中文摘要：

用菱镁矿和工业纯硫酸来制备七水硫酸镁,进一步脱水得到无水硫酸镁。以无水硫酸镁和木炭粉为原料,经高温煅烧制备高纯氧化镁。研究反应物的配比、煅烧温度、煅烧时间以及粒径对产品纯度的影响。采用X线衍射和扫描电镜对样品进行表征。通过单因素实验确定的最佳工艺条件为：硫酸镁和炭粉的最佳配比8：1,煅烧时间2 h,煅烧温度800℃,粒径109μm。研究结果表明：在最佳工艺下,样品纯度达到99%,粒径分布介于109～700μm之间,单分子表面为多孔蓬松高比表面。

英文摘要：

Magnesium sulfate heptahydrate prepared by magnesite and commercial sulfuric acid was dehydrated to prepare anhydrous magnesium sulfate.High-purity magnesia was obtained by commercial magnesium sulfate and charcoal powder.The influences of the reactants ratio,calcination temperature and time and diameter of particles on the purity of prepared magnesium oxide were investigated.The optimum processing parameters of precipitation were obtained by single factor experiments.The morphology of the magnesia was characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）.The results indicate that the optimum conditions are as follows： the ratio of magnesium sulfate to charcoal powder is 8：1,the calcination time is 2 h,the calcination temperature is 800 ℃,and the grain diameter is 109 μm.The sample particle purity can reach as high as 99%,and the distribution falls in between 109？700 μm.The single molecule surface with high specific surface area is porous and fluffy.