钯与2-(4-安替比林偶氮)-5-氨基苯甲酸的显色反应的研究及其应用

Spectrophotometric study on the colour reaction of Palladium with 2-(4-Antipyrinylazo)-5-aminobenzoic acid and its application

摘要: 合成了新试剂2-(4-安替比林偶氮)-5-氨基苯甲酸(AAAB),并研究与钯(Ⅱ)的选择性光度测定方法.在Tween20存在下,试剂与Pd(Ⅱ)形成2:1的红色配合物,λmax=480nm,ε =1.91×104L·mol-1·cm-1,钯在0～1μg/mL范围内符合比尔定律,选择性较好,已用于石钯渣和Pd-活性碳催化剂中微量钯的测定,无需特别分离.方法简便、快速、准确.

Abstract: The synthesis of a new chromogenic reagent 2-(4-antipyrinylazo)-5-aminobenzoic acid(AAAB) is described.A selective spectrophotometry of palladium with AAAB is developed.In the presence of Tween 20,the palladium forms a red complex with AAAB in molar ratio 1:2 and its maximum absorption of is at 480nm.The molar absorptivity is 1.91×104L·mol-1·cm-1.Beer’s law is obeyed over the range of 0～25μg/25mL,and shows good selectivity.The method has been applied to the determination of microamounts of palladium in catalysts or slag containing palladium without special seperation.The proposed method is simple,rapid and accurate.