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The rate coefficient for the gas phase reaction of the OH radical with 1,2-propylene oxide (PPO) has been measured at 298 K using a relative rate method, employing Gas Chromatography (GC) technique, using ethane and 1,2-dichloroethane as reference compounds. Temperature dependence of the above reaction is also studied using an absolute rate method, employing Laser Photolysis-Laser Induced Fluorescence (LP-LIF) technique, over a range of 261–335 K. The measured bimolecular rate coefficients were fitted into the Arrhenius plot, which yielded a straight line roughly parallel to the x-axis and implies no or very weak temperature dependence. Within the experimental error limits, rate coefficients obtained at various temperatures, are found to vary within a narrow range from (4.65 ± 0.24) × 10−13 to (4.80 ± 0.24) × 10−13 cm3 molecule−1 s−1. Room temperature rate coefficient of the reaction of PPO with the OH radical was found to be (4.65 ± 0.24) × 10−13 cm3 molecule−1 s−1, using LP-LIF technique. These results have been discussed with available literature to unveil the probable mechanism. An average tropospheric lifetime of PPO has been estimated to be about two weeks for degradation by the OH radical. In addition, atmospheric parameters such as Radiative Efficiency (RE) and Global Warming Potential (GWP) for PPO are determined. Stable products formed are characterized using GC-MS and FT-IR techniques. Theoretical calculations are performed to understand the energetics and mechanism of H atom abstraction by OH, and also to complement the experimental observations.

The rate coefficients for the reactions of OH radicals with three fluoroalcohols, CF 3 CH 2 OH ( k 1 ), CF 3 CF 2 CF 2 CH 2 OH ( k 2 ), and CHF 2 CF 2 CH 2 OH ( k 3 ), have been measured in the temperature range of 298–363 K, at a total pressure of ∼55 torr, using LP-LIF method. The kinetic parameters measured for CF 3 CH 2 OH, which is well studied, matches with the previous reports within error limits. The rate expression for k 2 is (1.54 ± 0.80) × 10 −12 exp (−765 ± 170)/ T ), and for k 3 is (1.12 ± 0.26) × 10 −12 exp (−560 ± 80)/ T ). Based on the above values of the rate coefficients, the tropospheric lifetimes with respect to removal by reaction with OH have been estimated to be 0.38 and 0.26 years for CF 3 CF 2 CF 2 CH 2 OH and CHF 2 CF 2 CH 2 OH respectively, supporting their potential use as HFC alternatives. The results are discussed along with the literature data on other fluoroalcohols. The present study is aimed to assess the effect of additional CF 2 groups and H atoms on tropospheric lifetime and global warming potential of fluoroalcohols. The results confirm that the rate coefficients at room temperature and activation energy parameters are independent of n, for the reaction of OH with fluoroalcohols of general formula CF 3 (CF 2 ) n CH 2 OH, which are potential CFC/HFC alternatives.