Atmospheric Chemistry of Tetrahydrofuran, 2-Methyltetrahydrofuran, and 2,5-Dimethyltetrahydrofuran: Kinetics of Reactions with Chlorine Atoms, OD Radicals, and Ozone

作者：Andersen Christina; Nielsen Ole John; Osterstrom Freja F; Ausmeel Stina; Nilsson Elna J K; Andersen Mads P Sulbaek^*

来源：Journal of Physical Chemistry A, 2016, 120(37): 7320-7326.

DOI：10.1021/acs.jpca.6b06618

FTIR smog chamber techniques were used to study the kinetics of the gas-phase reactions of Cl atoms, OD radicals, and O-3 with the five-membered ring-structured compounds tetrahydrofuran (C4H8O, THF), 2-methyltetrahydrofuran (CH3C4H7O, 2-MTHF), 2,5-dimethyltetrahydrofuran ((CH3)(2)C4H5O, 2,5-DMTHF), and furan (C4H4O). The rate coefficients determined using relative rate methods were k(THF+Cl) = (1.96 +/- 0.24) x 10(-10), k(THF+OD) = (1.81 +/- 0.27) x 10(-11), k(THF+O3) = (6.41 +/- 2.90) x 10(-21), k(2-MTHF+Cl) = (2.65 +/- 0.43) x 10(-10), k(2-MTHF+OD) = (2.41 +/- 0.51) x 10(-11), k2-MTHF+O3 = (1.87 +/- 0.82) x 10-20, k2,5-DMTHF+OD = (4.56 +/- 0.68) x 10-11, k(2,5-DMTHF+Cl) = (2.84 +/- 0.34) x 10-10, k(2,5-DMTHF+O3) = (4.58 +/- 2.18), kfuran+Cl = (2.39 +/- 0.27) x 10(-10), and kfuran+O3 = (2.60 +/- 0.31) x 10(-18) molecules cm3 s1. Rate coefficients of the reactions with ozone were also determined using the absolute rate method under pseudo-first-order conditions. OD radicals, in place of OH radicals, were produced from CD3ONO to avoid spectral overlap of isopropyl and methyl nitrite with the reactants. The kinetics of OD radical reactions are expected to resemble the kinetics of OH radical reactions, and the rate coefficients of the reactions with OD radicals were used to calculate the atmospheric lifetimes with respect to reactions with OH radicals. The lifetimes of THF, 2-MTHF, and 2,5-DMTHF are approximately 15, 12, and 6 h, respectively.

• 出版日期2016-9-22