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Publikation Qualitative assessment of the exotoxicological effects of residues generated in scandium production technologies(08.10.2020) Vaszita, Emese; Hengevoss, Dirk; Lenz, Markus; Feigl, VictoriaScandium production from wastes, such as bauxite residue or TiO2 production wastes are gaining focus due to the high economical value of this element. To evaluate the environmental impact of such production technologies a scoring and classification system was developed and adapted to the residues generated during the entire technological process chain. The system enabled us to rank the input and output materials and the residues in each technological step based on environmental toxicity and potential environmental effects.06 - PräsentationPublikation Organic photovoltaics: Potential fate and effects in the environment(Elsevier, 2012) Zimmermann, Yannick-Serge; Schäffer, Andreas; Hugi, Christoph; Fent, Karl; Corvini, Philippe; Lenz, MarkusIn times of dwindling fossil fuels it is particularly crucial to develop novel “green” technologies in order to cover the increasing worldwide demand for energy. Organic photovoltaic solar cells (OPVs) are promising as a renewable energy source due to low energy requirement for production, low resource extraction, and no emission of greenhouse gasses during use. In contrast to silicium-based solar cells, OPVs offer the advantages of light-weight, semi-transparency and mechanical flexibility. As to a possible forthcoming large-scale production, the environmental impact of such OPVs should be assessed and compared to currently best available technologies. For the first time, this review compiles the existing knowledge and identifies gaps regarding the environmental impact of such OPVs in a systematic manner. In this regard, we discuss the components of a typical OPV layer by layer. We discuss the probability of enhanced release of OPV-borne components into the environment during use-phase (e.g. UV- and biodegradation) and end-of-life phase (e.g. incineration and waste disposal). For this purpose, we compiled available data on bioavailability, bioaccumulation, biodegradation, and ecotoxicity. Whereas considerable research has already been carried out concerning the ecotoxicity of certain OPV components (e.g. nanoparticles and fullerenes), others have not been investigated at all so far. In conclusion, there is a general lack of information about fate, behavior as well as potential ecotoxicity of most of the main OPV components and their degradation/transformation products. So far, there is no evidence for a worrying threat coming from OPVs, but since at present, no policy and procedures regarding recycling of OPVs are in action, in particular improper disposal upon end-of-life might result in an adverse effect of OPVs in the environment when applied in large-scale.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Circularity and environmental sustainability of organic and printed electronics(Jenny Stanford Publishing, 2024) Le Blévennec, Kévin; Hengevoss, Dirk; Zimmermann, Yannick-Serge; Brun, Nadja; Hugi, Christoph; Lenz, Markus; Corvini, Philippe; Fent, Karl; Nisato, Giovanni; Lupo, Donald; Rudolf, SimoneIn this chapter, the possible role and impact of organic and printed electronics (OPE) in a transition toward a circular economy and more sustainable society will be discussed. The learning targets are twofold: first, understanding main environmental issues associated with the emerging field of OPE, and second, identifying, through a systemic perspective, the enabling potential of these technologies.04A - Beitrag SammelbandPublikation Life cycle assessment of a novel production route for scandium recovery from bauxite residues(Elsevier, 2024) Hengevoss, Dirk; Misev, Victor; Feigl, Viktória; Fekete-Kertész, Ildikó; Molnár, Mónika; Balomenos, Efthymios; Davris, Panagiotis; Hugi, Christoph; Lenz, MarkusScandium (Sc) has various technological applications, but the concentrations of Sc in ores are low. Both, the mining of low concentrated Sc and the production of industrial-grade Sc are a heavy burden on the environment. Bauxite residue (BR) from alumina production represents one of the major sources of Sc in Europe (Ochsenkühn-Petropulu et al., 1994). The goal of this study is to assess the environmental impacts from cradle to gate of a novel production route developed in the Scandium Aluminium Europe project (SCALE) to extract Sc at concentrations <100 ppm from BR, to concentrate and upgrade it to pure ScF3 and Sc2O3 and ultimately to refine it to an aluminium scandium master alloy with 2 % Sc mass fraction (AlSc2 %). Results show that the global warming potential (GWP), measured in CO2-eq per kg Sc2O3, generated with the novel route is about half the GWP of the state-of-the-art Sc2O3 production from rare earth tailings when applying equal allocation principles. The initial process step to dissolve BR and extract Sc consumes elevated amounts of acid and energy and is responsible for at least 80 % of the route’s total environmental impact. The amount of the generated filter cake (FC) is equal to the amount of the BR input and is a potential resource for cement clinker production. The ecotoxicological study indicates that both FC and BR are slightly ecotoxic.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Organic solvent free PbI2 recycling from perovskite solar cells using hot water(Elsevier, 05.04.2023) Schmidt, Felix; Amrein, Meret; Hedwig, Sebastian; Kober-Czerny, Manuel; Paracchino, Adriana; Holappa, Ville; Suhonen, Riikka; Schäffer, Andreas; Constable, Edwin C.; Snaith, Henry J.; Lenz, MarkusPerovskite solar cells represent an emerging and highly promising renewable energy technology. However, the most efficient perovskite solar cells critically depend on the use of lead. This represents a possible environmental concern potentially limiting the technologies’ commercialization. Here, we demonstrate a facile recycling process for PbI2, the most common lead-based precursor in perovskite absorber material. The process uses only hot water to effectively extract lead from synthetic precursor mixes, plastic- and glass-based perovskites (92.6 – 100% efficiency after two extractions). When the hot extractant is cooled, crystalline PbI2 in high purity (> 95.9%) precipitated with a high yield: from glass-based perovskites, the first cycle of extraction / precipitation was sufficient to recover 94.4 ± 5.6% of Pb, whereas a second cycle yielded another 10.0 ± 5.2% Pb, making the recovery quantitative. The solid extraction residue remaining is consequently deprived of metals and may thus be disposed as non-hazardous waste. Therefore, exploiting the highly temperature-dependent solubility of PbI2 in water provides a straightforward, easy to implement way to efficiently extract lead from PSC at the end-of-life and deposit the extraction residues in a cost-effective manner, mitigating the potential risk of lead leaching at the perovskites’ end-of-life.