富钾页岩矿粉的酸浸提钾

Extracting potassium from mineral powder of potassium-rich shale by sulfuric acid

为了有效利用矿样的难溶性钾资源,针对湖北宜昌地区的富钾页岩,首先直接用硫酸浸取提钾,然后在页岩中加入一定质量配比的磷矿后再用硫酸浸取提钾.考查了矿样质量配比,硫酸质量分数,硫酸用量,反应时间对钾提取的影响.结果表明:在常温常压下钾岩矿直接用硫酸提钾,浸出率只有12%左右;富钾页岩矿粉与磷矿矿粉按一定比例混合后用硫酸得到较好的钾的浸出率.最佳的工艺条件为:富钾页岩矿与磷矿的质量比为0.8,硫酸用量为4 m L/g,硫酸质量分数为60%,常温下反应2 h,钾的浸出率为73%左右.

To utilize the slightly soluble potassium resources effectively from the potassium-rich shale produced in Hubei Province,we first extracted potassium by sulfuric acid directly,then added a mass ratio of phosphorite in the ore and extracted potassium by sulfuric acid.The influences of mass ratio,concentration of sulfuric acid,dosage of sulfuric acid and reaction time on extracting potassium were studied.The results show that the potassium leaching rate is 12% using sulfuric acid directly under the room temperature and the normal atmospheric pressure; the higher leaching rate is got while extracting potassium from potassium-rich shale with phosphorite as the additive by sulfuric acid; the optimum conditions for the leaching are sulfuric acid concentration of 60%,mass ratio of 0.8,sulfuric acid of4 g/ml,reaction time of 2 h,finally the leaching rate of potassium reaches about 73%.