石棉尾矿酸浸液制备氢氧化镁

Preparation of Magnesium Hydroxide from Acid Leaching Solution of Asbestos Tailings

以石棉尾矿硫酸酸浸液为原料,经过氧化、除铁后得到硫酸镁滤液,采用氨水沉淀法制备氢氧化镁,研究氨水用量、反应温度、反应时间对制备氢氧化镁的影响,并对制备的氢氧化镁样品进行表征。结果表明,利用石棉尾矿酸浸液制备氢氧化镁的适宜工艺条件如下:200 mL酸浸液需要氨水的体积为150 mL,反应温度为70℃,反应时间为40 min;在适宜条件下制备的产物中氢氧化镁的质量分数为93.31%,中位粒径d50为8.42μm,比表面积为35.14 m2/g,白度为98.6%;X射线衍射分析显示氢氧化镁结晶良好。

Taking the sulfuric acid extract of asbestos tailings as raw materials, magnesium hydroxide was prepared by ammonia precipitation method after oxidation and removing iron. The effect of ammonia amount, reaction temperature and reaction time on the preparation of magnesium hydroxide was studied. The magnesium hydroxide samples were characterized. The results show that the optimal conditions of preparing magnesium hydroxide using sulfuric acid extract of asbestos tailings are that the ammonia volume is 150 mL needed by 200 mL acid infusion, the reaction temperature is 70 ℃ and the reaction time is 40 rain. Under the optimal conditions, the purity of prepared magnesium hydroxide is 93.31%, the median particle size d50 is 8.42 μm, the specific surface area is 35.14 m2/g and the whiteness is 98.6%. It can be drawn from X ray diffraction analysis that the magnesium hydroxide well crystallizes.