Effect of LiCl·H2O on Sintering Properties of MgO from Bischofite

Abstract

Effect of LiCl·H2O on sintering properties of MgO prepared from natural brine from Qarhan Salt Lake, crystalline bischofite and MgCl2·6H2O(AR) was studied. The results showed that LiCl·H2O of addition exceeded 1 wt% had promoting effect on sintering of magnesia prepared from MgCl2·6H2O(AR). While 1.5 wt% LiCl·H2O was added, the bulk density of magnesia was 3.40 g/cm3, and the relative density was 95.0%. With 0.5 wt% LiCl·H2O, the bulk densities of magnesia prepared from crystalline bischofite and brine were 3.04 and 3.10 g/cm3, and the relative densities increased by 8.4% and 14.8%, respectively. The main mechanism for promoting MgO sintering with LiCl·H2O was that Li2O produced by hydrolysis solubilized in MgO to form solid solutions and oxygen vacancies which were favorable to sintering. The main reasons for promoting sintering of brine magnesia with LiCl·H2O were solid solution and liquid phase sintering, while the main reason was solid solution for magnesia from crystalline bischofite and MgCl2·6H2O(AR).