Mullitization kinetics from kaolinite incorporating nanometric Ba and Ca fluorides Article uri icon

abstract

  • The work presents the kinetic effect of nanometric BaF2 and CaF2 particles on kaolinite to mullite transformation. The kinetics were evaluated from dilatometric data using two different non-isothermal procedures: conversional model-fitting method and diffusional sintering analysis. From experimental data, the activation energy of mullite formation calculated from sintering (942 kJ/mol) and from conversional method (910 kJ/mol) were in good agreement with those values reported by other authors (mean value 1030 kJ/mol). After incorporation of 3 mol%25 of nanometric BaF2 and CaF2 in kaolinite and applying both analytical procedures, lower activation energies for mullite formation were obtained, assigning to the transformation the value of 635 kJ/mol for kaolinite/BaF2 and 428 kJ/mol for kaolinite/CaF2 composites. © 2015 Elsevier Ltd. and Techna Group S.r.l. All rights reserved.

publication date

  • 2015-01-01