熔盐法制备镁铬尖晶石粉体的研究

Study on Magnesia-Chromate Powders Made by Molten Salt Synthesis

以MgCl2.6H2O、CaCO3和Cr2O3为原料,在NaCl、KCl复合熔盐介质中合成了MgCr2O4粉体。通过热重-差示扫描热量计(TG-DSC)、X射线衍射仪(XRD)、场发射扫描电子显微镜(SEM)等手段对反应过程及产物进行了分析和表征,结果表明,在CaCO3、MgCl2.6H2O、Cr2O3原料在反应过程中生成了MgO,800℃热处理后MgO与Cr2O3反应生镁铬尖晶石;温度的升高和保温时间的延长有利镁铬尖晶石的生长及发育,随着热处理温度的升高和保温时间的延长,镁铬尖晶石晶体结晶程度增大,粉体粒径增大。

The MgCr2O4 powder was synthesized by the medium of compound fused salts called NaCI, KCI through such materials as MgCI2·6H2O, CaCO3 and Cr2O3. According to methods of TG-DSC, XRD and SEM, we＇d analyzed and characterized that reaction process. The result showed that the materials of MgC12·6H2O, CaCO3 and Cr2O3 were synthesized into MgO and then MgO reacts with Cr2O3 to produce magne sioehromite by being heated about 800 ℃. It proved that the rise in temperature and the extension in soaking time benefit growth of magne siochromite in the form of higher crystal density and wider powder diameter.