Multi-element compound-specific stable isotope analysis (2H, 13C, 15N, 33/34S) to characterize the mechanism of sulfate and hydroxyl radical reaction and photolysis of benzothiazole

作者：Haiyan Yu, Limin Ma, Steffen Kümmel, Xiao Liu, Thomas Schaefer, Hartmut Herrmann, Hans H. Richnow · 发表于：Water Research · 年份：2025 · DOI：10.1016/j.watres.2025.123479 · 被引用次数：8 · 研究领域：Atmospheric chemistry and aerosols、Advanced oxidation water treatment、Analytical chemistry methods development

• Assessment of ME isotope enrichment factors of benzothiazole for photolysis, SO 4 •− and • OH reactions. • Benzothiazole reacts with SO 4 •− leading to the cleavage of the C−S bond and subsequent opening of the heterocyclic ring • • OH reactions with benzothiazole is initiated by the cleavage of the C−H bond at the benzene ring • ME isotope fractionation of benzothiazole suggest different mechanisms upon photolysis by >190 nm and >280 nm irradiation • First study to explored the diagnostic potential of ME isotope fractionation to track mechanisms Benzothiazole was taken as a simple emerging aromatic heterocyclic contaminant as model compounds for analyzing multi-element isotope (ME-CSIA) fractionation ( 2 H, 13 C, 15 N and 33/34 S) for the first time, in order to obtain information on the reaction mechanism upon sulfate and hydroxyl radical reactions and photolysis. The sulfur isotope effects 33 / 34 S to allow to explore reactions mechanisms with respect to mass dependent and independent kinetic isotope effect. For compound specific isotope analysis for 2 H, 13 C, and 15 N using GC-pyrolysis and combustion IRMS techniques were applied and for 33/34 S isotope analysis a novel approach using GC- multi collector ICPMS were developed. The multi-element fractionation factors of the radical reactions were obtained to characterize the first irreversible degradation step in order explore their potential to analyze radical oxidation processes in technical and natural systems. The h...