Preparation method of p-aminobenzene sulfonic acid

A technology for p-aminobenzenesulfonic acid and nitrobenzene, which is applied in the preparation of sulfonic acid, the preparation of organic compounds, chemical instruments and methods, etc., can solve the problems of three wastes, complex preparation processes, large energy consumption, etc., and achieve energy saving and emission reduction. efficiency, improving product purity, and the effect of low reaction temperature

Active Publication Date: 2019-07-26
ZHEJIANG LONGSHENG CHEM RES
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] P-aminobenzenesulfonic acid is an important intermediate of reactive dyes. At present, there are two main production methods: one is the high-temperature sulfonation process of aniline and concentrated sulfuric acid, which is divided into liquid phase sulfonation reaction and solid phase sulfonation process. Reaction, the liquid phase sulfonation reaction temperature is generally 180-190 °C, and the solid phase sulfonation reaction temperature is generally 240-260 °C. Both the liquid phase sulfonation reaction and the solid phase sulfonation reaction temperature are high and consume a lot of energy. In addition, high temperature can easily lead to carbonization of the product and affect product quality; the other is the catalytic hydrogenation reduction process of p-nitrobenzenesulfonic acid. The raw materials of phenylsulfonic acid are relatively scarce, and the preparation process is relatively complicated.

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0026] (1) Reductive sulfonation: Add 220g of bottom water to the reactor, then add 130g of 1-methyl-2-pyrrolidone, 130g of ethylene glycol, 49.3g of nitrobenzene, and 59.38g of sodium metabisulfite in sequence, and heat up to 100-105°C Reflux reaction, and then put in 24.8g of sodium metabisulfite every 1h, throw in 4 times in total, react for 1~2h to the end of the reaction after feeding; (2) Desalination: cool the material obtained in step (1) to 0~10°C, Suction filtration after precipitation of inorganic salts, and collect filtrate; (3) Acidification: heat up the filtrate collected in step (2) to 40-50°C, adjust the pH of the filtrate to 1-2 with sulfuric acid, then suction-filter and collect the filter cake and filtrate, The filtrate can be used for the next batch of reduction sulfonation bottom water after being neutralized to neutral, and the filter cake is dried to obtain p-aminobenzenesulfonic acid with an HPLC purity of 99.1% and a mass percentage of 98.9%.

Embodiment 2

[0028] (1) Reductive sulfonation: add 550g bottom water to the reactor, then add 325gN-N dimethylacetamide, 325g ethylene glycol, 124.24g nitrobenzene, 164.21g sodium bisulfite, and heat up to 100~ Reflux reaction at 105°C, and then put in 68.43g of sodium bisulfite every 1h for a total of 4 times, and react for 1-2h to the end of the reaction after feeding; (2) Desalination: cool the material obtained in step (1) to 0 ~10°C, precipitate inorganic salts and press filter to collect the filtrate; (3) Acidification: warm up the filtrate collected in step (2) to 40~50°C, adjust the pH of the filtrate to 1~2 with sulfuric acid, then press filter and collect the filtrate Cake and filtrate, the filtrate can be used for the next batch of reduction sulfonation bottom water after being neutralized to neutral, the filter cake is dried to obtain p-aminobenzenesulfonic acid, the HPLC purity is 99%, and the mass percentage is 98.9%.

Embodiment 3

[0030] (1) Reductive sulfonation: add 110g of bottom water to the reactor, then add 65g of sulfolane, 65g of ethylene glycol, 24.8g of nitrobenzene, and 32.84g of sodium bisulfite in sequence, heat up to 100-105°C for reflux reaction, and then Add 13.69g of sodium metabisulfite every 1h, and throw 4 times in total. After the feeding of sodium bisulfite is completed, react for 1-2h to the end of the reaction; (2) Desalination: cool the material obtained in step (1) to 0-10°C , precipitated inorganic salts, suction filtered, and collected the filtrate; (3) acidification: the filtrate collected in step (2) was heated to 40-50°C, and the pH of the filtrate was adjusted to 1-2 with sulfuric acid, then suction filtered and the filter cake and filtrate were collected. , the filtrate can be used for the next batch of reduction sulfonation bottom water after being neutralized to neutral, and the filter cake is dried to obtain p-aminobenzenesulfonic acid, with an HPLC purity of 99.1% and...

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 preparation method of p-aminobenzene sulfonic acid. The preparation method includes the steps of firstly, performing reduction sulfonation, to be more specific, sequentiallyadding water, a non-proton polar organic solvent, nitrobenzene and a reduction sulfonation agent into a reactor, and heating to 95-130 DEG C to perform reflux reaction; secondly, removing salt, to bemore specific, cooling the material obtained in the first step to 0-20 DEG C to separate out inorganic salt, performing suction filtration or filter pressing, and collecting filtrate 1; thirdly, performing acidification, to be more specific, heating the filtrate 1 obtained in the second step to 30-70 DEG C, adding sulfuric acid to regulate pH to 1-3, performing suction filtration or filter pressing, collecting filtrate 2 and filter cake, and drying the filter cake to obtain the p-aminobenzene sulfonic acid. The method has the advantages that one-step nitrobenzene reduction sulfonation is achieved, the obtained p-aminobenzene sulfonic acid is high in purity, three-waste problems are avoided, and clean production is achieved truly.

Description

[0001] (1) Technical field [0002] The invention relates to a preparation method of p-aminobenzenesulfonic acid. [0003] (2) Background technology [0004] P-aminobenzenesulfonic acid is an important intermediate of reactive dyes. At present, there are two main production methods: one is the high-temperature sulfonation process of aniline and concentrated sulfuric acid, which is divided into liquid phase sulfonation reaction and solid phase sulfonation process. Reaction, the liquid phase sulfonation reaction temperature is generally 180-190 °C, and the solid phase sulfonation reaction temperature is generally 240-260 °C. Both the liquid phase sulfonation reaction and the solid phase sulfonation reaction temperature are high and consume a lot of energy. In addition, high temperature can easily lead to carbonization of the product and affect product quality; the other is the catalytic hydrogenation reduction process of p-nitrobenzenesulfonic acid. The raw materials of phenylsu...

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): C07C303/02C07C309/46C07C303/44
CPCC07C303/02C07C303/44C07C309/46
Inventor 何旭斌王聪徐伟吴建伟张桂香陈浩
Owner ZHEJIANG LONGSHENG CHEM RES
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