撞击流制备高纯纳米氢氧化镁技术研究

Research on preparation technology of high purity nano-sized magnesium hydroxide by impinging stream

采用撞击流反应结晶方法,以青海盐湖水氯镁石为原料,制备了高纯纳米氢氧化镁。研究了各种操作条件对氢氧化镁纯度的影响,并确定了控制因素。并采用X射线衍射(XRD)、透射电镜(TEM)对颗粒形态进行表征。结果表明:可以制备出纯度大于99%、平均粒径为13.5 nm的氢氧化镁。适宜条件:镁离子浓度0.25 mol/L,镁离子与氢氧根浓度比1∶2,反应温度40℃,搅拌时间30 min,搅拌转速400 r/min,撞击流率100 mL/min。

High purity nano-sized magnesium hydroxide was prepared by impinging stream reaction crystallization method using bischofite （ from Chaerhan salt lake, in Qinghai Province ） as raw material. The effects of various operation conditions on the purity of magnesium hydroxide were studied and the control factors of preparation were confirmed. The morphology of the particles was characterized by X-ray diffraction （XRD） and transmission electron microscopy （TEM）. Results showed that purity of prepared Mg（ OH）2 was more than 99% and the mean grain size was 13.5 nm. The optimal conditions are ： the concentration of Mg^2＋ is 0.25 mol/L; the concentration proportion of Mg^2＋ and OH^- is 1： 2 ; the reaction temperature is 40 ℃ ; the agitating time is 30 min; the speed of agitator is 400 r/min; and impinging stream rate is 100 mL/min.