巯基葡聚糖凝胶分离微乳液介质邻氯苯基荧光酮光度法测定钴(Ⅱ)

Spectrophotometric Determination of Cobalt(Ⅱ) with o-Chlorophenylfluorone in Microemulsion after Sulfhydryl Dextrane Gel for Preconcentration and Separation

研究了在微乳液介质中 ,pH =10 .0时 ,钴与邻氯苯基荧光酮 (o CPF)显色生成稳定的 1:2配合物 ,在 6 5 0nm处摩尔吸光系数为 1.31× 10 5L·mol-1·cm-1,钴含量在 0～ 1.0 μg/mL范围内符合比耳定律 ,用所拟方法以巯基葡聚糖凝胶分离富集 ,可测定环境样品中的微量钴 ,结果令人满意。

In this paper,the color reaction of cobalt with o-chlorophenylfluorone (o CPF) in microemulsion has been studied.Cobalt (Ⅱ) reacts with o CPF to form a stable 1:2 complex at pH 10.0.Its apparent molar absorptivity is 1.31×10 5? L·mol -1 ·cm -1 at 650 nm.Beer's law is obeyed in the range of 0～1.0?μg/mL for cobalt (Ⅱ).The coexistent metal ions can be separated and cobalt can be enriched by sulfhydryl dextrane gel (SDG),greatly improving the selectivity and sensibility of system.The method is used to determine cobalt in vitamin B 12 samples with satisfactory results.