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Aminophenol is an important organic chemical raw materials and intermediates in the petrochemical industry, pesticides, pharmaceuticals, dyes and other fields of application is very extensive. So far, the development of a variety of synthetic aminophenol process, mainly nitrobenzene, resorcinol ammonia solution, electrolysis nitrophenol, aniline hydroxylation method hydrochloric acid and m-phenylenediamine method , but most of them were behind the existence of technology, serious pollution, high cost, high yield and selectivity and a higher requirement on equipment issues. This paper presents phenylenediamine sulfate hydrolysis aminophenol new technology, and this in a systematic study, focused on the separation of the hydrolyzate and m-phenylenediamine hydrolysis reaction of two parts, contents and results are as follows: Given phenylenediamine sulfate hydrolysis process aminophenol hydrolyzate consists primarily of m-phenylenediamine, m-aminophenol and resorcinol three components, this paper on the three components were mixed aqueous extraction of , by contrast, preferred extractant screening isoamyl acetate and n-butyl acetate, and to determine the appropriate extraction conditions. Respectively, iso-amyl acetate and n-butyl acetate as the extraction agent, m-aminophenol, resorcinol and phenylenediamine solution of the one-component solvent extraction liquid phase equilibrium studies. The results showed that butyl acetate than isoamyl acetate, extraction and separation of the three components is more favorable. In order to n-butyl acetate as extractant conditions, were obtained by acidic Mixtures of resorcinol, m-phenylenediamine and lye Mixtures Mixtures aminophenol brine phase equilibrium data correlation. Through single factor and orthogonal experiments, the effects of reaction time, temperature, material ratio and acid concentration on the hydrolysis reaction of m-phenylenediamine influence to determine the optimum process conditions were: acid concentration of 22%, the reaction temperature of 200 ℃, m-phenylenediamine and concentrated sulfuric acid molar ratio of 1:1.98, and the reaction time was 6 h. In this condition, the conversion of phenylenediamine rate reached 81.19%, m-aminophenol yield of 56.34%, 69.38% selectivity to by-products of resorcinol yield was 24.13%. Of kinetic experiments were obtained at 190 ℃, 200 ℃, 210 ℃ temperature conditions phenylenediamine hydrolysis reaction rate equation. In this paper, sulfuric acid hydrolysis aminophenol new process for solvent extraction separation hydrolyzate phase equilibrium study of the system to optimize the hydrolysis conditions, arrived at a different temperature conditions phenylenediamine hydrolysis reaction rate equation, for which no literature reports, in-depth study for the technology foundation.
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