煅烧法制备亚微米氧化铝粉体

Preparation of sub-micron alumina powders by calcination method

以氢氧化铝为原料,将其酸洗预处理在1 200、1 250、1 300、1 350℃煅烧,球磨获得α氧化铝。研究发现:酸洗预处理可以减小氢氧化铝原料中的氧化钠和产物中氧化钠杂质的质量分数,提高最终α相的转化率。煅烧温度影响产物的比表面积,煅烧温度为1 300℃时,制备的α氧化铝具有较高的反应活性,相转化率高达95%。产物球磨6 h后的粒径能达到0.73μm,属于亚微米范围。

Aluminum hydroxides as raw material were calcined at1 200, 1 250, 1 300 and 1 450℃ after pickling washing.Sub-micron alumina were prepared after grinding.The results show that the pretreatment of raw material can reduce mass fractions of Na_2O in raw material and products obviously, and improve the conversion rate of α-phase. The calcination temperature affects the specific surface area of products. The optimum calcination temperature is 1 300℃, at which the α-Al_2O_3 of high conversion rate of 95% and good activity can be obtained.Particles in sub-micron size of 0.73 μm are prepared after grinding for 6 h.