A New Synthesis of Hollandite. A Possibility for Immobilization of Nuclear Waste
Na-buserite exchanges readily its Na+ for other ions. When Ba2+ is incorporated, dehydration to Ba-birnessite occurs. Subsequent heating at temperatures of ca. 500-800 °C in air in a furnace leads within hours to a structural rearrangement and to nucleation of hollandite. The latter is a tectomanga...
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| Main Authors: | , |
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| Format: | Article |
| Language: | deu |
| Published: |
Swiss Chemical Society
1981-02-01
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| Series: | CHIMIA |
| Online Access: | https://www.chimia.ch/chimia/article/view/9510 |
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| Summary: | Na-buserite exchanges readily its Na+ for other ions. When Ba2+ is incorporated, dehydration to Ba-birnessite occurs. Subsequent heating at temperatures of ca. 500-800 °C in air in a furnace leads within hours to a structural rearrangement and to nucleation of hollandite. The latter is a tectomanganate with Ba2+ ions sitting in a tight fit in tunnels. The content of these tunnels is not exchangeable. The new way of synthesis is a topotactical reaction and leads to less finely divided products than previous preparation methods starting from MnO4- solutions. The new synthesis is also much easier than previously used hydrothermal methods. The product of analytical composition BaMn2III Mn6IV O16 provides a means for immobilization of waste ions of appropriate size (≈ 1.4 Å) and is thermally stable up to 800 °C.
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| ISSN: | 0009-4293 2673-2424 |