The high-temperature oxidation of 1,1,1-trichloroethane can, under cer
tain conditions, form the highly toxic byproduct phosgene. Potential r
outes of phosgene formation during the high temperature post-flame oxi
dation of 1,1,1-trichloroethane are investigated. These include photol
ysis reactions, heterogenous wall reactions, reactions of carbon monox
ide and molecular chlorine, and high temperature oxidation reactions.
Experiments using both extractive and in situ measurement techniques,
along with chemical kinetic studies, indicate that phosgene is formed
directly in the gas phase as a product of 1,1,1-trichloroethane oxidat
ion. We measured up to 29% conversion of 1,1,1-trichloroethane to phos
gene at an injection temperature of 1160K and a residence time of 0.1
s. The chemical kinetic model suggests that 1,1,1-trichloroethane conv
ersion to phosgene is strongly dependent on temperature and is weakly
dependent on initial concentration, equivalence ratio, and residence t
ime.