Kinetics Research Of Alkyl Benzene Oxidation Process Catalyzed By Ionic Liquid

Phenol is an important chemical raw material. worldwide, Ninety percent of phenol are produced by cumene method. Cumene oxidation process is the key reaction for the cumene method to phenol.The study of cumene oxidation process can deepen the understanding of oxidation reaction, help to promote the oxidation to polyphenol preparation process.Ionic liquid which has the advantages of stable chemical properties, wide range for temperature operation range and less volatile, has been widely used in the field of catalysis. This paper will study on process conditions of cumene oxidation processand1,3-diisopropylbenzene oxidation process catalyzed by ionic liqid. Basis on the process conditions study, in-depth research will be given in1,3-diisopropylbenzene oxidation process intrinsic kinetics and the kinetics model which was gotten from the research is consistent with the experimental data.At first, this paper established the high performance liquid chromatography analysis method for the oxidation fluid, the main analysis conditions were:the proportion of mobile phase was V (ethane): V (isopropyl alcohol)=95:5, flow rate was1.0ml/min. The wavelength of uv detection was257nm, column temperature between15to25℃, sample size was3μl. Analysis time for cumene oxidation liquid was10min and that for1,3-diisopropylbenzene oxidation liquid was25min.Secondly, the influence of process conditions on the cumene oxidation reaction which included reaction pressure and temperature, addition of CHP, Na2CO3solution concentration was studied by single factor experiment. Optimum process conditions were:addition of IPB was1L, the addition dosage of the initiator for CHP is25g, add25g Na2CO3aqueous solution whose mass fraction was4%, reaction temperature was105℃, the pressure was0.5MPa, the stirring speed of reaction kettle was1000r/min, the air flow was300L/hr. The reaction proceeded8hours under the optimum process conditions, IPB conversion rate can reach31.3%, selectivity of the main product CHP was90.8%。Thirdly, the research on1,3-diisopropylbenzene oxidation process catalyzed by basic ionic liquid [bmim]OH was proceeded by single factor experiment. through comparative analysis with the result of the experiment, the research found that the optimum technological conditions were:the addition amount of m-DIPB was1kg, CHP was25g, the addition of catalyst for basic ionic liquid [bmim]OH was5g, the reaction temperature was95℃, the reaction was0.5MPa, the stirring speed of reaction kettle was1000r/min, the air flow was300L/hr. The reaction proceeded30hours under the optimum process conditions, m-DIPB conversion rate can reach98.3%, the selectivity of DHP was36.1%, the selectivity of HHP+DHP+DCL were80.1%.Furthermore, Through the analysis of the thermodynamic calculation, The reversibility of all the reactions which were involved in1,3-diisopropylbenzene oxidation system was determined, they are both spontaneous irreversible processes. Based on the process condition analysis, the main and side reaction in the reaction system were determined and the reaction network of1,3-diisopropylbenzene oxidation system had been proposed.Finally, under the condition of excluding diffusion factor, the1,3-diisopropylbenzene oxidation reaction kinetics experiments was proceeded. According to the thermodynamics analysis and literature research, intrinsic kinetics model of oxidation reaction was chosen. Through the process of optimizing value, kinetics model parameters were obtained. At last, the intrinsic kinetics model that were consistent with kinetics experimental datas were obtained.