Molten Salt Synthesis and Formation Mechanism of Plate-Like MgAl_2O_4 Spinel

摘要

Plate-like Magnesium Aluminum spinel (MgAl_2O_4, MA) with octahedral structure was synthesized using Al_2O_3 plate-like particles and MgO powders as raw materials in the molten salt of LiCl, KC1 or NaCl, respectively. The results indicated that the molten salts accelerated the formation of MA spinel, 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 similar to that of original plate-like Al_2O_3 particles. The growth mechanism of plate-like MgAl_2O_4 spinel with octahedral structure should be governed by "template formation mechanism" accompanied with "dissolution-precipitation mechanism".