Microbial reduction of Fe(III)-bearing clay minerals in the presence of humic acids
| Autor: | Guangfei Liu, Ruofei Jin, Baiqing Liu, Yiying Pu, Jiti Zhou, Zhanming Gao, Qiu Shuang, Jing Wang |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Shewanella
Mineralogy Anthraquinones 010501 environmental sciences engineering.material 010502 geochemistry & geophysics 01 natural sciences Anthraquinone Ferric Compounds Article chemistry.chemical_compound Soil Adsorption Dissolution Humic Substances 0105 earth and related environmental sciences Minerals Multidisciplinary Soil chemistry Nontronite Montmorillonite Biodegradation Environmental chemistry Illite engineering Clay Aluminum Silicates Clay minerals Nuclear chemistry |
| Zdroj: | Scientific Reports |
| ISSN: | 2045-2322 |
| DOI: | 10.1038/srep45354 |
| Popis: | Both Fe(III)-bearing clay minerals and humic acids (HAs) are abundant in the soils and sediments. Previous studies have shown that bioreduction of structural Fe(III) in clay minerals could be accelerated by adding anthraquinone compound as a redox-active surrogate of HAs. However, a quinoid analogue could not reflect the adsorption and complexation properties of HA, and little is known about the effects of real HAs at environmental concentration on bioreduction of clay minerals. Here, it was shown that 10–200 mg l−1 of natural or artificially synthesized HAs could effectively stimulate the bioreduction rate and extent of Fe(III) in both iron-rich nontronite NAu-2 and iron-deficient montmorillonite SWy-2. After adsorption to NAu-2, electron-transfer activities of different HA fractions were compared. Additionally, Fe(II) complexation by HAs also contributed to improvement of clay-Fe(III) bioreduction. Spectrosopic and morphological analyses suggested that HA addition accelerated the transformation of NAu-2 to illite, silica and siderite after reductive dissolution. |
| Databáze: | OpenAIRE |
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