Health & Environmental Research Online (HERO)


Print Feedback Export to File
2147942 
Technical Report 
Surfactant-Enhanced In situ Biodegradation of Strongly Sorbing Organic Substances in Soil Environments 
Jaffe, PR 
1994 
NTIS/03005383_a 
GRA and I 
GRA and I 
Low-solubility Polycyclic Aromatic Hydrocarbons such as phenanthrene areeasily biodegradable but due to sorption onto soil or/or their presence in a non-aqueous phase, their bioavailability is greatly reduced. In an aqueous environment where surfactants exist above their critical micelleconcentration hydrophobic contaminant will partitioning into the hydrophobic core of the micelle. This enhances the apparent solubility of these hydrocarbons and therefore also their desorption from soils. Conceivably, in the absence of any inhibitory effects, such surfactants may enhance the biodegradation of the hydrocarbon. Through a set of screening experiments a group of non-ionic surfactants were identified which do not inhibit the bacterial degradation of the phenanthrene. A mathematical model was formulated to describe the interaction of the biomass-contaminant- water-surfactant system. The model assumes that the surfactant affects the solubility of phenanthrene and does not affect the biochemical characteristics of the biomass. An effective bioavailable concentration was defined. The model predicts experimental data well indicating that a part of the phenanthrene in the micelle phase can be degraded simultaneously with the phenanthrene in the aqueous phase. (jg) p.2.