亚硝基-R盐示差分光光度法测定粗钴盐中的钴量

Nitroso-R salt differential spectrophotometric determination of cobalt in crude cobalt salts

示差分光光度法通常用一个浓度略低于待测溶液浓度的标准溶液作为参比,测定待测溶液的吸光度值,作为参比的标准溶液,其准确性会直接影响到标准曲线和待测样品。实验采用10%可见光区透射比标准滤光片为参比,优化亚硝基-R盐示差分光光度法测定高含量钴的显色条件,建立了示差分光光度法测定粗钴盐中钴量的方法。该方法采用参比的示值稳定,不需要与待测试液同步显色,简化了分析流程,提高了分析结果的精密度,在选定条件下,钴量在0.4~0.8mg/100mL范围内工作曲线线性关系好,待测体系中共存组分不干扰钴的测定,样品分析的相对标准偏差(RSD,n=9)为0.19%~0.31%,测定结果与电位滴定法一致。

Differential spectrophotometry usually uses a standard solution with a concentration slightly lower than that of the solution to be tested as a reference to determine the absorbance value of the solution to be tested.As a reference standard solution,its accuracy will directly affect the standard curve and the sample to be tested.In the experiments,the standard filter of 10%visible light transmission is used as reference,and the color development conditions of nitroso-R salt differential spectrophotometry for determination of high content cobalt are optimized.A method for the determination of cobalt in crude cobalt salt by differential spectrophotometry was established.The reference value used in this method is stable,and it does not need to develop color synchronously with the test solution,which simplifies the analysis process and improves the precision of analysis results.Under the selected conditions,the working curve has a good linear relationship in the range of 0.4-0.8 mg/100 mL of cobalt content,and the coexisting components in the system to be tested do not interfere with the determination of cobalt.The relative standard deviation(RSD,n=9)of sample analysis was 0.19%-0.31%.The determination results were consistent with the potentiometric titration method.