Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1016/j.jhazmat.2014.08.046
Titel (primär) Compound specific stable isotope analysis (CSIA) to characterize transformation mechanisms of α-hexachlorocyclohexane
Autor Zhang, N.; Bashir, S.; Qin, J.; Schindelka, J.; Fischer, A.; Nijenhuis, I.; Herrmann, H.; Wick, L.Y. ORCID logo ; Richnow, H.H.
Quelle Journal of Hazardous Materials
Erscheinungsjahr 2014
Department ISOBIO; UMB
Band/Volume 280
Seite von 750
Seite bis 757
Sprache englisch
Keywords Alpha-hexachlorocyclohexane (α-HCH); AKIE; Compound Specific Stable Isotope Analysis (CSIA); Enantiomer Specific Stable Isotope Analysis (ESIA)
UFZ Querschnittsthemen RU3;
Abstract A systematic investigation of environmentally relevant transformation processes of alpha-hexachlorocyclohexane (α-HCH) was performed in order to explore the potential of compound specific stable isotope analysis (CSIA) to characterize reaction mechanisms. The carbon isotope enrichment factors (ɛC) for the chemical transformations of α-HCH via direct photolysis, indirect photolysis (UV/H2O2), hydrolysis, electro-reduction or reduction by Fe0 were quantified and compared to those previously published for biodegradation. Hydrogen abstraction by hydroxyl radicals generated by UV/H2O2 led to ɛC of −1.9 ± 0.2‰ with an apparent kinetic carbon isotope effect (AKIEC) of 1.012 ± 0.001. Dehydrochlorination by alkaline hydrolysis yielded ɛC of −7.6 ± 0.4‰ with AKIEC of 1.048 ± 0.003. Dechlorination either by homolytic bond cleavage in direct photolysis (ɛC = −2.8 ± 0.2‰) or single-electron transfer in electro-reduction (ɛC = −3.8 ± 0.4‰) corresponded to AKIEC of 1.017 ± 0.001 and 1.023 ± 0.003 respectively. Dichloroelimination catalyzed by Fe0 via two-electron transfers resulted in ɛC of −4.9 ± 0.1‰. AKIEC values assuming either a concerted or a stepwise mechanism were 1.030 ± 0.0006 and 1.015 ± 0.0003 respectively. Contrary to biodegradation, no enantioselectivity of α-HCH was observed in chemical reactions, which might be used to discriminate chemical and biological in situ transformations.
Zhang, N., Bashir, S., Qin, J., Schindelka, J., Fischer, A., Nijenhuis, I., Herrmann, H., Wick, L.Y., Richnow, H.H. (2014):
Compound specific stable isotope analysis (CSIA) to characterize transformation mechanisms of α-hexachlorocyclohexane
J. Hazard. Mater. 280 , 750 - 757 10.1016/j.jhazmat.2014.08.046