高分散氢氧化镁粉体的制备及其影响因素

Preparation of Highly-dispersed Mg(OH)_2 Powders and Influence Factors

以氯化镁为原料,采用氢氧化钠沉淀-水热改性法制备了高分散氢氧化镁粉体,研究了制备过程中的影响沉淀因素.实验结果表明:把温度从40℃提高到90℃、采用往氯化镁溶液中加入氢氧化钠的方式有利于降低溶液过饱和度,制备了平均粒径为0.7μm的六方片状氢氧化镁粉体,采用场发射扫描电镜法分析了其形貌和粒径;氯化镁过量时溶液pH值较低,有利于氢氧化镁沿径向生长,形成结构稳定、高分散性的片状产物,采用X射线粉末衍射法研究了氢氧化镁粉体的晶体结构.

Highly-dispersed Mg(OH)(2) powders were prepared via interaction of magnesium chloride with sodium hydroxide followed with hydrothermal treatment. The influence of process parameters, such as the mixing way of raw materials, temperature, and the mole ratio of magnesium chloride to sodium hydroxide, on the morphology and structure of magnesium hydroxide was investigated. The experimental results indicate that Mg(OH)(2) particles with regular shape and large size are formed at higher temperature (90degreesC) or by adding NaOH into MgCl2 solution. SEM. micrographs show that the size of Mg(OH)(2) particles is about 0.7mum. The excess of MgCl2 is favorable for the formation of Mg(OH)(2) particles with bigger size and stable structure.