Pd(Ⅱ)—二溴对甲偶氮羧—吐温-80用于微量钯的分光光度测定

Spectrophotometric Determination of Trace Pd in Pd(Ⅱ)—Dibromo-p-Methylcarboxylazo—Tween-80 System

当吐温 - 80存在时 ,Pd(Ⅱ )与二溴对甲偶氮羧的显色反应呈现了很高的灵敏度和选择性。其摩尔吸光系数ε62 3=4 6× 1 0 4 L·mol- 1 ·cm- 1 ,Pd含量在 0 1～ 0 5μg·ml- 1 符合比耳定律。这种水相中直接测定微量钯的分光光度分析法已用于钯催化剂和二次阳极泥中微量钯的测定。

The condition of colour reaction of Pd(Ⅱ) with dibromo-p-methylcarboxylazo in the presence of tween-80 are studied.Palladium is directly determined in aqueous solution.A highly sensitive spectrophotometric procedure is investigated for the determination of trace palladium.The molar absorptivity is 4 6×10 4 L·mol -1 ·cm -1 at 623nm.Beer's law is obeyed in the range from 0 1 to 1 5 μg·ml -1 for Pd(Ⅱ) contents.This method has been applied to the determination of trace palladium in the catalyst with satisfactory results.