Uranium and neptunium retention mechanisms in Gallionella ferruginea/ferrihydrite systems for remediation purposes
| Autor: | Frank Bok, André Rossberg, Lotta Hallbeck, Evelyn Krawczyk-Bärsch, Katja Schmeide, Andreas C. Scheinost, Katharina Müller, Jana Lehrich |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
X-ray absorption spectroscopy
Microorganism Environmental remediation Bacteriogenic iron oxyhydroxides XAS Health Toxicology and Mutagenesis Neptunium chemistry.chemical_element Sorption General Medicine Actinide 010501 environmental sciences Uranium 01 natural sciences Pollution Impacts in Environmental Trends Health and Well Being: A Global pollution Problem Partition coefficient Actinides Ferrihydrite ATR FT-IR spectroscopy chemistry Environmental chemistry Environmental Chemistry 0105 earth and related environmental sciences |
| Zdroj: | Environmental Science and Pollution Research International 'Environmental Science and Pollution Research ', vol: 28, pages: 18342-18353 (2021) |
| ISSN: | 1614-7499 0944-1344 |
| Popis: | The ubiquitous β-Proteobacterium Gallionella ferruginea is known as stalk-forming, microaerophilic iron(II) oxidizer, which rapidly produces iron oxyhydroxide precipitates. Uranium and neptunium sorption on the resulting intermixes of G. ferruginea cells, stalks, extracellular exudates, and precipitated iron oxyhydroxides (BIOS) was compared to sorption to abiotically formed iron oxides and oxyhydroxides. The results show a high sorption capacity of BIOS towards radionuclides at circumneutral pH values with an apparent bulk distribution coefficient (Kd) of 1.23 × 104 L kg−1 for uranium and 3.07 × 105 L kg−1 for neptunium. The spectroscopic approach by X-ray absorption spectroscopy (XAS) and ATR FT-IR spectroscopy, which was applied on BIOS samples, showed the formation of inner-sphere complexes. The structural data obtained at the uranium LIII-edge and the neptunium LIII-edge indicate the formation of bidentate edge-sharing surface complexes, which are known as the main sorption species on abiotic ferrihydrite. Since the rate of iron precipitation in G. ferruginea-dominated systems is 60 times faster than in abiotic systems, more ferrihydrite will be available for immobilization processes of heavy metals and radionuclides in contaminated environments and even in the far-field of high-level nuclear waste repositories. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink