工业硫酸镁制备高纯氧化镁的合成研究

以工业硫酸镁和氢氧化钠为原料，合成氢氧化镁前驱物经煅烧制备高纯氧化镁。研究了净化工业硫酸镁溶液时的pH值大小以及沉镁时氢氧化钠浓度对产品纯度的影响。在确定了精制硫酸镁与氢氧化钠摩尔计量比、陈化时间、煅烧时间的条件下，通过单因素实验和正交试验确定了反应的较佳工艺条件为：硫酸镁的浓度2mol／L，反应温度40℃，反应时间35min，煅烧温度900℃，产物氧化镁的纯度达到99％以上。采用x射线衍射仪和透射电镜对样品进行表征，结果表明：样品粒子平均粒径约为40nm，形貌为类球形，分布较均匀。

Research on Preparation of High-purity MgO by Commercial Magnesium Suffate

The high-purity MgO was prepared by commercial magnesium sulfate and sodium hydroxide. The impact of different pH of commercial magnesium sulfate and sodium hydroxide concentration on the purity of prepared magnesium ox ide were investigated. After the molar ratio both MgSO4 and NaOH, the ageing time and the calcination time were determined, and the optimum processing conditions of precipitation were obtained by single factor and orthogonal experiments. The conditions as follows： the concentration of the MgS04 was 2mol/L, the reaction temperature was 40 ℃, the reaction time was 30 min and the calcination temperature was 900℃. Under these conditions, the purity of MgO was more than 99%. The morphology of the magnesia was characterized by X-ray diffraction（XRD）and transmission electron microscopy（TEM）. The results indicated that sample particle distribution uniformity, and their average size was about 40 nm.