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He S, Liu Y, Song M, Li X, Lu S, Chen T, Mu Y, Lou S, Shi X, Qiu X, Zhu T, Zhang Y. Insights into the Peroxide-Bicyclic Intermediate Pathway of Aromatic Photooxidation: Experimental Yields and NO x-Dependency of Ring-Opening and Ring-Retaining Products. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20657-20668. [PMID: 38029335 DOI: 10.1021/acs.est.3c05304] [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: 12/01/2023]
Abstract
Aromatic hydrocarbons are important contributors to the formation of ozone and secondary organic aerosols in urban environments. The different parallel pathways in aromatic oxidation, however, remain inadequately understood. Here, we investigated the production yields and chemical distributions of gas-phase tracer products during the photooxidation of alkylbenzenes at atmospheric OH levels with NOx present using high-resolution mass spectrometers. The peroxide-bicyclic intermediate pathway emerged as the major pathway in aromatic oxidation, accounting for 52.1 ± 12.6%, 66.1 ± 16.6%, and 81.4 ± 24.3% of the total OH oxidation of toluene, m-xylene, and 1,3,5-trimethylbenzene, respectively. Notably, the yields of bicyclic nitrates produced from the reactions of bicyclic peroxy radicals (BPRs) with NO were considerably lower (3-5 times) than what the current mechanism predicted. Alongside traditional ring-opening products formed through the bicyclic pathway (dicarbonyls and furanones), we identified a significant proportion of carbonyl olefinic acids generated via the 1,5-aldehydic H-shift occurring in subsequent reactions of BPRs + NO, contributing 4-7% of the carbon flow in aromatic oxidation. Moreover, the observed NOx-dependencies of ring-opening and ring-retaining product yields provide insights into the competitive nature of reactions involving BPRs with NO, HO2, and RO2, which determine the refined product distributions and offer an explanation for the discrepancies between the experimental and model-based results.
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Affiliation(s)
- Shuyu He
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Ying Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Mengdi Song
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xin Li
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Sihua Lu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Tianzeng Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yujing Mu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, 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
| | - Xiaodi Shi
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xinghua Qiu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Tong Zhu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yuanhang Zhang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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Fu Z, Ma F, Liu Y, Yan C, Huang D, Chen J, Elm J, Li Y, Ding A, Pichelstorfer L, Xie HB, Nie W, Francisco JS, Zhou P. An overlooked oxidation mechanism of toluene: computational predictions and experimental validations. Chem Sci 2023; 14:13050-13059. [PMID: 38023500 PMCID: PMC10664553 DOI: 10.1039/d3sc03638c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/26/2023] [Indexed: 12/01/2023] Open
Abstract
Secondary organic aerosols (SOAs) influence the Earth's climate and threaten human health. Aromatic hydrocarbons (AHs) are major precursors for SOA formation in the urban atmosphere. However, the revealed oxidation mechanism dramatically underestimates the contribution of AHs to SOA formation, strongly suggesting the importance of seeking additional oxidation pathways for SOA formation. Using toluene, the most abundant AHs, as a model system and the combination of quantum chemical method and field observations based on advanced mass spectrometry, we herein demonstrate that the second-generation oxidation of AHs can form novel epoxides (TEPOX) with high yield. Such TEPOX can further react with H2SO4 or HNO3 in the aerosol phase to form less-volatile compounds including novel non-aromatic and ring-retaining organosulfates or organonitrates through reactive uptakes, providing new candidates of AH-derived organosulfates or organonitrates for future ambient observation. With the newly revealed mechanism, the chemistry-aerosol box modeling revealed that the SOA yield of toluene oxidation can reach up to 0.35, much higher than 0.088 based on the original mechanism under the conditions of pH = 2 and 0.1 ppbv NO. This study opens a route for the formation of reactive uptake SOA precursors from AHs and significantly fills the current knowledge gap for SOA formation in the urban atmosphere.
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Affiliation(s)
- Zihao Fu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology Dalian 116024 China
| | - Fangfang Ma
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology Dalian 116024 China
| | - Yuliang Liu
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University Nanjing 210023 China
| | - Chao Yan
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University Nanjing 210023 China
| | - Dandan Huang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences Shanghai China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology Dalian 116024 China
| | - Jonas Elm
- Department of Chemistry, iClimate, Aarhus University Langelandsgade 140 DK-8000 Aarhus C Denmark
| | - Yuanyuan Li
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University Nanjing 210023 China
| | - Aijun Ding
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University Nanjing 210023 China
| | - Lukas Pichelstorfer
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki P. O. Box 64 FIN-00014 Helsinki Finland
- pi-numerics Wallbachsiedlung 28 5202 Neumarkt am W. Austria
| | - Hong-Bin Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology Dalian 116024 China
| | - Wei Nie
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University Nanjing 210023 China
| | - Joseph S Francisco
- Department of Earth and Environmental Science, University of Pennsylvania Philadelphia PA USA 19104-6316
| | - Putian Zhou
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki P. O. Box 64 FIN-00014 Helsinki Finland
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Yu Z, Wei Z, Zhang Z, Li Z, Zhang P, Yang B, Shu J, Wang H, Yan Z. Insight into the crucial reason causing the difference in secondary organic aerosol yields of monocyclic aromatic hydrocarbons with different methyl substituent numbers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 898:166353. [PMID: 37597565 DOI: 10.1016/j.scitotenv.2023.166353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/13/2023] [Accepted: 08/15/2023] [Indexed: 08/21/2023]
Abstract
The secondary organic aerosol (SOA) yield of toluene photooxidation was reported to substantially higher than that of trimethylbenzene due to the effect of the number of methyl substituents. However, the intrinsic mechanism for this disparity is not clear enough. In this study, a highly-sensitive thermal-desorption photoinduced associative ionization mass spectrometer (TD-PAI-MS) was used to real-time characterize the molecular composition and its evolution of the SOA generated from the photooxidation of toluene and 1,2,3-trimethylbenzene (1,2,3-TMB) in a smog chamber. In the new particle formation (NPF) stage, toluene generated more variety of nucleation precursors, such as benzaldehyde (MW 106) and benzoic acid (MW 122), resulting in a much higher nucleation rate and SOA number concentration. In the SOA growth/aging stage, the key SOA components of toluene were mainly dialdehydes, e.g., 2-oxopropanedial (MW 86) and 4-oxopent-2-enedial (MW 112), which played an important role in the formation of highly oxidized species (HOS) through oligomerization or cyclization reactions. In contrast, due to the presence of more methyl groups, 1,2,3-TMB was inclined to produce ketones, e.g., 2,3-butanedione (MW 86) and 3-methyl-4-oxopent-2-enal (MW 112), which would be cleaved into high-volatility low molecular compounds, e.g., acetic acid, through fragmentation. Taken together, relative to 1,2,3-TMB, the higher nucleation rate during NPF and the significant oligomerization/functionalization process during SOA growth are thought to be the major reasons resulting in the higher SOA yield of toluene. This work provides a reference for the insight into the different SOA yields of monocyclic aromatic hydrocarbons (MAHs) through further revealing the SOA formation mechanism during toluene and 1,2,3-TMB photooxidation.
