钯钌合金中钌的测定

Spectrophotometric Determination of Ruthenium in Pd-Ru Alloys

研究了钯钌合金中钌的测定方法。在强酸性溶液中（CHCl=5．0mol／L）和在有乙醇作稳定剂时，钌（Ⅲ）可与硫脲形成稳定的蓝绿色配合物；在最大吸收波长（λmax=620nm）处测定，50μg／50ml～250μg／50ml的钌（Ⅲ）符合比尔定律。大量的钯不干扰钌的测定。对钌含量为0．5％的钯钌合金8次测定，相对标准偏差为51％，加料回收率为95％～104％。该方法可用于含钌0．5％～2．5％的钯钌合金中钌的准确测定。

A thiourea spectrophotometric method has been developed for the determination of ruthenium in palladium-ruthenium alloys. The resuh shows that increasing the Pd: Ru ratio to more than 100: 1 does not influence the determination of the ruthenium.The determinate conditions are 5. 0 mol/L (HCl), 12 ml ethanol and 1 gram thiourea in 50 ml solution. One hour or more standingtime is necessary to enable the colour reaction to reach completion at room temperature before the determination is made. Beer's lawis obeyed in the range of 50 μ~250 μg Ru/50 ml. The relative standard deviation (RSD) is about 5. 1% for eight determinations ofRu content in one PdRu sample. The recovery of Ru is about 95%~104%. The method can be easily used for the determination ofRu content between 0. 5% and 2-5% in palladium alloys with satisfactory results.