Sorption of iodine in soils: insight from selective sequential extractions and X-ray absorption spectroscopy
Autor: | Beate Riebe, Claudia M. König, Fabian Köhler, Andreas C. Scheinost, Alex Hölzer, Clemens Walther |
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Rok vydání: | 2019 |
Předmět: |
XAFS
Health Toxicology and Mutagenesis Iodide Iodates chemistry.chemical_element Context (language use) 010501 environmental sciences Iodine complex mixtures 01 natural sciences Soil chemistry.chemical_compound iodate Environmental Chemistry sequential extraction Organic matter soils Iodate 0105 earth and related environmental sciences chemistry.chemical_classification sorption iodine Soil organic matter Sorption Soil classification iodite General Medicine Iodides Pollution X-Ray Absorption Spectroscopy chemistry Environmental chemistry Adsorption Oxidation-Reduction |
Zdroj: | Environmental Science and Pollution Research 23(2019), 23850-23860 |
ISSN: | 1614-7499 0944-1344 |
Popis: | The environmental fate of iodine is of general geochemical interest as well as of substantial concern in the context of nuclear waste repositories and reprocessing plants. Soils, and in particular soil organic matter (SOM), are known to play a major role in retaining and storing iodine. Therefore, we investigated iodide and iodate sorption by four different reference soils for contact times up to 30 days. Selective sequential extractions and X-ray absorption spectroscopy (XAS) were used to characterize binding behavior to different soil components, and the oxidation state and local structure of iodine. For iodide, sorption was fast with 73 to 96% being sorbed within the first 24 h, whereas iodate sorption increased from 11-41% to 62-85% after 30 days. The organic fraction contained most of the adsorbed iodide and iodate. XAS revealed a rapid change of iodide into organically bound iodine when exposed to soil, while iodate did not change its speciation. Migration behavior of both iodine species has to be considered as iodide appears to be the less mobile species due to fast binding to SOM, but with the potential risk of mobilization when oxidized to iodate. |
Databáze: | OpenAIRE |
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