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有机硫是环境空气中重要的恶臭物质,它的挥发性、不稳定性等理化性质使得低浓度有机硫的采样检测存在很大难度,其检测方法还不完善.为此,建立一种低温捕集浓缩-热解吸-气相色谱检测技术,用于低浓度有机硫恶臭物质的检测分析.以甲硫醚和乙硫醇为代表,研究采样管的吸附-热解吸过程,优化采样条件.结果表明:在液氮为制冷剂形成的低温环境下,有机硫恶臭物质可有效富集在活性炭吸附采样管内,低温浓缩饱和吸附容量为0.1～0.3 g·g-1;在20 mL·min-1氮气吹扫下最佳热解吸温度230℃,解吸时间200 min.采样浓度为50 μg·L-1～16 mg· L-1时,分析方法对甲硫醚和乙硫醇的平均相对标准偏差小于5％,精密度检测限达到μg·L-1级.“,”Volatile organic sulfur compounds are the major chemicals associated with odor pollution.There are challenges in the sampling and determination of the trace level odor organic sulfur compounds due to their volatility and mutability.Currently,the detection method for volatile organic sulfur compounds in the atmosphere is not perfect.In this study,detection technology was established to measure the trace concentration of volatile organic sulfur compounds in the atmosphere,and included cryogenic trap adsorption,thermal desorption,and gas chromatography.Dimethyl sulfide and ethyl mercaptan were chosen as representatives.A series of adsorption and thermal desorption experiments were conducted to determine the effects of important operating parameters.Ethyl mercaptan and dimethyl sulfide were adsorbed effectively by activated carbon in the sampling tube,which was placed in a cryogenic environment provided by liquid nitrogen (-130 ℃).The cryogenic saturated adsorption capacity of activated carbon was 0.1 to 0.3 g · g-1,and the optimum desorption temperature was 230 ℃ at 200 min,with a nitrogen flow rate of 20 mL · min-1.The relative standard deviations is less than 5％,when the concentration ranged from 50 μg · L-1 to 16 mg · L-1.The method detection limits wereμg · L-1 concentration level.