罗丹明S光度法测定痕量二氧化氯

Spectrophotometric determination of trace chlorine dioxide using rhodamine S

在pH为9.5的NH4Cl-NH3缓冲溶液中,罗丹明S在525nm处有一最大吸收峰。当加入二氧化氯后,其吸收峰降低,在525nm波长处的吸光度降低值与二氧化氯质量浓度在0.050～5.0mg/L范围呈良好线性关系,检出限(3倍标准偏差)为0.01mg/LClO2。据此建立了一个灵敏、简便、快速、准确地测定水中痕量二氧化氯含量的方法,用于样品分析,结果令人满意。

In pH 9.5 NH4Cl-NH3 buffer solutions, there is a max absorption peak at 525 nm for rhodamine S. When chlorine dioxide is added, the peak decreased s harply. The results show that the decreased absorbance value at 525 nm is linear to the chlorine dioxide concentration in the range of 0.050-5.0 mg/L. The de tection limit(3 is 0.01 mg/L ClO2. A new spectrophotometric method has been p roposed for the determination of ClO2 in water samples, with advantages includin g high sensitivity, selectivity, simplicity, rapidity and accuracy.