石棉尾矿制备高纯轻质氧化镁

Preparation of High Pure Light Magnesium Oxide by Asbestos Tailings

以石棉尾矿为原料,利用硫酸铵焙烧法制备精致硫酸镁,通过添加碳酸氢钠制备前驱体碱式碳酸镁,将前驱体在不同温度下焙烧得到高纯轻质氧化镁,整个过程实现了石棉尾矿的资源化利用及助剂硫酸铵的循环利用.结果表明:焙烧温度为500℃~800℃时均能得到轻质氧化镁,焙烧温度为600℃和800℃时氧化镁结晶效果最好;随着焙烧温度的增加,氧化镁的晶粒逐渐增大;轻质氧化镁的纯度可达到99.0%.

Ammonium sulfate calcination method is used to extract magnesium from asbestos tailing to get fine magnesium sulfate. Sodium bicarbonate is added for the preparation of the precursor of basic magne- sium carbonate. Then, the high pure light magnesium oxide can be obtained by calcining the precursor at different temperatures. The whole experimental process realizes the resource utilization of asbestos tailing and the cycling of the precursor, ammonium sulfate. The results show that light magnesium oxide can be ob- tained when calcination temperature ranges from 500 ℃ to 800℃. However, the product with best crystal- lization effect is obtained when calcining temperature is at 600 ℃ and 800 ℃ respectively. With the in- crease of calcinatiota temperature, the crystallite size of magnesium oxide increases gradually. The purify of the light magnesium oxide in products is over 99.0 %.