熔盐法制备岩层形貌氧化镁粉体的研究

以MgCl_2·6H_2O、CaCO_3和LiCl为原料,采用熔盐法制备了岩层形貌MgO粉体.借助热重-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,430 ℃保温3 h热处理,产物中有MgO生成,600 ℃保温3 h热处理,产物经无水乙醇洗涤后,全部为MgO晶体;原料在650 ℃下保温3 h热处理,用水浸泡得到的氢氧化镁为不规整的片状形貌,分解为氧化镁后变成颗粒状形貌,粒径介于0.1～0.6 μm之间;EDTA-PEG溶液浸泡得到的氢氧化镁为四面体形貌,分解为氧化镁后为岩层形貌,大部分在顶角处有缺损,最大边长可达1.5 μm,表层粘附着少量颗粒状氧化镁,表面不平整.

Study on the Layered Rock Configuration MgO Powder Made by Molten Salt Synthesis

Layered rock configuration MgO powders were prepared through molten salt synthesis with MgCl_2·6H_2O, CaCO_3 ,LiCl as raw materials.They were studied by using XRD and TEM while reactants were investigated by TG-DSC and XRD.The results indicated that MgO was formed at 430 ℃ calcined for 3 h.When calcined at 600 ℃, only MgO product existed in the resultant after washed by Ethanol. If raw materials calcined at 650 ℃ for 3 h,Mg(OH)_2 powders soaked by water were non-regular flakes.They changed into non-regular granular shapes when decomposed to MgO with 0.1-0.6 μm in diameter. On the other side, Mg(OH)_2 powders soaked by PEG-EDTA solution were tetrahedrons.They changed into layered rock configurations with vertex defected when decomposed to MgO,which brim were up to 1.5 μm in length.Linked by some granular,MgO were non-smooth surface.