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Affiliation(s)
- Zhangqi Yu
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
| | - Zhiyang Wei
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
| | - Zhongshen Zhang
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
| | - Zhen Li
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
| | - Peng Zhang
- State Key Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China.
| | - Bo Yang
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China.
| | - Jinian Shu
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
| | - Haijie Wang
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
| | - Zitao Yan
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
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Chen T, Liu J, Chu B, Ge Y, Zhang P, Ma Q, He H. Combined Smog Chamber/Oxidation Flow Reactor Study on Aging of Secondary Organic Aerosol from Photooxidation of Aromatic Hydrocarbons. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13937-13947. [PMID: 37691473 DOI: 10.1021/acs.est.3c04089] [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: 09/12/2023]
Abstract
Secondary organic aerosol (SOA) is a significant component of atmospheric fine particulate matter (PM2.5), and their physicochemical properties can be significantly changed in the aging process. In this study, we used a combination consisting of a smog chamber (SC) and oxidation flow reactor (OFR) to investigate the continuous aging process of gas-phase organic intermediates and SOA formed from the photooxidation of toluene, a typical aromatic hydrocarbon. Our results showed that as the OH exposure increased from 2.6 × 1011 to 6.3 × 1011 molecules cm-3 s (equivalent aging time of 2.01-4.85 days), the SOA mass concentration (2.9 ± 0.05-28.7 ± 0.6 μg cm-3) and corrected SOA yield (0.073-0.26) were significantly enhanced. As the aging process proceeds, organic acids and multiple oxygen-containing oxidation products are continuously produced from the photochemical aging process of gas-phase organic intermediates (mainly semi-volatile and intermediate volatility species, S/IVOCs). The multigeneration oxidation products then partition to the aerosol phase, while functionalization of SOA rather than fragmentation dominated in the photochemical aging process, resulting in much higher SOA yield after aging compared to that in the SC. Our study indicates that SOA yields as a function of OH exposure should be considered in air quality models to improve SOA simulation, and thus accurately assess the impact on SOA properties and regional air quality.
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Affiliation(s)
- Tianzeng Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jun Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Biwu Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanli Ge
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Peng Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingxin Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Tiusanen A, Ruiz-Jimenez J, Hartonen K, Wiedmer SK. Analytical methodologies for oxidized organic compounds in the atmosphere. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:1263-1287. [PMID: 37491999 DOI: 10.1039/d3em00163f] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Oxidized compounds in the atmosphere can occur as emitted primary compounds or as secondary products when volatile emitted precursors react with various oxidants. Due to the presence of polar functional groups, their vapor pressures decrease, and they condense onto small particles. Thereby, they have an effect on climate change by the formation of clouds and scattering solar radiation. The particles and oxidized compounds themselves can cause serious health problems when inhaled. Therefore, it is of utmost importance to study oxidized compounds in the atmosphere. Much ongoing research is focused on the discovery of new oxidized substances and on the evaluation of their sources and factors influencing their formation. Monitoring biogenic and anthropogenic primary oxidized compounds or secondary oxidized products in chamber experiments or field campaigns is common. New discoveries have been reported, including various oxidized compounds and a new group of compounds called highly oxidized organic molecules (HOMs). Analytics of HOMs are mainly focused on chromatography and high-resolution mass spectrometry employing chemical ionization for identifying and quantifying compounds at low concentrations. Oxidized compounds can also be monitored by spectrophotometric methods in which the determinations of total amounts are based on functional groups. This review highlights recent findings on oxidized organic compounds in the atmosphere and analytical methodologies used for their detection and quantification. The discussion includes gas and liquid chromatographic methods, sampling, extraction, concentration, and derivatization procedures involved, as well as mass spectrometric and spectrophotometric methods.
