924-43-6Relevant articles and documents
Rate constants for the decomposition of 2-butoxy radicals and their reaction with NO and O2
Falgayrac,Caralp,Sokolowski-Gomez,Devolder,Fittschen
, p. 4127 - 4132 (2004)
The reactivity of 2-butoxy radicals has been investigated using the laser photolysis/laser induced fluorescence technique. Three reactions have been studied: (i) The rate constants for the reaction with NO have been measured by the same technique at total pressures between 0.03 1 = (4.4 ± 0.6) × 10-12 exp((4.9 ± 0.3) kJ mol -1/RT) cm3 s-1. (ii) The rate constant with O2 has been measured at room temperature and 0.131 bar of helium: k2 = (9 ± 2) × 10-15 cm3 s -1. Significant quenching of 2-butoxy fluorescence by O2 prevented experiments in a larger temperature range: kq,O2 = (4 ± 1) × 10-11 cm3 s-1. (iii) The temperature and pressure dependence of the unimolecular decomposition at total pressures between 0.01 cent have been extracted from a falloff analysis of the experimental results: k3,0,He = 3.2 × 10 -8 exp(-35.9 kJ mol-1/RT) cm3 s-1, k3,∞ = 1.1 × 1014 exp(-53.6 kJ mol -1/RT) s-1, and F3.c = 0.87 - T/870 K. We anticipate an uncertainty of ±30% for these rate constants. These results are in excellent agreement with earlier predictions (C. Fittschen, H. Hippler and B. Viskolcz, Phys. Chem. Chem. Phys., 2000, 2, 1677-1683 (ref. 1); R. Mereau, M.-T. Rayez, F. Caralp and J.-C. Rayez, Phys. Chem. Chem. Phys., 2000, 2, 3765 (ref. 2)).
Spectrokinetic study of the reaction system of 2NO2?N 2O4 with butanols between 320-358 K in the gas phase
Wojcik-Pastuszka,Jodkowski
experimental part, p. 131 - 143 (2009/09/25)
Spectrokinetic studies of the gas-phase equilibrium between nitrogen tetroxide and butanols in the reaction system 2NO2?N 2O4 (1,2), N2O4+ROH? RONO+HNO3 (3,4) have been undertaken in the temperature range 298-358 K. The products - RONO (n-butyl-ONO, sec-butyl-ONO, iso-butyl-ONO and tert-butyl-ONO) - were identified by their UV spectra and the values of the maxima UV absorption cross sections were determined in the range 320-420 nm at 298 K. The temperature dependences of both the forward and reverse rate constants, k3 and k4, were obtained. The extrapolated values of the forward rate constants are 10-18 k3 av/cm3 molec-1 s-1 3.9±1.0; 1.7±0.3; 4.2±0.8; 5.7±1.1 and the reverse rate constants are 10-20 k4av/cm3 molec -1 s-1 0.3±0.1; 2.3±0.6; 0.4±0.1; 2.3±0.6 at 298 K for the reaction of NO2/N2O 4 with n-butanol, sec-butanol, iso-butanol and tert-butanol, respectively. The activation energy for the forward E3 and for the reverse E4 reaction were derived.
Atmospheric fate of alkoxy radicals: Branching ratio of evolution pathways for 1-propoxy, 2-propoxy, 2-butoxy and 3-pentoxy radicals
Meunier,Doussin,Chevallier,Durand-Jolibois,Picquet-Varrault,Carlier
, p. 4834 - 4839 (2007/10/03)
As the last step of VOC oxidation in the atmosphere, the evolution of alkoxy radicals determines the nature and the concentration of the secondary compounds formed. Branching ratios between decomposition and reaction with O2 of 1-propoxy, 2-propoxy, 2-butoxy, and 3-pentoxy radicals were measured at room temperature and 1 atm in a simulation chamber using FTIR spectroscopy as an analytical device. The ratio varied depending on the leaving alkyl group and the class of alkoxy. No additional decomposition due to excited radicals was observed. The results could be used directly for tropospheric simulation purposes. Formaldehyde might be a photolytic source of HOx through the production of H and HCO radicals and acetaldehyde is the key precursor of the toxic NOx reservoir, peroxy-acetyl nitrate. In the lower troposphere, 1-propoxy and 2-propoxy radicals react mainly with O2 while decomposition is an important reaction pathway for 2-butoxy and 3-pentoxy. Consequently, C1 and C2 aldehyde production from the two longer chain alkoxys will occur very close to the area of initial VOC oxidation, while for the alkoxys exhibiting a minor decomposition pathway, the formaldehyde or acetaldehyde production will take place after oxidation of all the intermediate secondary compounds, far from the emission area of the primary compound.
