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

在 p H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 ,λmax=5 90 nm,表观摩尔吸光系数 ε5 90 =4.17× 10 8L.mol- 1 .cm- 1。铋浓度在 0 ng/ L～ 40 0ng/ 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 。

In NH 3 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 17×10 8 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.