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Affiliation(s)
- Aleksi Tiusanen
- Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
| | - Jose Ruiz-Jimenez
- Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
- Institute for Atmospheric and Earth System Research, Chemistry, Faculty of Science, P.O. Box 55, FI-00014 University of Helsinki, Finland
| | - Kari Hartonen
- Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
- Institute for Atmospheric and Earth System Research, Chemistry, Faculty of Science, P.O. Box 55, FI-00014 University of Helsinki, Finland
| | - Susanne K Wiedmer
- Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
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Liang C, Wang S, Hu R, Huang G, Xie J, Zhao B, Li Y, Zhu W, Guo S, Jiang J, Hao J. Molecular tracers, mass spectral tracers and oxidation of organic aerosols emitted from cooking and fossil fuel burning sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 868:161635. [PMID: 36657674 DOI: 10.1016/j.scitotenv.2023.161635] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
Secondary organic aerosol (SOA) composes a substantial fraction of atmospheric particles, yet the formation and aging mechanism of SOA remains unclear. Here we investigate the initial oxidation of primary organic aerosol (POA) and further aging of SOA in winter Beijing by using aerosol mass spectrometer (AMS) measurements along with offline molecular tracer analysis. Multilinear engine (ME-2) source apportionment was conducted to capture the characteristic of source-related SOA, and connect them with specific POA. Our results show that urban cooking and fossil fuel burning sources contribute significantly (17 % and 20 %) to total organic aerosol (OA) in winter Beijing. Molecular tracer analysis by two-dimensional gas chromatography-time-of-flight mass spectrometer (GC × GC-ToF-MS) reveals that cooking SOA (CSOA) is produced through both photooxidation and aqueous-phase processing, while less oxidized SOA (LO-SOA) is the photooxidation product of fossil fuel burning OA (FFOA) and may experience aqueous-phase aging to form more-oxidized oxygenated OA (MO-OOA). Furthermore, CHOm/z 69 and CHOm/z 85 are mass spectral tracers indicating the initial photooxidation, while CHO2+ and C2H2O2+ imply further aqueous-phase aging of OA. Tracer analysis indicates that the formation of diketones is involved in the initial photooxidation of POA, while the formation of glyoxal and diacids is involved in the further aqueous-phase aging of SOA.
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Affiliation(s)
- Chengrui Liang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Shuxiao Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.
| | - Ruolan Hu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Guanghan Huang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Jinzi Xie
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Bin Zhao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Yuyang Li
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Wenfei Zhu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Song Guo
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Jingkun Jiang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Jiming Hao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
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Wang H, Zou Y, Wang W, Zhang Y, Mailhot G, Li J, Wu F, Luo L. Quantitative structure-activity relationship for the photooxidation of aromatic micro-pollutants induced by graphene oxide in water. CHEMOSPHERE 2023; 315:137781. [PMID: 36623604 DOI: 10.1016/j.chemosphere.2023.137781] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 12/28/2022] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
The photocatalytic degradation behavior of aromatic micro-pollutants (AMPs) exhibits complexity and uncertainty, which mainly depends on the properties of different substituents on benzene. And with similar catalytic reaction substrates, the reaction rate constant could reveal the influence of different characteristics of molecular structure in a specific system. Therefore, the photooxidation pseudo first-order kinetic rate constants (kobs) of 30 AMPs were experimentally determined in Photo-GO system. A quantitative structure-activity relationship (QSAR) model for predicting the photooxidation reaction of AMPs has been developed by stepwise multiple linear regression (MLR) method, based on the lg kobs and representative molecule descriptors (20 in total) including physicochemical, quantum chemical and electrostatic descriptors. Afterwards, Radj2, QLOO2, and Qext2 were calculated as 0.870, 0.841, and 0.732 respectively, which exhibited the excellent goodness-of-fit, robustness, and predictability of the QSAR model, indicating its great prediction ability for photooxidation behavior of AMPs. Meanwhile, during the photooxidation process of AMPs with GO, the model revealed that the one-electron oxidation potential (Eox), molecular dipole moment (μ), and number of hydrogen bond donors (#HD) were the most important molecular structural parameters, which showed that the single electron transfer pathway and adsorption were as the significant steps. Additionally, the Hammett correlation showed that photooxidation of AMPs in Photo-GO system is of typical electrophilic reactions, which demonstrated that the electron-donating substituents could promote the photooxidation of AMPs. The QSAR model was constructed and evaluated to perform the prediction of AMPs reaction kinetics, which provided a guidance for the study of the mechanism and selective oxidation of AOPs photooxidation system based on GO.
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Affiliation(s)
- Hao Wang
- Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China; Hubei Academy of Ecological and Environmental Sciences, Wuhan, 430072, PR China
| | - Yongrong Zou
- Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China
| | - Wenyu Wang
- Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China
| | - Yihui Zhang
- Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China
| | - Gilles Mailhot
- Université Clermont Auvergne, CNRS, Institut de Chimie de Clermont-Ferrand (ICCF) UMR 6296, F-63000, Clermont-Ferrand, France
| | - Jinjun Li
- Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China
| | - Feng Wu
- Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China.
| | - Liting Luo
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.
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8
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Liu Y, Zhou M, Lu K. Compilation of reaction kinetics parameters determined in the Key Development Project for Air Pollution Formation Mechanism and Control Technologies in China. J Environ Sci (China) 2023; 123:327-340. [PMID: 36521996 DOI: 10.1016/j.jes.2022.06.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 06/14/2022] [Accepted: 06/14/2022] [Indexed: 06/17/2023]
Abstract
A compilation of new advances made in the research field of laboratory reaction kinetics in China's Key Development Project for Air Pollution Formation Mechanism and Control Technologies was presented. These advances are grouped into six broad, interrelated categories, including volatile organic compound (VOC) oxidation, secondary organic aerosol (SOA) formation, new particle formation (NPF) and gas-particle partitioning, ozone chemistry, model parameters, and secondary inorganic aerosol (SIA) formation, highlighting the laboratory work done by Chinese researchers. For smog chamber applications, the current knowledge gained from laboratory studies is reviewed, with emphasis on summarizing the oxidation mechanisms of long-chain alkanes, aromatics, alkenes, aldehydes/ketones in the atmosphere, SOA formation from anthropogenic emission sources, and oxidation of aromatics, isoprene, and limonene, as well as SIA formation. For flow tube applications, atmospheric oxidation mechanisms of toluene and methacrolein, SOA formation from limonene oxidation by ozone, gas-particle partitioning of peroxides, and sulfuric acid-water (H2SO4-H2O) binary nucleation, methanesulfonic acid-water (MSA-H2O) binary nucleation, and sulfuric acid-ammonia-water (H2SO4-NH3-H2O) ternary nucleation are discussed.
