Method for separating high-purity phenazine from chemical product production waste

Abstract

The invention provides a method for separating high-purity phenazine from a waste material generated in chemical product production. A light component removing tower and a heavy component removing tower are adopted, wherein the light component removing tower is provided with a tower top condenser and a tower kettle re-boiler; the heavy component removing tower is provided with a tower top condenser and a tower kettle re-boiler. The method is characterized by comprising the following steps: allowing a phenazine-containing raw material liquid to enter the middle part of the light component removing tower after heat is exchanged by a raw material preheater; removing phenylamine and azobenzene from the tower top to obtain the phenylamine of which the purity is larger than 97% for recycle; allowing a material flow of the light component removing tower to enter the middle part of the heavy component removing tower; removing a 4-amino diphenylamine heavy component from the tower bottom to obtain 4-amino diphenylamine of which the purity is larger than 99%, and directly taking the 4-amino diphenylamine as a product or using the 4-amino diphenylamine in the next stage of refining; and obtaining a phenazine product of which the purity is larger than 99.5% at the top of the heavy component removing tower. According to the method disclosed by the invention, continuous operation is adopted, and a thermal-coupled rectification separation process is adopted during the overall method, so the energy consumption of a system is reduced. According to the method disclosed by the invention, the two towers adopt decompression distillation and are packed towers, so the separation efficiency is higher, and the pressure reduction and tower kettle temperature are reduced as well.

Description

technical field [0001] The invention relates to a method for separating and purifying phenazine, in particular to a method for separating high-purity phenazine from chemical product production waste, and belongs to the field of phenazine separation and purification. Background technique [0002] Phenazine, also known as diazepine, English name: Phenazine, molecular formula C12H8N2, is colorless or light yellow needle-like crystal, almost insoluble in water, slightly soluble in ethanol, ether and benzene, soluble in inorganic acid to yellow to red solution. Phenazines have a certain special status in the field of organic chemistry. The earliest applications of phenazine and its derivatives were dyes, and then they were found to be biologically active and could be used as fungicides. In recent years, phenazines have been widely used in the fields of medicine, pesticides, chromophores, conductors and battery materials. [0003] Phenazine is mainly prepared by the ring-closin...

AI Technical Summary

Problems solved by technology

[0003] Phenazine is mainly prepared by 2-amino or nitrodiphenylamine ring-closing reaction, o-phenylenediamine and catechol condensation reaction, etc. The synthesis process is complex, the yield is medium, and the cost is high

In the process of producing 4-aminodiphenylamine with nitrobenzene and aniline as raw materials, the by-product phenazine will be produced, which cannot be removed during the separation process, and forms a waste mixture with 4-aminodiphenylamine, aniline, azobenzene, etc. , direct discharge will cause environmental pollution, and incineration will cause a lot of waste

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