超细Al(OH)_3的粒度控制研究

Study on the Control of Particle Size of Superfine AI(OH)_3 Powder

采用铝酸钠种子分解法制备超细Al(OH)_3。用X射线衍射仪(XRD)表征了样品的晶相组成,用扫描电子显微镜(SEM)观察了样品的形貌,用激光粒度分析仪测定样品的粒度分布。研究了NaOH浓度、NaOH/Al(OH),摩尔比,分解温度,分解时间、晶种率和搅拌速率等因素对AL(OH)_3的粒度的影响。结果表明:NaOH浓度越高,分解温度越低,NaOH/Al(OH),摩尔比越小,得到的Al(OH),颗粒的粒度越小。试验条件为:NaOH浓度180 g/L,NaOH/Al(OH),摩尔比1.15,分解温度40℃,分解时间26 h,晶种率8%,搅拌速率200 rpm时,氢氧化铝颗粒的平均粒度为2.89μm。

Superfine Al（ OH）3 powder is prepared by NaEAl2O4 seed decomposition. The crystalline phase of sample is analyzed by X-ray diffraction （XRD）. Its surface morphology is analyzed by scanning electron microscopy （SEM）. And the particle size distribution of the sample is characterized by laser particle size analyzer. The influences of sodium hydroxide con- centration, the molar ratio of sodium hydroxide and aluminum hydroxide, decomposition temperature, decomposition time, seed rate and stirring rate on the particle size of A1 （OH） 3 are investigated. The results show that higher concentration of sodium hydroxide, lower decomposition temperature, lower the molar ratio of sodium hydroxide and aluminum hydroxide, the smaller the particle size of superfine Al（OH） 3 powder are prepared. The experiment conditions are： NaOH concentration is 180 g/L, the molar ratio of sodium hydroxide and aluminum hydroxide is 1.15, the decomposition temperature is 40℃, decomposition time is 26 h, seed rate is 8% , and stirring rate isl00 rpm, then the average particle size of Al（OH） 3 particles is 2.89 μm.