abstract
The aqueous solubility of hexafluorobenzene has been determined, at 298.15 K, using a shake-flask method with a spectrophotometric quantification technique. Furthermore, the solubility of hexafluorobenzene in saline aqueous solutions, at distinct salt concentrations, has been measured. Both salting-in and salting-out effects were observed and found to be dependent on the nature of the cationic/anionic composition of the salt. COSMO-RS, the Conductor-like Screening Model for Real Solvents, has been used to predict the corresponding aqueous solubilities at conditions similar to those used experimentally. The prediction results showed that the COSMO-RS approach is suitable for the prediction of salting-in/-out effects. The salting-in/-out phenomena have been rationalized with the support of COSMO-RS sigma-profiles. The prediction potential of COSMO-RS regarding aqueous solubilities and octanol-water partition coefficients has been compared with typically used QSPR-based methods. Up to now, the absence of accurate solubility data for hexafluorobenzene hampered the calculation of the respective partition coefficients. Combining available accurate vapor pressure data with the experimentally determined water solubility, a novel air-water partition coefficient has been derived. (C) 2011 Elsevier Ltd. All rights reserved.
keywords
ORGANIC-COMPOUNDS; SCREENING MODEL; REAL SOLVENTS; WATER; CHLOROBENZENES; HYDROCARBONS; TEMPERATURE; COEFFICIENT; CHEMICALS; SALINITY
subject category
Environmental Sciences & Ecology
authors
Schroder, B; Freire, MG; Varanda, FR; Marrucho, IM; Santos, LMNBF; Coutinho, JAP
our authors
Bernd Schroder
Post-doc Fellowship
Isabel Maria Delgado Jana Marrucho Ferreira
Full professor
Mara Guadalupe Freire Martins
Coordinating ResearcherGroups
G4 - Renewable Materials and Circular Economy
G5 - Biomimetic, Biological and Living Materials
acknowledgements
Mara G. Freire and Bernd Schroder acknowledge Fundacao para a Ciencia e a Tecnologia (FCT) and the European Social Fund (ESF) under the 3rd Community Support Framework (CSF) for the award of post-doctoral grants (Grant Numbers SFRH/BPD/41781/2007 and SFRH/BPD/38637/2007).