Page 27 - Microsoft Word - Sulfo and Sulfa 1.doc

Figure 24. Chemithon Annular Falling Film Reactor

SO 3 GAS

SO 3 GAS
COOLING
WATER OUT

ORGANIC ORGANIC
FEED FEED
COOLING
WATER IN
RECYCLE RECYCLE
IN
IN
COOLING COOLING
WATER WATER
PRODUCT AND
EXHAUST GAS

Stepan Company patented a multi-tube reactor in 1965. They currently operate a large
[7]
number of these reactors worldwide. Similar reactor designs are manufactured by other
firms [19, 20] .

A continuous neutralizer system is illustrated in Figure 27. The neutralizer combines
sulfonic acid or organo-sulfuric acid with a neutralizing agent, additives, and diluent
(water), in a dominant bath neutralization. The result is a solution of neutral active
matter (slurry or paste) of the desired composition and pH. Caustic soda, usually 50 wt%
NaOH, is the most common neutralizing agent. However, caustic potash, aqueous
ammonia, triethanolamine, and other agents are compatible with the neutralizer. A
recycle loop circulates neutral slurry through a heat exchanger to remove heat of
neutralization, mixing and pumping. Individual metering and/or gear pumps feed
sulfonic acid, neutralizing agent, dilution water, buffer solution and any additives into the
loop to mix through a high shear mixer. A positive displacement pump circulates paste

Page 26 of 36 © 1997 The Chemithon Corporation