安替吡啉偶氮Ⅲ与铈组稀土显色反应的研究

Study on Chromogenic Reaction of Cerium Subgroup Rare Earths with Antipyrylazo Ⅲ

探讨安替吡啉偶氮Ⅲ与铈组稀土离子的显色反应，得出在pH=2的HCl介质中，试剂与铈组稀土元素形成4：1的蓝色络合物，λmax=720nm，ε=8．015×10^4L·mol^-1·cm^-1，稀土含量在0～1．2mg／L，符合比尔定律，选择性较好．在对人工合成样中的铈组稀土含量进行测定时，获得满意的结果。

Chromogenic reaction of cerium subgroup rare earths with antipyrylazo Ⅲ was studied. The results show that in hydrochloric acid media of pH = 2, antipyrylazo Ⅲ reacted with cerium subgroup rare earths to form a 4 ： 1 blue complex, λmax = 720 nm, ε = 8. 015× 10^4 L · mol^- 1· cm^- 1, Beer＇ s law was obeyed in the concentration range of 0 -- 1.2 mg/L for rare earths elements. Antipyrylazo Ⅲ showed good selectivity. The method has been used for the spetrophotometric determination of cerium subgroup rare earths in synthesised sample with satisfactory results.