The kinetics and the mechanism of the thermal decomposition of bis(trifluoromethyl) trioxide. The influence of carbonmonoxide on its decomposition

The kinetics of the thermal decomposition of CF 3 O 3 CF 3 has been investigated in the pressure range of 15–599 torr at temperatures between 59.8 and 90.3°C and also in the presence of CO between 42 and 7°C. The reaction is homogeneous. In the absence of CO the only reaction products are CF 3 O 2 CF 3 and O 2 . The rate of reaction is strictly proportional to the trioxide pressure, and is not affected by the total pressure, the presence of inert gases, and oxygen.\documentclass{article}\pagestyle{empty}\begin{document}$$ -\frac{{d[{\rm CF}_{\rm 3} {\rm O}_{\rm 3} {\rm CF}_{\rm 3}]}}{{dt}} = 2\frac{{dp}}{{dt}} = k[{\rm CF}_{\rm 3} {\rm O}_{\rm 3}{\rm CF}_{\rm 3}] $$\end{document}\documentclass{article}\pagestyle{empty}\begin{document}$$ k = 2.25 \pm 0.18 \times 10^{15} \exp (- 30,530 \pm 130\,{\rm cal}/RT)s^{ - 1} $$\end{document}The following mechanism explains the experimental results:In the presence of CO there appear CO 2 , (CF 3 OCO) 2 , and CF 3 O 2 C(O)OCF 3 as products. With increasing temperature the amount of peroxicarbonate decreases, while the amounts of oxalate and CO 2 increase. The rate of decomposition of the trioxide above a limiting pressure of about 10 torr CO is strictly first order and independent of CO pressure, total pressure, and the pressure of the products.\documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d[{\rm CF}_{\rm 3} {\rm O}_{\rm 3} {\rm CF}_3]}}{{dt}} = k*[{\rm CF}_{\rm 3} {\rm O}_{\rm 3} {\rm CF}_{\rm 3}] $$\end{document}The addition of larger amounts of O 2 to the CO containing system chaqnges the course of the reaction.