汞(Ⅱ)-碘化钾-次甲基蓝分光光度法测定汞(Ⅱ)的研究和应用

Study on Determination of Mercury (Ⅱ) with the Reaction System of Mercury(Ⅱ)-Iodide-Methylene Blue

本文研究了汞(Ⅱ)-碘化钾-次甲基蓝(MB)体系的分光光度特性和最适宜的显色条件,在PVA_(124)吐温-80活性剂存在下,在0.024～0.036mol/L硝酸介质中,显色体系在560nm处有最大吸收,其摩尔吸光系数ε_(560)为4.3×10~5mol^(-1)·cm^(-1)·L;缔合物组成为Hg(Ⅱ):I^-:MB=1:4:2;0～10μg/50mL范围内,服从比耳定律。方法快速、简便、灵敏度高,应用于工业废水中汞的测定,结果令人满意。

The spectrophotometric properties and the colour reaction conditions of mercury-iodide-methylene blue(MB) ion associate system in the presence of polyvinyl alcohol (PVA_(124)) and Tween-80 have been studied. The system has a maximum absorption at 560nm in 0.024～0.036 mol/L HNO_3 medium. The apparent molar absorptivity is 4.3×10~5L·mol^(-1)·cm^(-1) at 560nm. The composition ratio is Hg(Ⅱ): iodide: MB=1:4:2. Beer's law is obeyed in the range of 0～10μg/50mL for mercury. The method is sensitive,simple and rapid and has been successfully applied to the determination of Hg in industrial waste waters.