【摘要】 通过对钴(Ⅱ)与紫脲酸铵显色反应的研究,建立了一种测定微量钴的新方法.pH为8～9时钴(Ⅱ)与紫脲酸铵反应生成1:3络合物,其Aλmax为458 nm,ε为2.65×104L/(cm·mol),钴浓度在0.0～2.0 mg/L范围内服从比尔定律.通过对维生素B12中钴的测定,相对标准偏差为1.43％～2.17％,加标回收率为97％～112.5％.更多还原

【Abstract】 A new method for determination of trace cobalt was developed through the study on the color reaction for murexide with cobalt. The results showed that combalt formed stable complex with murexide at pH 8-9.The molar ration of cobalt to murexide was found to be 1:3. Its apparent molar absorptirity was 2.65 × 104 L/(cm·mol) at 458 nm.Beer’s law was obeyed in the range of 0.0-2.0 mg/L for cobalt.The method was used to determine cobalt in VB12. The recovery was 97% -112.5% with RSD of less than 2.17%.更多还原