离子交换分离富集极谱法连续测定金、铂、铱、铑、钌

来源期刊：黄金2010年第6期

论文作者：张辉 唐杰 张凯

文章页码：57 - 59

关键词：极谱法； 分离富集； 贵金属； 连续测定

Key words：polarography； seperation and preconcentration； noble metal； simultaneous determination

摘    要：研究了在同一份试液中极谱法连续测定Au、Pt、Ir、Rh、Ru的体系。首先在1mol/L的氢氧化钠溶液中,于原点电位-0.20V处扫描作Au的峰电流-质量浓度曲线;然后,改变溶液pH值,在0.75mol/L硫酸-1.5%氯化铵-1.5×10^-3mol/L六次甲基四胺-0.003%硫酸肼体系中,于原点电位-0.78V处扫描作Pt、Ir、Rh的峰电流-质量浓度曲线;最后,加入2.25mol/L硫酸-4%氯化铵-2.5×10^-4mol/L硫脲测定Ru。在选定的实验条件下得到令人满意的分析结果,线性范围分别为:0.1～1000μg/mL(Au);8×10^-5～6.4×10^-3μg/mL(Pt、Ir);1.6×10^-5～1.28×10^-3μg/mL(Rh);1.14×10^-4～3.42×10^-3μg/mL(Ru)。实际样品通过阴离子交换树脂分离富集后进行分析,回收率在93%～106%之间。

Abstract: In this article,the condition of the system and instrument for the simultaneous determination of Au,Pt,Ir,Rh and Ru in the same solution by polarography is studied.The analysis technological process is as follows: first,the current-mass concentration curve of Au is scanned at the origin potential of-0.20 V in the medium of 1 mol/L NaOH solution;and then pH is adjusted,the current-mass concentration curves of Pt,Ir and Rh are determined at the origin potential of-0.78 V in the systemmofm 0.75 mol/L H2SO4-1.5 % NH4Cl-1.5×10^-3 mol/L (CH₂)₆N₄-3 ×10^-3% N₂H₄·H₂SO₄;finally,Ru is determined by adding 2.25 mol/L H₂SO₄-4 % NH₄Cl-2.5×10^-4 mol/L thiocarbamide.This method is used for geological sample analysis with good results in the selected experimental conditions.The linear ranges of Au,Pt,Ir,Rh and Ru are respectively 0.1-1 000 μg/mL( Au) ,8×10^-5-6.4×10^-3 μg/mL(Pt,Ir) ,1.6×10^-5-1.28×10^-3μg/mL( Rh) and 1.14×10^-4-3.42×10^-3μg/mL (Ru) .Usually,the samples are analyzed after seperation and preconcentration by anion exchange resin and the recovery range is from 93 % to 106 % .