학술논문

Formation and kinetics of porous cordierite from fly ash.
Document Type
Article
Source
Chinese Journal of Geochemistry. 2008, Vol. 27 Issue 4, p395-400. 6p. 2 Black and White Photographs, 2 Diagrams, 2 Charts, 6 Graphs.
Subject
*SINTERING
*OSMOSIS
*CORDIERITE
*FLY ash
*DYNAMICS
*CERAMICS
*ADSORPTION
*ISOSTATIC pressing
Language
ISSN
1000-9426
Abstract
Porous cordierite ceramics were prepared from a mixture of coal fly ash and basic magnesium carbonate at 1100–1350°C. Porosity, flexural strength and thermal expansion coefficient of the samples sintered at 1300°C were estimated to be 26%, 65 MPa and 4.21×10−6/°C, respectively. The kinetics of the formation progress was investigated by stepwise isothermal dilatometry (SID) accompanied with XRD, SEM and porosity measurement. It was found that the isothermal shrinkage data from SID could be well analyzed to get kinetic parameters according to the empirical rate equation developed by Makipirtti-Meng, dY/dt = nk( T) Y(1 − Y)( Y/1 − Y) n/1, where Y is the fractional shrinkage during the sintering process and n is a dimensionless component. The apparent activation energy Δ E values for 900–1000°C and 1050–1150°C were 1294 and 1778 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]