Fe_2O_3-K_2O催化剂上乙苯脱氢反应动力学  

Kinetics of Dehydrogenation of Ethylbenzene to Styrene on Fe_2O_3-K_2O Catalyst

作　　者：何淡云[1] 黄小荥[1] 祝以湘[1] 戴深峻[2,1] 

机构地区：[1]厦门大学物理化学研究所 [2]厦门大学化工系

出　　处：《厦门大学学报（自然科学版）》1992年第6期635-640,共6页Journal of Xiamen University：Natural Science

摘　　要：Fe_2O_3-K_2O双组份催化剂在反应温度580～640℃,液体空速0.5～2.5h^(-1),水/乙苯(体积比)1～3范围内乙苯脱氧反应动力学数据。列出主副反应单位或双位吸附的各种反应类型,用线性回归分析法进行判别以确定反应模型和估算各参数值,进一步用数值积分法优化计算不同温度下的反应速度率常数,吸附系数,频率因子和活化能。结果表明:双组份催化剂活性高,但苯乙烯选择性差,副产物苯和甲苯同时从平行反应和联串反应产生,其中大部份来自联串反应,主副反应均用双位吸附单分子反应模型较为合适。The kinetics of ethylbenzene dehydrogenation on binary Fe2O3-K2O catalyst was studied under the reaction conditions of 580-640 ℃ ,LHSV 0. 5-2. 5 h-1 ,H2O/EB(vol. )1-3. The different kinetic models of single-site and dual-site adsorption mechanisms for ethylbenzene dehydrogenation and the side-reaction were proposed. The best model was first ascertained by linear regression method, then the rate constants and adsorption constants were evaluated by numerical integration method. The activation energies and frequency factors of the dehydrogenation and the side- reactions were calculated by using the Arrhenius relation. The results indicate that the dual-site adsorpion unimolecular reaction model was best fit for the mechanism of ethylbenzene dehydrogenation and side -reactions, and that by-products, benzene and methylbenzene,were formed from both the parallel reaction of ethylbenzene and the successive reaction of styrene, but mainly from the latter.

关 键 词：乙苯 脱氢 动力学 氧化铁 催化剂 

分 类 号：O625.11[理学—有机化学]