Effect of calcination on the production of sintered MgAl2O4 by using different local waste Al2O3 powders

Magnesium aluminate spinel is one of the important synthetic minerals which have lots of applications in ceramic, refractories and chemical industries. In this research, two different types of alumina and magnesia sources were used to produce sintered magnesium aluminate spinel. Different compositions were prepared and calcined at 1000, 1100, 1200, 1300 and 1400 °C for 2 h. Calcined spinel samples were characterized by using X-ray diffraction technique, and the amount of formed spinel after calcination was calculated. The physical properties such as bulk density, apparent porosity and the amount of formed spinel in the final sintered samples were also measured. It was shown that by increasing the calcination temperature, the amount of spinel is increased in all of the samples. The maximum amount of spinel was obtained by 1400 °C calcination of the composition that contained calcined magnesia and filter alumina powder 2. It is clarified that locally available waste filter powders can be used as alumina source to produce highly dense sintered spinel.