汞(Ⅱ)-碘化物-结晶紫体系的共振瑞利散射光谱及其分析应用研究

A Study on the Resonance Rayleigh Scattering Spectrum of Mercury (Ⅱ) -Iodide-Crystal Violet System and Its Analytical Application

研究了汞(Ⅱ)-碘化物-结晶紫体系的共振瑞利散射(RRS)光谱．实验结果表明,存0．02 mol／L的H2SO4溶液中,[HgI4]2-与结晶紫在水相中由于静电引力和疏水作用力形成蓝色的离子缔合物时,产生相应的散射光谱, 其最大RRS波长分别位于345 nm和510 nm．在0-0．4 μg／mL范围内汞(Ⅱ)浓度与散射强度(△I)成正比．该法灵敏度高,选择性较好,操作简便,可直接用于水体中痕量汞(Ⅱ)的测定．

The spectra of resonance Rayleigh scattering of mercury（ Ⅱ ）-iodide-crystal violet system have been investigated. The results show that, Hg（Ⅱ） reacts with Ⅰ- to form an anionic complexes [HgI4]^2- , and [HgI4]^2- further reacts with crystal violet to form an ion-association complex [CV]2 [HgI4] in 0.02 mol/L H2SO4 solution, results in a significant enhancement of the resonance Rayleigh scattering（RRS）, and its maximum RRS peaks are at 345 nm and 510 nm. The RRS intensity is proportional to the concentration of mercury（ Ⅱ） in the range of 0-0.4 μg/mL. The method has high sensitivity, the detection limit for mercury.（ Ⅱ ） is 13.6 ng/mL. The method has good selectivity and it can be applied to the determination of trace amounts of mercury（ Ⅱ ） in environmental water samples.