Fe-Co-K/SiO_2催化剂催化F-T合成本征动力学的研究

Intrinsic Kinetics of Fischer-Tropsch Synthesis over Fe-Co-K/SiO_2 Catalyst

采用浸渍法制备了Fe-Co-K／SiO2催化剂。在等温积分反应器中，在温度518～541K、压力1．00～2．60MPa、进料中n（H2）：n（CO）=1．12～3．23、气态空速3000～4800h^-1的条件下，研究了在Fe-Co-K／SiO2催化剂上的F～T合成本征动力学。F-T合成中CO2的生成量很少，水煤气变换反应可不予考虑，生成烃为主要反应。以CO转化率的计算值和实验值的残差平方和为目标函数，采用Levenberg-Maquardt法对动力学参数进行优化，得到了F-T合成本征动力学模型参数，反应的活化能为78．9kJ／mol。在Fe-Co-K／SiO2催化剂上的F-T合成本征动力学模型的计算值与实验值的平均偏差为8．27％，模型的计算值与实验值符合较好。

Fe -Co -K/SiO2 catalyst was prepared by impregnation method. Intrinsic kinetics of Fischer- Tropsch（ F- T） synthesis on the catalyst was studied in an isothermal integral reactor under conditions of temperature 518 -541 K, pressure 1.00 -2.66 MPa, n（H2） ： n（CO） in feed 1.12 - 3.23 and gas hourly space velocity 3 000 - 4 800 h - 1. Since amount of CO2 produced in the F - T synthesis is negligible, water gas shift reaction can be ignored. Productions of hydrocarbons are main reactions in the F -T synthesis. Using residual sum of squares of experimental data and calculated data of CO conversion as object function, optimization of the model parameters was carded out by Levenberg - Marquardt method. Apparent activation energy of the reaction is 78.9 kJ/mol. The average deviation between experimental data and the calculated is 8.27 %. The model of intrinsic kinetics can truly simulate the experimental process.