Thermal isomerization of cis ‐ or trans ‐2‐butene. The unimolecular elimination of hydrogen from cis ‐2‐butene around 500°C

An analytical and kinetic study of the thermal reaction of cis ‐ or trans ‐2‐butene has been performed in a static system over the temperature range of 480–550°C and at a low extent of reaction and initial pressures of 10–100 torr. The rate constant of the unimolecular cis–trans isomerization of cis ‐2‐butene, determined under the conditions\documentclass{article}\pagestyle{empty}\begin{document}$$k_{ct} = 10^{13.6 \pm 0.3 - 62,000 \pm 1000/2.3{\rm RT}} {\rm sec}^{- 1} $$\end{document}(2.3 RT in cal/mole) is in good agreement with previous measurements made at lower pressures. A comparison between the formation rates of hydrogen from the thermal reactions of cis ‐ and trans ‐2 butene around 500°C leads to the rate constant value\documentclass{article}\pagestyle{empty}\begin{document}$$k_m = 10^{13 \pm 0.5 - 65,500 \pm 2000/2.3{\rm RT}} {\rm sec}^{- 1} $$\end{document}(2.3 RT in cal/mole) for the unimolecular 1,4hydrogen elimination from cis 2butene.