4,6-二甲氧基-2-嘧啶重氮氨基偶氮苯的合成及其与汞(Ⅱ)的显色反应

Synthesis of 4,6-dimethoxy-2-pyrimidine diazoaminoazobenzene and its colour reaction with mercury(Ⅱ)

合成了4，6-二甲氧基-2-嘧啶重氮氨基偶氮苯（DMPDAA），并研究了它与汞（Ⅱ）的显色反应。结果表明，在TritonX-100存在下，于pH10．5Na2B4O7-NaOH缓冲体系中，Hg（Ⅱ）与4，6-二甲氧基-2-嘧啶重氮氨基偶氮苯形成1：4的红色配合物，其最大吸收波长位于522nm，表观摩尔吸光系数为1．52×10^5L·mol^-1·cm^-1。Hg（Ⅱ）在0—0．80μg／mL范围内符合比尔定律。方法已用于水样中汞的测定。

A new reagent 4,6-dimethoxy-2-pyrimidyl （DMPDAA） has been synthesized and the color reaction of DMPDAA with mercury （ Ⅱ ） has been studied. The results show that DMPDAA reacts with mercury（ Ⅱ ） to form a stable red complex （4： 1） in the presence of Triton X - 100 at pH 10.5. The maximum absorption of the complex is at 522 nm, and the apperent molar absorptivity is 1.52 × 10^5 L·mol^-1 ·cm^-1 . Beer＇s law is obeyed in the range of 0 - 0.80 μg/mL for mercury （ Ⅱ ）. The method was applied to the determination of mercury in waste water with satisfactory results.