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Environmental selenium volatilization is possibly conferred by promiscuous reactions of the sulfur metabolism(Elsevier, 2023) Liu, Ying; Schäffer, Andreas; Martinez, Mathieu; Lenz, MarkusSelenium deficiency affects many million people worldwide and volatilization of biogenically methylated selenium species to the atmosphere may limit Se entering the food chain. However, there is very little systematic data on volatilization at nanomolar concentrations prevalent in pristine natural environments. Pseudomonas tolaasii cultures efficiently methylated Se at these concentrations. Nearly perfect linear correlations between the spiked Se concentrations and Dimethylselenide, Dimethyldiselenide, Dimethylselenylsulfide and 2-hydroxy-3-(methylselanyl)propanoic acid were observed up to 80 nM. The efficiency of methylation increased linearly with increasing initial Se concentration, arguing that the enzymes involved are not constitutive, but methylation proceeds promiscuously via pathways of S methylation. From the ratio of all methylated Se and S species, one can conclude that between 0.30% and 3.48% of atoms were Se promiscuously methylated at such low concentrations. At concentrations higher than 640 nM (∼50 μg/L) a steep increase in methylation and volatilization was observed, which suggested the induction of specific enzymes. Promiscuous methylation at low environmental concentrations calls into question that view that methylated Se in the atmosphere is a result of a purposeful Se metabolism serving detoxification. Rather, the concentrations of methylated Se in the atmosphere may be “coincidental” i.e., determined by the activity of S cycling microorganisms. Further, a steep increase in methylation efficiency when surpassing a certain threshold concentration (here ∼50 μg/L) calls into question that natural methylation can be estimated from high Se spikes in laboratory systems, yet highlights the possibility of using bacterial methylation as an effective remediation strategy for media higher concentrated in Se. © 2023 The Authors01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Ecotoxicity attenuation by acid-resistant nanofiltration in scandium recovery from TiO2 production waste(Elsevier, 2023) Fekete-Kertész, Ildikó; Stirling, Tamás; Vaszita, Emese; Berkl, Zsófia; Farkas, Éva; Hedwig, Sebastian; Remmen, Kirsten; Lenz, Markus; Molnár, Mónika; Feigl, Viktória01A - Beitrag in wissenschaftlicher ZeitschriftPublikation From trace to pure. Pilot-scale scandium recovery from TiO2 acid waste(American Chemical Society, 06.04.2023) Hedwig, Sebastian; Yagmurlu, Bengi; Peters, Edward Michael; Misev, Victor; Hengevoss, Dirk; Dittrich, Carsten; Forsberg, Kerstin; Constable, Edwin C.; Lenz, Markus01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Nanofiltration-enhanced solvent extraction of scandium from TiO acid waste(American Chemical Society, 27.04.2022) Yagmurlu, Bengi; Huang, Danyu; von Arx, Oliver; Dittrich, Carsten; Constable, Edwin; Friedrich, Bernd; Hedwig, Sebastian; Lenz, MarkusScandium is a critical raw material with a technological potential to reduce transportation costs and CO2 emissions. However, global supply and market adoption are crucially impaired by the lack of high-grade Sc ores and recovery strategies. A tandem nanofiltration solvent extraction route is demonstrated to enable effective Sc recovery from real-world acid waste from the chloride TiO2 production route. The process involving several filtration stages, solvent extraction, and precipitation was optimized, ultimately producing >97% pure (NH4)3ScF6.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Magnesium sensing via LFA-1 regulates CD8+ T cell effector function(Cell Press, 2022) Lötscher, Jonas; Martí i Líndez, Adrià-Arnau; Kirchhammer, Nicole; Cribioli, Elisabetta; Giordano Attianese, Greta Maria Paola; Trefny, Marcel P.; Rothschild, Sacha I.; Strati, Paolo; Künzli, Marco; Lotter, Claudia; Schenk, Susanne H.; Dehio, Philippe; Löliger, Jordan; Litzler, Ludivine; Schreiner, David; Koch, Victoria; Page, Nicolas; Lee, Dahye; Grählert, Jasmin; Kuzmin, Dmitry; Burgener, Anne-Valérie; Merkler, Doron; Pless, Miklos; Balmer, Maria L.; Reith, Walter; Huwyler, Jörg; Irving, Melita; King, Carolyn G.; Zippelius, Alfred; Hess, Christoph; Lenz, MarkusThe relevance of extracellular magnesium in cellular immunity remains largely unknown. Here, we show that the co-stimulatory cell-surface molecule LFA-1 requires magnesium to adopt its active conformation on CD8+ T cells, thereby augmenting calcium flux, signal transduction, metabolic reprogramming, immune synapse formation, and, as a consequence, specific cytotoxicity. Accordingly, magnesium-sufficiency sensed via LFA-1 translated to the superior performance of pathogen- and tumor-specific T cells, enhanced effectiveness of bi-specific T cell engaging antibodies, and improved CAR T cell function. Clinically, low serum magnesium levels were associated with more rapid disease progression and shorter overall survival in CAR T cell and immune checkpoint antibody-treated patients. LFA-1 thus directly incorporates information on the composition of the microenvironment as a determinant of outside-in signaling activity. These findings conceptually link co-stimulation and nutrient sensing and point to the magnesium-LFA-1 axis as a therapeutically amenable biologic system.01A - Beitrag in wissenschaftlicher Zeitschrift