Atmospheric chemistry of C4F9OC2H5 (HFE-7200), C4F9OCH3 (HFE-7100), C3F7OCH3 (HFE-7000) and C3F7CH2OH: temperature dependence of the kinetics of their reactions with OH radicals, atmospheric lifetimes and global warming potentials.
نویسندگان
چکیده
The atmospheric chemistry of several gases used in industrial applications, C(4)F(9)OC(2)H(5) (HFE-7200), C(4)F(9)OCH(3) (HFE-7100), C(3)F(7)OCH(3) (HFE-7000) and C(3)F(7)CH(2)OH, has been studied. The discharge flow technique coupled with mass-spectrometric detection has been used to study the kinetics of their reactions with OH radicals as a function of temperature. The infrared spectra of the compounds have also been measured. The following Arrhenius expressions for the reactions were determined (in units of cm(3) molecule(-1) s(-1)): k(OH + HFE-7200) = (6.9(-1.7)(+2.3)) x 10(-11) exp(-(2030 +/- 190)/T); k(OH + HFE-7100) = (2.8(-1.5)(+3.2)) x 10(-11) exp(-(2200 +/- 490)/T); k(OH + HFE-7000) = (2.0(-0.7)(+1.2)) x 10(-11) exp(-(2130 +/- 290)/T); and k(OH + C(3)F(7)CH(2)OH) = (1.4(-0.2)(+0.3)) x 10(-11) exp(-(1460 +/- 120)/T). From the infrared spectra, radiative forcing efficiencies were determined and compared with earlier estimates in the literature. These were combined with the kinetic data to estimate 100-year time horizon global warming potentials relative to CO(2) of 69, 337, 499 and 36 for HFE-7200, HFE-7100, HFE-7000 and CF(3)CF(2)CF(2)CH(2)OH, respectively.
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ورودعنوان ژورنال:
- Physical chemistry chemical physics : PCCP
دوره 12 19 شماره
صفحات -
تاریخ انتشار 2010