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Intrinsic reduction kinetics of cobalt- and nickel-titanates by hydrogen

Published online by Cambridge University Press:  31 January 2011

I. Arvanitidis
Affiliation:
Division of Theoretical Metallurgy, Royal Institute of Technology, S-100 44 Stockholm, Sweden
A. Kapilashrami
Affiliation:
Division of Theoretical Metallurgy, Royal Institute of Technology, S-100 44 Stockholm, Sweden
Du Sichen
Affiliation:
Division of Theoretical Metallurgy, Royal Institute of Technology, S-100 44 Stockholm, Sweden
S. Seetharaman
Affiliation:
Division of Theoretical Metallurgy, Royal Institute of Technology, S-100 44 Stockholm, Sweden
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Abstract

The isothermal reduction of synthetic CoTiO3 and NiTiO3 in hydrogen (1 atm) was investigated using thermogravimetric analysis technique in the temperature range, 928–1287 K (CoTiO3) and 884–1387 K (NiTiO3). Shallow beds of fine titanate powders were reduced by hydrogen at a high flow rate. Quenched samples were analyzed by scanning electron microscopy. The rates of the reaction of the titanates with H2 were very fast during the reduction of Co2+, Ni2+, or Fe2+ ions into metals. The reduction of the remaining titanium oxide was very slow. The activation energy for the reduction of CoTiO3 by hydrogen to Co and TiO2 was evaluated to be 151 ± 1 kJ/mol, and the activation energy for the reduction of NiTiO3 by hydrogen to Ni and TiO2 was evaluated to be 153 ± 1 kJ/mol. The study was complemented by hydrogen reduction of synthetic TiO2 (rutile). The results were also compared with the hydrogen reduction of FeTiO3.

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Articles
Copyright
Copyright © Materials Research Society 2000

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References

REFERENCES

1.Bansal, N.P., Simons, R.N., and Farell, D.E., Appl. Phys. Lett. 53, 603 (1988).CrossRefGoogle Scholar
2.Ulman, M., Tinnemans, A.H.A, Mackor, A., Aurian Blajeni, B., and Halmann, M., Int. J. Sol. Energy 1(3), 213 (1982).CrossRefGoogle Scholar
3.Semsarzadeh, M.A., J. Polym. Sci., Polym. Lett. Ed. 23(4), 183 (1985).Google Scholar
4.Kesson, S.E., Sinclair, W.J., and Ringwood, A.E., Nucl. Chem. Waste Manage. 4, 259 (1983).Google Scholar
5.Ringwood, A.E. and Kelly, P.M., Philos. Trans. R. Soc. A319, 63 (1986).Google Scholar
6.Sridhar, S., Sichen, D., and Seetharaman, S., Z. Metallkd. 85, 616 (1994).Google Scholar
7.Sridhar, S., Sichen, Du, and Seetharaman, S., Metall. Mater. Trans. 25B, 391 (1994).CrossRefGoogle Scholar
8.Bustnes, J.A., Sichen, D., and Seetharaman, S., Metall. Mater. Trans. 26B, 547 (1995).CrossRefGoogle Scholar
9.Bustnes, J.A., Sichen, D., and Seetharaman, S., Design Fundamentals of Composites, Intermetallics and Metal/Ceramic Systems, TMS Annual Meeting, Anaheim, CA, Feb 1996.Google Scholar
10.Kapilashrami, A., Arvanitidis, I., and Sichen, D., High Temp. Mater. Processes 15, 73 (1996).CrossRefGoogle Scholar
11.Readey, D.W., Ceram. Eng. Sci. Proc. 13, 301 (1992).CrossRefGoogle Scholar
12.Iida, Y., J. Jpn. Soc. Powder Metall. 6, 55 (1957).CrossRefGoogle Scholar
13.Goldman, D.B., J. Am. Ceram. Soc. 66, 811 (1983).CrossRefGoogle Scholar
14.Sichen, Du and Seetharaman, S., Metall. Trans. 23B, 317 (1992).CrossRefGoogle Scholar
15.Lynch, D.C., and Bullard, D.E., Metall. Mater. Trans. 28B, 447 (1997).CrossRefGoogle Scholar
16.Yankin, A., Vikhreva, O., and Balakirev, V., J. Phys. Chem. Solids 60, 139 (1999).CrossRefGoogle Scholar
17.Chattopadhyay, G. and Kleykamp, H., Z. Metallkd. 74, 182 (1983).Google Scholar
18.Baker, H., Alloy Phase Diagrams, SM Handbook Vol. 3 (The Materials Information Society, 1992).Google Scholar
19.Bustnes, J.A., Metall. Mater. Trans. 28B, 613 (1997).CrossRefGoogle Scholar