title: Modeling aggregation and sedimentation of nanoparticles in the aquatic environment.
abstract: With nanoparticles being used more and more in consumer and industrial products it is almost inevitable that they will be released into the aquatic environment. In order to understand the possible environmental risks it is important to understand their behavior in the aquatic environment. From laboratory studies it is known that nanoparticles in the aquatic environment are subjected to a variety of processes: homoaggregation, heteroaggregation to suspended particulate matter and subsequent sedimentation, dissolution and chemical transformation. This article presents a mathematical model that describes these processes and their relative contribution to the behavior of nanoparticles in the aquatic environment. After calibrating the model with existing data, it is able to adequately describe the published experimental data with a single set of parameters, covering a wide range of initial concentrations. The model shows that at the concentrations used in the laboratory, homoaggregation and sedimentation of the aggregates are the most important processes. As for the natural environment much lower concentrations are expected, heteroaggregation will play the most important role instead. More experimental datasets are required to determine if the process parameters that were found here are generally applicable. Nonetheless it is a promising tool for modeling the transport and fate of nanoparticles in watersheds and other natural water bodies.
authors.affiliation: Deltares, P.O. Box 177, 2600 MH Delft, The Netherlands; Earth Surface Science, IBED, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands. Electronic address: arjen.markus@deltares.nl.
authors.forename: A A
authors.initials: AA
authors.lastname: Markus
authors.affiliation: Earth Surface Science, IBED, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: J R
authors.initials: JR
authors.lastname: Parsons
authors.affiliation: Deltares, P.O. Box 177, 2600 MH Delft, The Netherlands.
authors.forename: E W M
authors.initials: EW
authors.lastname: Roex
authors.affiliation: Earth Surface Science, IBED, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands; KWR Watercycle Research Institute, Nieuwegein, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: de Voogt
authors.affiliation: Deltares, P.O. Box 177, 2600 MH Delft, The Netherlands; Earth Surface Science, IBED, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: R W P M
authors.initials: RW
authors.lastname: Laane
mesh_terms: D019015:Geologic Sediments / Q000032:analysis* / Q000737:chemistry; D008956:Models, Chemical; D008962:Models, Theoretical; D053758:Nanoparticles / Q000032:analysis / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: D014874:Water Pollutants, Chemical
keywords: Aggregation; Modeling; Nanoparticles; Sedimentation