Dehalogenation Mechanisms from 37Cl/35Cl and 13C/12C Isotope Analysis
As a result of their widespread use as industrial solvents, chlorinated ethenes are among the most frequently detected groundwater contaminants. Biodegradation of these compounds under reducing conditions often leads to the accumulation of even more toxic degradation products such as cis-dichloroethene (cisDCE) and vinyl chloride (VC) from tetrachloroethene (PCE) or trichloroethene (TCE). Understanding the degradation pathways and the underlying reaction mechanisms is therefore of great relevance for contaminated site remediation and water management. While mechanistic insight has been obtained in chemical model reactions, methods are needed which prove that the same mechanism is indeed at work in natural biodegradation. We aim to bridge this gap with isotope measurements of the elements 37Cl/35Cl and 13C/12C.
- To advance the dual (C, Cl) compound specific isotope analysis as a powerful tool to differentiate microbial degradation pathways (reductive vs. oxidative) of chlorohydrocarbons
- To investigate the reaction mechanisms of chlorinated ethylenes with different chemical model systems
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