Table of Contents
Journal of Powder Technology
Volume 2013 (2013), Article ID 268070, 7 pages
http://dx.doi.org/10.1155/2013/268070
Research Article

Sol-Gel Synthesis of Mullite Starting from Different Inorganic Precursors

1ESIQIE-I P N, UPALM-Zacatenco, Lindavista, 07738 México, DF, Mexico
2Universidad Autónoma Metropolitana, Avendia San Pablo 180, Colonia Reynosa-Tamaulipas, 02200 México, DF, Mexico

Received 17 March 2013; Revised 19 June 2013; Accepted 19 June 2013

Academic Editor: Thierry Barriere

Copyright © 2013 Lucia Téllez Jurado et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Using silicotetraetilortosilicate (TEOS) mixed with aluminum tri-sec-butoxide (TSBAI) or aluminum cloaures mullite ceramics were created by the sol-gel method. The quantities used of each substance were those that led to obtain stoichiometric mullite (3Al2O3·2SiO2). The experimental methodology used for obtaining mullite consisted in: sol-gel synthesis of precursor materials, isothermal treatment of those materials, and characterization of resulting materials. In order to determine the advance of reactions during mullite formation, isothermal treatments between 300°C and 1600°C were performed, keeping the samples at each temperature during 4 h. From XRD results, it may be said that precursor powders originally amorphous start to crystallize in Al2O3 and SiO2 at 1200°C, and the mullite formation starts at 1200°C, with being completed at 1600°C. The use of TSBAI favors the formation of mullite crystals at lower temperature. From SEM observations a microstructure that presents primary mullite with randomly oriented grains of secondary mullite with acicular shapes and sizes that range between 1.25 and 1.50  m long may be determined.