土壤中苯系物的顶空气相色谱测定方法研究  

Measurement and determination of BTEX in the soil by the headspace-gas chromatography

作　　者：刘佳[1,2] 宋子岭[1] 丛鑫[1] 谷庆宝[2] 

机构地区：[1]辽宁工程技术大学资源与环境工程学院,辽宁阜新123000 [2]中国环境科学研究院土壤污染与控制研究室,北京100012

出　　处：《安全与环境学报》2011年第6期98-101,共4页Journal of Safety and Environment

基　　金：环保公益性行业科研专项经费项目(200809095)

摘　　要：目前土壤中苯系物还没有标准的测定方法。采用顶空气相色谱法建立了一种测定污染土壤中苯系物(苯、甲苯、乙苯、对(间)二甲苯、邻二甲苯、异丙苯)的方法。着重讨论了顶空平衡温度、平衡时间及基质修正液的加入量等因素对苯系物测定结果的影响,并优化了试验参数。结果表明,顶空平衡温度为70℃,平衡时间为20 min,基质修正液的加入量为3 mL是最优试验条件。在此试验条件下,苯系物各组分能够完全分离,线性较好,决定系数在0.990 5～0.996 1,方法的检出限在2.0～6.4μg/kg,回收率为95.5%～98.6%,相对标准偏差小于11.1%。测定结果显示,该方法有很好的相关性,简单、准确、快捷,适用于土壤中苯系物的测定。The present paper is engaged in a investigation of measurement and determination of BTEX in the soil by the headspace-gas chromatography efficiency and reliability of the method for the extraction of BTEX such as benzene, toluene, ethylbenzene, p（m）-xylene, o-xylene and the isopropylbenzene from the headspace of soil samples. As a matter of fact, BTEX is widely used in the industrial companies as chemical materials and, due to its overuse, the soil has become contaminated through spillage of industrial solvents, leakage of petrol from the storage facilities and deposition from contaminated air. However, there has not been established any standard method for its monitoring in the soil. It is for this purpose that we have proposed a headspace gas chromatography method for determining the volatile BTEX in the contaminated soil with a detailed discussion on how to use our method properly in this paper. As is suggested in our method, monitoring of the extracted compounds and further quantitative analysis of the samples selected can be done just by the capillary gas chromatograph equipped with a flame-ionization detector （GC-FID）. We have also studied the effects of some factors such as headspace equilibration temperature, equilibration time and the modifying solutions to the monitoring results, with the extraction parameters being optimized through the experimental data. The optimal extraction conditions as the results of our study have been worked out for 50 minutes from the headspace of polluted soil at a temperature of 60 ℃ and the modifying solution volumes was 3 mL. Under these optimum experimental conditions, BTEX were able to be separated from each other completely, with the calibration graphs being linear in the range 5 to 400 μg/kg. The correlation coefficients of the linear calibration graphs were found to be 0.990 5-0.996 1. Excellent as the linearity may be, there remain the detection limits in a range of 2.0-6.4 μg/kg, which can be used to demonstrate that our measurement and determination met

关 键 词：环境化学 污染土壤 苯系物 顶空气相色谱 

分 类 号：X53[环境科学与工程—环境工程]