Method for producing p-p-phenylene diamine by p-nitroaniline hydrogenation

Abstract

The invention provides a novel process for synthesizing p-phenylene diamine which comprises, using a catalyst and a solvent, producing p-p-phenylene diamine by p-nitroaniline hydrogenation, disintegrating catalyst after end of reaction, and obtaining p-phenylene through disintegrating solvent from the solution by crystallization or distillation.

Description

technical field [0001] The invention belongs to the field of fine chemicals and relates to a method for producing p-phenylenediamine by hydrogenating p-nitroaniline. The International Patent Classification belongs to C07B 43 / 04. Background technique [0002] p-Phenylenediamine is an important organic chemical raw material, which is generally used in the production of dyes, rubber antioxidants, etc. There are two traditional production methods, one is the iron powder reduction method, which uses iron powder and hydrochloric acid to reduce p-phenylenediamine Aniline; Another method is alkali sulfide reduction method, which uses alkali sulfide to reduce p-nitroaniline. These two methods all produce a large amount of sewage and sludge, serious environmental pollution, and the cost of sewage treatment is very high, and the product yield is low, generally about 80%, so this production method has high cost and is harmful to the environment. [0003] The purpose of the present inv...

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Problems solved by technology

These two methods all produce a large amount of sewage and sludge, serious environmental pollution, and the cost of sewage treatment is very high, and the product yield is low, generally about 80%, so the production method is costly and harmful to the environment.