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Affiliation(s)
- Yuehui Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, State Environmental Protection Key Laboratory of Atmospheric Ozone Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Ming Zhou
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, State Environmental Protection Key Laboratory of Atmospheric Ozone Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Keding Lu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, State Environmental Protection Key Laboratory of Atmospheric Ozone Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
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9
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Illmann N, Patroescu-Klotz I, Wiesen P. Organic acid formation in the gas-phase ozonolysis of α,β-unsaturated ketones. Phys Chem Chem Phys 2022; 25:106-116. [PMID: 36476818 DOI: 10.1039/d2cp03210d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Organic acids are key species in determining the radiative properties of the atmosphere due to their contribution to particle formation. Reported discrepancies between field measurements and modelling suggest significant missing sources. Herein, we present a mechanistic investigation on the gas-phase ozonolysis of ethyl vinyl ketone (EVK, 1-penten-3-one), which we chose as a model compound for α,β-unsaturated ketones. Experiments were performed in a 1080 L quartz-glass reaction chamber (QUAREC) at 990 ± 15 mbar and 298 ± 2 K (r. h. ≪ 0.1%) and analysed via long-path FTIR spectrometry and PTR-ToF-MS. The experiments were performed in the presence of an excess of CO to suppress the chemistry of OH radicals. For a comprehensive picture, in selected experiments, SO2 was also added to the reaction system to scavenge the stabilized Criegee intermediates (sCIs) and to investigate their formation yield. Combining the results of both set-ups allowed us to quantify 2-oxobutanal, for which we report vapour-phase FTIR spectra. In addition, we introduce the first-ever infrared spectra of perpropionic acid, which was also positively identified in the EVK + O3 system. A detailed analysis of the experimental findings allowed us to link the identified reaction products (acetaldehyde, ethyl hydroperoxide, and perpropionic acid) to known bimolecular reactions of RO2 radicals. Thereby, it is shown that the EVK + O3 reaction yields formic acid, HC(O)OH, and propionic acid, C2H5C(O)OH, and their formation is not covered by mechanisms reported in the literature. Three different pathways accounting for their formation from chemically activated CIs are proposed and possible implications for the ozonolysis of α,β-unsaturated ketones in the atmosphere are discussed.
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Affiliation(s)
- Niklas Illmann
- Institute for Atmospheric and Environmental Research, Bergische Universität Wuppertal, Gaußstraße 20, 42119 Wuppertal, Germany.
| | - Iulia Patroescu-Klotz
- Institute for Atmospheric and Environmental Research, Bergische Universität Wuppertal, Gaußstraße 20, 42119 Wuppertal, Germany.
| | - Peter Wiesen
- Institute for Atmospheric and Environmental Research, Bergische Universität Wuppertal, Gaußstraße 20, 42119 Wuppertal, Germany.
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10
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Xiao Y, Hu M, Li X, Zong T, Xu N, Hu S, Zeng L, Chen S, Song Y, Guo S, Wu Z. Aqueous secondary organic aerosol formation attributed to phenols from biomass burning. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 847:157582. [PMID: 35882337 DOI: 10.1016/j.scitotenv.2022.157582] [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: 06/12/2022] [Revised: 07/17/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
Biomass burning emits large quantities of phenols, which readily partition into the atmospheric aqueous phase and subsequently may react to produce aqueous secondary organic aerosol (aqSOA). For the first time, we quantitatively explored the influence of phenols emitted from biomass burning on aqSOA formation in the winter of Beijing. A typical haze episode associated with significant aqSOA formation was captured. During this episode, aqueous-phase processing of biomass burning promoted aqSOA formation was identified. Furthermore, high-resolution mass spectrum analysis provided molecular-level evidence of the phenolic aqSOA tracers. Estimation of aqSOA formation rate (RaqSOA) with compiled laboratory kinetic data indicated that biomass-burning phenols can efficiently produce aqSOA at midday, with RaqSOA of 0.42 μg m-3 h-1 accounting for 15 % of total aqSOA formation rate. The results highlight that aqSOA formation of phenols contributes the haze pollution. This implies the importance of regional joint control of biomass burning to mitigate the heavy haze.
