大体积进样离子色谱法测定环境水样中高氯酸根

Determination of Perchlorate in Nature Water by Ion Chromatography with Large Volume Injection

采用大体积500μL进样离子色谱法，电导榆测测定了几种水体中高氯酸盐的含量。分析柱为容量高、亲水性强的以脂肪族碳骨架为基质的阴离子交换柱lonPac AS20。淋洗液在线发生器自动产生35mmol／L，KOH淋洗液，0．25mL／min等浓度淋洗。这种新型的以脂肪族碳骨架为基质的阴离子交换柱的采用．极大的削弱了该色谱柱对对氯苯磺酸的保留，完全消除了现行美国EPA高氯酸盐分析方法中高氯酸根与对氯苯磺酸共淋洗的问题。方法对高氯酸根的检出限（S／N=3）为0．5μg／L，高氯酸根浓度在1-1000μg／L范围内具有良好的线性（r=0．9991）。将本方法应用于自来水、河水和雪水样品中高氯酸盐的检测。实际样品的加标回收率在87％-114％之间；1μg/L高氯酸根连续进样9次，色谱峰面积相对标准偏差（RSD）为6．9％。

The method for trace perchlorate analysis in environmental water was set up with large volume （500 μL ） injection ion chromatography and conductivity detection. Perchlorate was separated with high capacity and hydroxide selective column （ IonPac AS20） using 35 mmol/L KOH eluent at the flow rate of 0.25 mL/min. The eluent was generated on-line from EGC. The column has unique substrate coating of aliphatic backbone which makes the retention time of 4-chlorobenzene sulphonate ahead of perchlorate thus eliminating its interference with perchlorate. The detection limit of perchlorate was as low as 0.5 μ g/L. A linear calibra- tion was obtained over the range of 1 to 1000 μg/L with a correlation coeffient of 0. 9991. The method was applied to the detection of perchlorate in Beijing＇s tap water and snow water. The recoveries of spiked standard were in the range of 87% - 114%. RSD of the peak area for the nine successive injections of 1μg/L perchlorate solution was 6.9%.