Preparation and Characterization of Al2O3-Kaolin Composite Porous Ceramic Used as Ceramic Membrane Support
The high sintering temperature of Al2O3 is the main reason of the high cost of the common ceramic membrane supports. To decrease the sintering temperature, kaolin and talc were chosen as sintering aid because the reaction between kaolin, talc and Al2O3 generates cordierite. The Al2O3-cordierite porous ceramic samples were sintered in the range of 1450~1510°C. The microstructure and the bending strength of the samples were characterized. The results show that the content of kaolin is no more than 8%, the bending strength of the porous ceramic sintered at 1460°C and 1510°C are 77MPa and 153MPa, respectively. The further increases of the kaolin content result in the decrease of the bending strength and the porosity. The needle-like cordierite locates in the neck of Al2O3 grains. The reaction between kaolin and Al2O3 contributes to increasing the sintering velocity. The ceramic support using cordierite as sintering aid has the acid/alkali corrosion resistance in some degree.
Yiwang Bao, Danyu Jiang and Jianghong Gong
Q. B. Chang et al., "Preparation and Characterization of Al2O3-Kaolin Composite Porous Ceramic Used as Ceramic Membrane Support", Key Engineering Materials, Vol. 544, pp. 56-59, 2013