TS-1催化丙烯环氧化过程中环氧丙烷的开环反应研究

环氧丙烷的开环反应是TS-1催化丙烯环氧化制备环氧丙烷过程的副反应,本文对醇溶剂中开环反应进行了研究,分析了该反应的酸性催化机理,酸性主要来自TS-1与H2O2的相互作用产生的质子酸,醇溶剂能显著增强体系酸性从而加快环氧丙烷的开环反应速度。三种醇按酸性增强程度的顺序为甲醇>异丙醇>仲丁醇。根据反应的Eley-Rideal 机理（吸附态的PO与游离态的醇发生开环反应,表面反应为控制步骤）再考虑各组分在TS-1上的吸附特点提出反应的机理模型。用实验数据进行了回归,得到了令人满意的动力学方程式,实验数据与模型计算值平均偏差小于10％。

STUDY ON RING-OPENING OF PROPYLENE OXIDE IN EPOXIDATION OF PROPYLENE CATALYZED BY TS-1

In this paper, titanium silicate-1 (TS-1) catalyzed ring-opening of propylene oxide in process of propylene epoxidation using alcohol as solvents was studied. The ring-opening is the side reaction of epoxidation. The acidic reaction mechanism and the effect of different alcohols on ring-opening reaction were discussed in detail. Acidity mainly originates from proton acid produced by the interaction of active sites of TS-1 with H2O2. Alcohol solvents can obviously enhanced acidity. The order of three alcohol solvents according to extent promote acidty is methanol>iso-propanol>sec-butanol. With assumption of Eley-Rideal mechanism that PO molecule absorbs on the catalytic site reacts with dissociated solvent molecule, and surface reaction is the rate-controlling step, also consider absorptivity of components on the TS-1, a mechanism model was proposed. After parameter estimation, relevant kinetics equation was obtained which well fit the experimental data. The average relative deviation between experimental and calculated reaction date is less than 10%.