硫化镍试金富集-催化光度法测定痕量铑

Kinetic spectrophotometric determination of trace rhodium based on its catalytic effects on the oxidation of methyl red by KIO_4

在铑的硫酸配合物催化高碘酸钾氧化甲基红退色反应的基础上 ,提出了催化光度测定痕量铑的新方法。铑质量浓度在 0～ 0 .1 μg/mL范围内符合比尔定律 ,测定下限为 4× 1 0 - 3μg/mL。对于试样中质量分数为 1 6× 1 0 - 5%Rh的测定 ,RSD为 9 2 %,平均回收率为 89%。测定之前 ,痕量铑用小硫化镍试金富集分离。方法已用于原矿和尾矿中痕量铑的分析。

A new catalytic spectrophotometric method was developed for the determination of trace rhodium based on its catalytic effects on oxidation of methyl red by KIO 4. Beer′s law was obeyed in the concentration range of Rh over 0～0.1 μg/mL with a detection limit of 4×10 -3 μg/mL. The relative standard deviation for the determination of the trace Rh at 1.6×10 -5% in ore was 9.2%(n=5) with recovery of 89%.The trace Rh was concentrated with minified nickel sulfide fire assay before it was determined. The proposed method was applied to the analysis of trace Rh in original ores and tailings.