TY - BOOK

T1 - Atmospheric Gas-Phase Reactions of Fluorinated Compounds and Alkenes

AU - Østerstrøm, Freja From

PY - 2016

Y1 - 2016

N2 - Experimental studies have been performed using three different smog chamber setups to investigate the atmospheric chemistry of fluorinated compounds as well as alkenes. The three instruments were at Ford Motor Company, USA, National Center for Atmospheric Research, USA, and Copenhagen Center for Atmospheric Research, Denmark. All setups consist of a chamber and uses UV light to initiate the experiments and Fourier transform infrared spectroscopy for the analysis of the data.The atmospheric chemistry of new chlorofluorocarbon replacements is discussed. Experimental studies have been performed on: (CF3)2CHOCH3, (CF3)2CHOCHO, CF3C(0)OCH3, Z- and E-CF 3CH=CHCF3. These studies include determining the kinetics of the reactions of the compounds with atmospheric oxidants, the products of the reactions, and assessing the atmospheric impact of the compounds by estimating their atmospheric lifetime and global warming potential.A mechanistic study of the hydrofluorocarbon CH2F2 has been performed in the absence and presence of hydrocarbons, investigating the possibility of formation of fluorinated alcohols. The reaction mechanism was studied in detail, examining competition between peroxy and alkoxy radical reactions. As part of this, the atmospheric fates of the alkoxy radical CHF2O and the alcohol CHF2OH were determined.The reactions of several C3-C6 alkenes and one unsaturated C5 alcohol with NO3 radicals were studied, determining general reaction trends and the products formed in the reactions. The products formed in the reaction of NO3 radicals with trans-2-butene were quantified, and the fate of the nitrooxy alkoxy radical CH3CH(0•)CH(ONO2)CH3 was determined. The observed products were compared to the predictions used in global atmospheric chemistry models.

AB - Experimental studies have been performed using three different smog chamber setups to investigate the atmospheric chemistry of fluorinated compounds as well as alkenes. The three instruments were at Ford Motor Company, USA, National Center for Atmospheric Research, USA, and Copenhagen Center for Atmospheric Research, Denmark. All setups consist of a chamber and uses UV light to initiate the experiments and Fourier transform infrared spectroscopy for the analysis of the data.The atmospheric chemistry of new chlorofluorocarbon replacements is discussed. Experimental studies have been performed on: (CF3)2CHOCH3, (CF3)2CHOCHO, CF3C(0)OCH3, Z- and E-CF 3CH=CHCF3. These studies include determining the kinetics of the reactions of the compounds with atmospheric oxidants, the products of the reactions, and assessing the atmospheric impact of the compounds by estimating their atmospheric lifetime and global warming potential.A mechanistic study of the hydrofluorocarbon CH2F2 has been performed in the absence and presence of hydrocarbons, investigating the possibility of formation of fluorinated alcohols. The reaction mechanism was studied in detail, examining competition between peroxy and alkoxy radical reactions. As part of this, the atmospheric fates of the alkoxy radical CHF2O and the alcohol CHF2OH were determined.The reactions of several C3-C6 alkenes and one unsaturated C5 alcohol with NO3 radicals were studied, determining general reaction trends and the products formed in the reactions. The products formed in the reaction of NO3 radicals with trans-2-butene were quantified, and the fate of the nitrooxy alkoxy radical CH3CH(0•)CH(ONO2)CH3 was determined. The observed products were compared to the predictions used in global atmospheric chemistry models.

UR - https://soeg.kb.dk/permalink/45KBDK_KGL/fbp0ps/alma99122581985905763

M3 - Ph.D. thesis

BT - Atmospheric Gas-Phase Reactions of Fluorinated Compounds and Alkenes

PB - Department of Chemistry, Faculty of Science, University of Copenhagen

ER -