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Kern-Schale Katalysatorsysteme für geringe Edelmetallbeladungen, hohe Umwandlungseffizienzen und hohe Lebensdauern in der Wasserelektrolyse mit saurer Polymerelektrolytmembran, Teilvorhabenbeschreibung: Computergestützte Vorhersage Stabiler Kern-Schale Konfigurationen

Ziel dieses Teilprojekts ist das Screening von Kern-Schale Grenzflächen nach thermodynamisch stabilen Materialkombinationen durch atomistische Simulationen. Für die rigorose Bestimmung der entsprechenden Grenzflächenenergien müssen unterschiedliche Facetten und Terminierungen aller Materialien (oxidisches Titan, Tantal, Zinn, Niob und Iridium) berücksichtigt werden. Zudem ist die Bestimmung der genauen Grenzflächenstruktur ein komplexes globales Optimierungsproblem. Um diese Fragestellung zu lösen, sollen im Rahmen dieses Arbeitspaketes hochgenaue reaktive Kraftfelder für die Zielmaterialien entwickelt werden. Dies wird durch maschinelles Lernen (ML) auf Basis von Dichtefunktionaltheorie (DFT) Trainingsdaten erfolgen. Da diese Kraftfelder 3-4 Größenordnungen schnellere Simulationen als DFT ermöglichen kann die strukturelle Diversität der Grenzflächen (inklusive der Berücksichtigung von Defekten und Fehlstellen) auf diese Weise ausführlich erkundet werden.

Metallsalzextraktion

Die Metallsalzextraktion hat ihre industrielle Profilierung in den 40iger Jahren bei der Uranextraktion erlebt. Im weiteren erstreckte sich die Anwendung auf teure Metalle, wie Vanadium, Zirkon, Hafnium, Niob und Tantal. Erst in den 60iger Jahren gelang der Durchbruch mit der Gewinnung von Kupfer aus sehr verduennten Laugen. Heute wird diese Trennoperation grob gesagt fuer das halbe Periodensystem verwendet. Im Zuge von Umweltschutzerwaegungen werden auch immer billigere Metalle, wie z.B. Zink, Arsen, damit behandelt. Der Wert- bzw. Schadmetallgehalt im Abwasser liegt bei dieser Methode i.a. zwischen 0,5 und 20 g/l. Das Ziel dieser Unit Operation ist dabei entweder eine Reinigung eines Elektrolyten von Begleitelementen oder eine Aufkonzentrierung, die eine Weiterbearbeitung oekonomischer werden laesst, sowie die Umwandlung einer Spezies in eine einfacher gewinnbare Form. Aktuelle Probleme, die von uns zur Zeit behandelt werden, ist die Abtrennung des Schadstoffes Arsen aus einem Kupferelektrolyten, eine analoge Gewinnung eines Wertmetalls aus einem Zinkelektrolyten, eine Rueckfuehrung von Nickel, Zink etc. aus Spuelwaessern in der Galvanoindustrie, eine selektive Trennung der Edelmetalle Silber, Kupfer und Polladium sowie eine Aufarbeitung von Nickel aus einer chemischen Reize.

Ahr river overbank sediments: XRF elemental composition data set (Mayschoß-Transect, core Ahr2022-1_1, Ahr2022-1_2, Ahr2022-2_1, Ahr2022-2_2)

The elemental composition of samples from four sediment cores from the Mayschoß floodplain (Ahr river) was determined by X-ray fluorescence spectrometry (XRF). In the first step of preparation, large organic matter and pebbles were removed from freeze-dried samples (8 g) by sieving (2 mm). Subsequently, the samples were powdered and homogenised with vibratory Retsch mill MM 200. The uniform pills for the analysis were pressed with a carbon-based binding agent by Vaneox press at 20 t for 2 min. The elemental analysis of 50 elements was conducted in a He atmosphere using a Spectro Xepos energy dispersive XRF spectrometer. The surface elevation was extracted from Brell et al. (2023).

Whole-rock chemical analyses from the Heldburg dyke swarm

In the project "Geochemistry and geochronology of the Heldburg dyke swarm, Central European Volcanic Province" we conducted geochemical and geochronological investigations on mafic dykes and former magma chambers of the Heldburg dyke swarm. The latter is part of the Central European Volcanic Province and positioned in the South of Thuringia and the North of Bavaria (Germany). It consists of several hundred mafic NNE-SSW striking dykes with an usual thickness of < 1m and few former magma chambers. All of these have an atypical position within the Central European Volcanic Province located away from Hercynian massifs and major rift axes and were hitherto poorly investigated. In general, 10 different locations of the Heldburg dyke swarm were sampled for whole-rock analyses and 4 different locations were chosen for determining their apatite and zircon ages. The fieldwork was conducted between March 2022 and December 2023. The analytical work was done between June 2022 and April 2024 at the Department of Geodynamics and Geomaterials Research, University of Würzburg (samples preparation, X-ray fluorescence), at the GeoZentrum Nordbayern, University of Erlangen (trace element contents, LA-ICP-MS) and at FIERCE (Frankfurt Isotope & Element Research Center), Goethe University Frankfurt (apatite and zircon ages, LA-ICP-MS). Here, we present the full dataset of 55 whole-rock chemical analyses (X-ray fluorescence, LA-ICP-MS) from ten locations of the Heldburg dyke swarm.

