水溶液法制备氧化镁晶须的工艺研究

Preparation Technology of Magnesium Oxide Whishers by Aqueous Solution Method

为了促进氧化镁晶须的规模化生产与工业应用,采用前驱物煅烧法制备了氧化镁晶须。首先以硫酸镁和氨水为原料合成了前驱体碱式硫酸镁晶须,接着将碱式硫酸镁焙烧成氧化镁晶须。探讨了各个工艺条件对产物的影响,探索出最佳的工艺条件为:硫酸镁溶液的浓度为2mol.L-1,水热反应温度160℃,水热反应时间20h。在此条件下制得了前驱物碱式硫酸镁晶须,将碱式硫酸镁晶须焙烧,控制升温速率在5℃.min-1,采取分段升温方式升温至1000℃,灼烧时间6h,即可制得氧化镁晶须。所得的氧化镁晶须表面光滑,直径分布均匀,结晶良好,产率达80%以上。

To promote the scale-up production and industrial application of magnesium oxide（MgO） whiskers,MgO whiskers were prepared by the calcination method of the precursors.The preparation process consisted of the synthesis of a precursor called basis magnesium sulfate whiskers,followed by the heat treatment of the synthesized whiskers.The precursor whiskers were prepared with MgSO4 and NH3·H2O as raw materisls.The influence of each condition to the products was discussed and the best conditions were found as followed： the magnesium sulfate solution concentration was 2 mol/L,the hydrothermal synthesis temperature was 160℃,the hydrothermal synthesis time was 20 h.Under the conditions the basic magnesium sulfate whiskers were prepared.Then the basic magnesium sulfate whiskers were calcinated under the speed of elevated temperature in 5℃/min until the temperature to 1000℃ by separate steps,the calcination time was 6 h,then the magnesium oxide whishers were prepared.MgO whiskers obtained were possessed of smooth surface,uniform size distribution,well crystalline and its productivity could reach to 80%.