MECHANOCHEMICAL SYNTHESIS AND CHARACTERIZATION OF AONANOPOWDER

Al2O, nanopowders were synthesized via mechanochemical method using AlCls and CaO as raw materials. The effect of thermal treatment on the structural evolutions and morphological characteristics of the nanopowder was investigated using X-ray diffractometery, transmission electron microscopy, scanning electron microscopy, differential thermal analysis and Rietveld refinement. The results showed that the average crystallite size of Al2O3 was less than 100 nm up to around 1200 °C. The activation energy for Al2O, nanocrystallite growth during calcinations was calculated to be about 23.104 and 30.121 kJ/mol for eta and kappa alumina respectively while aAl2O, it was 8.380 and 34.120 kJ/mol at temperatures up to 1200 °C and higher than 1200 °C respectively.

Keywords:

Alumina nanoparticles , Mechanochemical synthesis , Characterization methods , Activation energy , Phase transformation