Preparation method of p-aminophenetole

Abstract

The invention relates to a preparation method of p-aminophenetole, which comprises the following steps: catalytic hydrogenation reaction: in a self-absorption stirred tank reactor, under the reaction conditions of adding ethanol and introducing hydrogen, adding raw materials for mixing reaction; standing and neutralization reaction: after standing, injecting liquid ammonia into the reacted mixed solution, rotating the solution in one direction, monitoring the pH value in real time, and stopping injecting the liquid ammonia when the pH value is 7 + 0.2; carrying out solid-liquid separation: carrying out low-speed stirring type filtration by adopting a high-density filter screen, fully contacting liquid with the screen under the action of rotating flow and the action of vertical gravity and transverse rotating force at the same time, and extracting a solid catalyst of which the particle size is 0.01-0.03 mm or greater than 0.05 mm in the step; liquid-liquid separation: extracting the ethanol; and introducing the mixture into a batch-type rectifying tower, and separating p-aminophenetole and aniline. The method comprehensively improves the extraction and separation of the catalyst and ethanol, and can reduce the production cost and improve the purity of p-phenetidine.

Description

Technical field

[0001] The present invention relates to a method for preparing p-aminophenethyl ether. Background

[0002] P-Aminophenethyl ether and aniline are important organic intermediates. At present, it is mainly used for the preparation of phenacetin and ethyl vat dyes. In addition, it is also used to prepare azo dyes, ice dyes, etc. P-Aminophenethyl ether and aniline are widely used and have greater demand at home and abroad, so the synthesis of p-aminophenethyl ether and aniline has received more and more attention.

[0003] The traditional synthetic routes of p-aminophenethyl ether and aniline mainly include:

[0004] (1) Using p-nitrophenol as raw material, ethoxylation reaction with bromoethane under phase transfer catalysis is carried out to generate p-nitrophenethyl ether, and p-amino phenyl ether is generated after reduction reaction;

[0005] (2) P-nitrochlorobenzene is used as raw material, and ethanol and sodium hydroxide are used to generate p-nitrophenethyl e...

Examples

Embodiment 1

[0029] A kind of preparation method of p-aminophenyl ether, the main equipment used is: self-priming stirred kettle reactor (with shock function), enamel neutralization kettle, high-density barrel filter (with rotation function), solvent recovery device (with a certain negative pressure capacity), ammonium sulfate concentration and refining device, intermittent rectification tower.

[0030] The main steps are:

[0031]S1, catalytic hydrogenation reaction: in the self-priming stirred kettle reactor, the reaction conditions of adding ethanol and entering hydrogen, adding raw materials for mixing reaction, where the raw materials include a mixture of nitrobenzene and sulfuric acid; , the ratio of raw material nitrobenzene, sulfuric acid, ethanol mixture is 1:0.5:20 molar ratio, with Pt-C as the catalyst, the diameter of the catalyst particles is 0.01mm-10.0mm, the catalyst dosage is one thousandth of the amount of nitrobenzene, replace the air, pass into hydrogen, control the tempera...

Embodiment 2

[0043] A kind of preparation method of p-aminophenyl ether, the main equipment used is: self-priming stirred kettle reactor (with shock function), enamel neutralization kettle, high-density barrel filter (with rotation function), solvent recovery device (with a certain negative pressure capacity), ammonium sulfate concentration and refining device, intermittent rectification tower.

[0044] The main steps are:

[0045] S1, catalytic hydrogenation reaction: in the self-priming stirred kettle reactor, the reaction conditions of adding ethanol and entering hydrogen, adding raw materials for mixing reaction, where the raw materials include a mixture of nitrobenzene and sulfuric acid; The ratio of raw material nitrobenzene, sulfuric acid, ethanol mixture is 1:0.5:20 molar number ratio, with Pt-C as the catalyst, the diameter of the catalyst particles is 0.01mm-5mm, the catalyst dosage is one thousandth of the amount of nitrobenzene, replace the air, pass into hydrogen, control the temp...

Technical field

[0001] The present invention relates to a method for preparing p-aminophenethyl ether. Background

[0002] P-Aminophenethyl ether and aniline are important organic intermediates. At present, it is mainly used for the preparation of phenacetin and ethyl vat dyes. In addition, it is also used to prepare azo dyes, ice dyes, etc. P-Aminophenethyl ether and aniline are widely used and have greater demand at home and abroad, so the synthesis of p-aminophenethyl ether and aniline has received more and more attention.

[0003] The traditional synthetic routes of p-aminophenethyl ether and aniline mainly include:

[0004] (1) Using p-nitrophenol as raw material, ethoxylation reaction with bromoethane under phase transfer catalysis is carried out to generate p-nitrophenethyl ether, and p-amino phenyl ether is generated after reduction reaction;

[0005] (2) P-nitrochlorobenzene is used as raw material, and ethanol and sodium hydroxide are used to generate p-nitrophenethyl e...

Examples

Embodiment 1

[0029] A kind of preparation method of p-aminophenyl ether, the main equipment used is: self-priming stirred kettle reactor (with shock function), enamel neutralization kettle, high-density barrel filter (with rotation function), solvent recovery device (with a certain negative pressure capacity), ammonium sulfate concentration and refining device, intermittent rectification tower.

[0030] The main steps are:

[0031]S1, catalytic hydrogenation reaction: in the self-priming stirred kettle reactor, the reaction conditions of adding ethanol and entering hydrogen, adding raw materials for mixing reaction, where the raw materials include a mixture of nitrobenzene and sulfuric acid; , the ratio of raw material nitrobenzene, sulfuric acid, ethanol mixture is 1:0.5:20 molar ratio, with Pt-C as the catalyst, the diameter of the catalyst particles is 0.01mm-10.0mm, the catalyst dosage is one thousandth of the amount of nitrobenzene, replace the air, pass into hydrogen, control the tempera...

Embodiment 2

[0043] A kind of preparation method of p-aminophenyl ether, the main equipment used is: self-priming stirred kettle reactor (with shock function), enamel neutralization kettle, high-density barrel filter (with rotation function), solvent recovery device (with a certain negative pressure capacity), ammonium sulfate concentration and refining device, intermittent rectification tower.

[0044] The main steps are:

[0045] S1, catalytic hydrogenation reaction: in the self-priming stirred kettle reactor, the reaction conditions of adding ethanol and entering hydrogen, adding raw materials for mixing reaction, where the raw materials include a mixture of nitrobenzene and sulfuric acid; The ratio of raw material nitrobenzene, sulfuric acid, ethanol mixture is 1:0.5:20 molar number ratio, with Pt-C as the catalyst, the diameter of the catalyst particles is 0.01mm-5mm, the catalyst dosage is one thousandth of the amount of nitrobenzene, replace the air, pass into hydrogen, control the temp...

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