The Development of In-situ NMR Photoreactors and Analysis of Photochemical Processes in the Environment

Photolysis is a major abiotic process in the environment. Current understanding of environmental photolytic processes is limited due to restricted information offered by conventional analytical techniques and lack of in-situ studies. In-situ nuclear magnetic resonance (NMR) photoreactors were developed to directly integrate light sources with NMR spectroscopy to probe into environmental photochemistry in a non-invasive manner. They were applied to a series of environmental systems including an atmospheric pollutant, crude oil extracts, groundwater (at natural abundance), and dissolve organic matter (DOM). Intermediates and degradation products were identified along with kinetic profiles of specific compounds in complex environmental mixtures. It was also shown to be a great non-invasive chromatographic tool to investigate the phototransformation of DOM. Also, two dimensional (2D) NMR experiments were used to characterize and quantify components in DOM. Overall, the work demonstrates that in-situ NMR spectroscopy is an important analytical tool in unraveling complex environmental photolytic processes.M.Sc.2017-03-15 00:00:0