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Affiliation(s)
- Yao Xiao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Min Hu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
| | - Xiao Li
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Taomou Zong
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Nan Xu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Shuya Hu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Limin Zeng
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Shiyi Chen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yu Song
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Song Guo
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Zhijun Wu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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11
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Zhang X, Kong Y, Cao J, Li H, Gao R, Zhang Y, Wang K, Li Y, Ren Y, Wang W. A sensitive simultaneous detection approach for the determination of 30 atmospheric carbonyls by 2,4-dinitrophenylhydrazine derivatization with HPLC-MS technique and its preliminary application. CHEMOSPHERE 2022; 303:134985. [PMID: 35588876 DOI: 10.1016/j.chemosphere.2022.134985] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 05/07/2022] [Accepted: 05/13/2022] [Indexed: 06/15/2023]
Abstract
Atmospheric carbonyls are important precursors of PM2.5 and ground-level ozone, and some carbonyls are toxic and harmful; thus, it is crucial to obtain accurate information on the ambient levels of carbonyls. However, the detection of carbonyls is difficult due to their relatively higher reactivities and chemical instabilities; therefore, accurate determination of atmospheric carbonyls is important. In this study, an analytical method for atmospheric carbonyls with high concentration or reactivity was developed, the precursor ion of each carbonyl compound was selected, and the declustering potential (DP) and entrance potential (EP) for each precursor ion were optimized. A 2,4-dinitrophenylhydrazine cartridge derivatization-high performance liquid chromatography/atmospheric pressure chemical ionization-mass spectrometry (DNPH-HPLC/APCI-MS) method for the determination of 30 carbonyls was established. The results showed that the linear range of 24 carbonyls was 1.2-600 ng/mL, while other 6 carbonyls was 1.2-300 ng/mL, and the detection limits of 30 carbonyls ranged from 0.092 to 0.947 ng/mL (0.005-0.049 μg/m3 with an ambient air sampling volume of 96 L). The intra-day and inter-day repeatability ranges were 0.55-4.20% and 1.40-12.48%, respectively. A preliminary application of the method was carried out in the urban area of Beijing in spring and summer of 2021, and it was found that the mean total mass concentration of 30 carbonyls was 35.894 μg/m3. This study provided additional concentration information for 14 atmospheric carbonyls, including mono-, di-, oxygen-containing and heterocyclic carbonyls, which accounted for 38% and 35% of the total mass concentration and OH radical reactivities of 30 carbonyls, respectively. This is the first investigation of simultaneous quantitative analysis of multiple atmospheric carbonyls based on commercial standard derivatives. The optimized method could provide more comprehensive information for atmospheric carbonyls and further support research concerning the role of chemical reaction processes and health effects than traditional measuring techniques.
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Affiliation(s)
- Xin Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Yuxue Kong
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Science, China University of Petroleum, Beijing 102249, China
| | - Juan Cao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Hong Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Rui Gao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yujie Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Kexin Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; School of Resources and Environment, Yangtze University, Wuhan 430100, China
| | - Yunfeng Li
- School of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China
| | - Yanqin Ren
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Wenxing Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Environment Research Institute, Shandong University, Qingdao 266237, China
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12
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Zhang X, Wu Z, He Z, Zhong X, Bi F, Li Y, Gao R, Li H, Wang W. Spatiotemporal patterns and ozone sensitivity of gaseous carbonyls at eleven urban sites in southeastern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 824:153719. [PMID: 35149078 DOI: 10.1016/j.scitotenv.2022.153719] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/30/2022] [Accepted: 02/03/2022] [Indexed: 06/14/2023]
Abstract
Gaseous carbonyls are essential trace gases for tropospheric chemistry and contribute significantly to the formation of ambient air ozone (O3) in densely populated regions, especially in China. Pollution characterization and the analysis of O3, nitrogen oxides, and volatile organic compounds (O3-NOX-VOCs) sensitivities of carbonyls were investigated from October 22 to 28, 2018 at eleven urban sites in nine cities in Fujian Province, southeastern China. The total mixing ratios of 15 kinds of gaseous carbonyls (Σ15OVOCs) was 12.15 ± 2.53 ppbv in Fujian Province. The concentrations in the eastern coastal regions were higher than those in the western mountainous regions. Formaldehyde, acetone, and acetaldehyde were the top three species of Σ15OVOCs concentration. Photochemical formation during the daytime and vehicle emission during the rush hours significantly contributed to formaldehyde and acetaldehyde. The shoe-making industry is well developed in Putian, where the acetone mixing ratio was significantly higher than in other cities. The O3-NOX-VOCs sensitivities at all urban sites were in VOC-limited or transitional regimes based on the ratios of formaldehyde to NO2; from morning to afternoon, the VOC-limited sensitivity decreased, and the NOX-limited sensitivity increased gradually. Formaldehyde contributed the most significant O3 formation potential (OFP) proportion of the Σ15OVOCs. The OFP of carbonyl species accounted for half of the total VOCs in Fuzhou and Putian, suggesting that more attention needs to be given to gaseous carbonyls control. Overall, the links inferred by this study provide evidence and clues to mitigate the increasing ambient O3 concentration on the west coast of the Taiwan Strait.
