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Fe, 26]
Published in Alina Kabata-Pendias, Barbara Szteke, Trace Elements in Abiotic and Biotic Environments, 2015
Alina Kabata-Pendias, Barbara Szteke
Iron occurs at several oxidation states, from +2 to +6, of which the most common is +3. Geochemistry of Fe is very complex and is largely determined by the easy change of the state of oxidation, and easy chemical reactions with other metals. Its behavior is also closely linked to the cycling of O, S, and C. Iron-ore minerals are mainly ferric oxides (hematite), hydrated ferric oxides (goethite), and various other minerals, such as siderite, pyrite, and ilmenite. Bog iron ores are small deposits of siderite, resulting from the precipitation of soluble Fe(HCO3)2 in lakes, swamps, and shallow shelf regions.
Wetlands
Published in M. Sengupta, Environmental Impacts of Mining, 2018
Natural wetlands can remove iron (Fe), manganese (Mn), and other metals from acid drainage. Accumulations of limonite, known as bog iron, were mined long ago as a source of Fe. Similarly, mixed oxides of Mn, called wad or bog manganese, are the product of less acidic wetland removal processes. These wad deposits contain mixed oxides of Fe, copper (Cu), and other metals.
Sedimentary Rocks
Published in F.G.H. Blyth, M. H. de Freitas, A Geology for Engineers, 2017
F.G.H. Blyth, M. H. de Freitas
Bog-iron ores are impure limonitic deposits which form in shallow lakes and marshes, as in Finland and Sweden today. The deposition of the iron may be due to the action of bacteria or algae. The ores were much used in the early days of iron-smelting.
Chemistry in 17th-Century New England
Published in Ambix, 2022
In addition to useful overviews of the religious, political, social, and economic factors at play in seventeenth-century New England history, Patterson’s work includes several sections that would particularly appeal to chemists. The section on the Braintree ironworks provides details on bog iron and the chemical processes of charcoal stacking. The chapter on New London discusses graphite, antimony, and saltpetre – not just as historical commodities, but also as understood by modern chemistry. Historians who are just beginning their exploration of New England alchemy will find that the book provides a good, if short, overview, with references to most of the more important scholarship on alchemy from the last century. The use of Winthrop to structure the book is a good choice for guiding the reader through the historical events and trends important to alchemy and makes good use of the more recent scholarship on Winthrop’s alchemical endeavours.
The role of SiO2 and silica-rich amorphous materials in understanding the origin of uncommon archeological finds
Published in Materials and Manufacturing Processes, 2020
As a short summary of recognized processes and produced materials, we have the following statements: 1 – Recrystallization of SiO2 rich glassy phase(s) and nanocrystalline quartz can be recognized in knapped stone tools, and was a basic reaction of the manufacturing process.2 – Temperature and relative heating duration of accidentally burned materials can be determined from the ratio of silica-rich glass and silicate minerals.3 – Dominance of cristobalite (both cubic – high temperature, and tetragonal – low-temperature form) and K-silicates indicate glass production residues.4 – Beneficiation of bog iron ore was a necessary step to remove the high quartz content; otherwise, Fe-extraction would not have been possible.5 – Metallurgical slags can be distinguished from any other SiO2 rich product/byproduct.Extracting the pattern of amorphous contribution also allows for the recognition and classification of glasses with different origins.
Biogas purification processes: review and prospects
Published in Biofuels, 2023
J. E. Castellanos-Sánchez, F. A. Aguilar-Aguilar, R. Hernández‐Altamirano, José Apolonio Venegas Venegas, Deb Raj Aryal
Zdeb [83] studied the removal efficiency of hydrogen sulfide from biogas with bog iron ore, incorporated into the biological desulfurization in the wastewater treatment plant ‘Hajdów’. The study used sulfur-oxidizing bacteria Thiobacillus (thiooxidans and thioparus) and Sulfolobus. The raw biogas had between 55 to 80% methane, < 40% carbon dioxide, and up to 1110 ppm H2S. Comparing the results of H2S removal, it was observed that using only bog iron ore eliminates between 75.1 and 89.9%, while the biological process improves efficiency between 97.6 and 99.5% (Table 8). Therefore, using sulfur-oxidizing bacteria is efficient for biogas upgrading.