This award supports the work of Professor Kristopher McNeill at the University of Minnesota and research of his group on metal-mediated dechlorination pathways relevant to environmental remediation. Groundwater pollution by perchloroethylene, trichloroethylene, and other chlorinated solvents is a widespread problem that threatens our water supply. Metal-mediated dechlorination processes are at the center of many of the most promising remediation methods, but very little is known about their mechanistic details. This is in large part due to the heterogeneous nature of the reactive metal sites in environmental applications. The research supported by this award is focused on filling this gap in our knowledge by studying reactions of chlorinated ethylenes with well-defined metal complexes that model the systems of environmental interest. Specifically, iron and palladium phosphine complexes that act as models for the active sites in permeable reactive barriers loaded with zero-valent iron particles and noble metal hydrogenation catalysts, respectively, will be studied. The result of these studies will be a deeper understanding of fundamental reactions that are likely involved in these real-world systems. This research advances our knowledge of carbon-chlorine activation reactions, which are central to a wide range of catalytic transformations. Additionally, the research features an international collaboration on the measurement of isotope fractionation factors of these processes will help bridge the gulf between field measurements of dechlorination reactions and how they relate to their underlying chemical mechanisms.
This project advances the commitment of NSF to sustainability through its focus on technologies for providing clean drinking water. The project features a dissemination plan that will transfer knowledge obtained through this research to the broader community of remediation practitioners. In addition, through the support of the student researchers involved, this project furthers the mission NSF to educate and train the next generation of scientists.
