Study of aluminium oxide from high-alumina refractory ceramics by thermoluminescence

Abstract

This work is focused on the study of the thermally stimulated blue emission of aluminium oxide (Al 2 O 3 ) that has been removed from twenty different high alumina-rich refractory bricks. The glow curve sensitivity of several alumina grains are defined by (i) a maximum centred at about 165°C that can be deconvoluted into two first order kinetic peaks at 157 and 177°C and (ii) a broad structure over 200-220°C that suggests a continuous trap distribution system. The isolated grains, analysed by means of X-ray diffraction, are composed of 43% of alumina (Al 2 O 3 ), 22% of mullite [72% of Al 2 O 3 and 28% of SiO 2 ], 12% of leucite (KAlSi 2 O 6 ) and 23% of sillimanite [Al 2 O 3 ⋅SiO 2 ]. The sample characterization has been performed using X-ray fluorescence and scanning electron microscopy.