1
|
Xiang W, Wang W, Hou C, Fan C, Lei T, Li J, Ge M. Secondary organic aerosols from oxidation of 1-methylnaphthalene: Yield, composition, and volatility. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170379. [PMID: 38280593 DOI: 10.1016/j.scitotenv.2024.170379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/21/2024] [Accepted: 01/21/2024] [Indexed: 01/29/2024]
Abstract
Alkyl-PAHs (APAHs) have been identified worldwide, which could rapidly react with chlorine and OH radicals in the atmosphere. In this study, a comprehensive investigation is conducted for SOA generated by a representative alkyl-naphthalene (1-methyl naphthalene, 1-MN) initiated by Cl, including yield, chemical composition, and volatility of SOA. To better understand 1-MN atmospheric oxidation, reaction mechanisms of 1MN with Cl atoms and OH radicals are proposed and compared under different nitrogen oxides (NOx) conditions. The SOA yields are comparable for Cl-initiated and OH-initiated reactions under high NOx conditions but increased in Cl-initiated reactions under low NOx conditions. The compounds with ten carbons are more abundant in Cl-initiated SOA, while compounds with nine carbons have higher intensity, suggesting that Cl caused ring-retained and alkyl-lost products and OH produces ring-broken and alkyl-retained compounds. The volatility of SOA is remarkably low, and SOA formed from Cl oxidation is slightly higher than that from OH oxidation. These results reveal that 1MN-derived SOA with OH and Cl radicals would have different physical-chemical properties and may play an important role in air quality and health effects.
Collapse
Affiliation(s)
- Wang Xiang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Chemistry Academy of Sciences Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weigang Wang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Chemistry Academy of Sciences Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Chunyan Hou
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Chemistry Academy of Sciences Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - CiCi Fan
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Chemistry Academy of Sciences Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ting Lei
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Chemistry Academy of Sciences Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Junling Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Maofa Ge
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Chemistry Academy of Sciences Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
2
|
Jung D, Soler R, de la Paz D, Notario A, Muñoz A, Ródenas M, Vera T, Borrás E, Borge R. Oxidation capacity changes in the atmosphere of large urban areas in Europe: Modelling and experimental campaigns in atmospheric simulation chambers. CHEMOSPHERE 2023; 341:139919. [PMID: 37611775 DOI: 10.1016/j.chemosphere.2023.139919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/30/2023] [Accepted: 08/20/2023] [Indexed: 08/25/2023]
Abstract
Air pollution is a major concern for human health and the environment. Consequently, environmental standards have become stricter to improve air quality. Thanks to this, the ambient levels of O3 precursors such as VOCs and NOX have decreased. However, O3 levels in Europe, especially during winter, have increased, potentially impacting on atmospheric oxidation capacity and the associated chemistry of tropospheric oxidants. In this work, we focus on recent changes in the oxidation capacity of urban atmospheres. The study is conducted with the results of the CMAQ modelling system with a regional resolution with 12 × 12 km2 across the entire European continent for the winter (January) and summer (July) of 2007 and 2015. The 2015 meteorological data is used for both years to emphasise emission changes during the studied period. We scrutinise the changes in ambient concentration levels of the main tropospheric oxidants (O3 and HOX radicals) in five representative cities, Valencia, Madrid, Milan, Berlin, and The Hague. The enhanced O3 formation in winter seems to be due to the low VOC/NOX ratio, while the opposite trend in summer may be related to a relatively high ratio. Additionally, photooxidation experiments are carried out in the EUPHORE chambers to study the effect of changes in NOX concentration and NO/NO2 ratio on the variation of the given oxidants at constant VOCs concentrations. For the baseline experiments, two scenarios are selected based on the model results of 2015: two representative winter and summer days of low and high pollution in Berlin and Madrid, respectively. The role of VOC/NOX and NO/NO2 ratios on atmospheric reactivity is discussed. As a result, it is first suggested that further decreases in ambient NOX levels are required to reduce ambient O3 levels. Moreover, additional factors should be considered when designing local-specific emission abatement strategies.
