新试剂二溴甲基偶氮羧胂与锆显色反应的研究及其应用

Study on the Colour Reaction of zirco-nium with a New Reagent Dibromo-p-methyl-carboxyarsenazo(DBMCA)and ItSApplication

在１．６ｍｏｌ／Ｌ盐酸介质中，锆与试剂二溴甲基偶氮羧胂（ＤＢＭＣＡ）形成１：３的蓝色配合物，λ＿（ｍａｘ）＝６４０ｎｍ，表观摩尔吸光系数ε＝３．７×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），锆量在０～１５μｇ／２５ｍＬ范围内符合比耳定律。本法的优点是可在三倍量的铪存在下直接测定锆，且操作简便，反应快速，有较高的选择性。应用于铜合金中微量铬的测定，取得了令人满意的结果。

Aspectrophotometric determinationmethod for microamount of zirconium with anew chromogenic reagent DBMCA is de-scribed. In 1.6 mol/L HCl medium thereagent reacts with zirconium to form a 3:1blue complex, The molar absorptivity is 3.7×10￣4L·mol￣(-1)·cm￣(-1) at 640nm, Beer's lawis obeyed for 0～15μg of zirconium in 25mLsolution. The advantage of the method isthat zirconium is not interfered by 3-fold amount of hafnium. The present method issimple,rapid and selective. The method hasbeen used to determine zirconium in copperalloys with satisfactory results.