HR: 0800h
AN: H51G-0854    [Abstracts]
TI: Mobility of Multi-walled Carbon Nanotubes in Porous Media
AU: * O'Carroll, D M
EM: docarroll@eng.uwo.ca
AF: Department of Civil & Environmental Engineering, The University of Western Ontario, 1151 Richmond St., London, On N6A 5B9, Canada
AU: Liu, X
EM: xliu233@uwo.ca
AF: Department of Civil & Environmental Engineering, The University of Western Ontario, 1151 Richmond St., London, On N6A 5B9, Canada
AU: Petersen, E
EM: epeterse@umich.edu
AF: Department of Civil and Environmental Engineering, University of Michigan, 1351 Beal Avenue, Ann Arbor, MI 48109-2125, United States
AU: Huang, Q
EM: qhuang@uga.edu
AF: Department of Crop and Soil Sciences, University of Georgia, 1109 Experiment Street, Griffin, GA 30223, United States
AU: Anderson, L
EM: cla28@cornell.edu
AF: Biological and Environmental Engineering, Cornell University, 328 Riley-Robb Hall, Ithaca, NY 14853-5701, United States
AB: Engineered multi-walled carbon nanotubes (MWCNTs) are the subject of intense research and are expected to gain widespread usage in a broad variety of commercial products. However concerns have been raised regarding their potential environmental and health risks. The mobility of MWCNTs in porous media is examined in this study through one dimensional flow-through column experiments under conditions representative of subsurface and drinking water treatment systems. The goal of this work was to determine dominant MWCNT removal mechanisms and factors that control MWCNT transport. Results demonstrate that pore water velocity strongly influenced MWCNT transport, a result that stands in contrast to traditional colloid filtration theory, which suggests a relatively minor effect of flow velocity in comparison to Brownian diffusion. Experiments conducted at different ionic strengths indicate that both particle deposition and straining are important MWCNT removal mechanisms from the aqueous phase. Given these findings, traditional colloid filtration theory may not be appropriate for the prediction of MWCNT mobility in porous media. This may be due to the large aspect ratio of the MWCNTs and the importance of straining in MWCNT removal.
DE: 1800 HYDROLOGY
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1806 Chemistry of fresh water
DE: 1831 Groundwater quality
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: 2007 Fall Meeting