1
|
Zou Y, Yan XL, Flores RM, Zhang LY, Yang SP, Fan LY, Deng T, Deng XJ, Ye DQ. Source apportionment and ozone formation mechanism of VOCs considering photochemical loss in Guangzhou, China. Sci Total Environ 2023; 903:166191. [PMID: 37567293 DOI: 10.1016/j.scitotenv.2023.166191] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 08/07/2023] [Accepted: 08/08/2023] [Indexed: 08/13/2023]
Abstract
Understanding the sources and impact of volatile organic compounds (VOCs) on ozone formation is challenging when the traditional method does not account for their photochemical loss. In this study, online monitoring of 56 VOCs was carried out in summer and autumn during high ozone pollution episodes. The photochemical age method was used to evaluate the atmospheric chemical loss of VOCs and to analyze the effects on characteristics, sources, and ozone formation of VOC components. The initial concentrations during daytime were 5.12 ppbv and 4.49 ppbv higher than the observed concentrations in the summer and autumn, respectively. The positive matrix factorization (PMF) model identified 5 major emission sources. However, the omission of the chemical loss of VOCs led to underestimating the contributions of sources associated with highly reactive VOC components, such as those produced by biogenic emissions and solvent usage. Conversely it resulted in overestimating the contributions from VOC components with lower chemical activity such as liquefied petroleum gas (LPG) usage, vehicle emissions, and gasoline evaporation. Furthermore, the estimation of ozone formation may be underestimated when the atmospheric photochemical loss is not taken into account. The ozone formation potential (OFP) method and propylene-equivalent concentration method both underestimated ozone formation by 53.24 ppbv and 47.25 ppbc, respectively, in the summer, and by 40.34 ppbv and 26.37 ppbc, respectively, in the autumn. The determination of the ozone formation regime based on VOC chemical loss was more acceptable. In the summer, the ozone formation regime changed from the VOC-limited regime to the VOC-NOx transition regime, while in the autumn, the ozone formation regime changed from the strong VOC-limited regime to the weak VOC-limited regime. To obtain more thorough and precise conclusions, further monitoring and analysis studies will be conducted in the near future on a wider variety of VOC species such as oxygenated VOCs (OVOCs).
Collapse
Affiliation(s)
- Y Zou
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Institute of Tropical and Marine Meteorology, China Meteorological Administration (CMA), Guangzhou 510640, China
| | - X L Yan
- State Key Laboratory of Severe Weather & Institute of Tibetan Plateau Meteorology, Chinese Academy of Meteorological Sciences, Beijing, China
| | - R M Flores
- Marmara University, Department of Environmental Engineering, Istanbul, Turkey
| | - L Y Zhang
- Institute of Tropical and Marine Meteorology, China Meteorological Administration (CMA), Guangzhou 510640, China
| | - S P Yang
- Institute of Tropical and Marine Meteorology, China Meteorological Administration (CMA), Guangzhou 510640, China
| | - L Y Fan
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - T Deng
- Institute of Tropical and Marine Meteorology, China Meteorological Administration (CMA), Guangzhou 510640, China
| | - X J Deng
- Institute of Tropical and Marine Meteorology, China Meteorological Administration (CMA), Guangzhou 510640, China
| | - D Q Ye
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
| |
Collapse
|
2
|
Huang XF, Zhang B, Xia SY, Han Y, Wang C, Yu GH, Feng N. Sources of oxygenated volatile organic compounds (OVOCs) in urban atmospheres in North and South China. Environ Pollut 2020; 261:114152. [PMID: 32066058 DOI: 10.1016/j.envpol.2020.114152] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 02/07/2020] [Accepted: 02/07/2020] [Indexed: 05/22/2023]
Abstract
Oxygenated volatile organic compounds (OVOCs) are critical precursors of atmospheric ozone (O3) and secondary organic aerosols (SOA). Although China is experiencing increasing O3 pollution from north to south, understanding the major sources of OVOCs in this region is still limited due to their active photochemical behaviors. In this study, five critical OVOCs at a northern urban site (Beijing) and a southern urban site (Shenzhen) were monitored in summer using proton transfer reaction-mass spectrometry (PTR-MS). The mean total concentration of VOCs measured in Beijing (39.4 ppb) was much higher than that measured in Shenzhen (16.7 ppb), with methanol and formaldehyde being the most abundant in concentration at both sites. The source apportionment of daytime OVOCs was conducted effectively using a photochemical age-based parameterization method. Biogenic and anthropogenic secondary sources were the main sources of formaldehyde, acetaldehyde, and acetone at both sites, with a total contribution of 46-82%; acetone also had a large regional-scale background contribution (36-38%); methanol and methyl ethyl ketone (MEK) were mainly derived from anthropogenic primary sources (35-55%) at both sites. In addition, the regional background levels of OVOCs measured in North China were shown to be much higher than those measured in South China. The calculation of the total O3 formation potential (OFP) of OVOCs highlights the comparable contributions from anthropogenic and biogenic sources in both Beijing and Shenzhen, indicating the important role of biogenic OVOC sources even in polluted environments. Since biogenic sources are already important but uncontrollable, anthropogenic emissions in China need to be restricted even more critically in the future.
