title: Co-transport of chlordecone and sulfadiazine in the presence of functionalized multi-walled carbon nanotubes in soils.
abstract: Batch and saturated soil column experiments were conducted to investigate sorption and mobility of two14C-labeled contaminants, the hydrophobic chlordecone (CLD) and the sulfadiazine (SDZ), in the absence or presence of functionalized multi-walled carbon nanotubes (MWCNTs). The transport behaviors of CLD, SDZ, and MWCNTs were studied at environmentally relevant concentrations (0.1-10 mg L-1) and they were applied in the column studies at different times. The breakthrough curves and retention profiles were simulated using a numerical model that accounted for the advective-dispersive transport of all compounds, attachment/detachment of MWCNTs, equilibrium and kinetic sorption of contaminants, and co-transport of contaminants with MWCNTs. The experimental results indicated that the presence of mobile MWCNTs facilitated remobilization of previously deposited CLD and its co-transport into deeper soil layers, while retained MWCNTs enhanced SDZ deposition in the topsoil layers due to the increased adsorption capacity of the soil. The modeling results then demonstrated that the mobility of engineered nanoparticles (ENPs) in the environment and the high affinity and entrapment of contaminants to ENPs were the main reasons for ENP-facilitated contaminant transport. On the other hand, immobile MWCNTs had a less significant impact on the contaminant transport, even though they were still able to enhance the adsorption capacity of the soil.
authors.affiliation: Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany; Institute for Environmental Research (Biology V), RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany. Electronic address: m.zhang@fz-juelich.de.
authors.forename: Miaoyue
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany; TU Freiberg, Department of Hydrogeology, 09596 Freiberg, Germany.
authors.forename: Irina
authors.initials: I
authors.lastname: Engelhardt
authors.affiliation: Department of Environmental Sciences, University of California Riverside, Riverside, CA 92521, USA.
authors.forename: Jirka
authors.initials: J
authors.lastname: Šimůnek
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, U. S. Salinity Laboratory, Riverside, CA 92507, USA.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Bradford
authors.affiliation: Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Kasel
authors.affiliation: Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
authors.forename: Anne E
authors.initials: AE
authors.lastname: Berns
authors.affiliation: Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
authors.forename: Harry
authors.initials: H
authors.lastname: Vereecken
authors.affiliation: Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
authors.forename: Erwin
authors.initials: E
authors.lastname: Klumpp
mesh_terms: D000327:Adsorption; D007631:Chlordecone / Q000032:analysis*; D008956:Models, Chemical; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry; D013411:Sulfadiazine / Q000032:analysis* / Q000737:chemistry; D027981:Symporters
chemical_list: D037742:Nanotubes, Carbon; D012987:Soil; D012989:Soil Pollutants; D027981:Symporters; D013411:Sulfadiazine; D007631:Chlordecone
keywords: Colloid-facilitated contaminant transport; Multi-walled carbon nanotubes; Numerical modeling; Retention profile; Soil