加速溶剂萃取-固相柱净化-气相色谱法测定土壤中18种多氯联苯

Determination of polychlorinated biphenyls in soil by gas chromatography combined with accelerated solvent extraction and solid phasecolumn cleanup

建立加速溶剂萃取(ASE)、固相柱净化结合双电子捕获检测器(ECD)气相色谱法同时测定土壤中18种多氯联苯(PCBs)的方法。比较了不同的萃取方式、萃取溶剂,以及不同的净化方式等对提取净化效率的影响。18种多氯联苯在2.00~500μg·L^(-1)质量浓度范围内线性良好,线性相关系数为0.9992~0.9999,方法检出限为0.02~0.04μg·kg^(-1),空白石英砂加标回收率为75.2%~108%,相对标准偏差为0.9%~5.1%。通过对变电站实际土壤样品检测,能够准确定量污染土壤中多氯联苯水平,变电站实际土壤样品中18种多氯联苯的加标回收率为70.6%~102%,相对标准偏差为2.3%~8.7%。该方法简单、快速,回收率和检出限均能满足质量控制要求,适用于污染源场地内土壤风险的筛查和管控。

A method for the determination of 18 Polychlorinated Biphenyls(PCBs)in Soil by using accelerated solvent extraction(ASE)and Silicagel column cleanup with Gas Chromatography-Dual Electron Capture Detection,and the effects of different extraction methods,Extraction solvent and cleanup methods on standard recovery were compared.The linearity of the method ranged from 2.00μg·L^(-1) to 500μg·L^(-1) for 18 PCBs,with correlation coefficients ranging from 0.9992 to 0.9999.The detection limits for 18 PCBs were 0.02~0.04μg·kg^(-1).The standard recovery of blank quartz sand is 75.2%~108%,the relative standard deviation is 0.9%~5.1%.Through the detection of actual soil samples in substations,the level of PCBs in contaminated soil can be accurately quantified,The standard recovery of soil samples in substations is 70.6%~102%,the relative standard deviation is 2.3%~8.7%.The method is simple and rapid,and the recovery rate and detection limit can meet the quality control.It is suitable for screening and control of soil risk in pollution source sites.