SIZE-SELECTIVE EXTRACTION OF POLYCYCLIC AROMATIC-HYDROCARBONS FROM A MICROEMULSION SYSTEM USING CYCLODEXTRINS

A procedure for the size-selective extraction of polycyclic aromatic hydrocarbons (PAHs) from an oil-in-water microemulsion system is reported. This extraction is achieved through a precipitation/extraction process involving cyclodextrins (CDs) and select PAHs in the microemulsion. Results are confirmed by fluorescence analysis of supernatant and precipitate. The size relationship between the PAH and CD cavity appears to be a major factor in the selectivity of the process. For example, after extraction with β-CD, the fluorescence intensity of naphthalene in the microemulsion is reduced to 3.7% of its original value, whereas with α- or γ-CD the intensity remains unchanged. In studies of a model system, the microemulsion involves a three-component mixture of PAHs; α-, β-, and γ-CD are investigated for their extraction capabilities for these three PAHs. © 1993 Academic Press, Inc.