title: Limited transport of functionalized multi-walled carbon nanotubes in two natural soils.
abstract: Column experiments were conducted in undisturbed and in repacked soil columns at water contents close to saturation (85-96%) to investigate the transport and retention of functionalized (14)C-labeled multi-walled carbon nanotubes (MWCNT) in two natural soils. Additionally, a field lysimeter experiment was performed to provide long-term information at a larger scale. In all experiments, no breakthrough of MWCNTs was detectable and more than 85% of the applied radioactivity was recovered in the soil profiles. The retention profiles exhibited a hyper-exponential shape with greater retention near the column or lysimeter inlet and were successfully simulated using a numerical model that accounted for depth-dependent retention. In conclusion, results indicated that the soils acted as a strong sink for MWCNTs. Little transport of MWCNTs is therefore likely to occur in the vadose zone, and this implies limited potential for groundwater contamination in the investigated soils.
authors.affiliation: Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany. d.kasel@fz-juelich.de
authors.forename: Daniela
authors.initials: D
authors.lastname: Kasel
authors.forename: Scott A
authors.initials: SA
authors.lastname: Bradford
authors.forename: Jiří
authors.initials: J
authors.lastname: Simůnek
authors.forename: Thomas
authors.initials: T
authors.lastname: Pütz
authors.forename: Harry
authors.initials: H
authors.lastname: Vereecken
authors.forename: Erwin
authors.initials: E
authors.lastname: Klumpp
mesh_terms: D060587:Groundwater / Q000737:chemistry*; D008956:Models, Chemical; D037742:Nanotubes, Carbon / Q000032:analysis / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*
chemical_list: D037742:Nanotubes, Carbon; D012987:Soil; D012989:Soil Pollutants
keywords: Carbon nanotube; Lysimeter; Retention profile; Transport modeling; Undisturbed soil