Side reaction in the hydrogen and carbothermal reductions of BaO and BaCO3: The role of an infinitesimal amount of water
| Autor: | Ichiro Takeuchi, Jung Hyun Jeong, Seunghun Lee, Sung Chul Jung, Mijeong Kang, Ju Hyun Oh, Jihun Park |
|---|---|
| Rok vydání: | 2022 |
| Předmět: |
Alkaline earth metal
Thermogravimetric analysis Materials science Hydrogen Inorganic chemistry Side reaction General Physics and Astronomy chemistry.chemical_element Barium hydroxide Metal chemistry.chemical_compound chemistry Carbothermic reaction visual_art visual_art.visual_art_medium General Materials Science Inert gas |
| Zdroj: | Current Applied Physics. 34:19-23 |
| ISSN: | 1567-1739 |
| Popis: | Alkaline earth (AE) metals are irreplaceable ingredients in the synthesis of AE metal-based antiperovskite oxides, and it can be achieved by a chemical reduction of a stable AE metal compound. In this study, hydrogen and carbothermal reduction of BaO and BaCO3 were employed, and we here report an undesirable side reaction creating barium hydroxide (Ba(OH)2) as the product of the reaction with the small amount of water in ultra-high purity inert gas used in the reduction processes. Such side reaction pathways and products are hardly identifiable in a high-temperature reaction; yet, systematic investigations on phase evolutions using X-ray diffraction, IR spectroscopy, and thermogravimetric analysis enabled the detection of Ba(OH)2·xH2O. Unintentional creation of alkaline earth metal oxides in intermediate and subsequent hydration even under a negligible amount of H2O may lead to an unexpected loss of alkaline earth metal element and, consequently, its deficiency in a desired final product. |
| Databáze: | OpenAIRE |
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