title: Effects of pure and dyed PCE on physical and interfacial properties of remedial solutions.
abstract: Hydrophobic dyes have been used to visually distinguish dense non-aqueous phase liquid (DNAPL) contaminants from background aqueous phases and soils. The objective of this study was to evaluate the effects of a dyed DNAPL, 0.5 g Oil-Red-O/l of PCE, on the physical properties of remedial solutions: water, co-solvents (50, 70, and 90% (v/v) ethanol), and surfactants (4% (w) sodium dihexyl sulfosuccinate). This study compared the densities, viscosities, and interfacial tensions (IFTs) of the remedial solutions in contact with both dyed and undyed PCE. The presence of the dye in PCE substantially alters the IFTs of water and ethanol solutions, while there is no apparent difference in IFTs of surfactant solutions. The remedial solutions saturated with PCE showed higher viscosities and densities than pure remedial solutions. Solutions with high ethanol content exhibited the largest increases in liquid density. Because physical properties affect the flow of the remedial solutions in porous media, experiments using dyed DNAPLs should assess the influence of dyes on fluid and interfacial properties prior to remediation process analysis.
authors.affiliation: Office of Research and Development, US Environmental Protection Agency, 919 Kerr Research Drive, P O Box 1198, Ada, OK 74820, USA. jeong.seung-woo@epa.gov
authors.forename: Seung-Woo
authors.initials: SW
authors.lastname: Jeong
authors.forename: A Lynn
authors.initials: AL
authors.lastname: Wood
authors.forename: Tony R
authors.initials: TR
authors.lastname: Lee
mesh_terms: D001391:Azo Compounds; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004396:Coloring Agents; D004784:Environmental Monitoring; D012995:Solubility; D012997:Solvents; D013500:Surface Tension; D013501:Surface-Active Agents; D013750:Tetrachloroethylene / Q000032:analysis*; D014241:Trichloroethylene / Q000032:analysis*; D014783:Viscosity; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D012997:Solvents; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical; D014241:Trichloroethylene; C011049:oil red O; D013750:Tetrachloroethylene