Kinetic studies on leucite precursors

0340094 - ÚACH 2010 RIV PL eng J - Journal Article
Mrázová, M. - Kloužková, A. - Kohoutková, Martina
Kinetic studies on leucite precursors.
Central European Journal of Chemistry. Roč. 7, č. 2 (2009), s. 205-210. ISSN 1895-1066
R&D Projects: GA MPO 2A-1TP1/063
Institutional research plan: CEZ:AV0Z40320502
Keywords : leucite * crystallization kinetics * hydrothermal
Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass
Impact factor: 1.065, year: 2009

Kinetic studies were performed on two types of leucite precursors. These precursors were prepared using a hydrothermal method at 150 degrees C; the reaction time was 1.5 hours. In order to obtain precursors having different amounts of seed the molarity of KOH was changed. These intermediate products were subsequently calcinated from 5 minutes to 72 hours at temperatures of 850 degrees C, 900 degrees C, 950 degrees C, 1000 degrees C and 1050 degrees C. The crystallinities of the powders were calculated by X-ray diffraction analysis. The crystallization curves for the synthesis of leucite exhibited a typical sigmoidal characteristic. Using different kinetic equations it was found that the Avrami-Erofeev model is the most appropriate to describe the experimental data. Using the Avrami-Erofeev model n reaches an average value of 2.9 which is connected with the three-dimensional growth of nuclei.
Permanent Link: http://hdl.handle.net/11104/0183413