| Summary: | 碩士 === 國立中央大學 === 環境工程學系 === 85 === AbstractThe solubility enhancement of nonionic organic compounds
(NOCs) by surfactants may play an important role in chemical and
biological remediation of contaminated soils and sediments. The
effects of micelle-forming surfactants on sorption of benzene,
toluene, ethylbenzene, p-xylene, lindane, a-BHC, and heptachlor
epoxide in clay and natural soil - water systems were
intestigated.The sorbed Domiphen Bromide (DB) molecules
increased the sorption capacity of soil phase, resulted in Kmn＞
Kd of organic-chlorinated pesticides. When equilibrium
concentration above the critical micelle concentration(CMC), DB
micelles in aqueous competed with the natural sorbed DB and soil
organic matter (SOM), so their partition coefficients reduce and
Kmn＞Kcmc.Nonionic surfactant Triton X-100 (TX-100) can not be
sorbed on Ca-Montmorillonite efficiently. There were more TX-100
molecules sorbed on Ca-Montmorillonite when the concentration
above CMC. As a result, the partition coefficients of organic-
chlorinated pesticides with Kcmc＞Kmn＞Kd. Because moleculae
weight of TX-100 is much lower than SOM and it contects high
polaritive hydrophilic group, after SOM sorbes TX-100, SOM
becomes worse partition medium for organic-chlorinated
pesticides.Then, the partition coefficients increased with
decreasing of TX-100 equilibrium concentrations.BTEX have higher
water solubility, which in essence reduced their partition
efficiency for TX-100. In attition, SOM behavedas better
partition phase when TX-100 incorporated into SMO resulting in
Kcmc＞Kmn＞Kd.Keywords : NOCs, Surfactant, Micelle, CMC,
Sorption, Partition, Solubility Enhancement
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