Carbon and Chlorine Isotope Fractionation Patterns Associated with Different Engineered Chloroform Transformation Reactions

• DOI: 10.1021/acs.est.7b00679
• Publication Date: 2017-05-09T07:12:05Z
• Authors: Clara Torrentó; Jordi Palau; Diana Rodríguez-F...; Benjamin Heckel; Armin Meyer; Cristina Domènech; Mònica Rosell; Albert Soler; Martin Elsner; Daniel Hunkeler
• Keywords: Persulfate; Reductive Dechlorination; Kinetic isotope effect; Isotopes of chlorine

To use compound-specific isotope analysis for confidently assessing organic contaminant attenuation in the environment, fractionation patterns associated with different transformation mechanisms must first be explored laboratory experiments. deliver this information common groundwater chloroform (CF), study investigated time both carbon and chlorine three engineered reactions: oxidative C–H bond cleavage using heat-activated persulfate, under alkaline conditions (pH ∼ 12) reductive C–Cl by cast zerovalent iron, Fe(0). Carbon values were −8 ± 1‰ −0.44 0.06‰ oxidation, −57 5‰ −4.4 0.4‰ hydrolysis 11.84 0.03), −33 11‰ −3 dechlorination, respectively. apparent kinetic effects (AKIEs) general agreement expected (C–H oxidation Fe(0)-mediated dechlorination E1CB elimination mechanism during hydrolysis) where a secondary AKIECl (1.00045 0.00004) was observed oxidation. The dual carbon-chlorine (Δδ13C vs Δδ37Cl) thermally activated persulfate (17 2 13.0 0.8, respectively) Fe(0) (8 2) establish base to identify quantify these CF degradation field.