离子色谱法测定饮用水中高氯酸盐残留量

Determination of perchlorate residue in drinking water by ion chromatography

目的建立离子色谱法测定饮用水中高氯酸盐的方法,了解福州市城区市政供水和周边县地下水高氯酸盐残留状况。方法选用Ionpac AS20阴离子分析柱,在线产生30 mmol/L KOH淋洗液,流速1.00ml/min,柱温30℃,抑制器电流75mA,进样体积500μl,电导检测器检测。应用该方法检测福州市城区市政供水和周边县的井水共52份,并依据世界卫生组织(WHO)2017年发布的饮用水高氯酸盐标准限值进行评价。结果高氯酸盐在0.002~0.15mg/L范围内线性良好,精密度高(RSD%<3.0)相关系数>0.9995;回收率95.60%~108.00%;方法最低检出限0.54μg/L,定量限1.78μg/L。52份水样检出高氯酸盐残留15份,检出率28.85%,均符合WHO的要求。结论该方法简单、快速、灵敏,可适用于饮用水中高氯酸盐检测;福州市城区市政供水水质良好,周边县地下水存在高氯酸盐污染风险,应加强监测。

Objective To establish a method for the determination of perchlorate in drinking water by ion chromatography,and to understand the status of perchlorate residue in municipal water in urban area and in underground water in surrounding counties.Methods 500μl of water sample was loaded into IonPac AS20 anion column at 30℃,30 mmol/L KOH was used as isocratic eluent with the flow rate of 1.00 mL/min.The electric current was set at 75 mA and the conductance detector was used to detect perchlorate.A total of 52 water samples were detected and assessed according to the standard limits of perchlorate for drinking water issued by the world health organization(WHO)in 2017.Results This method had good linear relation in perchlorate concentration range of 0.002-0.15 mg/L with high analytic precision(RSD%<3.0).The correlation coefficient was higher than 0.9995.The recovery rate was within the range of 95.60%-108.00%.The lower detection limit was 0.54μg/L and the quantitative limit was 1.78μg/L.15 samples were found of having high perchlorate residues with the detection rate of 28.85%.The levels of perchlorate residues in drinking water met the requirements of the standard limits by WHO.Conclusions This method is simple,rapid,sensitive and can be used for the detection of perchlorate in drinking water.The municipal water supply in Fuzhou city is safe,while the underground water in surrounding counties has the risk of perchlorate pollution.