Details zur Publikation

Referenztyp Zeitschriften
DOI / URL Link
Titel (primär) Isotope fractionation of diethyl phthalate during oxidation degradation by persulfate activated with zero-valent iron
Autor Min, N.; Yao, J.; Wu, L.; Amde, M.; Richnow, H.H.; Chen, Y.; Wu, C.; Li, H.
Journal / Serie Chemical Engineering Journal
Erscheinungsjahr 2022
Department ISOBIO
Band/Volume 435
Heft Part 1
Seite von art. 132132
Sprache englisch
Topic T7 Bioeconomy
Keywords Compound-specific stable isotope analysis; Diethyl phthalate; Persulfate; Carbon and hydrogen isotopic fractionation; Zero-valent iron
Abstract This study reports the 13C and 2H isotope fractionation associated with the oxidation of diethyl phthalate (DEP) by persulfate (PS) activated with zero-valent iron (ZVI) using three concentration levels (0.2, 0.5 and 1.0 g L-1) at different pH values, 3, 7 and 11, respectively. The results showed that the degradation of DEP followed a pseudo first-order kinetics. The fastest degradation was found at neutral conditions (pH 7). Similar carbon and hydrogen isotope fractionation (εC and εH) was observed during the oxidation of DEP by ZVI activated PS at pH 3, 7 and 11. At ZVI concentration of 0.5 g L-1, the correlation of 13C and 2H fractionation (Λ) were obtained to be 12.7 ± 3.5, 11.1 ± 4.2 and 12.0 ± 2.9 at pH 3, 7 and 11, respectively. The concentration of ZVI has no effect on the correlation of 13C and 2H fractionation (Λ). In addition, radical quenching approach and electron paramagnetic resonance (EPR) were combined to explore the dominant radical species in the ZVI activated PS reaction, and hydroxyl radical (•OH) was found to be the predominant radical at all pH studied. The results of CSIA show the addition of •OH to the aromatic ring of DEP is the main reaction mechanism, which is consistent with the results of radical quenching experiment and EPR study. Carbon and hydrogen apparent kinetic isotope effects (AKIEs) obtained from •OH reactions with DEP supported the hypothesis of C-H bond cleavage. Thus, carbon and hydrogen isotope enrichment factors clearly distinguish the different reaction mechanisms and hence, are a promising approach to improve understanding of radical species reaction pathways for chemical oxidation of DEP.
dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=25135
Min, N., Yao, J., Wu, L., Amde, M., Richnow, H.H., Chen, Y., Wu, C., Li, H. (2022):
Isotope fractionation of diethyl phthalate during oxidation degradation by persulfate activated with zero-valent iron
Chem. Eng. J. 435 (Part 1), art. 132132