| Title: | Enhanced secondary organic aerosol formation during dust episodes by photochemical reactions in the winter in Wuhan |
| Author(s): | Xu K; Liu Y; Li C; Zhang C; Liu X; Li Q; Xiong M; Zhang Y; Yin S; Ding Y; |
| Address: | "State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China. State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China. Electronic address: liuxingang@bnu.edu.cn. Wuhan Municipality Environmental Monitoring Center, Wuhan 430015, China. College of Environment and Ecology, Chongqing University, Chongqing 400030, China" |
| DOI: | 10.1016/j.jes.2022.04.018 |
| ISSN/ISBN: | 1001-0742 (Print) 1001-0742 (Linking) |
| Abstract: | "To investigate the effect of frequently occurring mineral dust on the formation of secondary organic aerosol (SOA), 106 volatile organic compounds (VOCs), trace gas pollutants and chemical components of PM(2.5) were measured continuously in January 2021 in Wuhan, Central China. The observation period was divided into two stages that included a haze period and a following dust period, based on the ratio of PM(2.5) and PM(10) concentrations. The average ratio of secondary organic carbon (SOC) to elemental carbon (EC) was 1.98 during the dust period, which was higher than that during the haze period (0.69). The contribution of SOA to PM(2.5) also increased from 2.75% to 8.64%. The analysis of the relationships between the SOA and relative humidity (RH) and the odd oxygen (e.g., O(X) = O(3) + NO(2)) levels suggested that photochemical reactions played a more important role in the enhancement of SOA production during the dust period than the aqueous-phase reactions. The heterogeneous photochemical production of OH radicals in the presence of metal oxides during the dust period was believed to be enhanced. Meanwhile, the ratios of trans-2-butene to cis-2-butene and m-/p-xylene to ethylbenzene (X/E) dropped significantly, confirming that stronger photochemical reactions occurred and SOA precursors formed efficiently. These results verified the laboratory findings that metal oxides in mineral dust could catalyse the oxidation of VOCs and induce higher SOA production" |
| Keywords: | *Air Pollutants/analysis Particulate Matter/analysis Dust/analysis China *Volatile Organic Compounds/analysis Aerosols/analysis Water/analysis Oxygen/analysis Minerals Metal oxides Mineral dust Photochemical reactions Soa VOCs; |
| Notes: | "MedlineXu, Kai Liu, Yafei Li, Chenlu Zhang, Chen Liu, Xingang Li, Qijie Xiong, Min Zhang, Yujun Yin, Shijie Ding, Yu eng Netherlands 2023/07/15 J Environ Sci (China). 2023 Nov; 133:70-82. doi: 10.1016/j.jes.2022.04.018. Epub 2022 Apr 19" |
