Solid state sintering of lime in presence of La2O3 and CeO2
- 60 Downloads
The sintering of lime by double calcination process from natural limestone has been conducted with La2O3 and CeO2 additive up to 4 wt.% in the temperature range 1500–1650° C. The results show that the additives enhanced the densification and hydration resistance of sintered lime. Densification is achieved up to 98.5% of the theoretical value with La2O3 and CeO2 addition in lime. Grain growth is substantial when additives are incorporated in lime. The grain size of sintered CaO (1600°C) with 4 wt.% La2O3 addition is 82 μm and that for CeO2 addition is 50 μm. The grains of sintered CaO in presence of additive are angular with pores distributed throughout the matrix. EDX analysis shows that the solid solubility of La2O3 and CeO2 in CaO grain is 2.9 and 1.7 weight %, respectively. The cell dimension of CaO lattice is 4.803 %C. This value decreases with incorporation of La2O3 and CeO2. The better hydration resistance of La2O3 added sintered lime compared to that of CeO2 added one, is related to the bigger grain size of the lime in former case.
KeywordsSintered lime cation vacancy hydration resistance microstructure
Unable to display preview. Download preview PDF.
- Boynton R S 1980Chemistry and technology of lime and limestone (New York: John Wiley and Sons) p. 18Google Scholar
- Carr K, Evans L J, Leonard L A and Richardson 1968Trans. Br. Ceram. Soc. 64 473, 493Google Scholar
- Gropyanov V M and Novikov V L 1923Ogneupory 9 11Google Scholar
- Heslop R B and Jones K 1976Inorganic chemistry, A guide to advanced study (Amsterdam: Elsevier Scientific Publishing Co.)Google Scholar
- Hubble D H 1969J. Am. Ceram. Soc. Bull. 48 618Google Scholar
- Nadachowski F 1975Interceram 24 42Google Scholar
- Samsonov G V 1973The oxide hand book (New York: Plenum Press) 2nd ed. p. 178Google Scholar
- White J 1972Bol. Soc. ESP Ceram. 11 11Google Scholar
- Williams P, Sunderlan M and Briggs G 1982Iron Making & Steel Making 9 150Google Scholar