Kinetic study of ZnFe{sub 2}O{sub 4} formation from mechanochemically activated Zn-Fe{sub 2}O{sub 3} mixtures

Journal Article · Thu Apr 13 04:00:00 EDT 2006 · Materials Research Bulletin

DOI:https://doi.org/10.1016/j.materresbull.2005.10.011· OSTI ID:20891657

Botta, P M ^[1]; Aglietti, E F ^[2]; Porto Lopez, J M ^[1]

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1. Instituto de Investigaciones en Ciencia y Tecnologia de Materiales (INTEMA), J.B. Justo 4302, B7608FDQ Mar del Plata (Argentina)
2. Centro de Tecnologia de Recursos Minerales y Ceramica (CETMIC), Camino P. Centenario y 506, 1897 M.B. Gonnet (Argentina)

The kinetics of ZnFe{sub 2}O{sub 4} formation starting from mechanochemically activated Zn-Fe{sub 2}O{sub 3} powders are studied. Mixtures of metallic Zn and hematite were activated under air atmosphere in a high energy mill and thermally treated at temperatures between 500 and 650 deg. C during several holding times. During the activation, morphological and compositional changes were observed, but ZnFe{sub 2}O{sub 4} formation was not detected. The ZnFe{sub 2}O{sub 4} content in heated samples was determined using quantitative X-ray diffraction analysis. The resulting conversion-time curves were fitted using different kinetic models of solid-state reaction, calculating the kinetic parameters of the studied reaction. The comparison with the conventional synthesis method revealed that the mechanochemical treatment provoked a change of the rate-controlling step and a significant decrease of the activation energy, which was more evident for the more activated mixtures.

• OSTI ID: 20891657
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 4 Vol. 41; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACTIVATION ENERGY
CERAMICS
CHEMICAL PREPARATION
FERRITES
HEMATITE
IRON OXIDES
POWDERS
X-RAY DIFFRACTION
ZINC OXIDES