壳聚糖富集分离镉黑T褪色光度法测定痕量锰的研究

Spectrophotometric determination of trace manganese by chitosan separation-fading reaction of eriochrome black T

常温下,在pH=8的硼酸-氯化钾-氢氧化钠介质中,Mn(Ⅶ)能显著的氧化铬黑T褪色,且褪色程度随Mn(Ⅶ)量变化呈线性关系,据此建立了测定微量锰的新方法。实验测定波长为620 nm,表观摩尔吸光系数为1.31×105L/(mol.cm),该方法的线性测定范围为0～10μg/25 mL,相关系数为r=0.999 7。方法简便、快速、准确,精密度和灵敏度高;采用壳聚糖富集分离和EDTA掩蔽,方法在用于测定钢样中锰的含量时,结果非常满意。

A novel method for the determination of manganese was established.It was based on the fading reaction of eriochrome black T oxidized by Mn（VII） in the medium of pH=8.The colour decreasing was directly proportional to the amount of manganese.The maximum absorption was at 620 nm.The apparent molar absorptivity was 1.31×105 L/（mol·cm）.The linear range of determination was 0~10 μg/25 mL.Correlation coefficient was 0.999 7.The method was simple,fast,accurate and high sensitivity.The chitosan separation and EDTA masking has been applied to the determination of trace manganese in aluminum and steel sample with satisfied results.