Method for separating catechol/hydroquinone from phenol hydroxylation reaction solution

A technology for hydroxylation of phenol and hydroquinone, applied in chemical instruments and methods, preparation of organic compounds, organic chemistry, etc., can solve problems such as high energy consumption, large thermal loss of dihydric phenol, and low separation yield , to achieve the effect of reducing energy consumption, solving the problem of large thermal loss, and reducing the number of theoretical boards

Active Publication Date: 2008-07-23
SHANGHAI HUAYI NEW MATERIAL
View PDF3 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At the same time, it solves technical problems such as large heat-sensitive loss of dihydric phenol, low separation yield, and high energy consumption.

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 separating catechol/hydroquinone from phenol hydroxylation reaction solution
  • Method for separating catechol/hydroquinone from phenol hydroxylation reaction solution

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] The mass composition is 37.8% water, 52.8% phenol, 4.5% catechol, 2.7% hydroquinone, 2.2% tar, and the phenol hydroxylation reaction solution is sent to the dehydration tower [2] with a flow rate of 200kg / h, and the dehydration tower [2] Normal pressure operation, reflux ratio 0.2, tower kettle temperature 185~190℃. An aqueous solution [3] with a mass percent content of 10.4% phenol is obtained from the top of the tower, wherein 38 mass percent phenol is sent to the extraction tower [4] to recover phenol, and the rest is recycled to the reaction system for reuse. The output of the dehydration tower [2] is sent to the dephenol main tower [8]. The operating pressure of the dephenol main tower [8] is 5kPa, the reflux ratio is 0.5, and the temperature of the tower kettle is 150-155°C. The output from the bottom of the dephenol main tower [8] is sent to the dephenol sub tower [9]. The operating pressure of the dephenol sub-column [9] is 5kPa, the reflux ratio is 4, and the...

Embodiment 2

[0039] The phenol hydroxylation reaction liquid that mass content is 57.8% water, 32.8% phenol, 4.5% pyrocatechol, 2.7% hydroquinone, 2.2% tar is sent into dehydration tower [2] with 200kg / h, dehydration tower [2] 2] Normal pressure operation, reflux ratio 0.5, tower kettle temperature 185-190°C. An aqueous solution fraction [3] with a mass percentage of 10.0% phenol is obtained from the top of the tower, wherein 38% phenol is sent to the extraction tower [4] to recover phenol, and the rest of the cyclic reaction system is reused.

[0040]The output of the dehydration tower [2] is sent to the dephenol main tower [8]. The operating pressure of the dephenol main tower [8] is 5kPa, the reflux ratio is 0.5, and the temperature of the tower kettle is 150-155°C. The output from the bottom of the dephenol main tower [8] is sent to the dephenol sub tower [9]. The operating pressure of the dephenol sub-column [9] is 5kPa, the reflux ratio is 4, and the temperature of the column botto...

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 of separating catechol / hydroquinone in phenol hydroxylation reaction solution, which is characterized in that: phenol and hydrogen peroxide are reacted under catalyst action to produce reaction solution comprising water, phenol, catechol, hydroquinone and tar; vacuum rectification dehydration, de-phenol, catechol separating, hydroquinone separating and tar removing are made upon the reaction solution to prepare the catechol and the hydroquinone product; thermal medium oil independent circulation stepwise condensation / heat mode is adopted for the distillation system separating the catechol and the hydroquinone; vertical sieve plate is adopted for stripping section of the distillation tower; high-efficiency structured packing is adopted for the distillation section; embedded type structure in the tower is adopted for the condenser and the reboiler of the distillation tower. The method of separating catechol / hydroquinone in phenol hydroxylation reaction solution has the advantages of solving the problems of difficultly liquefying the catechol and the hydroquinone for the condenser at the top part of the distillation tower and easily causing material condensing or gasifying due to small difference value between the boiling point and the freezing point during vacuum rectifying for the catechol and the hydroquinone, prolonging production period, lowering unit consumption of product and reaching more than 99% for product purity of the catechol and the hydroquinone.

Description

technical field [0001] The invention relates to a method for separating o- / hydroquinone in a phenol hydroxylation reaction solution. Specifically, the present invention includes a method for preparing catechol and hydroquinone by separating the reaction solution generated by the hydroxylation reaction of phenol and hydrogen peroxide in the presence of a catalyst, and the method used for separating ortho / hydroquinone Heat medium oil independent circulation fractional condensation / heating rectification system and rectification tower with condenser and reboiler embedded in the tower. Background technique [0002] Catechol and hydroquinone are two important fine chemical products with a wide range of applications. Catechol is widely used in pesticides, medicines, spices, rubber, dyes, photosensitive materials and other industries; hydroquinone is mainly used in the synthesis of photosensitive materials, fertilizer additives, anthraquinone dyes, azo dyes, rubber additives, etc. ...

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 Applications(China)
IPC IPC(8): C07C39/08C07C37/68C07C37/60
Inventor 唐勇崔曜张春雷马建学邵敬铭
Owner SHANGHAI HUAYI NEW MATERIAL
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