Collapse
Affiliation(s)
- Xiao-Feng Huang
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Science and Technology Park, Nanshan District, Shenzhen, 518055, China
| | - Bin Zhang
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Science and Technology Park, Nanshan District, Shenzhen, 518055, China
| | - Shi-Yong Xia
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Science and Technology Park, Nanshan District, Shenzhen, 518055, China
| | - Yu Han
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Science and Technology Park, Nanshan District, Shenzhen, 518055, China
| | - Chuan Wang
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Science and Technology Park, Nanshan District, Shenzhen, 518055, China; Environmental Laboratory, PKU-HKUST Shenzhen-Hong Kong Institution, Lishui Road, Nanshan District, Shenzhen, 518057, China
| | - Guang-He Yu
- Environmental Laboratory, PKU-HKUST Shenzhen-Hong Kong Institution, Lishui Road, Nanshan District, Shenzhen, 518057, China.
| | - Ning Feng
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Science and Technology Park, Nanshan District, Shenzhen, 518055, China
| |
Collapse
|
3
|
Han Y, Huang X, Wang C, Zhu B, He L. Characterizing oxygenated volatile organic compounds and their sources in rural atmospheres in China. J Environ Sci (China) 2019; 81:148-155. [PMID: 30975317 DOI: 10.1016/j.jes.2019.01.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 01/22/2019] [Accepted: 01/23/2019] [Indexed: 06/09/2023]
Abstract
Oxygenated volatile organic compounds (OVOCs) are important precursors and products of atmospheric secondary pollution. The sources of OVOCs, however, are still quite uncertain, especially in the atmosphere with much pollution in China. To study the sources of OVOCs in rural atmospheres, a proton transfer reaction mass spectrometry (PTR-MS) was deployed at a northern rural site (WD) and a southern rural site (YMK) in China during the summer of 2014 and 2016, respectively. The continuous observation showed that the mean concentration of TVOCs (totally 17 VOCs) measured at WD (52.4 ppbv) was far higher than that at YMK (11.1 ppbv), and the OVOCs were the most abundant at both the two sites. The diurnal variations showed that local sources of OVOCs were still prominent at WD, while regional transport influenced YMK much. The photochemical age-based parameterization method was then used to quantitatively apportion the sources of ambient OVOCs. The anthropogenic primary sources at WD and YMK contributed less (2%-16%) to each OVOC species. At both the sites, the atmospheric background had a dominant contribution (~50%) to acetone and formic acid, while the anthropogenic secondary formation was the main source (~40%) of methanol and MEK. For acetaldehyde and acetic acid, the biogenic sources were their largest source (~40%) at WD, while the background (39%) and anthropogenic secondary formation (42%) were their largest sources at YMK, respectively. This study reveals the complexity of sources of OVOCs in China, which urgently needs explored further.
Collapse
Affiliation(s)
- Yu Han
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xiaofeng Huang
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
| | - Chuan Wang
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Bo Zhu
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Lingyan He
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| |
Collapse
|
4
|
Huang XF, Wang C, Zhu B, Lin LL, He LY. Exploration of sources of OVOCs in various atmospheres in southern China. Environ Pollut 2019; 249:831-842. [PMID: 30953945 DOI: 10.1016/j.envpol.2019.03.106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 03/25/2019] [Accepted: 03/25/2019] [Indexed: 06/09/2023]
Abstract
Oxygenated volatile organic compounds (OVOCs) are critical atmospheric ozone and secondary organic aerosol (SOA) precursors and radical sources, while understanding of OVOC sources in the atmosphere, especially with large anthropogenic emissions, still has large uncertainties. A high-sensitivity proton transfer reaction mass spectrometer (PTR-MS) was deployed in vastly different atmospheres in southern China, including an urban site (SZ-U), a regional site (NA-R), and a background site (NL-B). Four critical OVOCs, i.e., methanol, acetone, methyl ethyl ketone (MEK) and acetaldehyde, five groups of aromatic hydrocarbons, isoprene and acetonitrile were measured with a high time resolution. The featured relative abundance and diurnal variations of the OVOCs indicated that methanol, acetone and MEK had prominent contributions from urban industrial activities, while acetaldehyde was closely related to the photochemical formation at all three sites. The photochemical age-based parameterization method was improved locally and then applied to quantify different sources of daytime OVOCs: anthropogenic secondary and biogenic sources (together 60-73%) were always the dominant source for acetaldehyde in various atmospheres; in addition to a significant background for methanol, acetone and MEK, anthropogenic primary emissions (mostly industrial) were their dominant source at SZ-U (38-73%), while biogenic sources played the key role for them at NL-B (30-43%); biomass burning contributed a small fraction of 5-17% for the four OVOCs at the three sites.
Collapse
Affiliation(s)
- Xiao-Feng Huang
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Chuan Wang
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Bo Zhu
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Li-Liang Lin
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Ling-Yan He
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China.
| |
Collapse
|