Renzhang Liu

The gas phase reactions of hydroxyl radicals with a series of nitroalkanes over the temperature range 240–400 K

Abstract Absolute rate constants were determined for the gas phase reactions of OH radicals with a series of nitroalkanes by the flash photolysis-resonance fluorescence technique. Experiments were performed at total pressures from 25 to 50 Torr using Ar as a diluent gas. Experiments with nitromethane and nitromethane-d3 at 296 K yielded rate constants of (1.58±0.09) × 10−14 and (0.9±0.04) × 10−14 cm3 molecule−1 s−1, respectively. Data from experiments over the temperature range 240–400 K for nitroethane, 1-nitropropane, 2-nitropropane, 1-nitrobutane, and 1-nitropentane were used to evaluate their Arrhenius parameters. The results are discussed in terms of the reaction mechanism, and are compared to previous literature data.

Rate constants for the gas phase reactions of the OH radical with CF3CF2CHCl2 (HCFC-225ca) and CF2ClCF2CHClF (HCFC-225cb)

Rate constants have been measured for the gas phase reactions of the hydroxyl radical (OH) with the hydrochlorofluorocarbons CF3CF2CHCl2 (HCFC-225ca) over the temperature range 270 to 400 K and CF2ClCF2CHClF (HCFC-225cb) over the temperature range 298 to 400 K. The Arrhenius expressions k(225ca) = (1.92 ± 0.52) × 10−12 exp(−1290 ± 90/T) cm3 molecule−1 s−1 and k(225cb) = (6.75 ± 3.70) × 10−13 exp(−1300 ± 180/T) cm3 molecule−1 s−1 were derived from the kinetic data.