Sodium 3-nitrobenzenesulphonate

Uses:
Sodium 3-nitrobenzenesulphonate is used as a resist agent for vat dyes and sulfur dyes, a color protectant for dyes, a rust remover for ships, and a nickel stripping agent for electroplating. It is also an intermediate for dyes and vanillin.

Packaging: 25kg/bag

Production Method:

In an enamel-lined reactor, first add 350 parts of fuming sulfuric acid, controlling the reactor temperature at 0-5℃. Slowly add nitrobenzene while stirring. After adding 132 parts of nitrobenzene within 1 hour, raise the reactor temperature to 100℃ and maintain this temperature for 2 hours. Take a sample to determine the sulfonation endpoint (drop 1-2 drops of the material into a 10ml test tube containing clear water; no turbidity indicates the endpoint has been reached). After the sulfonation reaction is complete, cool the reactor and slowly add ice water. Add 2000 parts of salt after approximately 3 hours. After salting out for several hours, let stand overnight, filter, and press dry to obtain the intermediate m-nitrobenzenesulfonic acid. Dissolve the m-nitrobenzenesulfonic acid in 500 parts of hot water by boiling. Remove a small amount of sulfone. Neutralize with 50 parts of soda ash, then decolorize with activated carbon. Filter while hot, and cool the filtrate to crystallize. Wash the filter cake with a small amount of water and dry below 50℃ to obtain the finished product.