Person: Klitzke, Sondra
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Veröffentlichung DENANA - Designkriterien für nachhaltige Nanomaterialien(2018) Dippon-Deissler, Urs; Klitzke, Sondra; Kussatz, Carola; Lukas, Marcus; Schneider, Philipp; Völker, Doris; Deutschland. UmweltbundesamtVeröffentlichung The variable fate of Ag and TiO2 nanoparticles in natural soil solutions - sorption of organic matter and nanoparticle stability(2019) Degenkolb, Laura; Kaupenjohann, Martin; Klitzke, SondraEngineered nanoparticles (NP) like Ag and TiO2 offer unique properties for various applications. Thus, the entry of the NP in soil environments is expected to increase in the future due to their growing industrial use. To avoid potential hazards due to these anthropogenic products, NP behavior in the environment should be well understood. In natural soil solutions, we investigated NOM adsorption onto Ag and TiO2 NP and its influence on NP colloidal stability. Therefore, we extracted soil solutions from a floodplain soil (Fluvisol) and a farmland soil (Cambisol) differing in NOM quality and inorganic ion concentration. We measured the amount of adsorbed organic carbon as well as changes in aromaticity and molecular weight of NOM upon adsorption onto NP. Additionally, the size and zeta potential of NP in both soil solutions were investigated. We observed that the highly hydrophilic NOM of floodplain soil solution rich in inorganic ions strongly adsorbed to Ag but not to TiO2 NP. Instead, sorption to TiO2 NP was observed for the more hydrophobic NOM of the farmland soil with low ionic strength which did not sorb to Ag NP. These differences had a strong effect on NP stability, leading to Ag NP destabilization in case of floodplain soil solution and TiO2 NP stabilization in the presence of farmland soil solution. Our results point out the necessity of studies in more complex systems and suppose that oxic and metallic NP might show very different fate depending on the environment they are exposed to. © Springer Nature Switzerland AG 2019Veröffentlichung Einsatz von Nanomaterialien und nanoskaligen Produkten zur Abwasserbehandlung(2015) Apel, Petra; Dubbert, Wolfgang; Schwirn, Kathrin; Klitzke, Sondra; Völker, Doris; Liesegang, Christian; Winde, ChristineDie Behandlung von belastetem Wasser vor dem Einleiten in Oberflächengewässer ist eine der global vordringlichsten Herausforderungen der Zukunft. Bestehende Verfahren zur Wasser- und Abwasseraufbereitung können durch geeignete nanotechnische Anwendungen optimiert werden, die zu einer gezielteren Entfernung von Kontaminationen, besseren Energieeffizienz und geringeren Kosten führen können. Experten prognostizieren, dass der Wassersektor neben dem Energiesektor mittel- bis langfristig mit am stärksten von innovativen Anwendungen der Nanotechnik profitieren könnte. Neben dem Nutzen der Verwendung von Nanomaterialien zur Wasserbehandlung ist auch zu berücksichtigen, dass Nanomaterialien unbeabsichtigte Wirkungen auf die Umwelt und die menschliche Gesundheit hervorrufen können. Bei der Verwendung der Nanomaterialien muss beachtet werden, dass die neuartigen Eigenschaften der Nanomaterialien gegebenenfalls auch schädliche Wirkungen auf die Umwelt und den Menschen haben können.Veröffentlichung Retention and remobilization mechanisms of environmentally aged silver nanoparticles in an artificial riverbank filtration system(2018) Metreveli, George; Degenkolb, Laura; Philippe, Allan; Klitzke, Sondra; Brandt, Anja; Zehlike, LisaVeröffentlichung Transport and retention of differently coated CeO2 nanoparticles in saturated sediment columns under laboratory and near-natural conditions(2019) Degenkolb, Laura; Dippon-Deissler, Urs; Klitzke, Sondra; Pabst, SilkeWhere surface-functionalized engineered nanoparticles (NP) occur in drinking water catchments, understanding their transport within and between environmental compartments such as surface water and groundwater is crucial for risk assessment of drinking water resources. The transport of NP is mainly controlled by (i) their surface properties, (ii) water chemistry, and (iii) surface properties of the stationary phase. Therefore, functionalization of NP surfaces by organic coatings may change their fate in the environment. In laboratory columns, we compared the mobility of CeO2 NP coated by the synthetic polymer polyacrylic acid (PAA) with CeO2 NP coated by natural organic matter (NOM) and humic acid (HA), respectively. The effect of ionic strength