多波长数据线性组合分光光度测定法同时测定沥青铀矿中的U(Ⅳ,Ⅵ)

Simultaneous Determination of U(Ⅳ) and U(Ⅵ) by Linear Combination of Multi-wavelength Data Spectrophotometry

研究了偶氮氯膦Ⅲ与U(Ⅳ )和U(Ⅵ )显色反应的条件。结果表明 :在酸性介质中 ,U (Ⅵ )和U(Ⅳ )可与偶氮氯膦Ⅲ显色 ,其对应配合物的最大吸收波长分别为 688nm和 670nm ;每 2 5mL样品的线性范围分别为 0～ 70 μg和 0～ 60 μg ,在 62 0～ 710nm波长范围内 ,吸收均具有良好的加和性 ,其摩尔吸光系数均在 10 4 L·mol- 1·cm- 1以上。采用多波长数据线性组合分光光度法处理数据 ,可同时求得U(Ⅵ )和U(Ⅳ )的含量。采用F- C2 O4 2 - PO4 3 - 混合掩蔽体系消除干扰。经对合成水样及沥青铀矿中U(Ⅵ )和U(Ⅳ )的测定 ,证实该法精密度和准确度好。

In the medium of hydrochloric acid,uranium(Ⅳ) and uranium(Ⅵ) can completely colored with chlorophosphonazo Ⅲ. The linear range is 0～70 and 0～60 μg in a sample with a volume of 25 mL for U(Ⅵ) and U(Ⅳ), respectively. The complexes have good additive property in the range of 620～710 nm. Their molar absorptivity are bigger than 10 4 L·mol -1 ·cm -1 . Linear combination of multi wavelength data method is applied to do with the calculation.The results show that the method is simple,rapid,sensitive and accurate.