Mechanical Properties of TiO2-Kaolin FGM Produced by Progressive Lamination Method for NOx Reduction


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Mechanical properties of TiO2-Kaolin Functionally Graded Materials (FGMs) that combined TiO2 and Korean kaolin (Al2Si2O5(OH)4) in a graded distribution were experimentally investigated. TiO2 is an excellent photocatalysis material, however, it does not have the mechanical strength sufficiently. Therefore, FGMs were used as the photocatalysis materials with mechanical strength. To improve the mechanical properties, Korean kaolin was selected as a binder. Bulk FGMs were produced by vacuum filtration and compression involving wet filtration, mechanical compression and sintering. By this process, it is easy to control the thickness of FGMs. The porosity in FGM depends on the content of TiO2. The porosity in FGM decreases with increasing pressure of the compressor. The shrinkage decreases with increasing compression pressure at all ratios of TiO2 and kaolin. The materials have almost no shrinkage at 10 MPa. The bending strength and the Young’ modulus depends on content of TiO2. The bending strength of material was found to be approximately 2.5 MPa for 10 MPa compression pressure at TiO2 side. The bending strength and the Young’ modulus increases with increasing compression pressure. These results indicate that kaolin particles are useful to improve the strength of FGM. These properties of FGM, such as porosity, shrinkage, mechanical strength, etc., can be controlled by content of TiO2 and compression pressure. Based on an optimal design of production conditions, FGMs were developed for the nitrogen oxides (NOx) removal. The NOx reduction increases with increasing compression pressure. NO of 11.7 mg/m2h was removed under present conditions. The sintering temperature ensured the optimal removal of NOx was 800 oC. After NOx removal test, the FGMs were found to be free from erosion due to photocatalysis. And kaolin particles do not interfere in photocatalysis effect of TiO2. It can be concluded that TiO2-Kaolin FGM have a possibility for application to the air purification.



Materials Science Forum (Volumes 492-493)

Edited by:

Omer Van der Biest, Michael Gasik, Jozef Vleugels




Y. Uchida et al., "Mechanical Properties of TiO2-Kaolin FGM Produced by Progressive Lamination Method for NOx Reduction ", Materials Science Forum, Vols. 492-493, pp. 293-298, 2005

Online since:

August 2005




[1] N. Hayashi, K. Taka, S. Watanabe, T. Ishikura, Y. Uchida, S. Higa, D. Dykes, P.L. Fang, K. Azuma and M. Shirato: Journal of Fluid Machinery Vol. 25 (1997), p.198.

[2] Yoshihisa Uchida, J. Yamada, S. Watanabe, N. Hayashi, H. Furuhashi, Y. Uchida, Y. P. Kathuria and G. Touchard: Journal of Electrostatics Vol. 40 & 41(1997), p.741.


[3] S. Watanabe, Y. Hobo, N. Hayashi, Y. Uchida, D. Dykes and G. Touchard: Materials Science Forum Vol. 308-311 (1999), p.555.


[4] S. Watanabe, R. Yamashita, S. Katoh, N. Hayashi, Y. Uchida, S. Higa, D. Dykes and G. Touchard: Functionally Graded Materials in the 21st Century (Kluwer Academic Publishers, 2001, p.157.

[5] S. Watanabe, Yoshihisa Uchida, N. Hayashi, Y. Uchida, S. Higa, D. Dykes and G. Touchard: Proceedings of the 3rd International Symposium on Non-Thermal Plasma Technology for Pollution Control (2001), p.278.

[6] Yoshihisa Uchida, J. -N. Liu, Y. Wada, S. Higa, N. Hayashi, H. Furuhashi and Y. Uchida: Journal of Ecotechnology Research Vol. 8 (2002), p.140.

[7] Yoshihisa Uchida, N. Hayashi, S. Higa and Y. Uchida: Proceedings of the 20th International Japan-Korea Seminar on Ceramics (2003), p.169.

[8] Yoshihisa Uchida, A. Nakajo, H. Suzuki, S. Higa, Y. Uchida and N. Hayashi: Proceedings of Ninth World Filtration Congress, No. 146-8 (2004), p.146. 8. 1.