Adapted from Shreves, Chemical process Industries
Main reaction
Alkylbenzene + Oleum -----> Alkylbenzene sulphonate + sulfuric acid
Process steps
Sulfonation-sulfation
The alkylbenzene is introduced continuously into sullfonator with the requisite amount of oleum. The temperature should be maintained about 55C. Fatty tallow alcohol and more oleum are fed into sulfonated mixture.The mixture is then pumped to the sulfater (should also operate arroun50-55C)
Neutralization
The sulfonated –sulfated product is neutralized with NaOH solution under controlled temperature to maintain fluidity of the surfactant slurry. The surfactant slurry is conducted to storage.
The surfactant slurry, sodium tripolyphostphate and most of the miscellaneous additives are introduced into the crutcher. A considerable amount of the water is removed and the paste is thickened by sodium tripolyphostphate hydration reaction.
The mixture is pumped to an upper story where it is sprayed under high pressure into the 24m high spray tower, counter to hot air from the furnace. Dried granules of acceptable shape and size and suitable density are formed. The dried granules are transferred to a upper story by an air life which cools them from 115C and stabilize the granules. They are then separated in a cyclone , screened, perfumed and packed.
Detergent production process video
Detergent production process video