Fischer-Tropsch synthesis: the effect of Al2O3 porosity on the performance of Co/Al2O3 catalyst

Al2O3 was calcined at different temperature to get the support with different pore size. Co/Al2O3 catalysts with different pore size were prepared by incipient wetness impregnation technique. BET measurements, XRD, TPR, H2-TPD and O2 titration were used to characterize these catalysts. The pore size of support Al2O3 was found to have a significant effect on Co3O4 crystallite diameter, catalyst reducibility and Fischer-Tropsch synthesis (FTS) activity. The larger pore size enhanced the formation of bigger crystallite diameter Co3O4 on the catalyst and the occurrence of larger pore size catalyst decreased the number of cobalt active sites on the surface of the catalyst and the reducibility of the catalysts, resulting in the decrease in FTS activity.