一种利用冰晶石母液回收氟硅酸钠的方法

A method to recover sodium fluosilicate from cryolite pregnant liquor

砂状冰晶石母液是由粘土盐卤法工艺生产砂状冰晶石时副产的酸性溶液。本文研究了以砂状冰晶石母液和氟硅酸为原料回收氟硅酸钠的生产方法。本工艺采用在常温下向砂状冰晶石母液中加入一定量的氟硅酸,经搅拌、结晶、过滤、洗涤、干燥制得氟硅酸钠的方法。回收氟硅酸钠后的砂状冰晶石母液因钠离子含量比较低,可用于生产二水氯化钙或聚合氯化铝铁产品。本工艺循环利用砂状冰晶石母液和磷肥行业副产氟硅酸法生产氟硅酸钠,具有生产成本低、资源循环利用、节能环保等特点。

Sandy cryolite pregnant liquor is an acid solution -byproduct when sandy cryolite is produced with clay bittern method. The paper studies the method to sodium fluosilicate from cryolite pregnant liquor and fluosilicic acid, by which sodium fluosilicate is prepared after fluosilicic acid is added into sandy cryolite pregnant liquor under ambient temperature and the slurry is mixed, crystallized ,filtrated ,washed and dried. After the sodium fluosilicate is recovered, the sandy cryolite pregnant liquor containing lower sodium ion may be used in production of dihydrate calcium chloride or polyaluminium chloride iron product. The method has the features of lower production cost,recireulation of resources,saving energy and friendly environment.