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Ergebnisse nach Hochschule und Institut
Publikation KVI-Konformität in der Nachhaltigkeitsberichterstattung der IWB. Analyse und Ergänzungen(Hochschule für Life Sciences FHNW, 2024) Heuberger, Noomi; Hengevoss, Dirk; Industrielle Werke Basel (IWB)11 - Studentische ArbeitPublikation Machbarkeitsstudie zur Wiederverwertung von Kupfer und Plastik aus Kabelresten(Hochschule für Life Sciences FHNW, 2024) Dahinden, Jonas; Lenz, Markus; Recycling Huber11 - Studentische ArbeitPublikation Silber und Indium Recycling aus Perowskit-Photovoltaikzellen mittels «Layer-by-Layer» Membranen(Hochschule für Life Sciences FHNW, 2024) Müller, Tobias; Lenz, Markus11 - Studentische ArbeitPublikation Citizen science-based waste diaries. An exploratory case study of household waste in Switzerland(MDPI, 30.04.2024) Breitenmoser, Lena; Behner, David; Baertsch, Alessia; Mondardini, Maria Rosa; Hugi, ChristophSustainable Development Goal 12 (SDG 12) and national waste reduction goals require frequent waste analyses for monitoring and governance decisions. We developed and tested a citizen science (CS)-based household waste diary for ten consecutive days with 89 volunteer households in Switzerland as a complementary monitoring option to official composition analyses. Discrepancies between the CS-based household diary data and the official composition analyses ranged between 55–65% less reported waste quantities for minerals, compound products, and plastics and 80–90% less for paper, avoidable food waste, and glass. Household waste diaries should be digitalized and prolonged to 21–28 days, and volunteers from different demographic groups are needed to produce stratified, representative results. We conclude that a hybrid CS study design involving waste composition analyses and waste diaries could reduce self-reporting biases while increasing the monitoring frequencies of household waste compositions. CS-based hybrid household waste projects can be a powerful means to complement the measures identified in the 2022 Swiss action plan against food waste and for data reporting for the SDG 12.3 Food Waste Index.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Implementation of co-processing of waste in cement kilns for Ukraine(Igor Sikorsky Kyiv Polytechnic Institute, 2021) Kleshchov, Anton Yosypovych; Hengevoss, Dirk; Hugi, Christoph; Mutz, Dieter; Terentiev, Oleh Markovych; Shevchuk, Nataliia Anatoliivna05 - Forschungs- oder ArbeitsberichtPublikation 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 Scattered and transmitted light as surrogates for activated carbon residual in advanced wastewater treatment processes. Investigating the influence of particle size(Elsevier, 04/2024) Kirchen, Franziska; Fundneider, Thomas; Gimmel, Louis; Thomann, Michael; Pulfer, Michael; Lackner, SusanneThe use of powdered activated carbon (PAC) is a common process in advanced wastewater treatment to remove micropollutants. Retention and separation of PAC is essential as PAC loaded with micropollutants should not be released into the environment. Determining the activated carbon (AC) residual in the effluent poses a challenge, as there is currently no on-line measurement method. In this study, the correlation between turbidity, measured by scattered light, and absorption at wavelength of 550 nm (Absorption550 nm), measured by transmitted light, was investigated in relation to the AC residue. Linear correlations for turbidity (R2 = 0.95) and Absorption550 nm (R2 = 1.00) to AC concentrations were observed in both laboratory and full-scale experiments in a pilot plant where superfine PAC was added prior to Pile Cloth Media Filtration (PCMF). Decreasing the particle size (d50) while maintaining the same AC concentration leads to increased turbidity: Therefore, a fourfold reduction in d50 results in a 2- to 3-fold increase in turbidity, whereas a 30-fold reduction in d50 leads to a 6-to 8-fold increase. Furthermore, the original wastewater turbidity led to a parallel shift in the linear correlation between turbidity and AC. Coagulant doses of up to 400 mg Me3+/g AC resulted in a 50% reduction in turbidity. However, higher concentrations from 400 to 1,000 mg Me3+/g AC resulted in increased turbidity with only a 30% reduction compared to the initial turbidity. The study also highlights the significance of AC particle size in optical measurements, impacting result accuracy.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 Zeitschrift