Collapse
Affiliation(s)
- Daeun Jung
- Environmental Modelling Laboratory, Department of Chemical & Environmental Engineering, Universidad Politécnica de Madrid (UPM), C/ José Gutiérrez Abascal 2, 28006, Madrid, Spain.
| | - Rubén Soler
- EUPHORE Labs., Atmospheric Chemistry Area, Fundación Centro de Estudios Ambientales del Mediterráneo (CEAM), 46980, Paterna, Spain
| | - David de la Paz
- Environmental Modelling Laboratory, Department of Chemical & Environmental Engineering, Universidad Politécnica de Madrid (UPM), C/ José Gutiérrez Abascal 2, 28006, Madrid, Spain
| | - Alberto Notario
- Universidad de Castilla-La Mancha, Physical Chemistry Department, Faculty of Chemical Science and Technologies, Ciudad Real, Spain
| | - Amalia Muñoz
- EUPHORE Labs., Atmospheric Chemistry Area, Fundación Centro de Estudios Ambientales del Mediterráneo (CEAM), 46980, Paterna, Spain
| | - Milagros Ródenas
- EUPHORE Labs., Atmospheric Chemistry Area, Fundación Centro de Estudios Ambientales del Mediterráneo (CEAM), 46980, Paterna, Spain
| | - Teresa Vera
- EUPHORE Labs., Atmospheric Chemistry Area, Fundación Centro de Estudios Ambientales del Mediterráneo (CEAM), 46980, Paterna, Spain
| | - Esther Borrás
- EUPHORE Labs., Atmospheric Chemistry Area, Fundación Centro de Estudios Ambientales del Mediterráneo (CEAM), 46980, Paterna, Spain
| | - Rafael Borge
- Environmental Modelling Laboratory, Department of Chemical & Environmental Engineering, Universidad Politécnica de Madrid (UPM), C/ José Gutiérrez Abascal 2, 28006, Madrid, Spain
| |
Collapse
|
3
|
Ye C, Liu Y, Yuan B, Wang Z, Lin Y, Hu W, Chen W, Li T, Song W, Wang X, Lv D, Gu D, Shao M. Low-NO-like Oxidation Pathway Makes a Significant Contribution to Secondary Organic Aerosol in Polluted Urban Air. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13912-13924. [PMID: 37669221 DOI: 10.1021/acs.est.3c01055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Anthropogenic pollutants can greatly mediate formation pathways and chemical compositions of secondary organic aerosol (SOA) in urban atmospheres. We investigated the molecular tracers for different types of SOA in PM2.5 under varying NO/NO2 conditions in Guangzhou using source analysis of particle-phase speciated organics obtained from an iodide chemical ionization mass spectrometer with a Filter Inlet for Gases and AEROsols (FIGAERO-I-CIMS). Results show that low-NO-like pathways (when NO/NO2 < 0.2) explained ∼75% of the total measured FIGAERO-OA during regional transport periods, which was enriched in more-oxidized C4-C6 non-nitrogenous compounds over ozone accumulation. Daytime high-NO chemistry played larger roles (38%) in local pollution episodes, with organic nitrates (ONs) and nitrophenols increasing with enhanced aerosol water content and nitrate fraction. Nighttime NO3-initiated oxidation, characterized by monoterpene-derived ONs, accounted for comparable percentages (10-12%) of FIGAERO-OA for both two periods. Furthermore, the presence of organosulfates (OSs) improves the understanding of the roles of aqueous-phase processes in SOA production. Carbonyl-derived OSs exhibited a preferential formation under conditions of high aerosol acidity and/or abundant sulfate, which correlated well with low-NO-like SOA. Our results demonstrate the importance of NO/NO2 ratios in controlling SOA compositions, as well as interactions between water content, aerosol acidity, and inorganic salts in gas-to-particle partitioning of condensable organics.
