铋-亚硝基R盐-乙基紫体系高灵敏分光光度法测定痕量铋

A Sensitive Spectrophotometry for Determining Trace Bismuth in the System of Bismuth-Nitroso-R Salt-Ethyl Violet

关键词:  铋  亚硝基R盐  乙基紫  分光光度法

Key words:  bismuth  nitros-R salt  ethyl violet  spectrophotometry

摘要:

在pH值为9.80的氨性溶液中,95%乙醇存在下,90℃水浴加热30 min,铋()与亚硝基R盐及乙基紫反应生成紫色缔合物,λ_max=590 nm,表观摩尔吸光系数ε₅₉₀=4.17×10⁸L·mol^-1·cm^-1。铋浓度在0 ng/L~400ng/L范围内遵守比耳定律。据此,建立基于铋-亚硝基R盐-乙基紫反应体系的一个高灵敏测定痕量铋的分光光度方法。该法用于测定水样中的铋,结果较为满意。

Abstract:

In NH₃ solution of pH value=9.80 and the presence of 95% ethyl alcohol, heated at 90℃ for 30 min, bismuth reacts with ethyl violet and nitroso-R salt to form a violet ion-association complex. There is a maximum absorption at 590 nm with an apparent molar absorptivity of 4.17×10⁸ L·mol^-1·cm^-1. Beer's law is obeyed in the range of 0 ng/L to 400 ng/L for Bi(Ⅲ). A higher sensitive spectrophotometry is developed for determining trace bismuth in the system of bismuth nitroso-R salt-ethyl violet. This method has been used to determining bismuth in water samples with satisfactory results.