添加Ce、Mo的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-K2O-BASED CATALYST

作　　者：何淡云[1] 李庆水[1] 祝以湘[1] 林仁存[1] 

机构地区：[1]厦门大学化学系,物理化学研究所厦门361005

出　　处：《分子催化》1991年第4期354-361,共8页Journal of Molecular Catalysis(China)

基　　金：中国石油化工总公司资助项目

摘　　要：对含Ce,Mo的Fe_2O_3-K_2O催化剂,即工业用XH-03催化剂,采用流动法积分反应器,在反应温度580～640℃,液体空速0.5～2.5h^(-1),水/乙苯(体积)1～3范围内测定了乙苯脱氢反应动力学数据。对主副反应列出了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,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常数、吸附系数、频率因子和活化能等。计算结果表明:用双位吸附单分子反应模型较为合适,副产物苯主要由平行反应产生,甲苯主要由串联反应产生。乙苯转化速率方程为:r_E=k_1(P_E-Ps^2/k_p)/(1+bsPs)The kinetics of ethylbenzene dehydrogenation on a Ce,Mo-promoted Fe2O3-K2O catalyst was studied under temperature 580-640℃, LHSV 0.5-2.5 h-1 and H2O/EB ( vol ) 1 - 3 . The different reaction models of single- and dual-site adsorption mechanism for ethylbenzene dehydrogenation and the side-reactions 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 dehydro genation and side-reactions were calculated by using the Arrhenius relation. The results of experiment showed that the dual-site adsorption unimolecular reaction model was fit best for the mechanism of ethylbenzene dehydrogenation. By-product benzene was formed from the parallel reaction of ethylbenzene, and methylbenzene was formed from the successive reaction of styrene. The rate equation of ethyl-benzene dehydrogenation can be simplified to rE = k1 (pE-ps2/Kp)/(1+bsps)2.

关 键 词：乙苯 脱氢 氧化铝 氧化钾 催化剂 

分 类 号：O625.11[理学—有机化学]