醇溶剂中TS-1催化丙烯环氧化的本征动力学与反应机理研究

Study on Reaction Mechanism and Intrinsic Kinetics of Epoxidation of Propylene Catalyzed by TS-1 in Alcohols

研究了在三种不同醇溶剂(甲醇、异丙醇和仲丁醇)水溶液中TS-1催化丙烯过氧化氢环氧化反应的本征动力学,反应条件为温度30~60℃,丙烯压力0.4~0.6MPa.根据实验现象和各组分在TS-1上的吸附特点建立了该反应的Eley-Rideal机理模型,环氧化反应在吸附态的H2O2分子与游离态的丙烯分子之间进行,表面反应为速度控制步骤.通过实验数据对机理模型进行了参数估值,检验结果表明拟合效果较好,平均偏差在10%以内.最后对过程进行了进一步讨论,为该过程的工业化提供了依据.

The intrinsic kinetics of the epoxidation of propylene with hydrogen peroxide catalyzed by titanium silicalite-1 (TS-l) in alcohols aqueous solution was investigated. The reaction was carried out in a semi-batch stirred-tank at T=30-60°C, p=0.4-0.6 MPa, with three different alcohol aqueous solution as solvents respectively, which included methanol, isopropanol and secondary butyl alcohol. According to experimental phenomenon and absorption characteristic of components on the catalytic site, Eley-Rideal mechanism model was established, in which hydrogen peroxide molecule absorbed on the catalytic site reacts with dissociated propylene molecule, and surface reaction is rate-controlling step. Parameter estimation was done by using experimental data. The results show that obtained model fits well with experimental data, the average deviation between experimental and calculated date is less than 10%. From the model obtained, the reaction mechanism was discussed further and the study results provide important information for commercial and process design.