论文部分内容阅读
报道了新显色剂2－（2－噻唑偶氮）－5－[（N，N－二羧基甲基）氨基]苯磺酸（TADCABS）的合成及其与金属离子的反应，测定了试剂的离解常数．详细讨论了该试剂与Pd2+显色反应的最佳条件，在0.5mol／LHClO4介质中，试剂与钯形成1:1蓝色络合物，其表观稳定常数K稳＝3．96×107.采用双波长法测定，络合物的表观摩尔吸光系数ε（636.4-540.7）=8.05×104，比单波长法测定的灵敏度（ε636.4=5.29×104）提高了52％。反应的灵敏度高，选择性好，可直接用于铂－钯催化剂中微量钯的测定，结果满意．
The synthesis of a new chromogenic reagent 2- (2-thiazolylazo) -5 - [(N, N-dicarboxymethyl) amino] benzenesulfonic acid (TADCABS) and its reaction with metal ions were reported. Dissociation constant. The optimal conditions for the chromogenic reaction of this reagent with Pd2 + were discussed in detail. The reagent formed a 1: 1 blue complex with palladium in 0.5mol / LHClO4 medium. The apparent stability constant K was 3.96 × 107. The apparent molar absorptivity ε (636.4-540.7) of the complex was 8.05 × 104, which was 52% higher than that of the single wavelength method (ε636.4 = 5.29 × 104). The reaction has high sensitivity and good selectivity and can be directly applied to the determination of trace palladium in platinum-palladium catalyst with satisfactory results.