Publication detail

The kinetics of Al-Si spinel phase crystallization from calcined kaolin

PTÁČEK, P. OPRAVIL, T. ŠOUKAL, F. NOSKOVÁ, M. HAVLICA, J. BRANDŠTETR, J.

Original Title

Type

journal article - other

Language

English

Original Abstract

The crystallization of Al-Si spinel from medium ordered kaolin with high content of kaolinite was investigated using the differential thermal analysis (DTA). The apparent activation energy of the process was evaluated from the dependence of exothermic peak of crystallization on heating rate. Within the applied interval of heating rate (1-40 K min-1) the temperature of peak maximum increases from initial value of 1220.5 K in about 54.2 K. The apparent activation energy of the process 856 +/- 2 kJ mol-1was calculated using the Kissinger equation. The growth morphology of Al-Si spinel crystal was evaluated from the Avrami parameter. The average value of morphology parameter determined within the observed interval of heating rate is 3.08 +/- 0.03. This value indicates that crystallization mechanism of Al-Si spinel phase proceeds by bulk nucleation of the new phase with constant number of nuclei and that the three-dimensional growth of crystals is controlled by the reaction rate on the phases interface.

Keywords

Al-Si spinel; Kaolin; Kaolinite; Heterogeneous kinetics; Thermal analysis

Authors

PTÁČEK, P.; OPRAVIL, T.; ŠOUKAL, F.; NOSKOVÁ, M.; HAVLICA, J.; BRANDŠTETR, J.

RIV year

2010

Released

1. 11. 2010

Publisher

Elsevier

Location

ISBN

0022-4596

Periodical

JOURNAL OF SOLID STATE CHEMISTRY

Year of study

183

Number

State

United States of America

Pages from

2565

Pages to

2569

Pages count

BibTex

@article{BUT50929,
  author="Petr {Ptáček} and Tomáš {Opravil} and František {Šoukal} and Magdaléna {Křečková} and Jaromír {Havlica} and Jiří {Brandštetr}",
  title="The kinetics of Al-Si spinel phase crystallization from calcined kaolin",
  journal="JOURNAL OF SOLID STATE CHEMISTRY",
  year="2010",
  volume="183",
  number="11",
  pages="2565--2569",
  issn="0022-4596"
}