Preparation process for sodium 1-amino-4-bromoanthraquinone-2-sulfonate

Abstract

The invention discloses a preparation process for sodium 1-amino-4-bromoanthraquinone-2-sulfonate. The preparation process comprises the following steps: (1) sulfonation: with 1-aminoanthraquinone as a raw material, copper sulfate as a catalyst and dichloroethane as a solvent, carrying out dehydration, then adding chlorosulfonic acid drop by drop for a sulfonation reaction, adding 98% concentrated sulfuric acid after completion of the reaction, extracting 1-aminoanthraquinone-2-sulfonic acid out, allowing 1-aminoanthraquinone-2-sulfonic acid to enter the concentrated sulfuric acid, separating out an acid phase at a lower layer and subjecting the acid phase to a subsequent reaction; (2) bromination: adding bromine into the concentrated sulfuric acid solution of 1-aminoanthraquinone-2-sulfonic acid drop by drop for a reaction so as to obtain the concentrated sulfuric acid solution of bromoamine acid; (3) dilution: adding water into the concentrated sulfuric acid solution of bromoamine acid for dilution and successively carrying out cooling, crystallization and filtering so as to obtain bromoamine acid; and (4) salt formation: adding water to dissolve bromoamine acid and adding sodium sulfite to obtain bromoamine acid sodium salt. The preparation process provided by the invention can reduce energy consumption during solvent recovery; the utilization rate of bromine in bromination is high; sodium sulfite is used for salt formation, so the amount of impurities is reduced; and product quality is high.

Description

technical field [0001] The invention belongs to the field of chemical industry, in particular to a preparation process of sodium 1-amino-4-bromoanthraquinone-2-sulfonate. Background technique [0002] 1-Amino-4-bromoanthraquinone-2-sodium sulfonate, commonly known as sodium bromide, is an important intermediate with a wide range of uses in the dye manufacturing industry. It is widely used in the preparation of high-grade active, acidic, dispersing Anthraquinone-like dyes. [0003] The existing production method of sodium bromide is to use 1-aminoanthraquinone as a raw material, and it is made through sulfonation, bromination, salt formation, refining and other technological steps. Among them, the sulfonation process can be divided into direct sulfonation and solvent sulfonation processes. [0004] In the existing production process, the direct sulfonation process has many side reactions, low yield, and produces a large amount of waste sulfuric acid that is difficult to han...

AI Technical Summary

Problems solved by technology

[0004] In the existing production process, the direct sulfonation process has many side reactions and low yield, and will produce a large amount of waste sulfuric acid that is difficult to handle

Chinese patent CN102617412.A uses the solvent method sulfonation process, which has the following disadvantages: 1. Although the o-dichlorobenzene solvent can be recycled, it will inevitably increase the impurities in the solvent after repeated use, which will affect the sodium bromide product. 2. Due to the high boiling point of o-dichlorobenzene, more energy will be consumed in the dehydration process and solvent distillation process; 3. The bromination process generally carries out the bromination reaction in 8% to 10% sulfuric acid concentration. During the bromination reaction, hydrogen bromide will be produced at the same time, and the produced hydrogen bromide needs to be absorbed by lye and then oxidized by chlorine gas to recover bromine and improve the utilization rate of bromine