title: Effects of oil dispersants on settling of marine sediment particles and particle-facilitated distribution and transport of oil components.
abstract: This work investigated effects of three model oil dispersants (Corexit EC9527A, Corexit EC9500A and SPC1000) on settling of fine sediment particles and particle-facilitated distribution and transport of oil components in sediment-seawater systems. All three dispersants enhanced settling of sediment particles. The nonionic surfactants (Tween 80 and Tween 85) play key roles in promoting particle aggregation. Yet, the effects varied with environmental factors (pH, salinity, DOM, and temperature). Strongest dispersant effect was observed at neutral or alkaline pH and in salinity range of 0-3.5wt%. The presence of water accommodated oil and dispersed oil accelerated settling of the particles. Total petroleum hydrocarbons in the sediment phase were increased from 6.9% to 90.1% in the presence of Corexit EC9527A, and from 11.4% to 86.7% for PAHs. The information is useful for understanding roles of oil dispersants in formation of oil-sediment aggregates and in sediment-facilitated transport of oil and PAHs in marine eco-systems.
authors.affiliation: Environmental Engineering Program, 238 Harbert Engineering Center, Auburn University, Auburn, AL 36849, USA.
authors.forename: Zhengqing
authors.initials: Z
authors.lastname: Cai
authors.affiliation: Environmental Engineering Program, 238 Harbert Engineering Center, Auburn University, Auburn, AL 36849, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Fu
authors.affiliation: Environmental Engineering Program, 238 Harbert Engineering Center, Auburn University, Auburn, AL 36849, USA.
authors.forename: Wen
authors.initials: W
authors.lastname: Liu
authors.affiliation: Environmental Engineering Program, 238 Harbert Engineering Center, Auburn University, Auburn, AL 36849, USA; Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China.
authors.forename: Kunming
authors.initials: K
authors.lastname: Fu
authors.affiliation: Bureau of Ocean Energy Management, GOM Region, Office of Environment, New Orleans, LA 70123, USA.
authors.forename: S E
authors.initials: SE
authors.lastname: O'Reilly
authors.affiliation: Environmental Engineering Program, 238 Harbert Engineering Center, Auburn University, Auburn, AL 36849, USA. Electronic address: zhaodon@auburn.edu.
authors.forename: Dongye
authors.initials: D
authors.lastname: Zhao
mesh_terms: D019015:Geologic Sediments / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008962:Models, Theoretical; D010578:Petroleum / Q000032:analysis*; D059392:Petroleum Pollution / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D054712:Salinity; D012623:Seawater / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry*; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical
keywords: Crude oil; Dispersant; Oil transport; PAH; Sediment; Sedimentation