高性能磷酸盐玻璃原料(高纯KH_2PO_4)的制备

Purification of KH_2PO_4 as a phosphate glass raw material with high performances

用离子交换法制备了高纯KH2PO4（其中杂质Fe^3＋,Co^2＋和Ni^2＋的总质量分数小于3×10^-6）.以树脂的吸附容量和再生性能为考察指标,从三种树脂中选出了性能最佳的一种——螯合树脂D751,探讨了溶液pH值、温度、流速等因素对该树脂吸附容量的影响.结果表明提纯KH2PO4的最佳条件为：pH 4.0-5.0,温度20-30℃,流速1 mL/min.在本实验条件下,D751可将工业级KH2PO4中Fe^3＋,Co^2＋和Ni^2＋的总质量分数由23×10^-6降至3×10^-6以下.

A phosphate glass raw material, KH2PO4 with high purity, in which the total weight fraction of Fe^3＋, Co^2＋, and Ni^2＋ is less than 3 × 10^-6, was prepared by ion exchange method. Three types of ion exchange resin were chosen to adsorb the transition metal ions Fe^3＋ , Co^2＋ and Ni^2＋ impurities. The results showed that chelating resin D751 possesses the highest adsorption capacities to the metal ions compared with other resins. The factors, such as pH, temperature, and flow rate that can exert effects on the exchange properties of the D751 were investigated. The optimum conditions for the purification of KH2PO4 are pH4.0-5.0, temperature of 20-30 ℃, and flow rate of 1 mL/min. Under the optimum conditions, the total weight fraction of the metal ions mentioned above was reduced with the D751 from 23×10^-6 to≤3×10^-6 in the salt.