Mineralogy and Characterization of Arsenic, Iron, and Lead in a Mine Waste-Derived Fertilizer
| Autor: | Christopher A. Impellitteri, Kirk G. Scheckel, Aaron G. B. Williams, Thabet Tolaymat |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Iron
Oxide chemistry.chemical_element Mineralogy Sulfides engineering.material Ferric Compounds Arsenicals Arsenic Spectroscopy Mossbauer Ferrihydrite chemistry.chemical_compound Water Supply Galena Anglesite Environmental Chemistry Water Pollutants Fertilizers Arsenopyrite Minerals Temperature Spectrometry X-Ray Emission General Chemistry Tailings Oxygen Lead chemistry visual_art engineering visual_art.visual_art_medium Adsorption Pyrite Iron Compounds Water Pollutants Chemical Environmental Monitoring |
| Zdroj: | Environmental Science & Technology. 40:4874-4879 |
| ISSN: | 1520-5851 0013-936X |
| Popis: | The solid-state speciation of arsenic (As), iron (Fe), and lead (Pb) was studied in the mine waste-derived fertilizer Ironite using X-ray absorption spectroscopy, Mössbauer spectroscopy, and aging studies. Arsenic was primarily associated with ferrihydrite (60-70%), with the remainder found in arsenopyrite (30-40%). Lead was observed almost exclusively as anglesite (PbSO4), with1% observed as galena (PbS). The identification of As in oxidized Fe oxides and Pb as PbSO4 is in disagreement with the dominant reduced phases previously reported and suggests As and Pb contained within the mine waste-derived product are more bioavailable than previously considered. Aging studies in solution result in Ironite granules separating into two distinct fractions, an orange oxide precipitate and a crystalline fraction with a metallic luster. The orange oxide fraction contained As adsorbed/precipitated with ferrihydrite that is released into solution when allowed to equilibrate with water. The fraction with a metallic luster contained pyrite and arsenopyrite. A complete breakdown of arsenopyrite was observed in Ironite aged for 1 month in buffered deionized water. The observations from this study indicate As and Pb exist as oxidized phases that likely develop from the beneficiation and processing of mine tailings for commercial sale. The potential release of As and Pb has important implications for water quality standards and human health. Of particular concern is the quantity of As released from mine waste-derived products due to the new As regulation applied in 2006, limiting As levels to 10 microg L(-1) in drinking water. |
| Databáze: | OpenAIRE |
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