轻烧氧化镁及其前驱体的制备  

Preparation of Ccalcining MgO and its precursor

作　　者：任宏瑞[1,2] 陈镇[2] 党杰[2] 吴玉龙[2,3] 杨明德[2] 陈津[1] 胡湖生[2] 

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024 [2]清华大学核能与新能源技术研究院,北京100084 [3]精细陶瓷北京市重点实验室,北京100084

出　　处：《盐业与化工》2012年第9期18-22,27,共6页Jounral of Salt and Chemical Industry

基　　金：国家"十一五"科技支撑重点项目(No.2008BAB35B05)

摘　　要：以水氯镁石(MgCl2·6H2O)为镁源,Na2CO3为沉淀剂,利用沉淀法得到碳酸镁水合物,然后通过低温煅烧得到高纯氧化镁。研究了沉淀过程中反应温度和初始反应溶液的pH值对轻烧氧化镁及其前驱体的组成和晶型的影响,结果表明在室温～323 K时,得到了棒状的三水碳酸镁;在333 K～363 K之间,得到了碱式碳酸镁。333 K温度下,pH值在9.5～12.5范围内,得到形状不同的碱式碳酸镁颗粒。在1 073 K下煅烧上述前驱体得到高纯度(99%以上)的MgO,为后续高纯镁砂的制备提供了优质原料,同时为盐湖镁资源制备高纯镁砂工艺的进一步深入研究奠定了基础。Various compositions and morphologies of magnesium carbonate hydrates have been synthesized by the reaction of MgC12 with Na2 CO3. By calcining method, high purity MgO can be got. The effect of the reaction temperature and pH value of the initial reaction solution in the pre- cipitation process on the composition and morphology of magnesium oxide and its precursor was re- searched. The results show that, the rod -like MgCO3 ~ 3H20 can be obtained from room tempera- ture to 323 K. With the reaction temperature （ 333 ~ 363 K） increasing, 4MgCO3 ~ Mg （OI-I） 2 ＂ 4H20 became the preferred precipitation. At 333 K, pH =9.5 -12.5, Various morphologies parti- cles can be got with a formula of 4MgCOa ~ Mg （OH）2 ＂ 4H20. High -purity （over 99% ） MgO can be obtained by calcinations at 1 073 K, which provides high grade raw material for the prepara- tion of high purity magnesia, And it lays foundations for further research of the preparation process of high - purity magnesia using salt lake resource as material.

关 键 词：轻烧氧化镁 前驱体 碱式碳酸镁 三水碳酸镁 

分 类 号：TQ132.2[化学工程—无机化工]