Peroxidation Of Cumene And Cyclohexylbenzene

Alkylbenzene hydroperoxides are the key intermediates in many important chemical processes where cumene hydroperoxides are the intermediates in the phenol/acetone process and cyclohexylbenzene peroxidation is the key step in the development of phenol/cyclohexanone coproduction technology.The noncatalytic reaction of cumene and cyclohexylbenzene in liquid phase was studied in this dissertation which includes the kinetic law of the oxidation reaction and the main and side reaction kinetic model at low temperature,the peroxide process conditions were also optimized.For the cumene oxidation system,the optimized reaction conditions were obtained through series experiments in which the stirring speed is 1000 rpm,0.0625 wt%NaHCO3 aqueous solution is added as an alkaline additive,the oxygen concentration in the vent is controlled between 3%to 5%,the reaction temperature is between 90? to 110? while the initiator concentration is between 5%to 15%.It was also proved that a small amount of circulating impurity isopropyl cyclohexane had no effect on the oxidation reaction.The main and side reaction kinetics model of cumene was established based on the chain radical reaction mechanism at low temperature.For the cyclohexylbenzene oxidation system,all main and by-products were quantified by high performance liquid chromatography in view of the poor thermal stability of hydroperoxide.The effects of temperature and initiator concentration on the liquid-phase peroxidation of cyclohexylbenzene were investigated under the condition of excluding mass transfer.It was found that the conversion of cyclohexylbenzene and selectivity of cyclohexylbenzene hydroperoxide were greatly affected by temperature while excessive initiator concentration doesn't further accelerate the reaction.The empirical model was used to establish the apparent kinetic model of peroxidation of cyclohexylbenzene based on the analyzed free radical reaction mechanism and the corresponding reaction path.The kinetic model parameters indicate that the main reaction process for generating cyclohexylbenzene hydroperoxide is a zero-order reaction.The established low-temperature reaction kinetic models were used to simulate the oxidation process in the hydroperoxide production process respectively.The reactor operation scheme was optimized by simulation calculation and then the process conditions and stream parameters of each unit in the oxidation process were determined,the material balance calculation was also completed.