Atmospheric reaction mechanism

One strategy in limiting the formation of ozone and other photochemical oxidants has been the use (in the past) of low reactivity fuels in internal combustion engines. More recently, alternate fuels (methanol, for instance) have been proposed for regions that suffer from elevated levels of photochemical air pollution. The effect of switching to such a low-reactivity fuel may be seen in Equation E2 for methanol, which has a simple atmospheric reaction mechanism. 

Tuazon, E. C., W. P. L. Carter, R. V. Brown, R. Atkinson, A. M. Winer, and J. N. Pitts, Jr., "Atmospheric Reaction Mechanisms of Amine Fuels, Report No. ESL-TR-82-17, U.S. Air Force Engineering and Services Center, Tyndall Air Force Base, FL, March 1982. 

Despite the prevalence of aromatic compounds in the atmosphere, much work is still required to fully elucidate the atmospheric reaction mechanisms of these compounds. Approximately 60-70% of the reacted carbon can be fully accounted for as products (either in the gas or aerosol phases) in aromatic/OH systems [1,16]. 

Carter, W. P. L. Evaluation of a gas-phase atmospheric reaction mechanism for low NOx conditions. Final Report to California Air Resources Board Contract No. 01-305, May 5 (2004a). Available at http //www.certucr.edU/ carter/absts.htm lnoxrptf... 

Carter, W. P. L., and F. W. Lurmann Evaluation of a detailed gas-phase atmospheric reaction mechanism using environmental chamber data. Atmos. Environ. 25A (1991) 2771-2806. 

Atmospheric Reaction Mechanism. In the atmosphere the reaction subsequent to OH radical attack have not been unambiguously determined. It Is presumed that the radicals formed will Initially react with O2 and ultimately produce Cl or Br atoms or CIO or BrO radicals. The photolysis of CFCI3 and CF2CI2 under laboratory conditions leads ultlMtely to the formation of COFCl and C0F , respectively (180, 181) ... 

Atmospheric Reaction Mechanisms. The atmospheric reactions subsequent to the Initial attack by the OH radical now appear... 

Atmospheric Reaction Mechanisms. There is little information on the reaction steps subsequent to OH radical attack occurring In the atmosphere. Gay al. (214) have monitored products from the NOx photooxldatlon of a series of chlorinated ethenes, but the amount of reaction and products formed by reaction with O3 are not known. Howard (76) has postulated several reaction mechanisms which may occur under atmospheric conditions but In view of the lack of data further discussion would be purely speculative. 

Atmospheric Reaction Mechanisms. There is no definitive Information as to the subsequent reaction steps after this Initial reaction, and hence the following mechanism for C2H2 la completely speculative ... 

Atmospheric Reaction Mechanisms. There is still little definitive experimental data available on the subsequent atmospheric fates of the Initially formed OH-aromatlc adducts. However, benzaldehyde, benzylnltrate, cresols, nltro-toluenes, hydroxynltrotoluenes, and peroxyacetyl nitrate have been detected as gas phase products In NO -toluene-alr photo-oxldatlons (277-283). The following mechanism fits most of the experimental product data and Is consistent with the available kinetic data (taking toluene as an example) ... 

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