制备高纯硅所用的碳化稻壳粉的净化研究

研究了碳化稻壳(CRH)的酸浸除杂、超声酸浸除杂,考察了盐酸浓度、酸浸时间、酸浸温度、酸浸液固比和搅拌速度对除杂效果的影响.得到最佳工艺为:CRH粒度在75μm以下、盐酸质量分数为5%、反应时间3h、水浴温度60℃、浸出液固比14∶1、搅拌速度60r/min.在此最佳工艺条件下,CRH中金属元素的总去除率达96.41%、非金属元素的总去除率达66.68%.实验同时也探讨了超声场作用下酸浸时间对杂质去除效果的影响,最终金属元素的总去除率和非金属元素的总去除率分别达到了99.07%和71.77%.

Impurity Remove of Carbonized Rice Husk for Preparing High Purity Silicon

This paper reported on the methods to purify the carbonized rice husk(CRH) including acid leaching and ultrasonic field purification.The effect of mass fraction of hydrochloric acid leaching time,temperature,ratio of leaching liquid to solid and strring speed on impurity remove was investigated.The optimal leaching conditions are CRH particle size less than 75 μm,5% hydrochloric acid,reaction time of 3 h,temperature of 60 ℃,ratio of leaching liquid to solid at 14∶1 and stirring speed of 60 r/min,respectively.Under this optimum condition,96.41% of the metallic elements and 66.68% of the non-metallic elements can be removed.The effect of ultrasonic field was also investigated and the elimination of metallic and non-metallic impurities can reach up to 99.07% and 71.77%,respectively.