on transport in sand columns was investigated using deionized (DI) water and natural surface water with 2.2 mM Ca2+ (soft) and 4.5 mM Ca2+ (hard), respectively. Furthermore, the relevance of these findings was validated in a near-natural bank filtration experiment using HA-CeO2 NP. PAA-CeO2 NP were mobile under all tested water conditions, showing a breakthrough of 60% irrespective of the Ca2+ concentration. In contrast, NOM-CeO2 NP showed a lower mobility with a breakthrough of 27% in DI and < 10% in soft surface water. In hard surface water, NOM-CeO2 NP were completely retained in the first 2 cm of the column. The transport of HA-CeO2 NP in laboratory columns in soft surface water was lower compared to NOM-CeO2 NP with a strong accumulation of CeO2 NP in the first few centimeters of the column. Natural coatings were generally less stabilizing and more susceptible to increasing Ca2+ concentrations than the synthetic coating. The outdoor column experiment confirmed the low mobility of HA-CeO2 NP under more complex environmental conditions. From our experiments, we conclude that the synthetic polymer is more efficient in facilitating NP transport than natural coatings and hence, CeO2 NP mobility may vary significantly depending on the surface coating. © The Author(s) 2019Veröffentlichung Aggregation of TiO2 and Ag nanoparticles in soil solution - Effects of primary nanoparticle size and dissolved organic matter characteristics(2019) Degenkolb, Laura; Peters, André; Ellerbrock, Ruth H.; Klitzke, Sondra; Zehlike, LisaThe colloidal stability of nanoparticles NP in soil solution is important to assess their potential effects on ecosystems. The aim of this work was to elucidate the interactions between initial particle size di, particle number concentration (N0) as well as the characteristics of dissolved organic matter (DOM) for stabilizing Ag NP and TiO2 NP. In batch experiments using time-resolved dynamic light scattering (DLS), we investigated the aggregation of TiO2 NP (79 nm, 164 nm) and citrate-stabilised Ag NP (73 nm, 180 nm) in Ca2+ solution (2 mM) and two soil solutions, one extracted from a farmland and one from a floodplain soil (each containing 2 mM Ca2+). Our results demonstrate that the initial particle size and the particle number concentration affected aggregation more strongly in the presence of DOM than without DOM. The composition of DOM also affected aggregate size: NP formed larger aggregates in the presence of hydrophilic DOM than in the presence of hydrophobic DOM. Hydrophilic DOM showed a larger charge density than hydrophobic DOM. If Ca2+ is present, it may bridge DOM molecules, which may lead to greater NP destabilization. The results demonstrate that DOM interaction with NP may not only vary for different DOM characteristics (i.e. charge density) but may also be influenced by the presence of multivalent cations and different NP material; thus the effect of DOM on NP colloidal stability is not uniform. © 2019 The Authors. Published by Elsevier B.V.Veröffentlichung Aggregation kinetics of TiO2 and Ag nanoparticles in soil solution(2017) Klitzke, Sondra; Zehlike, LisaVeröffentlichung The Fate of synthetic Ag Nanoparticles in Soils(2017) Klitzke, Sondra; Lang, FriederikeVeröffentlichung The fate of nanoparticles in the subsurface(2017) Klitzke, SondraVeröffentlichung Transport of perfluoroalkyl acids in a water-saturated sediment(2014) Klitzke, Sondra; Möller, Axel; Vierke, LenaThe objective of this work was to provide updated information on the development of the potentialimpact of heavy metal containing batteries on municipal waste and battery recycling processes followingtransposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 146 differenttypes of commercially available dry and button cells as well as lithium-ion accumulators for mobilephones were analysed for their mercury (Hg)-, cadmium (Cd)- and lead (Pb)-contents. The methods usedfor preparing the cells and analysing the heavy metals Hg, Cd, and Pb were either developed during a formerstudy or newly developed. Several batteries contained higher mass fractions of mercury or cadmiumthan the EU limits. Only half of the batteries with mercury and/or lead fractions above the markingthresholds were labelled. Alkaline-manganese mono-cells and Li-ion accumulators, on average, containedthe lowest heavy metal concentrations, while zinc-carbon batteries, on average, contained thehighest levels.
Quelle: ©2013 Elsevier Ltd. All rights reserved