Details

Autor(en) / Beteiligte

• Poulson, Simon R
• Drever, James I

Titel

Stable Isotope (C, Cl, and H) Fractionation during Vaporization of Trichloroethylene

Ist Teil von

• Environmental science & technology, 1999-10, Vol.33 (20), p.3689-3694

Ort / Verlag

Washington, DC: American Chemical Society

Erscheinungsjahr

1999

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Stable isotope fractionation during vaporization of trichloroethylene has been measured, with possible application as a technique to investigate subsurface behavior. The equilibrium value of Δ13Cvapor - liquid has been measured between 5 and 35 °C, and Δ13Cvapor - liquid, Δ37Clvapor - liquid, and ΔD vapor - liquid have been measured during progressive evaporation of liquid trichloroethylene at 22 ± 2 °C. Equilibrium values of Δ13Cvapor - liquid show a total range of 0.07−0.82‰, with a trend of decreasing Δ13Cvapor - liquid with increasing temperature, from approximately +0.7‰ at 5−15 °C to approximately +0.1‰ at 35 °C. Progressive evaporation experiments yield values of Δ13Cvapor - liquid = +0.35‰ and +0.24‰, Δ37Clvapor - liquid = −1.64‰, and ΔD vapor - liquid = +8.9‰. The positive values for carbon and hydrogen isotope fractionation, while unexpected, are consistent with available quantitative and qualititative data for trichloroethylene and other contaminant hydrocarbons, but a satisfactory explanation for these observations, particularly in combination with the negative value for chlorine, remains elusive. Vapor−liquid fractionation factors have application to the investigation of the behavior of trichloroethylene at contaminated sites, particularly sites undergoing remediation by techniques such as soil vapor extraction and soil bioventing.