生活饮用水氯化物硫氰酸汞分光光度测定法

Detection of chloride in drinking water with mercury thiocyanate spectrophotometry

目的：建立生活饮用水氯化物硫氰酸汞分光光度测定方法。方法：氯离子与硫氰酸汞作用，释放出的硫氰酸根离子与铁离子结合生成硫氰酸铁，呈橙红色，呈色强度与氯离子浓度成正比，据此建立了饮用水氯化物硫氰酸汞分光光度测定法。结果：实验条件下，氯化物浓度在0～300mg／L之间，与吸光度存在良好线性关系（r=0．9993）。测定波长460nm。回收率在92％～103％。相对标准偏差2．1％。结论：呈色灵敏、稳定、准确、干扰少，适用于饮用水中氯化物的测定。

Objective ：To establish the method which can be used to determine chloride with mercury thiocyanate spectrophotometry. Methods：The interaction between chloride ion and thiocyanate could release thiocyanate ion which had a chemical reaction with iron ion to generate the salmon pink ferric thiocynate, and there was a positive correlation between the color strength and the concentration of chloride ion. Hereby, we established the method to determine chloride. Results：Under the experimental conditions, the concentration of chloride was 0 - 300 mg/L, and there was excellent linear relationship between the concentration of chloride and the absorbance,r =0. 9993. with detection wavelength at 460 nm. The recovery rate was 92% - 103% and the relative standard deviation was 2. 1%. Conclusion：The method is sensitive, stable, and accurate with little interference, so it is suitable for determining chloride in drinking water.