| Issue |
J. Phys. IV France
Volume 07, Number C1, Mars 1997
7th INTERNATIONAL CONFERENCE ON FERRITES
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|---|---|---|
| Page(s) | C1-87 - C1-88 | |
| DOI | https://doi.org/10.1051/jp4:1997124 | |
J. Phys. IV France 07 (1997) C1-87-C1-88
DOI: 10.1051/jp4:1997124
Optimal Iron Oxides for Obtaining Hexaferrites
J. Dufour1, R. Latorre1, C. Negro1, F. López-Mateos1, E.M. Alcalá2 and A. Formoso31 Dpto. Ingeniería Química, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid, Spain
2 Dpto. Fisica de Materiales, Facultad de Ciencias Fisicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid, Spain
3 Dpto. Metalurgia Primaria y Reciclado de Materiales, Centro Nacional de Investigaciones Metalúrgicas, Avda. Gregorio del Arno, n° 8, 28040 Madrid, Spain
Abstract
Presently, the ferrites industry consumes large amount of iron oxides obtained by spray roasting of steel pickling liquors. The
aim of this paper is to propose the synthesis of optimal iron oxides by oxyprecipitation of steel pickling liquors in order to obtain Ba-hexaferrite with
high magnetic properties using the ceramic process. As a raw material, it was used sulphuric liquors with iron concentration
of 43 g/l. The studied variables for the oxyprecipitation step were temperature, pH, stirring speed, flow of oxidizer to obtain goethite and
magnetite. The samples were characterized by XRD and SEM. These oxides were wet milled with barium carbonate and the mixture was
calcined in order to obtain Ba-hexaferrite. A VSM was used for determine the magnetic properties and the morphology was studied by XRD
and SEM. With these results five iron oxides were selected and the conditions of the ceramic process (calcination temperature and time)
for obtaining hexaferrite were optimized versus Hc.
© EDP Sciences 1997