Planck Company, it still increases the energy consumption of decatechol compared with the final detarring process; the dehydration tower Using decompression operation, the tower diameter is several times larger than that of the ...

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 of separating and purifying o/p-dihydroxy benzene prepared by phenol hydroxylation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] The raw material liquid is sent into the dehydration tower 2 at 211.9kg / h, and the composition of the raw material is shown in Table 1.

[0025]The dehydration tower 2 is operated under normal pressure, the reflux ratio is 0.2, and the temperature of the tower kettle is 185-190°C. An aqueous solution 3 containing 10.4% phenol is obtained at the top of the tower, 38% of which is sent to the extraction tower 4 to recover phenol 7, and the rest is reused in the circulating reaction system. The composition of the output from the tower kettle is shown in Table 2.

[0026] composition

water

phenol

Catechol

Quinol

tar

Content / %

37.8

52.8

4.5

2.7

2.2

[0027] composition

water

phenol

Catechol

Quinol

tar

Content / %

0.8

83.1

7.7

4.6

3.8

[0028] The 3 fractions of the phenol aqueous solution are sent to the rotary disk extrac...

Embodiment 2

[0039] The raw material liquid is sent into the dehydration tower 2 at 211.9kg / h, and the composition of the raw material is shown in Table 7.

[0040] composition

water

phenol

Catechol

Quinol

tar

Content / %

57.8

32.8

4.5

2.7

2.2

[0041] composition

water

phenol

Catechol

Quinol

tar

Content / %

0.3

73.6

12.5

7.5

6.1

[0042] The dehydration tower 2 is operated under normal pressure, the reflux ratio is 0.5, and the temperature of the tower kettle is 185-190°C. A 10.0% aqueous solution containing phenol fraction is obtained at the top of the tower, 38% of which is sent to the extraction tower 4 to recover phenol, and the rest is reused in the circulating reaction system. The composition of the output from the tower kettle is shown in Table 8.

[0043] The phenol aqueous solution fraction is sent to the rotary disk extraction ...

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 separation and purification method of catechol and hydroquinone prepared by hydroxylation reaction of phenyl hydrate with hydrogen peroxide, wherein the product consists of water, phenyl hydrate, pyrocatechol, p-dihydroxy benzene and tar. The separation and purification method of present invention principally includes the following steps: transmitting resultant of reaction into normal pressure leading tower, and water solution containing phenols on tower top partially entering extraction column for reclaiming phenyl hydrate; the liquid of leading tower passing though de-phenol main tower, de-phenol auxiliary tower in sequence and tower top fraction of auxiliary tower returning main tower; the liquid of de-phenol auxiliary tower passing through pyrocatechol fractionating tower and p-dihydroxy benzene fractionating tower and then obtaining producers of pyrocatechol and p-dihydroxy benzene whose purity is more than 99% in sequence, at last the tar discharged from decoking tower.

Description

technical field [0001] The present invention relates to the separation and purification method of the reaction product of o- / hydroquinone prepared by hydroxylation of phenol and hydrogen peroxide, specifically dehydrating the phenol hydroxylation reaction solution, extracting phenol, rectifying and separating catechol and hydroquinone A series of separation processes such as diphenol and tar removal can achieve the purpose of recovering unreacted raw material phenol, and separating and purifying catechol and hydroquinone products. technical background [0002] Catechol and hydroquinone are two important fine chemical products with a wide range of applications. Catechol, also known as catechol, is a basic organic raw material or intermediate in industries such as pesticides, medicines, spices, rubber, dyes, and photosensitive materials. In the pesticide industry, it is an important intermediate for the production of carbofuran, ethylfencarb, and propoxur; it is used in the m...

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): C07C39/08C07C37/74C07C37/80
Inventor 崔曜许宁张春雷唐勇马建学邵敬铭
Owner SHANGHAI HUAYI ACRYLIC-ACID CO LTD
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