DOI: 10.1016/j.atmosenv.2014.01.060
Scopus记录号: 2-s2.0-84894070939
论文题名: Gas-phase reactivity study of a series of hydrofluoroolefins (HFOs) toward OH radicals and Cl atoms at atmospheric pressure and 298K
作者: Tovar C ; M ; , Blanco M ; B ; , Barnes I ; , Wiesen P ; , Teruel M ; A
刊名: Atmospheric Environment
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2014
卷: 88 起始页码: 107
结束页码: 114
语种: 英语
英文关键词: (E/Z)-1,2,3,3,3-pentafluoropropene
; 2-Fluoropropene
; 3,3,3-Trifluoro-2-(trifluoromethyl)propene
; CFCs replacements
; Cis effect
Scopus学科分类: Environmental Science: Water Science and Technology
; Earth and Planetary Sciences: Earth-Surface Processes
; Environmental Science: Environmental Chemistry
英文摘要: In order to assess the environmental impact of possible candidates such as hydrofluoroolefins to replace the CFCs in the industry, it is necessary to perform kinetic and product studies of their degradation in the air initiated by the main tropospheric oxidants. In this sense, the relative-rate technique has been used to determine rate coefficients for the reactions of 2-fluoropropene (CH3CFCH2); 3,3,3-trifluoro-2-(trifluoromethyl)propene ((CF3)2CCH2) and (E/Z)-1,2,3,3,3-pentafluoropropene ((E/Z)-CF3CFCHF) with OH radicals and Cl atoms at (298±3) K and (760±10) Torr total pressure of synthetic air using different reference compounds.The experiments were performed in an environmental chamber with "in situ" FTIR spectroscopy tomonitorthe concentration-time profiles of the reactants. The following room temperature rate coefficients(incm3molecule-1s-1) were obtained: k1(OH+CH3CFCH2)=(1.55±0.39)×10-11, k2(OH+(CF3)2CCH2)=(6.58±2.25)×10-13, k3 (OH+((E/Z)-CF3CFCHF); 93% E isomer)=(2.62±0.76)×10-12,k4 (Cl+CH3CFCH2)=(1.64±0.26)×10-10, k5 (Cl+(CF3)2CCH2)=(3.50±0.85)×10-11 and k6 (Cl+((E/Z)-CF3CFCHF); 93% E isomer)=(4.52±0.98)×10-11. To the best of our knowledge this work provides the first kinetic study for the reactions of CH3CFCH2 and (CF3)2CCH2 with OH radicals and Cl atoms.Free-energy relationships are presented, and the effect of F atom and CF3 group substitution in the hydrofluoroolefins is discussed in terms of reactivity toward both OH radicals and Cl atoms.On the basis of the kinetic measurements, tropospheric lifetimes of CH3CFCH2, (CF3)2CCH2 and (E/Z)-CF3CFCHF will primarily be determined by their reaction with hydroxyl radicals with estimated lifetimes of approximately 1, 18 and 4 days, respectively. For the reactions of the fluoroalkenes with chlorine atoms the corresponding values of the lifetimes are 14, 66 and 51, respectively. © 2014 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/80686
Appears in Collections: 气候变化事实与影响
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作者单位: INFIQC (CONICET- Facultad de Ciencias Químicas, Universidad Nacional de Córdoba). Dpto. de Fisicoquímica, Ciudad Universitaria, 5000 Córdoba, Argentina; Physikalische Chemie/FB-C, Bergische Universität Wuppertal, Wuppertal, Germany
Recommended Citation:
Tovar C,M,, Blanco M,et al. Gas-phase reactivity study of a series of hydrofluoroolefins (HFOs) toward OH radicals and Cl atoms at atmospheric pressure and 298K[J]. Atmospheric Environment,2014-01-01,88