title: Development of an in Situ NMR Photoreactor To Study Environmental Photochemistry.
abstract: Photochemistry is a key environmental process directly linked to the fate, source, and toxicity of pollutants in the environment. This study explores two approaches for integrating light sources with nuclear magnetic resonance (NMR) spectroscopy: sample irradiation using a "sunlight simulator" outside the magnet versus direct irradiation of the sample inside the magnet. To assess their applicability, the in situ NMR photoreactors were applied to a series of environmental systems: an atmospheric pollutant (p-nitrophenol), crude oil extracts, and groundwater. The study successfully illustrates that environmentally relevant aqueous photochemical processes can be monitored in situ and in real time using NMR spectroscopy. A range of intermediates and degradation products were identified and matched to the literature. Preliminary measurements of half-lives were also obtained from kinetic curves. The sunlight simulator was shown to be the most suitable model to explore environmental photolytic processes in situ. Other light sources with more intense UV output hold potential for evaluating UV as a remediation alternative in areas such as wastewater treatment plants or oil spills. Finally, the ability to analyze the photolytic fate of trace chemicals at natural abundance in groundwater, using a cryogenic probe, demonstrates the viability of NMR spectroscopy as a powerful and complementary technique for environmental applications in general.
authors.affiliation: Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6, Canada.
authors.forename: Liora
authors.initials: L
authors.lastname: Bliumkin
authors.forename: Rudraksha
authors.initials: R
authors.lastname: Dutta Majumdar
authors.forename: Ronald
authors.initials: R
authors.lastname: Soong
authors.forename: Antonio
authors.initials: A
authors.lastname: Adamo
authors.affiliation: Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6, Canada.
authors.forename: Jonathan P D
authors.initials: JP
authors.lastname: Abbatt
authors.affiliation: Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6, Canada.
authors.forename: Ran
authors.initials: R
authors.lastname: Zhao
authors.affiliation: Ontario Ministry of the Environment , Toronto, Ontario M9P 3 V6, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: Reiner
authors.affiliation: Department of Chemistry, University of Toronto , Toronto, Ontario M5S 3H6, Canada.
authors.forename: André J
authors.initials: AJ
authors.lastname: Simpson
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D010777:Photochemistry; D010782:Photolysis; D013472:Sunlight; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D014874:Water Pollutants, Chemical