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Journal of Materials Science

, Volume 31, Issue 17, pp 4625–4628 | Cite as

Preparation of barium iron oxides by the oxidation of iron in the Fe-Ba(OH)2-NaOH-H2O-O2 system

  • S. Uchida
  • H. Kashiwagi
  • T. Sato
  • A. Okuwaki
Article

Abstract

Iron was oxidized in the Fe-Ba(OH)2-NaOH-H2O-O2 system at elevated temperatures. Fe3O4 and α-FeOOH were formed in the absence of oxygen. On the other hand, hexagonal plate-like particles of BaFe12O19, 1.0–4.3 μm diameter, were formed as single phase by the oxidation of iron in Ba(OH)2 and NaOH mixed solutions at 250–300°C and above 1.0 MPa oxygen. The diameter of the particle significantly depended on the NaOH concentration. Additives such as CO 3 2− , SO 4 2− and CH3COO promoted the grain growth of BaFe12O19.

Keywords

Oxidation Iron Fe3O4 Hexagonal Barium 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Chapman & Hall 1996

Authors and Affiliations

  • S. Uchida
    • 1
  • H. Kashiwagi
    • 1
  • T. Sato
    • 1
  • A. Okuwaki
    • 1
  1. 1.Department of Molecular Chemistry and Engineering, Faculty of EngineeringTohoku UniversitySendaiJapan

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