Chemical reduction of hematite by sodium borohydride.

Resende, Valdirene Gonzaga de; Costa, Geraldo Magela da; Grave, Eddy De; Dantas, Lucien

Chemical reduction of hematite by sodium borohydride.

Date

2005

Authors

Resende, Valdirene Gonzaga de

Costa, Geraldo Magela da

Grave, Eddy De

Dantas, Lucien

Abstract

Well-crystallized hematite was suspended in water and treated at roomtemperature (RT) with sodium borohydride. The product of the reaction is a highly magnetic black powder, which is stable at RT. The NaBH4 treatment converts about half of the hematite to an amorphous Fe–B alloy and to a small fraction of sub-micron sized, amorphous metallic-Fe nodules. Heating at 400°C of this composite has resulted in the crystallization and/or oxidation of more than half of the amorphous Fe–B phase to α-Fe and Fe3O4 and B2O3, respectively. After treatment at 800°C, the metallic Fe and the amorphous Fe–B have completely vanished, and the resulting product consists of hematite and FeBO3 embedded in the matrix of α-Fe2O3.

Keywords

Fe–B alloy, Hematite, Sodium borohydride, Mössbauer

Citation

RESENDE, V. G. de et al. Chemical reduction of hematite by sodium borohydride. Hyperfine Interactions, Netherlands, v. 165, n.1-4, p. 113-119, 2005. Disponível em: <https://link.springer.com/article/10.1007/s10751-006-9254-0>. Acesso em: 20 abr. 2017.