Sa. Smith et al., PERFORMANCE AND CHEMICAL-STABILITY OF A NEW CLASS OF ETHOXYLATED SULFATE SURFACTANTS IN A SUBSURFACE REMEDIATION APPLICATION, Colloids and surfaces. A, Physicochemical and engineering aspects, 116(3), 1996, pp. 225-239
The suitability of a surfactant for use in subsurface remediation depe
nds on performance, toxicity and biodegradability. In order to increas
e the performance of a series of edible, polyethoxylated sorbitol este
rs, one or two sulfate groups were added to the hydrophilic poly(ethyl
ene oxide) moieties. The solubilization and salt tolerance of these su
rfactants were good, but they readily formed a mesophase when contacte
d with a common soil at a high concentration. Crystals, which have the
same maltese-cross patterns as liquid crystals, are also present when
the mesophase forms. CMC of these surfactants are reported as well as
soil adsorption and chlorinated organic solute solubilization data. T
hese surfactants were found to undergo degradation at moderate tempera
tures; a proposed mechanism for the breakdown and data on the rate of
degradation are presented.