Page 33 - Microsoft Word - Sulfo and Sulfa 1.doc

directly agglomerated to form compact laundry detergents without spray drying. This
ability is a major advantage because it allows manufacture of a finished laundry
formulation in low cost equipment – without the energy and environmental penalties of
spray drying. Chemithon has developed high active neutralization technology capable of
producing 70–80% active neutralized sulfonates or sulfates from any of the normally
used detergent feedstocks.

These high active pastes can then be dried to very low moisture levels
(≤5%) in either a wiped film evaporator or in the Chemithon Turbo Tube dryer. This
TM
equipment removes moisture from the detergent paste to produce a detergent noodle,
needle, pellet or powder which can be agglomerated into the finished detergent
formulation or shipped to the formulator for further processing.

Additional Equipment

The Chemithon Turbo Tube dryer (patent pending), shown in Figure 29, is a heated,
TM
vacuum flash device in which the volatile components of a surfactant slurry are removed
in a non-dusting manner. The process is carried out under carefully controlled conditions
of temperature and pressure to ensure that product quality of sensitive surfactants is not
compromised during the removal process. Because of the low production costs of this
new technology, the surfactant manufacturer can supply a low cost, inexpensive dried
detergent active to the formulator. Transportation costs are significantly reduced as well,
because water and other possible diluents are removed prior to shipping. The formulator
can use this source of active to customize the final formulation for his particular market
using inexpensive agglomeration equipment.

Production of sodium alpha sulfo methyl ester (SASME) is the final advance in
sulfonation technology discussed in this chapter. Because of the vast quantities of methyl
ester produced world wide (estimated to exceed 540,000 tons in 1995 [21] ), there is
widespread interest in using this raw material for detergent production. The Chemithon
Corporation has developed a new bleaching process for production of low disalt, light
colored SASME. Chemithon has applied for patents to cover this new process. The
process, shown in Figure 30, combines hydrogen peroxide, methanol and digested methyl
ester sulfonic acid. The hydrogen peroxide bleaches the methyl ester, while the methanol
is essential to prevent hydrolysis of the methyl ester to a disalt and methanol. Reducing
disalt is important, as disalt decreases solubility and detergency of SASME in hard water
and shortens shelf life of detergent formulations. Even if no methanol is added to the
process, methanol forms from degradation of the methyl ester under the acidic

Page 32 of 36 © 1997 The Chemithon Corporation