The high temperature oxidation of tetrafluoroethylene

The high temperature oxidation of tetrafluoroethylene (C2F4) in excess argon has been studied behind reflected shock waves. Kinetic data were obtained for three fuel/oxidant ratios and all experiments were carried out in the temperature and total pressure ranges 1670–2500 °K and 4.0–6.9 atm, respectively. The rate of formation of COF2 was monitored in emission at 5.5 μ while the rate of reaction of CF2 was monitored simultaneously in absorption at 2804 A. The Arrhenius rate constant for the elementary reaction CF2+O2 5→COF2+O is given by the expression k5= (2.01±0.30) ×1013 exp(−26 500±600/RT) cm3/mole⋅sec. Based on both the simultaneous experimental measurements and analytical mechanistic considerations, it was shown that the initial rate of COF2 formation could be utilized to evaluate k5 under all experimental conditions. However, owing to the presence of competing reactions, the initial rate of reaction of CF2 could not be utilized in all cases to evaluate the elementary rate constant k5.