Mg - Al Spinels

Magnesium oxide is used as raw material in the production of magnesium aluminate spinels, typically used in the manufacture of basic refractory bricks and linings, in castable systems and aluminium refractory bodies. The spinels are either produced by mixing of powder ingredients, shaping into briquettes and sintering or by fusing ingredients in granular form in electric arc furnaces. Both caustic calcined and hard-burned magnesium oxide grades may be used, with special requirements in SiO₂ and CaO content, reactivity and grain size, depending on the application.

A special application is the production of spinel-based catalyst supports typically used in fuel catalytic cracking. See also Catalysts.