硫酸亚铁电流滴定法测定铱化合物中铱量

Determination of iridium in iridium compounds by ferrous sulfate current titration method

采用硫酸亚铁电流滴定法测定铱化合物中铱元素含量,对化合物的溶解方法、试剂用量、吹气条件、共存元素干扰及测定过程影响因素等进行了研究并获得了最佳实验条件。结果表明,样品经过盐酸-过氧化氢高温高压处理转化后,可使铱价态统一为Ir(Ⅳ),再用硫酸亚铁电流滴定法测定。该方法可以避免某些铱化合物在常规溶解过程中由于铱价态不一致而导致的检测结果失真。方法的测定范围10%~60%,加标回收率99.75%~100.13%;四氯化铱、三氯化铱、氯铱酸、氯铱酸铵、醋酸铱、乙酰丙酮铱6种铱化合物的测定精密度均在0.10%~0.25%之间,均能很好满足铱化合物中高量铱测定的精密度和准确度要求。

The content of iridium in iridium compound was determined by ferrous sulfate current titration.In this paper,studied dissolution method,amount of reagents,coexisting elements and influencing factors of the determination process of iridium compounds and obtained the best experiment conditions.The results showed that the samples were transformed by hydrochloric acid-hydrogen peroxide in high temperature and high pressure treatment,to unify the valence state of iridium as iridium(Ⅳ),then determined by ferrous sulfate current titration.This method can avoid the distortion of detection results which caused by some iridium compounds in conventional dissolved the inconsistent iridium valence state.The determination range of the method were 10%~60%;the recovery rates of standard addition were 99.75%~100.13%.The precision was 0.10%~0.25%of IrCl_(3),IrCl_(4),H_(2)IrCl_(6),(NH_(4))_(2)IrCl_(6),Ir(OAC)_(3),Ir(acac)_(3)which can meet the precision and accuracy requirements of high iridium compounds.