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

中图分类号：X8       文献标志码：A

文章编号：1008-5548(2015)03-0060-05

DOI:10.13732/j.issn.1008-5548.2015.03.014

收稿日期：2014-10-20， 修回日期：2014-10-31，在线出版时间：2015-06-24。

基金项目：中国科学院战略性先导科技专项，编号：XDB05040501。

第一作者简介：梁苗（1987—），女，博士研究生，研究方向为气溶胶化学。E-mail ：littleweed@163.com。