Details zur Publikation

Referenztyp Zeitschriften
DOI / URL Link
Titel (primär) Isotope fractionation in phase-transfer processes under thermodynamic and kinetic control – Implications for diffusive fractionation in aqueous solution
Autor Kopinke, F.-D.; Georgi, A.; Roland, U.;
Journal / Serie Science of the Total Environment
Erscheinungsjahr 2018
Department TUCHEM;
Band/Volume 610–611
Sprache englisch;
POF III (gesamt) T41;
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 Querschnittsthemen 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.
ID 19392
dauerhafte UFZ-Verlinkung 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