加速溶剂萃取/GC-ECD分析土壤中多氯联苯的研究

Accelerated Solvent Extraction and GC/ECD for Measuring Polychlorinated Biphenyls in Soil

为研究加速溶剂萃取土壤中的多氯联苯的方法，以土壤中8种多氯联苯为标样，进行了加速溶剂提取实验，并用佛罗里硅土柱净化,再用GC-ECD气相色谱仪测定。实验优化了萃取条件，在20 g土壤样中添加50 ng多氯联苯混标，在实验温度100℃,萃取压力为10.3 MPa，萃取时间为20 min条件下用35 mL丙酮/正己烷混合液提取，并用GCECD测得多氯联苯回收率为95.63%～100.2%；相对标准偏差为0.95%～9.58%；方法检出限为0.089～0.882 ng/g。为进行比较,同时进行了超声波辅助提取和索式提取实验。结果表明：加速溶剂提取时间短,有机溶剂用量少,并且提取回收率高。

Accelerated solvent extraction （ASE） was developed to extract 8 kinds of polychlorinated biphenyls （PCBs） in soil and using gas chromatography equipped with electron captured detector （ECD） was to analyze target compounds. Some extracting factors were studied. Under the optimal extraction conditions, comparing ASE with soxhlet extraction （SE） and ultrasonic-wave extraction （UE）, the results showed that ASE method is simple, solvent-saving and time-saving. The accuracy of the proposed method was tested by recovery measurements on spiked samples, recoveries results were 95.63-100. 2 %. The relative standard deviation was 0.95%-9. 58%, and the detection limits of this method were 0.089-0.882ng/g （n=5）.