DEPAQ与铀（Ⅵ）显色反应的研究及应用

Study on color Reaction of Uranium(Ⅵ) with DEPAQ and Its Application

本文研究了Ｔｒｉｔｏｎ－Ｘ－１００存在的情况下５－（４－二乙氨基苯偶氮）－８－羟基喹啉（ＤＥＰＡＱ）与铀（Ⅵ）的显色反应。结果表明，在ｐＨ７．５～８．５范围内显色剂与铀（Ⅵ）具有较灵敏的反应，配合物的最大吸收波长为５２６ｎｍ，用平衡移动法和斜率比法测得配合物的组成为１：２，表观摩尔吸光系统。为６．２６×１０４Ｌ·ｍｏｌ－１·ｃｍ－１，铀的含量在０～５０μｇ／２５ｍｌ范围内符合比耳定律。在适量的ＣｙＤＴＡ存在下，大多数常见离子不干扰测定。经ＴＢＰ萃取色层分离后，本法用于岩石中微量铀的测定，结果令人满意。

A sensitive color reaction of uranium (Ⅵ ) with 5 - (4 - diethylaminophenylazo ) - 8 hydroxyquinoline (DEPAQ) is investigated in a medium of Triton X- 100 and PH= 7. 5-8. 5.U (Ⅵ ) reacts with DEPAQ to form a stable red complex with a molar ratio of 1: 2. The complex shows a maximum absorption at 526 urn with an apparent molar absorption coefficient of 6.24 × 104 L. mol-1. cm-1. Beer's law is obeyed in the range of 0-50 μg/25 ml. The interference of various foreign ions is investigated. After the separation by tributylphosphorate (TBP) chromatography,the proposed method is applied to the determination of microamounts of wrarium in rocks with satisfactory results.