Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.chemosphere.2016.02.122
Title (Primary) Solubility enhancement of dioxins and PCBs by surfactant monomers and micelles quantified with polymer depletion techniques
Author Schacht, V.J.; Grant, S.C.; Escher, B.I.; Hawker, D.W.; Gaus, C.
Source Titel Chemosphere
Year 2016
Department ZELLTOX
Volume 152
Page From 99
Page To 106
Language englisch
Keywords Partition constants; Surfactant monomers and micelles; Silanization; poly(dimethylsiloxane); Polychlorinated biphenyls; Polychlorinated dibenzo-p-dioxins
UFZ wide themes RU3;
Abstract Partitioning of super-hydrophobic organic contaminants (SHOCs) to dissolved or colloidal materials such as surfactants can alter their behaviour by enhancing apparent aqueous solubility. Relevant partition constants are, however, challenging to quantify with reasonable accuracy. Partition constants to colloidal surfactants can be measured by introducing a polymer (PDMS) as third phase with known PDMS-water partition constant in combination with the mass balance approach. We quantified partition constants of PCBs and PCDDs (log KOW 5.8–8.3) between water and sodium dodecyl sulphate monomers (KMO) and micelles (KMI). A refined, recently introduced swelling-based polymer loading technique allowed highly precise (4.5–10% RSD) and fast (<24 h) loading of SHOCs into PDMS, and due to the miniaturisation of batch systems equilibrium was reached in <5 days for KMI and <3 weeks for KMO. SHOC losses to experimental surfaces were substantial (8–26%) in monomer solutions, but had a low impact on KMO (0.10–0.16 log units). Log KMO for PCDDs (4.0–5.2) were approximately 2.6 log units lower than respective log KMI, which ranged from 5.2 to 7.0 for PCDDs and 6.6–7.5 for PCBs. The linear relationship between log KMI and log KOW was consistent with more polar and moderately hydrophobic compounds. Apparent solubility increased with increasing hydrophobicity and was highest in micelle solutions. However, this solubility enhancement was also considerable in monomer solutions, up to 200 times for OCDD. Given the pervasive presence of surfactant monomers in typical field scenarios, these data suggest that low surfactant concentrations may be effective long-term facilitators for subsurface transport of SHOCs.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=17226
Schacht, V.J., Grant, S.C., Escher, B.I., Hawker, D.W., Gaus, C. (2016):
Solubility enhancement of dioxins and PCBs by surfactant monomers and micelles quantified with polymer depletion techniques
Chemosphere 152 , 99 - 106 10.1016/j.chemosphere.2016.02.122