Collapse
Affiliation(s)
- Chenshuo Ye
- State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKL-ESPC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Guangdong Provincial Academy of Environmental Science, Guangzhou 510045, China
| | - Ying Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKL-ESPC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Bin Yuan
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| | - Zelong Wang
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| | - Yi Lin
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| | - Weiwei Hu
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Wei Chen
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Tiange Li
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Daqi Lv
- State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKL-ESPC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Dasa Gu
- Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong 999077, China
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong 999077, China
| | - Min Shao
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| |
Collapse
|
4
|
Hwang K, An JG, Loh A, Kim D, Choi N, Song H, Choi W, Yim UH. Mobile measurement of vehicle emission factors in a roadway tunnel: A concentration gradient approach. CHEMOSPHERE 2023; 328:138611. [PMID: 37023905 DOI: 10.1016/j.chemosphere.2023.138611] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 03/06/2023] [Accepted: 04/03/2023] [Indexed: 06/19/2023]
Abstract
Tunnels are the preferred experimental environments for estimating vehicle emission factors (EFs) under real-world driving conditions. In this study, online measurements of traffic-related air pollutants (including CO2, NOX, SO2, O3, particulate matter [PM], and volatile organic compounds [VOCs]) were conducted using a mobile laboratory in the Sujungsan Tunnel in Busan, Korea. Mobile measurements generated concentration profiles of the target exhaust emissions inside the tunnel. These data were used to produce a zonation of the tunnel, i.e., mixing and accumulation zones. There were differences between the CO2, SO2, and NOX profiles, and a starting point that was free from ambient air mixing effects could be set at 600 m from the tunnel entrance. The EFs of vehicle exhaust emissions were calculated using pollutant concentration gradients. The average EFs for CO2, NO, NO2, SO2, PM10, PM2.5, and ∑VOCs were 149,000, 380, 55, 29.2, 9.64, 4.33, and 16.7 mg km-1·veh-1, respectively. Among the VOC groups, alkanes contributed more than 70% of the VOC EF. Mobile measurement-derived EFs were validated using the conventional EFs from stationary measurements. The EF results from the mobile measurements matched those from the stationary measurements, while the absolute concentration differences between them implied complex aerodynamic movements of the target pollutants inside the tunnel. This study demonstrated the usefulness and advantages of applying mobile measurements in a tunnel environment and indicated the potential of the approach for observation-based policymaking.
Collapse
Affiliation(s)
- Kyucheol Hwang
- Oil and POPs Research Group, Korea Institute of Ocean Science and Technology, Geoje, 53201, Republic of Korea
| | - Joon Geon An
- Oil and POPs Research Group, Korea Institute of Ocean Science and Technology, Geoje, 53201, Republic of Korea
| | - Andrew Loh
- Oil and POPs Research Group, Korea Institute of Ocean Science and Technology, Geoje, 53201, Republic of Korea
| | - Donghwi Kim
- Oil and POPs Research Group, Korea Institute of Ocean Science and Technology, Geoje, 53201, Republic of Korea
| | - Narin Choi
- Oil and POPs Research Group, Korea Institute of Ocean Science and Technology, Geoje, 53201, Republic of Korea; Department of Ocean Science, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea
| | - Hangyeol Song
- Department of Environmental Atmospheric Sciences, Pukyong National University, Busan, 48513, Republic of Korea
| | - Wonsik Choi
- Department of Environmental Atmospheric Sciences, Pukyong National University, Busan, 48513, Republic of Korea.
| | - Un Hyuk Yim
- Oil and POPs Research Group, Korea Institute of Ocean Science and Technology, Geoje, 53201, Republic of Korea; Department of Ocean Science, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea.
| |
Collapse
|
5
|
Fu Y, Yan Y, Wei Z, Spinney R, Dionysiou DD, Vione D, Liu M, Xiao R. Overlooked Transformation of Nitrated Polycyclic Aromatic Hydrocarbons in Natural Waters: Role of Self-Photosensitization. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37327199 DOI: 10.1021/acs.est.3c02276] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Photochemical transformation is an important process that involves trace organic contaminants (TrOCs) in sunlit surface waters. However, the environmental implications of their self-photosensitization pathway have been largely overlooked. Here, we selected 1-nitronaphthalene (1NN), a representative nitrated polycyclic aromatic hydrocarbon, to study the self-photosensitization process. We investigated the excited-state properties and relaxation kinetics of 1NN after sunlight absorption. The intrinsic decay rate constants of triplet (31NN*) and singlet (11NN*) excited states were estimated to be 1.5 × 106 and 2.5 × 108 s-1, respectively. Our results provided quantitative evidence for the environmental relevance of 31NN* in waters. Possible reactions of 31NN* with various water components were evaluated. With the reduction and oxidation potentials of -0.37 and 1.95 V, 31NN* can be either oxidized or reduced by dissolved organic matter isolates and surrogates. We also showed that hydroxyl (•OH) and sulfate (SO4•-) radicals can be generated via the 31NN*-induced oxidation of inorganic ions (OH- and SO42-, respectively). We further investigated the reaction kinetics of 31NN* and OH- forming •OH, an important photoinduced reactive intermediate, through complementary experimental and theoretical approaches. The rate constants for the reactions of 31NN* with OH- and 1NN with •OH were determined to be 4.22 × 107 and 3.95 ± 0.01 × 109 M-1 s-1, respectively. These findings yield new insights into self-photosensitization as a pathway for TrOC attenuation and provide more mechanistic details into their environmental fate.
