Study on Preparation of Mullite Powder Using Fly Ash by Mechanochemical Method

Abstract:

This paper studies the structural changes of the mixture of fly ash and A1₂O₃ grinded by planetary ball mill . By investigating the structure of the ground product by SEM, XRD and FT-IR, the mechanism of mullite formation is discussed. The crystal structure of the mixture was destroyed by the grinding of planetary ball mill, and with the grinding time increases, the specific surface area of the mixture increases as well. And this leads to the decrease of bond energy, the increase of the internal energy and the decrease of the activation energy. After this process,uniform mixture and direct formation of signal phase mullite can be obtained from the mixture grinded for 30 hours and calcined at 1150°C for 2 hours and the temperature for mixture ungrinded needs to reach 1450°C.

• Periodical: Applied Mechanics and Materials (Volume 318)
• Pages: 326-330
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.318.326
• Online since: May 2013
• Authors: Lei Zhang, Qun Yu Chen, Ding Gao
• Keywords: Fly Ash (FA), Mechanochemical Method, Mullite Powder

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