1.It is obtained by reacting p-toluenesulfonyl chloride with ammonia water. Process flow: firstly put an appropriate amount of ice water into the amination pot, and then put the p-toluenesulfonyl chloride and ammonia water metered according to the mass ratio (p-toluenesulfonyl chloride: pure ammonia = 1:0.2) into the pot. Start the stirrer, use the cold liquid of the aminating pot jacket to control the temperature in the pot to about 70 °C (the reaction is a lot of exothermic), and then cool down to about 30 °C. The amine is filtered in a filter drum and washed with warm water, and dried to obtain a solid powdery crude p-toluenesulfonamide.
The crude p-toluenesulfonamide contains a small amount of an oily colored substance of the orthologous by-product. The use of the p-amino acid in the sodium hydroxide solution and the decolorization with activated carbon can achieve the purpose of purification and purification. The material quality ratio is crude para-amine: 30% sodium hydroxide liquid base: water = 100:45:1300; crude para-amine: activated carbon = 100: (2.5-3.5). According to the formula amount, the water and caustic soda are put into the purifying pot, the jacketed steam valve is opened and heated to 70 ° C, and then the formula amount of the crude para-amine is added, and the stirrer is started, and when the crude para-amine is dissolved, the fraction is divided. Add the formula amount of activated carbon, continue to stir for 0.5h, put the liquid into the filter bucket, filter it hot, wash it with hot water, and blot it dry.
The filtrate is then pumped into the refining pot, neutralized with hydrochloric acid to pH = 2-3, and the temperature is lowered to about 30-35 ° C. The liquid is filtered in a filter tank, washed with water until neutral, and transferred to a centrifuge to dry. For the finished product with 10% water content, if it needs dry product, it is sent to the airflow dryer for drying to obtain 1% p-toluenesulfonamide finished product.
2. P-toluenesulfonyl chloride and pure ammonia were sequentially added to ice water to control the mass ratio of p-toluenesulfonyl chloride to pure ammonia to be 1:0.2, and the reaction was carried out with stirring, and the temperature was controlled to 70 ° C under cooling. After the reaction is completed, it is cooled, filtered, and washed to obtain a crude product. The crude product is washed with alkali, decolorized, washed with water, neutralized, filtered, washed with water, and dried to obtain a finished product.