气质联用法测定环境空气中有机硫化物

采用 SUMMA罐采集空气样品，在预浓缩系统中经3级冷阱捕集后，用气相色谱-质谱联用技术测定环境空气中7种痕量有机硫化物。对试验条件进行优化，使得甲硫醇、乙硫醇、甲硫醚、二硫化碳、噻吩、乙硫醚和二甲二硫醚等7种有机硫化物在21．47μg/m3～336．43μg/m3范围内线性良好。试验表明，7种有机硫化物的方法检出限为0．004μg/m3～0．036μg/m3；标准气体平行测定6次结果的 RSD为2．7％～6．2％，加标回收率为92．2％～97．5％。用该方法测定实际空气样品，并与傅立叶红外光谱法测定的结果进行比对，结果令人满意。

Determination of Organic Sulfur Compounds in Ambient Air by Gas Chromatography Equipped with Mass Spectrometry

Air sample was collected by SUMMA canisters and trapped through three stage cold traps in the pre-concentration system.Gas chromatography equipped with mass spectrometry （GC/MS）made it possible to do qualitative and quantitative analysis for seven kinds of organic sulfur compounds.Experimental conditions were optimized,the calibration curves showed a good linearity from 21.47 μg/m3 to 336.43 μg/m3 for methyl mercap-tan （CH3SH）,ethyl mercaptan （CH3CH2SH）,methyl sulfide （CH3）2S],carbon disulfide （CS2）,thiophene （C4H4S）,1,1′-thiobis-ethane（C4H10S）and dimethyl disulfide （CH3）2S2].Furthermore,experimental results indicated that method detection limits ranged between 0.004 μg/m3 and 0.036 μg/m3 and relative standard de-viation （n=6）of the seven kinds of organic sulfur compounds ranged from 2.7% to 6.2%.Spiked recoveries were between 92.2% and 97.5%.In addition,the study method was successfully applied on monitoring actual air samples.Finally,the experimental results were compared with the fourier transform infrared spectroscopy,satisfac-tory results were obtained.