Publication Details |
| Category | Text Publication |
| Reference Category | Journals |
| DOI | 10.1016/j.scitotenv.2017.08.063 |
| Title (Primary) | Isotope fractionation in phase-transfer processes under thermodynamic and kinetic control – Implications for diffusive fractionation in aqueous solution |
| Author | Kopinke, F.-D.; Georgi, A.; Roland, U. |
| Journal | Science of the Total Environment |
| Year | 2018 |
| Department | TUCHEM |
| Volume | 610–611 |
| Page From | 495 |
| Page To | 502 |
| Language | englisch |
| Supplements | https://ars.els-cdn.com/content/image/1-s2.0-S0048969717320612-mmc1.docx |
| Keywords | Isotopic fractionation; Phase-transfer kinetics; Diffusion; Partitioning; Solvent extraction; Evaporation |
| UFZ wide themes | RU3 |
| Abstract | Diffusive isotope fractionation of organic compounds in aqueous solution was investigated by means of liquid-liquid and liquid-gas partitioning experiments under kinetic control. The two-film model was used to describe phase-transfer kinetics. It assumes the diffusion of solutes across a stagnant water boundary layer as the rate-controlling step. For all investigated solutes (benzene-D0 and -D6, toluene-D0, -D5, and -D8, cyclohexane-D0 and -D12), there was no significant observable fractionation effect between nondeuterated and perdeuterated isotopologues, resulting in a ratio of diffusion coefficients Dlight: Dheavy = 1.00 ± 0.01. In addition, isotope fractionation due to equilibrium partitioning of solutes between water and n-octane or gas phase was measured. The deuterated compounds are more hydrophilic than their light isotopologues in all cases, giving rise to fractionation coefficients αHpart = Koctane/water,H: Koctane/water,D = 1.085 to 1.15. Thus, thermodynamic fractionation effects are much larger than diffusion fractionation effects. Methodical and environmental implications of these findings are discussed. |
| Persistent UFZ Identifier | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=19392 |
| Kopinke, F.-D., Georgi, A., Roland, U. (2018): Isotope fractionation in phase-transfer processes under thermodynamic and kinetic control – Implications for diffusive fractionation in aqueous solution Sci. Total Environ. 610–611 , 495 - 502 |
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