Kinetic and mechanistic study on the thermal isomerization of ocimene in the liquid phase

The rate of thermal isomerization of ocimene in the liquid phase has been investigated in the range 90–150 °C. The rate constant for the disappearance of ocimene may be expressed by k = 1. 3 × 10¹⁰e^{– 11994. 2/T}(min^{– 1}), from which we can infer that the activation energy is 99.7 kJ mol^–1 and the pre‐exponential factor is 1.3 × 10¹⁰ min^–1. The half‐life for the disappearance of ocimene may be expressed by t_1/2 = 5. 2 × 10^{– 11}e^{11994. 2/T}(min). The conclusion has been supported by the study results that the ocimene is safe when temperature is below 100 °C. A discussion of the mechanism concerning the conversion is included. Copyright © 2011 John Wiley & Sons, Ltd.