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Pyrocatechin and hydroquinone production process

A technology for hydroquinone and catechol, applied in the field of catechol and hydroquinone production technology, can solve the problems of huge phenol separation work, high energy consumption and high cost, and achieves easy industrial automation and large scale. The effect of large-scale production, easy control of process conditions and low production cost

Inactive Publication Date: 2007-05-16
王在军
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0011] The hydrolysis of o-chlorophenol produces a large amount of waste water, heavy pollution, and low yield. The oxidation of aniline produces a large amount of waste water and waste residue, and the cost is also high. For the oxidation of phenol with hydrogen peroxide, 50-70% hydrogen peroxide is used to ensure the safety of production. , the requirements on equipment are very high, the investment is large, and, because of the low conversion rate per pass, the separation of phenol, catechol, and hydroquinone is very huge, which will inevitably lead to large energy consumption

Method used

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  • Pyrocatechin and hydroquinone production process
  • Pyrocatechin and hydroquinone production process
  • Pyrocatechin and hydroquinone production process

Examples

Experimental program
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Effect test

Embodiment 1

[0044] Preparation of o-nitrophenol: Add 150 parts of Zhebai sodium hydroxide to the autoclave, add 250 parts of o-nitrochlorobenzene with a concentration of 80g / L sodium hydroxide aqueous solution, heat to 140-150°C, and the pressure is about 0.45MPa , keep warm for 2 hours, then raise the temperature to material 155-160°C, pressure about 0.54, keep warm for 3 hours. Cool down to about 120°C, press the material into a reaction kettle lined with acid-resistant ceramic tiles and equipped with titanium cooling coils and titanium stirring, neutralize with 30% hydrochloric acid until the pH is 1-2, cool down to 30°C, and filter with suction to obtain 210 parts of o-nitrophenol tidal products, the content is about 92%, and the yield is 90-95%. The parts of the raw materials are all parts by weight.

[0045] Preparation of o-aminophenol: 300 parts of o-nitrophenol, 1000 parts of 95% ethanol, 9 parts of activated nickel catalyst, sealed reaction kettle, heated to about 80 ° C, under...

Embodiment 2

[0048] With embodiment 1, difference is:

[0049]Preparation of catechol: 100 parts of o-aminophenol, 92 parts of 98% sulfuric acid, and 808 parts of water are placed in a zirconium reactor, heated to 235°C, controlled at 235-240°C for 3 hours, cooled to 50°C, filtered , the filtrate was extracted with butyl acetate, the butyl acetate was recovered, and the residue was distilled under reduced pressure at 25 mmHg to obtain 88 parts of pure catechol with a content of 99.7% and a yield of 85-90%. The parts of the raw materials are all parts by weight.

Embodiment 3

[0051] With embodiment 1, difference is:

[0052] Preparation of catechol: 108 parts of o-aminophenol, 230 parts of ammonium bisulfate, and 1700 parts of water are placed in a zirconium reactor, heated to 240°C, controlled at 240-242°C for 4 hours, and cooled to 40-50°C , filtered, the filtrate was extracted with n-butyl ether, n-butyl ether was recovered, and the residue was distilled under reduced pressure at 25 mmHg to obtain pure catechol with a content of 99.8 / 5 and a yield of 99.1%. The parts of the raw materials are all parts by weight.

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Abstract

The invention discloses a cleaning preparing technique to manufacture catechol and hydroquinone, which comprises the following steps: adopting o (p-)-nitrochlorobenzene as raw material; pressurizing the sodium hydroxide to obtain o (p-)-nitrophenol through hydrolyzing; hydrogenating under nickel catalyst; producing the product under acid catalyst in the water dielectric; avoiding high-salt and nitro waste water effectively as well as high-density hydrogen dioxide solution.

Description

technical field [0001] The invention belongs to the field of fine chemical industry and relates to a production process of fine chemical intermediates, in particular to a clean and pollution-free production process of catechol and hydroquinone. Background technique [0002] Catechol is an important intermediate for the production of high-efficiency new carbamate pesticides carbofuran (carbofuran), propoxur, and diethofencarb, and is also an important raw material for the production of spices piperonal and vanillin. Catechol is also in demand in the fields of agents, photosensitive materials, medicines, dyes, etc. [0003] Hydroquinone is mainly used in the synthesis of photosensitive materials, anthraquinone, fertilizer additives, polymerization inhibitors for synthetic materials, antioxidants and rubber additives. [0004] At present, the main production processes of catechol and hydroquinone are as follows: [0005] 1. Hydrolysis of o-chlorophenol to produce catechol: ...

Claims

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Application Information

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IPC IPC(8): C07C39/08C07C37/02C07C37/05
Inventor 王在军石艳
Owner 王在军
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