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Affiliation(s)
- Xin Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Zhenhai Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Zhen He
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; State Key Laboratory of Coal Resources and Safe Mining, College of Geoscience and Surveying Engineering, China University of Mining and Technology, Beijing 100083, China
| | - Xuefen Zhong
- Fujian Academy of Environmental Sciences, Fuzhou 350013, China
| | - Fang Bi
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yunfeng Li
- School of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China
| | - Rui Gao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Hong Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Wenxing Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Environment Research Institute, Shandong University, Qingdao 266237, China
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13
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Chen L, Huang Y, Xue Y, Jia Z, Wang W. Kinetic and Mechanistic Investigations of OH-Initiated Atmospheric Degradation of Methyl Butyl Ketone. J Phys Chem A 2022; 126:2976-2988. [PMID: 35536543 DOI: 10.1021/acs.jpca.2c01126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Methyl butyl ketone (MBK, 2-hexanone) is a common atmospheric oxygenated volatile organic compound (OVOC) owing to broad industrial applications, but its atmospheric oxidation mechanism remains poorly understood. Herein, the detailed mechanisms and kinetic properties of MBK oxidation initiated by OH radicals and subsequent transformation of the resulting intermediates are performed by employing quantum chemical and kinetic modeling methods. The calculations show that H-abstraction at the C4 position of MBK is more favorable than those at the other positions, with the total rate coefficient of k(T) = 4.13 × 10-14 exp(1576/T) cm3 molecule-1 s-1 at 273-400 K. The dominant pathway of unimolecular degradation of the C-centered alkyl radical is 1,2-acyl group migration. For the isomerization of the peroxy radical RO2, 1,5- and 1,6-H shifts are more favorable than 1,3- and 1,4-H shifts. The multiconformer rate coefficient kMC-TST of the first H-shift of the RO2 radical is estimated to be 1.40 × 10-3 s-1 at room temperature. Compared to the H-shifts of analogous aliphatic RO2 radicals, it can be concluded that the carbonyl group enhances the H-shift rates by as much as 2-4 orders of magnitude. The rate coefficients of the RO2 radical reaction with the HO2 radical exhibit a weakly negative temperature dependence, and the pseudo-first-order rate constant k'HO2 = kHO2[HO2] is calculated to be 3.32-22.10 × 10-3 s-1 at ambient temperature. The bimolecular reaction of the RO2 radical with NO leads to the formation of 3-oxo-butanal as the main product with the formation concentration of 2.2-7.4 μg/m3 in urban areas. The predicted pseudo-first-order rate constant k'NO = kNO[NO] is 2.20-9.98 s-1 at room temperature. By comparing the kMC-TST, k'HO2, and k'NO, it can be concluded that reaction with NO is the dominant removal pathway for the RO2 radical formed from the OH-initiated oxidation of MBK. These findings are expected to deepen our understanding of the photochemical oxidation of ketones under realistic atmospheric conditions.
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Affiliation(s)
- Long Chen
- State Key Lab of Loess and Quaternary Geology (SKLLQG), Institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi'an 710061, China.,CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China
| | - Yu Huang
- State Key Lab of Loess and Quaternary Geology (SKLLQG), Institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi'an 710061, China.,CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China
| | - Yonggang Xue
- State Key Lab of Loess and Quaternary Geology (SKLLQG), Institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi'an 710061, China.,CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China
| | - Zhihui Jia
- School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Wenliang Wang
- School of Chemistry and Chemical Engineering, Key Laboratory for Macromolecular Science of Shaanxi Province, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
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14
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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.
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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
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15
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Dong P, Chen Z, Qin X, Gong Y. Water Significantly Changes the Ring-Cleavage Process During Aqueous Photooxidation of Toluene. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:16316-16325. [PMID: 34877862 DOI: 10.1021/acs.est.1c04770] [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: 06/13/2023]
Abstract
As a major constituent of aromatic compounds, toluene exists widely in environmental aqueous phases. This research investigated the aqueous-phase OH oxidation of toluene to determine how liquid water changes the radical chemistry of ring-cleavage pathways. Results show that ring-cleavage pathways through the C7 bicyclic peroxy radical (BPR) account for about 70% of total aqueous-phase oxidation pathways, which is similar to that in the gas-phase oxidation. However, detailed ring-cleavage pathways in the aqueous phase change significantly compared with those in the gas phase as shown by the decreased production of glyoxal and methylglyoxal and the enhanced production of formic acid and acetic acid as primary products, which can be attributed to the presence of liquid water. Water facilitates the formation of the BPR whose structure is different from that in the gas-phase oxidation and results in different ring-cleavage pathways through hydrogen-shift reactions. Furthermore, water helps the hydration of acyl radicals formed by the BPR to produce organic acids. With the suggested ring-cleavage mechanisms, a box model can simulate aqueous-phase product distributions better than that with the classical ring-cleavage mechanisms. Given the influence of water on reaction mechanisms, aqueous-phase oxidation of hydrophobic organic compounds may be more important than previously assumed.
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Affiliation(s)
- Ping Dong
- State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Zhongming Chen
- State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xuan Qin
- State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yiwei Gong
- State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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16
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Prasad VK, Khalilian MH, Otero-de-la-Roza A, DiLabio GA. BSE49, a diverse, high-quality benchmark dataset of separation energies of chemical bonds. Sci Data 2021; 8:300. [PMID: 34815431 PMCID: PMC8611007 DOI: 10.1038/s41597-021-01088-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 11/01/2021] [Indexed: 01/23/2023] Open
Abstract
We present an extensive and diverse dataset of bond separation energies associated with the homolytic cleavage of covalently bonded molecules (A-B) into their corresponding radical fragments (A. and B.). Our dataset contains two different classifications of model structures referred to as "Existing" (molecules with associated experimental data) and "Hypothetical" (molecules with no associated experimental data). In total, the dataset consists of 4502 datapoints (1969 datapoints from the Existing and 2533 datapoints from the Hypothetical classes). The dataset covers 49 unique X-Y type single bonds (except H-H, H-F, and H-Cl), where X and Y are H, B, C, N, O, F, Si, P, S, and Cl atoms. All the reference data was calculated at the (RO)CBS-QB3 level of theory. The reference bond separation energies are non-relativistic ground-state energy differences and contain no zero-point energy corrections. This new dataset of bond separation energies (BSE49) is presented as a high-quality reference dataset for assessing and developing computational chemistry methods.
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Affiliation(s)
- Viki Kumar Prasad
- Department of Chemistry, University of British Columbia, Kelowna, British Columbia, V1V 1V7, Canada
| | - M Hossein Khalilian
- Department of Chemistry, University of British Columbia, Kelowna, British Columbia, V1V 1V7, Canada
| | - Alberto Otero-de-la-Roza
- Departamento de Química Física y Analítica, Facultad de Química, Universidad de Oviedo, MALTA Consolider Team, E-33006, Oviedo, Spain
| | - Gino A DiLabio
- Department of Chemistry, University of British Columbia, Kelowna, British Columbia, V1V 1V7, Canada.
