Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-03T05:33:36.580Z Has data issue: false hasContentIssue false
  • English
  • Français

Some Comments on the Production of Medium Sized Spherical Particles by Anion and Water Extraction Variant of Sol-Gel Process

Published online by Cambridge University Press:  15 February 2011

A. Deptula ,
W. Łstoke;ada ,
T. Olczak  and
A. Chmielewski
A. Deptula
Affiliation:
Institute of Nuclear Chemistry and Technology, Warsaw, Poland
W. Łstoke;ada
Affiliation:
Institute of Nuclear Chemistry and Technology, Warsaw, Poland
T. Olczak
Affiliation:
Institute of Nuclear Chemistry and Technology, Warsaw, Poland
A. Chmielewski
Affiliation:
Institute of Nuclear Chemistry and Technology, Warsaw, Poland
Get access

Abstract

Medium sized spherical particles (with diameters below 100 μm) of ceramic materials (Al203 and Al203 +8%TiO2) were produced in the following steps: (1) preparation of concentrated hydroxide sols of cations by extraction of anions using Primene JMT, (2) formation of sol emulsion in 2-ethylhexanol-1 containing various amounts of surfactants (EH), (3) gelation of emulsion drops by extraction of water with partially dehydrated EH, (4) non-destructive thermal treatment. Principal properties of the sol depend on the temperature of the extraction process. For preparation of lowanionic sols a two step extraction process, separated by digestion of the aqueous phase at boiling point, was necessary. It was found that the parameters of emulsion formation as well as the properties of the sols significantly influence the particle size distribution. It was concluded that lowering of the sol- EH interracial tension by the surfactant does not influence the process. On the contrary the “anti-clustering” effect of surfactants is essential for preparation of perfect spherical powders. The thermal decomposition of gels to oxides is determinant for densities, specific surface area and carbon content. Medium sized spherical powders are free flowing. The compactibility and sinterability of those powders are poor. However drastic reduction of particle size by milling (connected with their transformation to irregular shape) significantly improves the sinterability.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 372: Symposium W1 – Hollow and Solid Spheres and Microspheres--Science and Technology , 1994 , 83
Copyright
Copyright © Materials Research Society 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Deptula, A., Majani, C., Sol- gel Processes and their Applications, ENEA Report No. RT/TIB/86/25, Roma 1986.Google Scholar
2. Deptula, A., Rebandel, J., Drozda, W., Łada, W., Olczak, T., Production of Spherical Powders of Inorganic Compounds by Water Extraction Variant of Sol-gel Process in Better Ceramic Through Chemistry V, edited by Hampden-Smith, M.J., Klemperer, W.G. and Brinker, C.J., (Mat. Res. Soc. Symp. Proc. 270, Pittsburgh, PA, 1992) p. 277.Google Scholar
3. Xu, R., Pope, E.J.A. and Mackenzie, J.D., J. Non- Crystalline Solids 121, 45 (1990).Google Scholar
4. Clinton, S.D., ORNL Raport TM-2163 (June 1968).Google Scholar
5. Deptufa, A., Łada, W., Olczak, T. and. Bartolomeo, A. Di, Preparation of Pt/A12O3 Catalysts by Sol-gel Process and its application to uranyl ion reduction in Better Ceramic Through Chemistry VI, edited by Cheetham, A.K., Brinker, C.J., Mecartney, M.L. and Sanchez, C. (Mat. Res. Soc. Symp. Proc. 346, Pittsburgh, PA, 1994) p.661.Google Scholar
6. Deptula, A., Majani, C., Bartolomeo, A. Di and Carewska, M., Material Science Monographs, Vol. 14 (Elsevier Science Publisher B.V. Amsterdam 1982) p.219.Google Scholar
7. Majani, C., Deptula, A., Carewska, M., Bartolomeo, A. Di and Przytycka, R., Material Science Monographs, Vol. 14 (Elsevier Science Publisher B.V. Amsterdam 1982) p.227.Google Scholar
8. Deptula, A., Carewska, M., Croce, F., Scrosati, B. and Majani, C., Caramics Today- Tommorow's Ceramics, edited by Vincenzini, P. (Elsevier Science Publisher B.V. Amsterdam 1991) p.2253.Google Scholar
9. Deptula, A., Carewska, M.,Olczak, T., Lada, W. and Croce, F., J. Electrochem. Soc. 140, 2294 (1993).Google Scholar
10. Kaliszewski, M.S. and Heuer, A.H., J.Am. Ceram. Soc. 73,1504 (1990).Google Scholar