Page 16 - Microsoft Word - Sulfo and Sulfa 1.doc

Figure 16. Continuous High Active Alkylate Sulfonation with Oleum

Neutralized
Settler Detergent
Slurry
Alkyl Benzene Reaction
From Storage Coil
Spent
Acid
Oleum Sulfonation Dilution Neutralization
From Cooler Cooler Cooler
Storage
Proportioning Mixing Water Mixing Alkali Mixing
Pump Pump Pump Pump

Sulfonic
Sulfonation Dilution Concentration Neutralization

are digested in a plug flow reactor and then dilution water (approximately 13% by
weight) is added in a second mixing loop. A second heat exchanger removes the heat of
dilution. The diluted sulfuric acid and alkylbenzene sulfonic acid are separated in a
continuous settler. The sulfonic acid is then continuously neutralized with aqueous
sodium hydroxide solution in a third, cooled mixing loop. Sulfate levels as low as 10%
in the final product can be achieved in this equipment. Total processing time is less than
one hour. The equipment can also be used to sulfate detergent range alcohols for use in
laundry powders if a high level of sulfate in the product can be tolerated. The sulfates are
present because the separation process cannot be used when sulfating alcohols. If water
is added to the alcohol sulfuric acid/sulfuric acid mixture, the alcohol sulfuric acid
immediately hydrolyzes. Additionally, mixed products containing both alkyl benzene
sulfonates and alcohol sulfates can be manufactured as shown in Figure 17. In this case
alkylate is sulfonated first, followed by sulfation of the alcohol. Some of the excess
sulfuric acid from the sulfonation stage is used to react with the alcohol and the
combined mixture is immediately neutralized. Because no separation stage is used, the
resultant product is high in sulfate.

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