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17
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Zhang R, Gen M, Fu TM, Chan CK. Production of Formate via Oxidation of Glyoxal Promoted by Particulate Nitrate Photolysis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:5711-5720. [PMID: 33861585 DOI: 10.1021/acs.est.0c08199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Particulate nitrate photolysis can produce oxidants (i.e., OH, NO2, and NO2-/HNO2) in aqueous droplets and may play a potential role in increased atmospheric oxidative capacity. Our earlier works have reported on the SO2 oxidation promoted by nitrate photolysis to produce sulfate. Here, we used glyoxal as a model precursor to examine the role of particulate nitrate photolysis in the formation of secondary organic aerosol (SOA) from particle-phase oxidation of glyoxal by OH radicals. Particles containing sodium nitrate and glyoxal were irradiated at 300 nm. Interestingly, typical oxidation products of oxalic acid, glyoxylic acid, and higher-molecular-weight products reported in the literature were not found in the photooxidation process of glyoxal during nitrate photolysis in the particle phase. Instead, formic acid/formate production was found as the main oxidation product. At glyoxal concentration higher than 3 M, we found that the formic acid/formate production rate increases significantly with increasing glyoxal concentration. Such results suggest that oxidation of glyoxal at high concentrations by OH radicals produced from nitrate photolysis in aqueous particles may not contribute significantly to SOA formation since formic acid is a volatile species. Furthermore, recent predictions of formic acid/formate concentration from the most advanced chemical models are lower than ambient observations at both the ground level and high altitude. The present study reveals a new insight into the production of formic acid/formate as well as a sink of glyoxal in the atmosphere, which may partially narrow the gap between model predictions and field measurements in both species.
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Affiliation(s)
- Ruifeng Zhang
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Masao Gen
- Faculty of Frontier Engineering, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Tzung-May Fu
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chak K Chan
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
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18
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Ma F, Guo X, Xia D, Xie HB, Wang Y, Elm J, Chen J, Niu J. Atmospheric Chemistry of Allylic Radicals from Isoprene: A Successive Cyclization-Driven Autoxidation Mechanism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:4399-4409. [PMID: 33769798 DOI: 10.1021/acs.est.0c07925] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The atmospheric chemistry of isoprene has broad implications for regional air quality and the global climate. Allylic radicals, taking 13-17% yield in the isoprene oxidation by •Cl, can contribute as much as 3.6-4.9% to all possible formed intermediates in local regions at daytime. Considering the large quantity of isoprene emission, the chemistry of the allylic radicals is therefore highly desirable. Here, we investigated the atmospheric oxidation mechanism of the allylic radicals using quantum chemical calculations and kinetics modeling. The results indicate that the allylic radicals can barrierlessly combine with O2 to form peroxy radicals (RO2•). Under ≤100 ppt NO and ≤50 ppt HO2• conditions, the formed RO2• mainly undergo two times "successive cyclization and O2 addition" to finally form the product fragments 2-alkoxy-acetaldehyde (C2H3O2•) and 3-hydroperoxy-2-oxopropanal (C3H4O4). The presented reaction illustrates a novel successive cyclization-driven autoxidation mechanism. The formed 3-hydroperoxy-2-oxopropanal product is a new isomer of the atmospheric C3H4O4 family and a potential aqueous-phase secondary organic aerosol precursor. Under >100 ppt NO condition, NO can mediate the cyclization-driven autoxidation process to form C5H7NO3, C5H7NO7, and alkoxy radical-related products. The proposed novel autoxidation mechanism advances our current understanding of the atmospheric chemistry of both isoprene and RO2•.
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Affiliation(s)
- Fangfang Ma
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Dalian University of Technology, Dalian 116024, China
- Department of Atmospheric Sciences, Texas A&M University, College Station, Texas 77843, United States
| | - Xirui Guo
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Dalian University of Technology, Dalian 116024, China
| | - Deming Xia
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Dalian University of Technology, Dalian 116024, China
| | - Hong-Bin Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Dalian University of Technology, Dalian 116024, China
| | - Yonghong Wang
- Institute for Atmospheric and Earth System Research, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Jonas Elm
- Department of Chemistry and iClimate, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Dalian University of Technology, Dalian 116024, China
| | - Junfeng Niu
- Research Center for Eco-Environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
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19
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Wang J, Ye J, Zhang Q, Zhao J, Wu Y, Li J, Liu D, Li W, Zhang Y, Wu C, Xie C, Qin Y, Lei Y, Huang X, Guo J, Liu P, Fu P, Li Y, Lee HC, Choi H, Zhang J, Liao H, Chen M, Sun Y, Ge X, Martin ST, Jacob DJ. Aqueous production of secondary organic aerosol from fossil-fuel emissions in winter Beijing haze. Proc Natl Acad Sci U S A 2021; 118:e2022179118. [PMID: 33593919 PMCID: PMC7923588 DOI: 10.1073/pnas.2022179118] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Secondary organic aerosol (SOA) produced by atmospheric oxidation of primary emitted precursors is a major contributor to fine particulate matter (PM2.5) air pollution worldwide. Observations during winter haze pollution episodes in urban China show that most of this SOA originates from fossil-fuel combustion but the chemical mechanisms involved are unclear. Here we report field observations in a Beijing winter haze event that reveal fast aqueous-phase conversion of fossil-fuel primary organic aerosol (POA) to SOA at high relative humidity. Analyses of aerosol mass spectra and elemental ratios indicate that ring-breaking oxidation of POA aromatic species, leading to functionalization as carbonyls and carboxylic acids, may serve as the dominant mechanism for this SOA formation. A POA origin for SOA could explain why SOA has been decreasing over the 2013-2018 period in response to POA emission controls even as emissions of volatile organic compounds (VOCs) have remained flat.
