室内空气中苯系物的溶剂解吸气相色谱法测定

Determination of benzene series chemical in room air by solvent desorption gaschromatography

目的确认室内空气中苯、甲苯、二甲苯的溶剂解吸气相色谱测定方法,并应用于本实验室实际样品的检测。方法采用活性碳管吸附室内空气中苯、甲苯和二甲苯,经二硫化碳解吸,DM Wax色谱柱作为分离柱,FID检测器检测苯、甲苯和二甲苯浓度。结果苯、甲苯、邻二甲苯、间二甲苯、对二甲苯在DM Wax色谱柱上分离良好,标准曲线相关系数可达0.999 9以上;线性范围(0.1~20)μg/m L;样品平均解吸效率在95.2%~103.8%,相对标准偏差为0.4%~2.5%,最低检出限0.003 1~0.0 05 6 mg/m^3;质控样品浓度均在定值范围之内。结论该溶剂解吸气相色谱法分离效果好,操作简单,准确性好,精密度高,适用于评价室内空气苯、甲苯和二甲苯污染物浓度。

Objective To determinate benzene, toluene and xylene in the indoor air by solvent desorption gas chromatography, and to apply to the detection of the actual samples in the laboratory. Methods By using activated carbon tube adsorption of benzene in the room air and carbon disulfide desorption, with DM wax chromatographic column as the separation column, FID detector was used to detect the concentration of benzene, toluene, and xylene. Results Benzene, toluene, o- xylene, m-xylene and p-xylene were well separated in DM wax chromatographic column, with the correlation coefficient of standard curve of over 0. 9999. The linear range was O. 1 - 20 μg/mL. The sample average desorption efficiency was between 95.2% and 103.8% , with the relative standard deviation of 0.4 % - 2. 5%. The minimum detection limit was 0. 0031 to 0. 005 6 mg/m3. The concentrations of quality control samples were all within the setting range. Conclusion Solvent desorption gas chromatography has advantages of separation effect, simple operation, good accuracy, high precision, and suitable for evaluating the concentration of indoor air pollutants sllch as benzene, toluene, and xylene.