新显色剂BTASTP在分析中的应用 Ⅱ 分光光度法测定钯

Analytical Application of a New Thiazolylazo Reagent BTASTP Ⅱ. Spectrophotometric Determination of Palladium

本文报道了一种对Pd(Ⅱ)有高灵敏度和选择性的新试剂2-(2-苯并噻唑偶氮)-4-甲基-5-磺甲氨基苯膦酸(BTASTP)。实验结果表明,在较高酸度的硝酸介质中,钯与BTASTP形成组成为1∶1的稳定的蓝色配合物,表观摩尔吸光系数为6.24×10~4L·mol^(-1)·cm^(-1),钯含量在0～50μg/25mL范围内服从比尔定律,可以允许大量的共存离子包括贵金属离子存在。所拟方法用于铜镍合金、贵金属氯化渣、贵金属高锍中钯的测定,获得满意结果。

In this paper, a new thiazolylazo reagent 2-（2-benzothiazo lylazo）-5-sulfomethylamino-4-tolylphosphonic acid （BTASTP） was reported as a high sensitive and extra selective chromogenic reagent for palladium. The results show that BTASTP and palladium form a stable blue chelate in a strong nitric acid medium with a molar ratio of 1 to 1, the apparent molar absorptivity of the chelate is 6.24×104L·mol-1·cm-1. Berr’s law is obeyed in the range of 050μg Pd/25mL. Relatively large amounts of coexisting elemets including noble metals can be tolerated. The proposed method has been applied to the determination of palladium in Cu-Ni alloys, chloride residue of noble metals and sulfonium compound of noble metals with satisfactory results.