太阳能电池含氟废酸制备氟硅酸钠工艺研究

Preparation of sodium fluorosilicate from fluorine-containing waste acid in solar cell industry

以太阳能电池行业含氟废酸为原料,通过投加沉淀法白炭黑将废酸中的氢氟酸转化为氟硅酸,再投加硫酸钠将氟硅酸转化为氟硅酸钠,实现废酸氟的资源化。在白炭黑过量20%,反应温度室温,反应时间30 min,氢氟酸转化率达99.50%。硫酸钠过量20%,反应时间30 min,氟硅酸的去除率大于98%。所得氟硅酸钠产品纯度大于99%,达到氟硅酸钠优等品要求。

In this paper,fluorine-containing wasteacid in solar cell industry as raw material,by adding precipitated silica hydrofluoric acid in waste acid converted into fluorosilicic acid,then added sodium sulfate convert the fluosilicate acid into sodium fluosilicate.At the silica exceeds 20%,reaction temperature of room temperature,reaction time of 30 minutes,the conversion of hydrofluoric acid reached 99.50%.Sodium sulfate excess 20%,reaction time 30 minutes,fluorosilicic acid removal rate is more than 98%.The purity of sodium fluosilicate product is more than 99%,which meets the requirements of sodium fluosilicate superior product.