Molten Salt Synthesis and Formation Mechanism of Plate-Like MgAl₂O₄ Spinel

Abstract

Plate-like Magnesium Aluminum spinel (MgAl2O4) with octahedral structure was synthesized using Al2O3plate-like particles and MgO powders as raw materials in the molten salt of LiCl, KCl or NaCl, respectively. The Results indicated that the molten salts accelerated MA formation, and LiCl was more effective than KCl and NaCl, which may be attributed to the higher solubility of MgO in the former than in the latter two. The outline shape of MA spinel product phase was the same as that of original plate-like Al2O3particles. The growth mechanism of plate-like MgAl2O4spinel particles with octahedral structure should be governed by “template formation mechanism” accompanied with “dissolution-precipitation mechanism”.