热分离进样-低热容气相色谱-质谱法测定空气中苯系物
马小杰,李明芳,李明明
山东省临沂生态环境监测中心,山东临沂 276000
Determination of benzene series in air by low heat capacity gas chromatography-mass spectrometry with thermal separation injection
马小杰,李明芳,李明明
Shandong Linyi Ecological Environment Monitoring Center, Linyi 276000, China
摘要:建立了一种热分离进样-低热容气相色谱-质谱法测定空气中苯系物的方法。使用微吸附采样器,安装膜厚为20 μm的PLOT-Q捕集短柱采集气体样品,采样流量为100 mL/min,在热分离进样杆中完成目标化合物的脱附后进入DB-5 LTM色谱柱进行分离,使用气相色谱-质谱法定性、定量分析。结果表明,7种苯系物的质量在34.8~1419 ng范围内与各自的色谱峰面积线性关系良好,相关系数均大于0.992,以200 mL采样体积计算,空气中检出限为0.006~0.012 mg/m3。方法的相对标准偏差为2.4%~8.7%(n=6),平均回收率为89%~103%。该方法无需样品前处理,重复性好,检出限满足相关环境质量和排放标准要求,适合空气中苯系物的快速测定。
Abstract:A method for the determination of benzene series(BTEX) in air by gas chromatography-mass spectrometry (GC-MS)with thermal separation injector was established. A PLOT-Q short column with a membrane thickness of 20 μm was used to collect the samples with a micro adsorption sampler. The target compounds were desorbed in the thermal separation injection rod and separated in a DB-5 LTM chromatographic column. The quantitative analysis was performed by gas chromatography-mass spectrometry. The results showed that the peak area of seven benzenes had good linear relationship with their chromatographic peak area in the range of 34.8-1419 ng, the correlation coefficients were more than 0.992, and the detection limits were in the range of 0.006-0.012 mg/m3 with the sampling volume was 200 mL. The relative standard deviations were 2.4%-8.7% (n=6), and the recovery rates ranged from 89%-103%. The method has no sample pretreatment, good repeatability and low detection limit. It is suitable for rapid determination of BTEX in air.
关键词:热分离进样杆;气相色谱-质谱法;苯系物
Keywords:thermal separation injector; gas chromatography-mass spectrometry; benzene series
本文引用格式:
马小杰,李明芳,李明明.热分离进样-低热容气相色谱-质谱法测定空气中苯系物[J].化学分析计量,2021,30(7):42.
Ma Xiaojie,Li Mingfang,Li Mingming. Determination of benzene series in air by low heat capacity gas chromatography-mass spectrometry with thermal separation injection[J]. Chemical Analysis and Meterage,2021,30(7):42.
相似文章: