Atmospheric Chemistry of 1H-Heptafluorocyclopentene (cyc-CF2CF2CF2CF═CH−): Rate Constant, Products, and Mechanism of Gas-Phase Reactions with OH Radicals, IR Absorption Spectrum, Photochemical Ozone Creation Potential, and Global Warming Potential

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• 作者：Dongpeng Liu ; Sheng Qin ; Wei Li ; Di Zhang ; Zhikai Guo
• 刊名：Journal of Physical Chemistry A
• 出版年：2016
• 出版时间：December 8, 2016
• 年：2016
• 卷：120
• 期：48
• 页码：9557-9563
• 全文大小：415K
• ISSN：1520-5215

文摘

The rate constant for gas-phase reactions of OH radicals with 1H-heptafluorocyclopentene (cyc-CF₂CF₂CF₂CF═CH−) was measured using a relative rate method at 298 K: (5.20 ± 0.09) × 10^–14 cm³ molecule^–1 s^–1. The quoted uncertainty includes two standard deviations from the least-squares regression, the systematic error from the GC analysis, and the uncertainties of the rate constants of the reference compounds. The OH-radical-initiated oxidation of cyc-CF₂CF₂CF₂CF═CH– gives the main products COF₂, CO, and CO₂, leading to negligible environmental impact. For consumptions of cyc-CF₂CF₂CF₂CF═CH– of less than 54%, the yield of the formation of ([COF₂] + [CO] + [CO₂])/5 (based on the conservation of carbon) was 0.99 ± 0.02, which is very close to 100%. A possible degradation mechanism was proposed. The radiative efficiency (RE) of cyc-CF₂CF₂CF₂CF═CH– measured at room temperature was 0.215 W m^–2 ppb^–1. The atmospheric lifetime of cyc-CF₂CF₂CF₂CF═CH– was calculated as 0.61 year, and the photochemical ozone creation potential (POCP) was negligible. The 20-, 100-, and 500-year time horizon global warming potentials (GWPs) were estimated as 153, 42, and 12, respectively.