The thermal reaction of 2‐pentene around 500°C at low extent of reaction

Abstract

The thermal reaction of 8-pentene (cis or trans) has been performed in a static system over the temperature range of 470°-535"C a t low extent of reaction and for initial pressures of 20-100 torr. The main products of decomposition are methane and 1,3-butadiene. Other minor primary products have been monitored: trans-2-pentene, trans-and cis-2-butenes, ethane, 1,3-pentadienes, 3-methyl-l-butene, propylene, 1-butene, hydrogen, ethylene, and I-pentene. The initial orders of formation, 0.8-1.1 for most of the products and 1.5-1.8 for 1-pentene, increase with temperature. The formation of the products and the influence of temperature on their orders can be essentially explained by a free radical chain mechanism. But cis-trans or trans-cis isomerization and hydrogen elimination from cis-2-pentene certainly involve both molecular and free radical processes. The formation of 1-pentene mainly occurs from the abstraction of the hydrogen atom of 2-pentene by resonance stabilized free radicals (C5Hg.).