Collapse
Affiliation(s)
- Yifu Fu
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China
- Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China
| | - Yiqi Yan
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China
- Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China
| | - Zongsu Wei
- Centre for Water Technology (WATEC) & Department of Engineering, Aarhus University, Hangøvej 2, Aarhus N DK-8200, Denmark
| | - Richard Spinney
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Davide Vione
- Department of Chemistry, University of Turin, Via Pietro Giuria 5, Torino 10125, Italy
| | - Min Liu
- State Key Laboratory of Powder Metallurgy, School of Physics and Electronics, Central South University, Changsha 410083, China
| | - Ruiyang Xiao
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China
- Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China
| |
Collapse
|
6
|
Zhang Y, Li D, Ma Y, Dubois C, Wang X, Perrier S, Chen H, Wang H, Jing S, Lu Y, Lou S, Yan C, Nie W, Chen J, Huang C, George C, Riva M. Field Detection of Highly Oxygenated Organic Molecules in Shanghai by Chemical Ionization-Orbitrap. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:7608-7617. [PMID: 35594417 DOI: 10.1021/acs.est.1c08346] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Secondary organic aerosol, formed through atmospheric oxidation processes, plays an important role in affecting climate and human health. In this study, we conducted a comprehensive campaign in the megacity of Shanghai during the 2019 International Import Expo (EXPO), with the first deployment of a chemical ionization─Orbitrap mass spectrometer for ambient measurements. With the ultrahigh mass resolving power of the Orbitrap mass analyzer (up to 140,000 Th/Th) and capability in dealing with massive spectral data sets by positive matrix factorization, we were able to identify the major gas-phase oxidation processes leading to the formation of oxygenated organic molecules (OOM) in Shanghai. Nine main factors from three independent sub-range analysis were identified. More than 90% of OOM are of anthropogenic origin and >60% are nitrogen-containing molecules, mainly dominated by the RO2 + NO and/or NO3 chemistry. The emission control during the EXPO showed that even though the restriction was effectual in significantly lowering the primary pollutants (20-70% decrease), the secondary oxidation products responded less effectively (14% decrease), or even increased (50 to >200%) due to the enhancement of ozone and the lowered condensation sink, indicating the importance of a stricter multi-pollutant coordinated strategy in primary and secondary pollution mitigation.
