Propyne pyrolysis in a flow reactor: An experimental, RRKM, and detailed kinetic modeling study

The pressure-dependent rate coefficients for several reactions relevant to propyne pyrolysis were determined with ab initio quantum mechanical calcula tions and Rice-Ramsperger-Kassel-Marcus (RRKM) analyses. These reactions in clude the mutual isomerization of propyne and allene, the chemically activa ted reactions of propyne and allene with the H atom and of acetylene with m ethyl on the C3H5 potential energy surface. Propyne pyrolysis was experimen tally studied in a flow reactor at 1210 K and 1 atm. A detailed reaction me chanism, employing the current RRKM rate coefficients, is shown to accurate ly predict the experimental acetylene and methane profiles determined in th e flow reactor and literature shock-tube data of propyne and allene pyrolys is up to 1500 K.