邻苯二酚紫在光度分析测定痕量镉中的应用

Application of Pyrocatechol Violet to Spectrophotometric Analysis of Trace Cadmium Determination

摘要: 研究了邻苯二酚紫在镉-KI-邻苯二酚紫(PV)-溴化十二烷基吡啶(DPB)四元胶束混配物协同增敏显色反应,在pH=5～6的弱酸性条件下,Cd²⁺-PV和KI、DPB形成稳定的配合物,在光度分析中,λ_max=710nm处有最大吸收,摩尔吸光系数ε_max=1.6×10⁶L/(mol.cm).可测定盛水瓷器器皿中镉红釉彩溶解出的痕量Cd²⁺.方法简便、快速,测定结果与火焰原子吸收光度法吻合.

Abstract: A method is proposed by Cadmium-KI-Pyrocatechol Violet-DPB'S micelle for synergistic colour reaction.Cd²⁺-PV and KI,DPB from quaternary complex in a weak acid medium (pH=5～6).In the method of photometric,the maximum absorption wavelength (λ_max) is 710nm;the molar absorption coefficient(ε_max) is 1.6×10⁶L/(mol.cm).The method's sensibility is very high,and selectivity and repetition rate are very good.It can determine tracecadmium from glazed colour of porcelain dish that is dissolved in water.The method is simple and quick.The determined value of this method is identical with AAS.