Solubilization of polycyclic aromatic hydrocarbons by perfluorinated surfactant micelles

Due to their chemical and thermal stability, perfluorinated surfactants (PF Ss) are promising materials for the development of novel environmental reme diation applications. This stability also leads to the persistence of PFS i n the environment; therefore, their properties and behavior should be well understood. This study focused on polycyclic aromatic hydrocarbon (PAH) and PFS interactions, particularly the solubilization of PAHs by PFS micelles. Naphthalene. phenanthrene, and pyrene were selected as representative PAHs and an anionic PFS. ammonium perfluorooctanoate (APFO) was used. Critical micelle concentration (CMC) values of APFO measured by surface tension, flu orescence probe, and solubility enhancement methods fell in the range of 20 -30 mM at 22 +/- 1 degreesC. Apparent solubilities of molecular oxygen and PAHs in APFO micellar solutions depended linearly on the APFO concentration . Molar solubilization ratio (MSR) values were determined to be 9.50 x 10(- 4), 4.17 x 10(-3), 2.31 x 10(-4), and 4.09 x 10(-5) and mole fraction micel lar partition coefficient (K-mic) values were found to be 1.89 x 10(2), 9.5 0 x 10(2), 2.12 x 10(3), and 3.79 x 10(3) for oxygen, naphthalene, phenanth rene, and pyrene, respectively at 22 +/- 1 degreesC. log K-mic values for t hree PAHs were shown to be linearly correlated with the log values of octan ol-water partition coefficients (log K-ow). (C) 2001 Elsevier Science Ltd. All rights reserved.