PNNL

Abstract

The ozonolysis of propene has been investigated in a temperature controlled reaction chamber at 295, 260, and 230 K. Experiments were performed using a total zero air pressure of 760 Torr (STP) and propene/ozone reactant mixing ratios ranging from 2.3 to 23. ppmv. An analysis of FTIR spectra collected at the conclusion of each reaction revealed that methane was formed with a yield of 0.14 for all the temperatures investigated. In addition, the yield of HCHO decreased from 0.56 to 0.36 upon cooling from 295 to 230 K, whereas the yield of HCOOH increased from 0.11 to 0.53. Experiments were also performed using an excess of cyclohexane and it was found that the formaldehyde yield was 0.68 plus or minus 0.05 and 0.51 plus or minus 0.04 at 295 and 260 K, respectively. Finally, to more fully understand the reaction energies involved in product formation we have performed molecular orbital calculations of reactants, stable intermediates, and products.