Collapse
Affiliation(s)
- Yanjun Zhang
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Dandan Li
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
| | - Yingge Ma
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Clement Dubois
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
| | - Xinke Wang
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
| | - Sebastien Perrier
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
| | - Hui Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Institute of Atmospheric Sciences, Fudan University, Shanghai 200438, China
| | - Hongli Wang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Sheng'ao Jing
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Yiqun Lu
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Shengrong Lou
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Chao Yan
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Wei Nie
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu Province 210093, China
| | - Jianmin Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Institute of Atmospheric Sciences, Fudan University, Shanghai 200438, China
| | - Cheng Huang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Christian George
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
| | - Matthieu Riva
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
| |
Collapse
|
7
|
Wang K, Wang W, Fan C, Li J, Lei T, Zhang W, Shi B, Chen Y, Liu M, Lian C, Wang Z, Ge M. Reactions of C 12-C 14 n-Alkylcyclohexanes with Cl Atoms: Kinetics and Secondary Organic Aerosol Formation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:4859-4870. [PMID: 35319183 DOI: 10.1021/acs.est.1c08958] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Long-chain alkanes are a type of intermediate volatility organic compound (IVOC) in the atmosphere and a potential source of secondary organic aerosols (SOAs). C12-C14 n-alkylcyclohexanes are important compositions of IVOCs, with considerable concentrations and emission rates. The reaction rate constants and SOA formation of the reactions of C12-C14 n-alkylcyclohexanes with Cl atoms were investigated in the present study. The reaction rate constants of the long-chain alkanes obtained via the relative-rate method at 298 ± 0.2 K (in units of ×10-10 cm3 molecule-1 s-1) were as follows: khexylcyclohexane = 5.11 ± 0.28, kheptylcyclohexane = 5.56 ± 0.30, and koctylcyclohexane = 5.74 ± 0.31. The gas-phase products of the reactions were identified as mainly small molecules of aldehydes, ketones, and acids. The particle-phase products were mostly monomers and oligomers, but there were still trimers even under high-NOx conditions. Moreover, under high-NOx conditions (urban atmosphere), the SOA yields of hexylcyclohexane are higher than that under low-NOx conditions (remote atmosphere), indicating that more attention should be given to the SOA formation of Cl-initiated n-alkylcyclohexane oxidations in polluted regions. This research can further clarify the oxidation processes and SOA formation of n-alkylcyclohexanes in the atmosphere.
Collapse
Affiliation(s)
- Ke Wang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Weigang Wang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Cici Fan
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Junling Li
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- Chinese Research Academy of Environmental Sciences, Beijing 100012, P. R. China
| | - Ting Lei
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Wenyu Zhang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Bo Shi
- Hebei Normal University, Shijiazhuang 050010, P. R. China
| | - Yan Chen
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Mingyuan Liu
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chaofan Lian
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Zhe Wang
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology, Hong Kong SAR 999077, P. R. China
| | - Maofa Ge
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| |
Collapse
|
8
|
Yang Z, Tsona NT, George C, Du L. Nitrogen-Containing Compounds Enhance Light Absorption of Aromatic-Derived Brown Carbon. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:4005-4016. [PMID: 35192318 DOI: 10.1021/acs.est.1c08794] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The formation of secondary brown carbon (BrC) is chemically complex, leading to an unclear relationship between its molecular composition and optical properties. Here, we present an in-depth investigation of molecular-specific optical properties and aging of secondary BrC produced from the photooxidation of ethylbenzene at varied NOx levels for the first time. Due to the pronounced formation of unsaturated products, the mass absorption coefficient (MAC) of ethylbenzene secondary organic aerosols (ESOA) at 365 nm was higher than that of biogenic SOA by a factor of 10. A high NOx level ([ethylbenzene]0/[NOx]0 < 10 ppbC ppb-1) was found to significantly increase the average MAC300-700nm of ESOA by 0.29 m2 g-1. The data from two complementary high-resolution mass spectrometers and quantum chemical calculations suggested that nitrogen-containing compounds were largely responsible for the enhanced light absorption of high-NOx ESOA, and multifunctional nitroaromatic compounds (such as C8H9NO3 and C8H9NO4) were identified as important BrC chromophores. High-NOx ESOA underwent photobleaching upon direct exposure to ultraviolet light. Photolysis did not lead to the significant decomposition of C8H9NO3 and C8H9NO4, indicating that nitroaromatic compounds may serve as relatively stable nitrogen reservoirs and would effectively absorb solar radiation during the daytime.
