高灵敏显色反应—RhB^+—Ir(Ⅲ)—SnCl_3^-—PVA体系测定铱

Spectrophotometric Determination of Iridium in ihe System of RhB^+—Ir(Ⅲ)—SnCl_3^-—PVA

通过对在聚乙烯醇存在下,RhB^+—lr(Ⅲ)一SnCl_3^-显色反应体系的研究,提出了一个光度法测定铱的方法。显色物的灵敏度为ε_(585nm)=4.2×10~6和2.4×10~6,相应符合比尔定律的铱的浓度范围为0～0.20μg/25ml和0.2～0.8μg/25ml。所拟方法已用于某些贵金属物料中铱的测定。所测结果与它法对应相符。

A very high sensitive method for the spectrophotometric determination of iridium with trichloro-stannate ( II ) and rhodamine B in the presence of polyvinyl alcohol has been developed. The coloured substance exhibits a mixium absorption at 585nm.When the range of the content of iridium is 0-0.2ug /25m1 and 0.2-0.8ug/25ml in which Beer's law is obeyed, the molar absorptivities are 4.2X105 and 2.4X105 respectively. The method is applicable for the determination of iridium in some precious metal samples. The comparison results of the present method with the other methods showed to be in good agreement.