Abstract
The behavior of Colombian magnesite in producing spinel was evaluated by comparing its physical properties and XRD-determined phases with spinel derived from pure magnesium oxide. Spinel finds utility as a refractory in cement and steel industries (Henry, 1997), as an abrasive material, an electric circuit substrate, ceramic membranes, and recently in dental restorations. Spinel forms through a thermally activated reaction above 1100ºC between magnesia and alumina. Two compositions were selected based on phase diagrams and studied. Reactants with a particle size smaller than 10 mm were dry pressed and sintered at 1650ºC. The presence of silica in the starting mineral and excess magnesia added facilitated sintering.
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References
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