异丙苯液相氧化反应动力学研究

本文研究了在半间歇操作条件下,在100°—130℃的温度范围内,采用异丙苯氢过氧化物为引发剂的异丙苯液相空气氧化反应动力学.根据烃类氧化的链式自由基反应机理以及对在氧化反应中异丙苯氢过氧化物分解方式的假设,导出该氧化反应在链稳定增长阶段的反应动力学模型.根据所获得的实验结果,确定了异丙苯液相氧化反应及氢过氧化物分解副反应的速率常数、表观活化能及反应速率常数的Arrhenius关系式.由反应动力学模型计算出的异丙苯和它的氢过氧化物浓度与实验结果吻合良好.文中还讨论了在半间歇操作中存在的诱导期以及反应温度对异丙苯转化率和异丙苯氢过氧化物选择率的影响.

A Study on the Kinetics of Liquid-Phase Oxidation of Cumene

The kinetics of liquid-phase oxidation of cumene with air using cn-mene hydroperoxide as an initiator has been studied in the temperature range of 100° to 130° C for semi-batch operation. According to the chain free-radical mechanism for liquidphase oxidation of hydrocarbons and the assumed mode for the decomposition of cumene hydroperoxide, a kinetic model for the steady chain-propagation period is derived. On the basis of the experimental results obtained, the rate constants and the apparent activation energy for liquid-phase oxidation of cumene and for the side reaction of decomposition of hydroperoxide are determined. The concentrations of cumene and its hydroperoxide calculated from the kinetic model fit in satisfactorily with the experimental results. In this paper the induction period for the semi-batch operation and the effects of reaction temperature on the conversion of cumene and on the selectivity to cumene hydroperoxide are also discussed.