Thermal and Microstructural Study on Mullite-Based Ceramics from Rice Husk-Alumina Mixtures

Abstract:

This study focuses on the physical and microstructural properties of mullite-based ceramic synthesized by solid-state reaction of rice husk ash (RHA) and alumina (Al₂O₃). Laser Flash analysis (LFA), Field Emission Scanning Electron Microscopy (FESEM) and Energy-dispersive X-ray spectroscopy (EDX) characterized the effects of the mixtures of RHA and Al₂O₃ matrix. The results show that the Al₂O₃rich samples sintered at 1500 °C exhibit the highest thermal diffusivity radiated at 500 °Cwith values varied from 0.258-0.369 mm²/s. The addition of Al₂O₃ (30-60 wt.%) into RHA enhance the crystallization of mullite on the surface of vitreous particles. The presence of diphasic mullite densified the green bodies,and its crystallites size keep increases (400.78-650.52 nm) by theincrement of the sintering temperature (1200-1500 °C). These results suggested that addition of Al₂O₃into RHA enhance the thermal diffusivity as the values closer to the thermal diffusivity of pure mullite and have high potential application as thermal insulation material. The properties of mullite-based ceramics listed above such samples M1, where the composition closes to mullite (3:2) have comparable properties to commercialize mullite ceramics.

• Periodical: Materials Science Forum (Volume 948)
• Pages: 274-278
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.948.274
• Online since: March 2019
• Authors: Rabiatul Adawiyah Abdul Wahab*, Khamirul Amin Matori, Mazlini Mazlan, Maryam Mohammad
• Keywords: Alumina, Mullite, Rice Husk Ash, Sintering, Thermal Diffusivity

References

[1] H. Schneider, J. Schreuer, B. Hildmann, Structure and properties of mullite—A review, J. Euro. Ceram. Soc.28 (2) (2008) 329-344.

[2] J. H. Lee, H. J. Choi, S. Y. Yoon, B. K. Kim, H. C. Park, Porous mullite ceramics derived from coal fly ash using a freeze-gel casting/polymer sponge technique, J. Porous Mat. 20 (1) (2013) 219-226.

DOI: 10.1007/s10934-012-9591-0

[3] J. Pype, B. Michielsen, S. Mullen, V. Meynen, Impact of inorganic waste fines on the structure of mullite microspheres by reaction sintering, J. Eur. Ceram. Soc. 38 (6) (2018) 2612-2620.

DOI: 10.1016/j.jeurceramsoc.2018.01.030

[4] V.A. Mymrin, K.P. Alekseev, E. V. Zelinskaya, N.A. Tolmacheva, R.E. Catai, Industrial sewage slurry utilization for red ceramics production, Constr. Build. Mater. 66 (2014) 368-374.

DOI: 10.1016/j.conbuildmat.2014.05.036

[5] M.F. Serra, M.S. Conconi. M.R. Gauna, G. Suarez, E.F. Aglietti, N.M. Rendtorff, Mullite (3Al2O3·2SiO2) ceramics obtained by reaction sintering of rice husk ash and alumina, phase evolution, sintering and microstructure, J. Asian Ceram. Soc. 4(1) (2016) 61-67.

DOI: 10.1016/j.jascer.2015.11.003

[6] X. Wu, G. Shao, S. Cui, L. Wang, X. Shen, Synthesis of a novel Al2O3–SiO2 composite aerogel with the high specific surface area at elevated temperatures using an inexpensive inorganic salt of aluminum, Ceram. Inter. 42 (1) (2016) 874-882.

DOI: 10.1016/j.ceramint.2015.09.012

[7] V.A. Drebushchak, L.N. Mylnikova, T.N. Drebushchak, V.V Boldyrev, The investigation of ancient pottery, J. Therm. Anal. Calorim. 82 (3) (2005) 617-626.

DOI: 10.1007/s10973-005-0942-9

[8] R, Barea, M.I. Osendi, J.M.F. Ferreira, P. Miranzo, Thermal conductivity of highly porous mullite material, Acta Mater. 53 (11) (2005) 3313-3318.

DOI: 10.1016/j.actamat.2005.03.040

[9] S. Chen, J. Wang, L. Yuan,Q. Li, Composite Design of Low Thermal Conductivity Mullite Brick for Application to Cement Kiln, MATEC Web. Conf. 142 (2018).

DOI: 10.1051/matecconf/201814202008

[10] R. Zhang, C. Ye, B. Wang,Novel Al2O3–SiO2 aerogel/porous zirconia composite with ultra-low thermal conductivity,J. Porous Mat. 25 (1) (2018) 171–178.

DOI: 10.1007/s10934-017-0430-1

[11] B. Hildmann, H. Schneider, Thermal Conductivity of 2/1‐Mullite Single Crystals, J. Am. Ceram. Soc. 88 (10) (2005) 2879-2882.

DOI: 10.1111/j.1551-2916.2005.00530.x