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报道了一种对钯离子具有高灵敏度和选择性的新试剂２－（２－噻唑偶氮）－５－［（Ｎ，Ｎ－二羧基甲基）氨基］苯甲酸（ＴＡＤＣＡＢ）。在０．５ｍｏｌ／ＬＨＮＯ＿３介质中，ＴＡＤＣＡＢ与Ｐｄ（Ⅱ）形成蓝色配合物，组成为Ｐｄ：ＴＡＤＣＡＢ＝１：２，最大吸收波长６５２ｎｍ。钯浓度在０～１．４μｇ／ｍＬ范围内符合比耳定律。用双波长法测定，表观摩尔吸光系数ε＿（６５２．０～５３３．６）＝８．２×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），可以允许大量金属离子共存。所确立的方法无需掩蔽剂和其它分离手段，即可直接用于Ｐｔ－Ｐｄ催化剂中微量钯的测定，结果满意。
A novel reagent 2- (2-thiazolylazo) -5 - [(N, N-dicarboxymethyl) amino] benzoic acid (TADCAB) with high sensitivity and selectivity to palladium ions has been reported. In 0.5mol / L HNO3 medium, TADCAB forms a blue complex with Pd (II), with the composition of Pd: TADCAB = 1: 2 and the maximum absorption wavelength of 652nm. Beer’s law is in agreement with the palladium concentration in the range of 0-1.4 μg / mL. The apparent molar absorptivity ε_ (652.0 ~ 533.6) = 8.2 × 10 ~ 4L · mol ~ (-1) · cm ~ (-1) measured by dual wavelength method can allow a large amount of metal ions to coexist . The established method without masking agent and other separation means, can be directly used for the determination of palladium in Pt-Pd catalyst with satisfactory results.