从Pt—Ir合金废料中分离提纯铂和铱

Separation and Purification of Platinum and Iridium from Scraps of Pt-Ir Alloys

Pt—Ir合金废料分离提纯的工艺是交流电化溶解,合金溶解,溶液转化体系,钾盐沉淀、硼氢化钠还原直接得到粗铂。经一次分离,粗铂中含Ir0.01～0.4％,粗铱中含Pt1％。最佳分离条件:溶液中Pt—Ir浓度70g/L;钾盐的加入量为理论量的165％,体系转化二次,粗铂、粗铱提纯后,铂的纯度99.99％,直收率97～98％,铱的纯度99.9％,直收率93～94％。

A method for separation and purification of platinum and iridium from Pt-Ir alloy scraps is reported. Characteristics of this process are ① The scraps of Pt-Ir alloy are dissolved with electrochemical solution in concentated acid solution at a fast speed. ② Impurity platinum can be obtaned directly by changing solution system, precipitating with sylvite, and reducing with NaBH_4. The optimum conditions are the concentration of Pt and Ir in the solution being 70g/L, the adding of sylvite being 65% more than the theoretical amount, and the chaning of solution system being for twice. ③ The purity of product platinum is 99.99%, recovery is 97.0～98.0%. The purity of iridium is 99.9%, recovery is 93～94%.