锆与二溴硝基偶氮氯膦的显色反应及应用研究

Study on Colour Reaction of Zirconium with DBNCPA and Its Application

研究了在Ｈ＿２ＳＯ＿４介质中，锆与二溴硝基偶氮氯膦（ＤＢＮＣＰＡ）体系光度测定微量锆的新方法。络合物的最大吸收峰在６４０ｎｍ，试剂的最大吸收峰在５４０ｎｍ，对比度Δλ＝１００ｎｍ。表观摩尔尔吸光系数ε＿（６４０）＝４．５２×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）．锆含量在０～２０μｇ／２５ｍｌ范围内遵守比尔定律。方法用于铝合金中锆的测定，结果满意。

The colour reaction of Zr with DBNCPA has been studied.It is shown that the red complex is formed in 1 mol·L￣(-1) H_2SO_4 solution. Its maximum absorption is located at 640 nm. The molar absorptivity ε_(640) is 4.52×10￣4L· mol￣(-1)· cm￣(-1)·Beer's law isobeyed in the range of 0～20μg/25 ml for Zr.The composition ratio of Zr to DBNCPA in the complex is 1/2.The method has been applied to the determination of trace amountsZr in aluminium alloy with favorable sensitivity and accuracy.