title: Online monitoring of trace chlorinated benzenes in flue gas of municipal solid waste incinerator by windowless VUV lamp single photon ionization TOFMS coupled with automatic enrichment system.
abstract: Chlorinated benzenes are typical precursors and indicators for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) emissions from waste incinerators. Online and real-time monitoring of chlorobenzenes is a challenge due to their low concentration and complex nature of the flue gas. In this work, a continuous online monitoring system was built for detection of trace chlorinated benzenes based on a time-of-flight mass spectrometer (TOFMS). A single photon ionization (SPI) source based on a radiofrequency-excited windowless vacuum ultraviolet (VUV) lamp was developed for the first time to eliminate the signal attenuation resulting from the contamination of magnesium fluoride windows and to avoid the fragment ions. An automatic enrichment system including three parallel Tenax TA adsorption tubes was designed and coupled to the TOFMS to achieve the required ultrahigh sensitivity. The limits of quantitation at 7.65, 5.37 and 6.77pptv were obtained for monochlorobenzene (MCBz), dichlorobenzene (DCBz) and trichlorobenzene (TrCBz), respectively, within a 29-min analytical period. Moreover, this apparatus was applied to continuously online monitor the actual flue gas from a waste incinerator for three months. During this period, the concentrations of MCBz, DCBz and TrCBz detected in the flue gas were in the range of 100-1200, 50-800 and 50-300pptv, respectively. The relative standard deviation (RSD) of the sensitivity for the windowless VUV lamp ion source was 9.71% evaluated by the internal standard benzene over the 3-months flue gas monitoring. These results demonstrated the capability of this method in long-term analysis of the trace chlorinated benzenes in the flue gas.
authors: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China; Graduate University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100039, People's Republic of China.
authors: Wei
authors: W
authors: Liu
authors: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China; Graduate University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100039, People's Republic of China.
authors: Jichun
authors: J
authors: Jiang
authors: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China.
authors: Keyong
authors: K
authors: Hou
authors: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China.
authors: Weiguo
authors: W
authors: Wang
authors: Instrument Science and Electrical Engineering College of Jilin University, 938 West Democracy Street, Changchun 130026, People's Republic of China.
authors: Yachen
authors: Y
authors: Qi
authors: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China; Graduate University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100039, People's Republic of China.
authors: Yan
authors: Y
authors: Wang
authors: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China.
authors: Yuanyuan
authors: Y
authors: Xie
authors: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China.
authors: Lei
authors: L
authors: Hua
authors: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China. Electronic address: hli@dicp.ac.cn.
authors: Haiyang
authors: H
authors: Li
keywords: Automatic enrichment; Chlorinated benzenes; Online monitoring; TOFMS; Windowless VUV lamp