Bioelectrochemical Changes during the Early Stages of Chalcopyrite Interaction with Acidithiobacillus Thiooxidans and Leptospirillum sp
| Autor: | Jessica Viridiana García Meza, María Irene López Cázares, Olga Araceli Patrón Soberano |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
lcsh:QE351-399.2
Inorganic chemistry chemistry.chemical_element 02 engineering and technology sulfur reduced species 020501 mining & metallurgy medicine Reactivity (chemistry) Dissolution hydrophobicity biooxidation lcsh:Mineralogy biology Chalcopyrite Chemistry microbiology Metallurgy Biofilm Geology Acidithiobacillus thiooxidans 021001 nanoscience & nanotechnology Geotechnical Engineering and Engineering Geology biology.organism_classification Sulfur chalcopyrite 0205 materials engineering visual_art biofilms visual_art.visual_art_medium Ferric 0210 nano-technology Bacteria medicine.drug |
| Zdroj: | Minerals; Volume 7; Issue 9; Pages: 156 Minerals, Vol 7, Iss 9, p 156 (2017) |
| ISSN: | 2075-163X |
| DOI: | 10.3390/min7090156 |
| Popis: | A bioelectrochemical study of charge transfer in the biofilm–chalcopyrite interface was performed to investigate the effect of surficial reduced sulfur species (RSS), in the form of non-stochiometric compounds or polysulfides (Sn2−) and elemental sulfur (S0) on a biofilm structure, during the earliest stages (1, 12 and 24 h) of chalcopyrite biooxidation by Acidithiobacillus thiooxidans alone and adding Leptospirillum sp. The surface of massive chalcopyrite electrodes was exposed to the bacteria, which were analyzed electrochemically, spectroscopically, and microscopically. At the studied earlier times, charge transfer and significant differences in the biofilm structure were detected, depending on the presence of Leptospirillum sp. acting on A. thiooxidans biofilms. Such differences were a consequence of a continuous chalcopyrite pitting and promoting changes in biofilm hydrophobicity. A. thiooxidans modifies the reactive properties of RSS and favors an acidic dissolution, which shifts into ferric dissolution when Leptospirillum sp. is present. A. thiooxidans allows H+ and Fe3+ diffusion, and Leptospirillum sp. enables to surpass the charge transfer (reactivity) barrier between the mineral interface and the ions. The observed changes of hydrophobicity on the interface are associated to ions and electrons activity and transfer. Finally, a model of S0 biooxidation by A. thiooxidans alone or with Leptospirillum sp. is proposed. |
| Databáze: | OpenAIRE |
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