测定微量铋的分光光度法研究

Study on a Highly Sensitive Spectrophotometric Method for Determination of Bismuth

研究了在KI及非离子表面活性剂存在下用罗丹明B(Rhm B)在水相测定微量铋的高灵敏度方法。配合物的最大吸收(λ_(max))在605nm处,表观摩尔吸光系数ε_(605)=2.88×10~51·mol^(-1)·cm^(-1),在0～10μg Bi^(3+)/25ml范围内符合比耳定律,配合物的组成比Bi^(3+):I^-:Rhm B=1:5:2,大多数常见离子均不干扰。方法的应用范围较广。用于Bi-Sr-Ca-O超导薄膜中的铋的测定,结果较为满意。

A highly sensitive spectrophotometric method for the determination of Bi(Ⅲ) aqueous medium with rhodamine B in the presence of KI and surfactants is developed. The maximum absorption is at 605 nm, and its apparent molar absorptivity is 2.88×10~5. Beer's law is followed over the range of 0 ～10μg/25ml. The ion-associate complex has a composition of (BiI_5) (Rhm B)_2, as established by Asmus and equilibrium method. Most common ions do not interfere. The method is applied to the derterruination of Bi(Ⅲ) in Bi-Sr-Ca-O superconducting film.