Development of Dipolar Proton Transfer Reaction Mass Spectrometer for Real-time Monitoring of Volatile Organic Compounds in Ambient Air
10.11895/j.issn.0253-3820.171234
- VernacularTitle:大气挥发性有机物实时在线监测的双极性质子转移反应质谱仪研制
- Author:
Qiang-Ling ZHANG
1
;
Xue ZOU
;
Qu LIANG
;
Ya-Ting ZHANG
;
Ming-Jian YI
;
Hong-Mei WANG
;
Chao-Qun HUANG
;
Cheng-Yin SHEN
;
Yan-Nan CHU
Author Information
1. 中国科学院合肥物质科学研究院
- Keywords:
Dipolar proton transfer reaction mass spectrometry;
Volatile organic compounds;
Real-time;
On-line monitoring
- From:
Chinese Journal of Analytical Chemistry
2018;46(4):471-478
- CountryChina
- Language:Chinese
-
Abstract:
Volatile organic compounds (VOCs) in ambient air can participate in photochemical reactions, which lead to the generation of secondary pollutants such as ozone and aerosol. So real-time and accurate monitoring of atmospheric VOCs plays an important role in the study of the causes of air pollution. On the basis of proton transfer reaction mass spectrometry (PTR-MS) research, a novel dipolar proton transfer reaction mass spectrometer (DP-PTR-MS) for real-time and on-line monitoring atmospheric VOCs was developed. Compared with the conventional PTR-MS with one kind of reagent ion H3O+, DP-PTR-MS had three kinds of reagent ions H3O+, OH-, (CH)2COH+, which could be switched according to the actual detection need. So DP-PTR-MS can improve the qualitative ability and expand the detection range effectively. The reagent ion H3O+can be used for detecting VOCs whose proton affinities are greater than that of H2O. The reagent ion OH-can be used to identify VOCs cooperating with the reagent ion H3O+,and can also be used for detecting some inorganic substances such as CO2. The reagent ion (CH3)2COH+can be used for accurately detecting NH3under interference elimination circumstances. The limit of detection (LOD) and sensitivity of DP-PTR-MS were measured by using six kinds of standard gases. The results showed that the LOD for detecting toluene was 7×10-12(V/V) and the sensitivity for detecting ammonia has reached 126 cps/10-9 (V/V). The ambient air in Hefei city was on-line and real-time monitored for continuous 78 hours with DP-PTR-MS. The results showed that the newly developed DP-PTR-MS could be used for long-term and real-time monitoring atmospheric VOCs with the concentration of 10-12(V/V) level. DP-PTR-MS is an important tool for the study of the causes of atmospheric pollution and the monitoring of trace VOCs emissions.
