用ASE提取和GPC净化气相色谱法快速测定土壤中痕量有机氯代化合物

Determination of trace persistent organochlorine compounds in soil by gas chromatography with accelerated solvent extraction and gel permeation chromatography cleanup

本研究介绍了土壤中20种不同持久性有机污染物的分析方法，包括6种多氯联苯（PCB15，PCB28，PCB52，PCB101，PCB118，PCB138）和14种有机氯农药（α-666，β-666，γ-666，δ-666，P，P’-DDE，P，P’-DDD，O，P＇-DDT,P，P＇-DDT,Heptachlor,Aldrin，trans—Chlordane，cis．Chlordane，Dieldrin，Endrin）．土样通过加速溶剂提取，经装有Biobeads S-X3柱填料的自动凝胶渗透色谱和氟罗里硅土及石墨碳黑填料的固相萃取柱净化，最后用带电子捕获检测器的气相色谱分析测定．实验结果表明该法获得很好的回收率70．7％-98．0％，相对标准偏差为2．19％-10．8％，检出限为0．33ng．g^-0．94ng·g^-1．与传统的提取方法相比，加速溶剂提取具有操作简便，省时省溶剂，减少有机溶剂对环境污染的特点．优化后的方法可测定多种土壤样品中有机氯代化合物，并且能够在日常分析中得到应用．

A new analytical method was presented for the determination of 20 different persistent organochlorine compounds, including 6 polychlofinated biphenyls （（PCB15, PCB28, PCB52, PCB101, PCB 118, PCB138）） and 14 organochlorine pesticides （α-666, β-666, γ-666, δ-666, P,P＇-DDE, P,P＇-DDD, O,P＇-DDT, P,P＇-DDT, Heptachlor, Aldrin, trans-Chlordane, cis-Chlordane, Dieldrin, Endrin） in soil samples. The optimum extraction and cleanup procedures were examined using acceleraterated solvent extraction （ASE）, automated gel permeation chromatography （GPC） on Biobeads S-X3 and solid phase extraction （SPE） on Florisil and Carb. Detection could be achieved by gas chromatography with electron-capture detection （CK2-ECD）. The results showed that with this method satisfactory recoveries 70.7%-98.0%, relative standard deviation （RSD） 2.19%-10.8%and detection limits 0.33 ng·g^-1-0.94 ng·g^-1 could be obtained. Compared to other methods, ASE was simple and convenient to conduct, rapid, and used less solvent, thereby limiting environmental contamination. The optimized method was capable of handling various soil samples, and it was confirmed that the method could be used in routine analysis .