PhD candidate in the Department of Chemistry
'Chemical characterization and sediment sorption properties of surfactants found in the dispersants used to mitigate the effects of the Deep Water Horizon oil spill in the Gulf of Mexico'
Synopsis: Chemical dispersants were extensively used in the Deep Water Horizon oil spill in the Gulf of Mexico in 2010. In this talk, I will present my research using high resolution, liquid chromatography – time of flight mass spectroscopic (LC-ToF-MS) to characterize the identity and persistence of the complex mixture of surfactants and other component in Corexit® dispersants used in this spill. Our methods revealed a more complex and hydrophobic mixture of fatty acid esters than previously recognized. I will also discuss my data evaluating how these chemicals sorb to sediments collected from the Gulf of Mexico, data is important to understanding their fate and transport in this system.
Dioctyl sodium sulfosuccinate (DOSS), a major ingredient in Corexit 9527 and 9500 dispersants used to mitigate some effects of the Deep-water Horizon oil spill is known to be relatively persistent in seawater and was detected in water column and sediment samples after the spill. Because of its hydrophobic character, a better understanding of DOSS sorption is important for predicting its fate in nearshore environments. Experiments with 12 coastal sediments with varying combinations of properties (e.g., organic carbon contents of 0.18 – 8.59 %) resulted in nearly linear concentration dependence of DOSS partitioning between sediment and water at environmentally relevant concentrations (1-200 µg/L). Total organic carbon content was found to be a good predictor of sorption, with carbon normalized sorption coefficients averaging 7500 ± 2500 L/Kg. These data will give a better basis for predicting the sorption of DOSS at environmentally relevant concentrations.
Biography: Benedette was born in Lagos State, Nigeria. She found her passion for science in high school. After emigrating to the US, she attended CUNY, College of Staten Island and City College of New York, where she majored in chemistry. As an undergraduate student, her participation in the Louis Stokes Alliances for Minority Participation (LSAMP) program and subsequently the Bridges to Doctorate (BD) program as a graduate student in City College, strongly influenced her decision to enroll in the doctoral program in chemistry at Stony Brook University. Benedette is an AGEP-T FRAME and Turner Fellow in the Center for Inclusive Education.
Monday, May 9, 2016 at 12:00 PM