Method for preparing m-aminophenol through pressurization alkaline hydrolysis of m-chloroaniline

Abstract

A method for preparing m-aminophenol through pressurization alkaline hydrolysis of m-chloroaniline relates to the technical field of the chemical industry. Raw materials used in the invention comprise 415-420g of m-chloroaniline, 710-730g of 40% sodium hydroxide and 45-55g of a catalyst. The method comprises the following steps: adding m-chloroaniline and a 40% sodium hydroxide solution and the catalyst into an autoclave; and introducing nitrogen to displace air in the autoclave, heating to 220DEG C, reacting under a pressure of 0.5MPa, collecting the obtained condensate liquid, pressurizing to 2MPa, continuously carrying out heat insulation for 12h, cooling, filtering to obtain an amino phenol sodium solution, adding 30% hydrochloric acid for a neutralization reaction until the pH value is 6, layering, rectifying, purifying to obtain an m-aminophenol finished product, packaging and warehousing. The method has the advantages of convenient and simple preparation, advanced technology, easily available materials, less equipment investment, high purity and low production cost, and the prepared m-aminophenol has the advantages of good use effect, safety and reliability.

Description

technical field [0001] The invention relates to the technical field of chemical industry, in particular to a pressurized alkaline hydrolysis method of m-chloroaniline to prepare m-aminophenol. Background technique [0002] m-Aminophenol, white crystal, reductive, easily oxidized by oxygen in the air, black in color during storage, melting point 122-123°C, soluble in hot water, ethanol and ether, soluble in cold water, insoluble in benzene And gasoline, when reacted with inorganic acid, it will form a water-soluble salt. In medicine, it can be used to make p-aminosalicylic acid, which is a good medicine for treating tuberculosis. In the dye industry, m-aminophenol can be used to make N, N-trimethyl -3-Aminophenol, used as a mordant and basic dye intermediate, as a phase-forming developer, used to manufacture 3-anilinophenol, used as an azo dye intermediate, so far, there are many processes for the synthesis of m-aminophenol , mainly include nitrobenzene method, resorcinol am...

AI Technical Summary

Problems solved by technology

[0002] m-Aminophenol, white crystal, reductive, easily oxidized by oxygen in the air, black in color during storage, melting point 122-123°C, soluble in hot water, ethanol and ether, soluble in cold water, insoluble in benzene And gasoline, when reacted with inorganic acid, it will form a water-soluble salt. In medicine, it can be used to make p-aminosalicylic acid, which is a good medicine for treating tuberculosis. In the dye industry, m-aminophenol can be used to make N, N-trimethyl -3-Aminophenol, used as a mordant and basic dye intermediate, as a phase developer, used to manufacture 3-anilinophenol, used as an azo dye intermediate, so far, there are many processes for the synthesis of m-aminophenol , mainly include nitrobenzene method, resorcinol ammonification method, m-nitrophenol electrolysis method, phenylamine hydroxylation method and m-phenylenediamine hydrochloric acid hydrolysis method, but most of them have backward technology, serious pollution, and high cost High, the recovery rate and selectivity are not high, and the equipment requirements are too high