催化动力学分光光度法测定镨和钐

Kinetic Spectrophotometric Determination of Trace Praseodymium and Samarium

在盐酸介质中,痕量稀土元素镨和钐催化双氧水氧化碘化钾生成单质碘,单质碘可使次甲基蓝褪色,基于此建立了催化动力学分光光度法测定稀土元素镨和钐的新方法.方法的线性范围分别为5.1×10-6mol/L～5.1×10-5mol/L、5.1×10-6mol/L～5.1×10-5mol/L,检出限分别为2.75×10-6mol/L和2.44×10-6mol/L.该方法用于含稀土的纳米材料中镨和钐的分析测定,结果满意.

A new kinetic spectrophotometric procedure for the analysis of micro amount of Pr or Sm in material has been described. This method was based on its catalytic effect of Pr(Ⅲ) or Sm(Ⅲ) on the redox reaction of methylene blue-hydrogen peroxide-potassium iodide system in hydrochloric acid medium. The action of Pr(Ⅲ) or Sm(Ⅲ) in this system was studied. The linear range of determination of both Pr and Sm is 5.1×10^(-6)mol/L～5.1×10^(-5)mol/L with detection limits of 2.75×10^(-6)mol/L(Pr) and 2.44×10^(-6)mol/L(Sm), respectively. The procedure was proved to be suitable in terms of selectivity for the micro amount of Pr and Sm in material.