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Affiliation(s)
- Junfeng Wang
- 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, Nanjing 210044, China
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138
| | - Jianhuai Ye
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138
| | - Qi Zhang
- Department of Environmental Toxicology, University of California, Davis, CA 95616
| | - Jian Zhao
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Yangzhou Wu
- Department of Atmospheric Sciences, School of Earth Sciences, Zhejiang University, Hangzhou 310027, China
| | - Jingyi Li
- 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, Nanjing 210044, China
| | - Dantong Liu
- Department of Atmospheric Sciences, School of Earth Sciences, Zhejiang University, Hangzhou 310027, China
| | - Weijun Li
- Department of Atmospheric Sciences, School of Earth Sciences, Zhejiang University, Hangzhou 310027, China
| | - Yange Zhang
- Institute of Oceanography, Minjiang University, Fuzhou 350108, China
| | - Cheng Wu
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, China
| | - Conghui Xie
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Yiming Qin
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138
| | - Yali Lei
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138
| | - Xiangpeng Huang
- 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, Nanjing 210044, China
| | - Jianping Guo
- State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China
| | - Pengfei Liu
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332
| | - Pingqing Fu
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China
| | - Yongjie Li
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau 999078, China
| | - Hyun Chul Lee
- Samsung Advance Institute of Technology, Gyeonggi-do, Suwon-si 16678, Republic of Korea
| | - Hyoungwoo Choi
- Samsung Advance Institute of Technology, Gyeonggi-do, Suwon-si 16678, Republic of Korea
| | - Jie Zhang
- Department of Atmospheric Science, Colorado State University, Fort Collins, CO 80523
| | - Hong Liao
- 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, Nanjing 210044, China
| | - Mindong Chen
- 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, Nanjing 210044, China
| | - Yele Sun
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, 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, Nanjing 210044, China;
| | - Scot T Martin
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138
| | - Daniel J Jacob
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138;
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20
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Ubiquitous atmospheric production of organic acids mediated by cloud droplets. Nature 2021; 593:233-237. [PMID: 33981052 PMCID: PMC8116209 DOI: 10.1038/s41586-021-03462-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 03/17/2021] [Indexed: 02/03/2023]
Abstract
Atmospheric acidity is increasingly determined by carbon dioxide and organic acids1-3. Among the latter, formic acid facilitates the nucleation of cloud droplets4 and contributes to the acidity of clouds and rainwater1,5. At present, chemistry-climate models greatly underestimate the atmospheric burden of formic acid, because key processes related to its sources and sinks remain poorly understood2,6-9. Here we present atmospheric chamber experiments that show that formaldehyde is efficiently converted to gaseous formic acid via a multiphase pathway that involves its hydrated form, methanediol. In warm cloud droplets, methanediol undergoes fast outgassing but slow dehydration. Using a chemistry-climate model, we estimate that the gas-phase oxidation of methanediol produces up to four times more formic acid than all other known chemical sources combined. Our findings reconcile model predictions and measurements of formic acid abundance. The additional formic acid burden increases atmospheric acidity by reducing the pH of clouds and rainwater by up to 0.3. The diol mechanism presented here probably applies to other aldehydes and may help to explain the high atmospheric levels of other organic acids that affect aerosol growth and cloud evolution.
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21
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Song M, Liu Y, Li X, Lu S. Advances on Atmospheric Oxidation Mechanism of Typical Aromatic Hydrocarbons. ACTA CHIMICA SINICA 2021. [DOI: 10.6023/a21050224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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22
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Xu L, Møller KH, Crounse JD, Kjaergaard HG, Wennberg PO. New Insights into the Radical Chemistry and Product Distribution in the OH-Initiated Oxidation of Benzene. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13467-13477. [PMID: 33084314 DOI: 10.1021/acs.est.0c04780] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Emissions of aromatic compounds cause air pollution and detrimental health effects. Here, we explore the reaction kinetics and products of key radicals in benzene photo-oxidation. After initial OH addition and reaction with O2, the effective production rates of phenol and bicyclic peroxy radical (BCP-peroxy) are experimentally constrained at 295 K to be 420 ± 80 and 370 ± 70 s-1, respectively. These rates lead to approximately 53% yield for phenol and 47% yield for BCP-peroxy under atmospheric conditions. The reaction of BCP-peroxy with NO produces bicyclic hydroxy nitrate with a branching ratio <0.2%, indicating efficient NOx recycling. Similarly, the reaction of BCP-peroxy with HO2 largely recycles HOx, producing the corresponding bicyclic alkoxy radical (BCP-oxy). Because of the presence of C-C double bonds and multiple functional groups, the chemistry of BCP-oxy and other alkoxy radicals in the system is diverse. Experimental results suggest the aldehydic H-shift and ring-closure to produce an epoxide functionality could be competitive with classic decomposition of alkoxy radicals. These reactions are potential sources of highly oxygenated molecules. Finally, despite the large number of compounds observed in our study, we are unable to account for ∼20% of the carbon flow.
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Affiliation(s)
- Lu Xu
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, United States
| | - Kristian H Møller
- Department of Chemistry, University of Copenhagen, Universitetsparken5, DK-2100 Copenhagen Ø, Denmark
| | - John D Crounse
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, United States
| | - Henrik G Kjaergaard
- Department of Chemistry, University of Copenhagen, Universitetsparken5, DK-2100 Copenhagen Ø, Denmark
| | - Paul O Wennberg
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, United States
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125, United States
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