| Title: | OH-Initiated Oxidation of Acetylacetone: Implications for Ozone and Secondary Organic Aerosol Formation |
| Author(s): | Ji Y; Zheng J; Qin D; Li Y; Gao Y; Yao M; Chen X; Li G; An T; Zhang R; |
| Address: | "Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control , Guangdong University of Technology , Guangzhou 510006 , P. R. China. Collaborative Innovation Center of Atmospheric Environment and Equipment Technology , Nanjing University of Information Science & Technology , Nanjing 210044 , P. R. China. Department of Atmospheric Sciences and Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "Acetylacetone (AcAc) is a common atmospheric oxygenated volatile organic compound due to broad industrial applications, but its atmospheric oxidation mechanism is not fully understood. We investigate the mechanism, kinetics, and atmospheric fate of the OH-initiated oxidation for the enolic and ketonic isomers of AcAc using quantum chemical and kinetic rate calculations. OH addition to enol-AcAc is more favorable than addition to keto-AcAc, with the total rate constant of 1.69 x 10(-13) exp(1935/T) cm(3) molecule(-1) s(-1) over the temperature range of 200-310 K. For the reaction of the enol-AcAc with OH, the activation energies of H-abstraction are at least 4 kcal mol(-1) higher than those of OH-addition, and the rate constants for OH-addition are by 2-3 orders of magnitude higher than those for H-abstraction. Oxidation of AcAc is predicted to yield significant amounts of acetic acid and methylglyoxal, larger than those are currently recognized. A lifetime of less than a few hours for AcAc is estimated throughout the tropospheric conditions. In addition, we present field measurements in Beijing and Nanjing, China, showing significant concentrations of AcAc in the two urban locations. Our results reveal that the OH-initiated oxidation of AcAc contributes importantly to ozone and SOA formation under polluted environments" |
| Keywords: | Aerosols Beijing China Hydroxyl Radical Kinetics *Ozone Pentanones; |
| Notes: | "MedlineJi, Yuemeng Zheng, Jun Qin, Dandan Li, Yixin Gao, Yanpeng Yao, Meijing Chen, Xingyu Li, Guiying An, Taicheng Zhang, Renyi eng Research Support, Non-U.S. Gov't 2018/08/31 Environ Sci Technol. 2018 Oct 2; 52(19):11169-11177. doi: 10.1021/acs.est.8b03972. Epub 2018 Sep 11" |
