摘要：利用自主研发的高灵敏度真空紫外光电离飞行时间质谱仪(VUV-TOFMS),对一氯苯、1,2-二氯苯和1,2,4-三氯苯3种氯苯类二恶英前体物进行在线检测,对聚氯乙烯燃烧产生的模拟烟气、一氯苯的实时浓度进行在线监测,并对燃烧产生的二恶英浓度进行初步量化分析。结果表明:VUV-TOFMS间接实现了对垃圾焚烧二恶英产物的检测;得到了较准确的母体离子信号峰,信号强度与实际浓度的线性关系良好,一氯苯、1,2-二氯苯和1,2,4-三氯苯的检出限(体积分数)分别达到4.7×10^-9、8.7×10^-9、11.9×10^-9。

关键词：二恶英前体物；真空紫外光电离飞行时间质谱仪；在线检测

Abstract： A high-sensitive vacuum ultraviolet time-of-flight mass spectrometer （VUV-TOFMS） researched and developed independently was applied to the on-line detection of three chlorobenzenes used as dioxins precursors including monochlorobenzene, 1, 2-dichlorobenzene, and 1,2,4 -trichlorobenzene. The simulated flue gas generated by the combustion of PVC and the real-time concentration of monochlorobenzene was on-line monitored. The dioxins concentration generated by combustion was quantitatively analyzed. The results show that the detection of dioxins products from waste incineration is indirectly realized by VUV -TOFMS. Accurate and distinct parent molecular ions are observed. The signal intensity of the molecular ion shows a good linear relation with real concentration of the standard gas. The detection limits for monochlorobenzene, 1, 2-dichlorobenzene and 1,2,4 -trichlorobenzene are respectively 4.7×10^-9, 8.7 ×10^-9 and 11.9×10^-9. 

Keywords: dioxins precursor; vacuum ultraviolet time-of-flight mass spectrometer; on-line monitoring