Collapse
Affiliation(s)
- Zhaomin Yang
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Narcisse T Tsona
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Christian George
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, Villeurbanne F-69626, France
| | - Lin Du
- Environment Research Institute, Shandong University, Qingdao 266237, China
| |
Collapse
|
9
|
Yang Z, Du L, Li Y, Ge X. Secondary organic aerosol formation from monocyclic aromatic hydrocarbons: insights from laboratory studies. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:351-379. [PMID: 35171163 DOI: 10.1039/d1em00409c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Monocyclic aromatic hydrocarbons (MAHs) are key anthropogenic pollutants and often dominate the volatile organic compound emissions and secondary organic aerosol (SOA) formation especially in the urban atmosphere. To evaluate the environmental impacts of SOA formed from the oxidation of MAHs (aromatic SOA), it is of great importance to elucidate their chemical composition, formation mechanism, and physicochemical properties under various atmospheric conditions. Here we seek to compile a common framework for the current studies on aromatic SOA formation and summarize the knowledge on what has been primarily learned from laboratory studies. This review begins with a brief summary of MAHs' emission characteristics, followed by an overview of atmospheric degradation mechanisms for MAHs as well as gas- and particle-phase reactions involving aromatic SOA formation. SOA formation processes highlighted in this review are complex and depend highly on environmental conditions, posing a substantial challenge for theoretical description of aromatic SOA formation. Therefore, the following issues are further discussed in detail: the response of gas-phase chemistry and aromatic SOA mass yield as well as composition to NOx levels, particle-phase reactions and molecular characterization of aromatic SOA in the presence of acidic sulfate, and physicochemical processes of SOA formation involving gas- or particle-phase water. Building on this current understanding, available experimental studies on the effects of environmental conditions were explored. A brief description of the atmospheric importance of aromatic SOA including their optical properties and health influences is also presented. Finally, we highlight the current challenges in laboratory studies and outline directions for future aromatic SOA research.
Collapse
Affiliation(s)
- Zhaomin Yang
- Environment Research Institute, Shandong University, 266000, Qingdao, China.
| | - Lin Du
- Environment Research Institute, Shandong University, 266000, Qingdao, China.
| | - Yongjie Li
- Department of Civil and Environmental Engineering, and Centre for Regional Oceans, Faculty of Science and Technology, University of Macau, Macau, China
| | - Xinlei Ge
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, 210044, Nanjing, China
| |
Collapse
|
10
|
Barber VP, Kroll JH. Chemistry of Functionalized Reactive Organic Intermediates in the Earth's Atmosphere: Impact, Challenges, and Progress. J Phys Chem A 2021; 125:10264-10279. [PMID: 34846877 DOI: 10.1021/acs.jpca.1c08221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The gas-phase oxidation of organic compounds is an important chemical process in the Earth's atmosphere. It governs oxidant levels and controls the production of key secondary pollutants, and hence has major implications for air quality and climate. Organic oxidation is largely controlled by the chemistry of a few reactive intermediates, namely, alkyl (R) radicals, alkoxy (RO) radicals, peroxy (RO2) radicals, and carbonyl oxides (R1R2COO), which may undergo a number of unimolecular and bimolecular reactions. Our understanding of these intermediates, and the reaction pathways available to them, is based largely on studies of unfunctionalized intermediates, formed in the first steps of hydrocarbon oxidation. However, it has become increasingly clear that intermediates with functional groups, which are generally formed later in the oxidation process, can exhibit fundamentally different reactivity than unfunctionalized ones. In this Perspective, we explore the unique chemistry available to functionalized organic intermediates in the Earth's atmosphere. After a brief review of the canonical chemistry available to unfunctionalized intermediates, we discuss how the addition of functional groups can introduce new reactions, either by changing the energetics or kinetics of a given reaction or by opening up new chemical pathways. We then provide examples of atmospheric reaction classes that are available only to functionalized intermediates. Some of these, such as unimolecular H-shift reactions of RO2 radicals, have been elucidated only relatively recently, and can have important impacts on atmospheric chemistry (e.g., on radical cycling or organic aerosol formation); it seems likely that other, as-yet undiscovered reactions of (multi)functional intermediates may also exist. We discuss the challenges associated with the study of the chemistry of such intermediates and review novel experimental and theoretical approaches that have recently provided (or hold promise for providing) new insights into their atmospheric chemistry. The continued use and development of such techniques and the close collaboration between experimentalists and theoreticians are necessary for a complete, detailed understanding of the chemistry of functionalized intermediates and their impact on major atmospheric chemical processes.
Collapse
Affiliation(s)
- Victoria P Barber
- Departments of Civil and Environmental Engineering and Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Jesse H Kroll
- Departments of Civil and Environmental Engineering and Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| |
Collapse
|