【摘要】 研究了2 羟基 4 磺酰氨基苯重氮氨基偶氮苯(HSDAA)的合成及与钴的显色反应.在 Triton X 100表面活性剂存在下,pH=9.0~11.0的Na2B4O7 NaOH缓冲溶液中,试剂 HSDAA与钴(Ⅱ)生成 2∶1 型深红色配合物,配合物的最大吸收峰位于λ=540 nm处,表观摩尔吸光系数为 8.69×104 L·mol-1 ·cm-1,ρ(Co2+)为 0~480μg/L 时符合比耳定律.用拟定方法测定维生素B12中的微量钴,结果满意.更多还原

【Abstract】 The 2-hydroxy-4-sulfamylbenzen-diazoaminoazobenzene（HSDAA） has been synthesized. The color reaction of HSDAA with cobalt was investigated. In the presence of the surface active agent Triton X-100 and in a Na-2B-4O-7-NaOH medium of pH=9.0～11.0, HSDAA with Co（Ⅱ） forms a red complex. The molar absorbability of the complex is ε=8.69×10⁴ L5mol5cm^-1 at the determination wavelength of 540 nm with the molar ratio of Co（Ⅱ） to HSDAA is 1∶2. The Beer′s law is well obeyed in the rang of 0⁴80 μg/L for cobalt at the determination wavelength. This method has been applied to determine trace amounts of cobalt in Vitamin B-（12） with satisfactory results.更多还原