X-ray Fluorescence (XRF) measurements of floodplain sediments from NEP 1, NEP 2 and NEP 3 from Nördlingen, southern Germany

This data set presents bulk sample-based X-ray Fluorescence (XRF) measurements. For XRF sample preparation freeze-dried sediments from silt-clay overbank deposits of the Eger floodplain in Southern Germany were seaved (2mm) to discard the gravel fraction and large organic matter. Further homogenization was undertaken by grinding the samples with PM 200 planetary ball mill from Retsch. 8 g of sediment sample (<30 µm) homogenized in the ball mill were mixed with 2 g of special wax and homogenized with a shaker. Uniform pellets were formed using a Vaneox press at 20 t for 2 minutes. Elemental analyses were conducted in a He atmosphere using a Spectro Xepos energy dispersive XRF spectrometer.

H2020-EU.3.5. - Societal Challenges - Climate action, Environment, Resource Efficiency and Raw Materials - (H2020-EU.3.5. - Gesellschaftliche Herausforderungen - Klimaschutz, Umwelt, Ressourceneffizienz und Rohstoffe), Recovery of Tungsten, Niobium and Tantalum occurring as by-products in mining and processing waste streams (TARANTULA)

Sediment core and pore water data for AL557

Sediment cores and pore water cores were taken in the Skagerrak and North Sea with a multicorer on cruise AL557 (June 2021). The sediment cores were sliced onboard into 1 cm slices and frozen directly (-20°C). Pore water samples were taken with rhizon samplers (0.15 µm pore size, CSS; Rhizosphere, Netherlands) from intact sediment cores and frozen directly (-20°C). In the laboratory, the sediments were freeze-dried, sieved (<2mm) and milled. For organic carbon (after acidification) and total carbon and nitrogen contents, the samples were analyzed using an Euro EA 3000 (Euro Vector SPA) Elemental Analyzer, delta 15N was measured with a FlashEA 1112 elemental analyzer coupled to a MAT 252 (Thermo Fisher Scientific) isotope ratio mass spectrometer (https://doi.org/10.1016/j.orggeochem.2009.05.008; lab 3). For trace metal analysis, the sediments were digested with HBF4+HNO3+HCl (https://doi.org/10.1039/D0AY01049A) and the pore water samples were acidified with HNO3 prior to 10-fold dilution with HNO3. Trace elements were measured by ICP-MS/MS (Agilent 8800, Agilent Technologies, Japan).

Metal distribution for sediment samples of the cruise AT004

Offshore wind energy is a steadily growing sector contributing to the worldwide energy production. The impact of these offshore constructions on the marine environment, however, remains unclear in many aspects. In fact, little is known about potential emissions from corrosion protection systems such as organic coatings or galvanic anodes composed of Al and Zn alloys, used to protect offshore structures. In order to assess potential chemical emissions from offshore wind farms and their impact on the marine environment water and sediment were taken in and around offshore wind farms of the German Bight between 12.04.2021 and 23.04.2021 within the context of the Hereon-BSH project OffChEm II. The surface sediment samples were taken by a box grab, homogenized, freeze-dried and wet-sieved to gain the <20 µm grain size fraction. The <20 µm grain size fraction was acid digested and measured by ICP-MS/MS for their (trace) metal mass fractions.

XRF data sheet: Weiße Elster overbank silt-clay deposition (SC40 core, Salsitz transect)

We used stationary XRF spectrometry for analysing elemental composition of Holocene floodplain sediments from a recovered core form the Weiße Elster floodplain. For XRF sample preparation freeze-dried catchment sediments (8 g) were seaved (2mm) to discard the gravel fraction and large organic matter. Further homogenization was undertaken by grinding the samples with a vibratory Retsch mill MM 200. We created uniform pellets by pressing the powdered samples with a carbon-based binding agent in a Vaneox press at 20 t for 2 min. We conducted elemental analyses in a He atmosphere using a Spectro Xepos energy dispersive XRF spectrometer. The total drilling depth of SC40 core is 275 cm. We conducted stationary XRF measurements of 52 samples.

KMU-Innovativ - Ressourceneffizienz: Entwicklung und Bewertung innovativer Recyclingwege zur Rückgewinnung von Tantal aus Elektronikabfällen

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