离子色谱法测定饮用水中的硫代硫酸盐

Determination of thiosulfate in drinking water by ion chromatography

目的:建立饮用水中硫代硫酸盐的离子色谱测定方法。方法:取饮用水样品2 mL,经0.45μm的水系针式微孔滤膜过滤器过滤后进样测定,采用HS-5A-P3(4.0×250 mm)色谱柱及HS-5AG(4.0×30 mm)保护柱进行色谱分离,以38 mM的KOH浓度淋洗,柱温设置为40℃,泵流速为1.0 mL/min,采用电导检测器检测。结果:在0.22~44.99 mg/L具有良好的线性,相关系数为0.9999,方法检出限为0.025 mg/L,定量下限为0.08 mg/L,加标回收率为94.7%~111.0%,相对标准偏差(RSD)为0.66%~1.41%。某桶装饮用水检出浓度为29.88 mg/L。结论:本方法预处理简便,操作快速、便捷,灵敏度高,经济成本较低,准确度和精密度均较高,可用于饮用水中硫代硫酸盐的检测。

Objective:To establish a method for the determination of thiosulfate in drinking water by ion chromatography.Meth-ods:Two mL drinking water sample was taken,filtered by 0.45μm water needle microporous membrane filter before sampling determination.The separation was performed on a HS-5A-P3(4.0×250 mm)column and a HS-5AG(4.0×30 mm)col-umn.38 mmol/L KOH was used as the eluent.The column temperature was set at 40℃,and the pump flow rate was 1.0 mL/min.The conductivity detector was used for detection.Results:In the range of 0.22~44.99 mg/L,the linear correlation coeffi-cient was 0.9999,and the detection limit of the method was 0.025 mg/L,the limit of quantification was 0.08 mg/L.The recov-ery rates were 94.7%~111.0%,with the relative standard deviation(RSD)of 0.66%~1.41%.The detected concentration of a barreled drinking water is 29.88 mg/L.Conclusion:This method is simple,quick,convenient and sensitive,which has low economic cost,high accuracy and precision.It is applicable to the determination of thiosulfate in drinking water.