水中硬度的流动注射化学发光分析法测定

Flow injection chemiluminescence method for determination of hardness of water

目的：建立了流动注射化学发光法测定水中硬度的新方法。方法：实验发现在碱性介质中,高锰酸钾氧化酸性铬蓝K可产生较强的化学发光,而且Ca,Mg离子对该体系的化学发光强度有明显的增强作用;结合流动注射技术,建立了流动注射-化学发光增强法测定水中硬度的方法。结果：该法的化学发光增强值（ΔI）与水中Ca,Mg离子的总浓度在3.0×10-9～7.5×10-7mol/L和4.0×10-6～1.0×10-4mol/L范围内呈良好的线性关系,其线性回归方程分别为△I=9.615？（X）＋66.382（线性相关系数r=0.9575）和△I=171.74？（X）＋211.73（线性相关系数r=0.9911）。检出限为2.7×10-9mol/L。对浓度为10-5mol/L的标准样品进行11次测定RSD为4.8%。结论：本文实验证明在氢氧化钠介质中,高锰酸钾氧化酸性铬蓝K结合流动注射技术检测水中硬度方法的是可行的。方法简单、准确、便于自动分析,为进行环境水硬度的自动检测提供了可能。

Objective：It was found that acid chrome blue K could generate a good light signal when it was mixed with potassium permanganate in potassium hydroxide solution.Methods：A novel flow injection procedure was developed for the determination of the total hardness in water based on the enhancement of the chemiluminescence from potassium permanganate-acid chrome blue K-sodium hydroxide solution system by calcium and magnesium.Results：The linear range for determination of the total content of calcium and magnesium was 3.0×10-9～7.5×10-7 mol/L,and 4.0×10-6～1.0×10-4 mol/L,respectively.The method was simple with high sensitivity and selectivity,and with a detection limit of 2.7×10-9 mol/L.Conclusion：This method is applied to determine the hardness of water with satisfactory results.