2-(ethylamino)toluene-4-sulphonic acid synthesis

Yield:98-40-8 1004 kg

Reaction Conditions:

with sulfuric acid at 50 - 65; for 6 h;Large scale;Temperature;

Steps:

1.2; 2.2; 3.2; 4.2; 1.2; 2.2; 3.2; 4.2; 5.2 Step 2. Sulfonation reaction: N-ethyl o-toluidine and fuming sulfuric acid undergo sulfonation reaction to produce 3-ethylamino p-toluenesulfonic acid;

The specific operation steps of the sulfonation reaction are as follows:According to the molar mass ratio of N-ethyl o-toluidine to fuming sulfuric acid 1:1.96,First add 1876Kg of fuming sulfuric acid into the sulfonation kettle,Then, slowly drop 727Kg of N-ethyl o-toluidine at a dropping rate of 22-28kg/h,During the dripping process, strictly control the temperature in the sulfonation kettle to be less than or equal to 50 degrees Celsius.After the dripping is over, the materials are pressed into the insulation kettle with nitrogen,Incubate at 65 degrees Celsius for 6 hours,Then press the material into the dilution kettle with nitrogen,Water and ice cubes are pre-installed in the dilution kettle,It can reduce the pressed material to below 20,The sulfonation reaction product 3-ethylamino p-toluenesulfonic acid crystallized out,Centrifugal separation, filtrate A and filter cake A,The filtrate A is a 30% dilute sulfuric acid solution,Discharge into the storage tank to be processed, the filter cake A is 3-ethylamino-p-toluenesulfonic acid and sent to the alkali melting kettle;This step obtains 1004Kg of 3-ethylamino p-toluenesulfonic acid;

References:

CN112574043,2021,A Location in patent:Paragraph 0060; 0063-0064