The recent BP Deepwater Horizon oil spill has resulted in releases of unprecedented amounts of crude oil and oil dispersants into the Gulf of Mexico. Many petroleum hydrocarbons and PAHs are known to be carcinogenic, highly adsorptive to sediment and recalcitrant to natural attenuation. The overall goal of this explorative research is to fill the knowledge gap on the roles of photochemical reaction and ozonation in oil weathering and to determine the effects of the oil dispersants and adsorption on these chemical processes.
Degradation of oil paraffins of C10-C35 and PAHs (polycyclic aromatic compounds) will be tested under simulated Alabama solar irradiation and in the presence of various concentrations of Corexit 9500 and Corexit 9527. Photo-chemical degradation rates and ozonation rates will be determined through batch experiments and modeled using proper kinetic models that can facilitate assessment of transformation and fate of the oil components under natural and engineered conditions. Effects of the dispersants and sediment adsorption on the degradation rates will be explored. The results are critical for sound assessment of environmental fate of persistent oil hydrocarbons and impacts of the oil spill on the Gulf coast ecosystems.