The Effect of Al2O3 Pore Diameter on the Fischer-Tropsch Synthesis Performance of Co/Al2O3 Catalyst

In order to investigate the effect of gamma-alumina pore size on the ability of alumina-supported cobalt (Co/Al2O3) catalysts in Fischer-Tropsch synthesis (FTS), ordered mesoporous alumina (OMA) samples with different pore sizes (4.8, 7.2, 9.7 and 12.6 nm) were synthesized by various methods. Co/OMA catalysts with a Co loading of 15 wt% were prepared by the impregnation method. N-2 physisorption, X-Ray Diffraction (XRD), H-2-Temperature-Programmed Reduction (H-2-TPR), and H-2 Temperature-Programmed desorption (H-2-TPD) experiments were conducted to characterize the structure and properties of these catalysts, and the catalyst structure-FTS performance relationships were also analyzed. The TOF increases with OMA pore size increase from 4.8 to 9.7 nm and decreased when the OMA pore size increased further to 12.6 nm. The C5+ selectivity of catalysts increases with OMA pore size, while the CH4 selectivity decreased with which. The Co3O4 particle size of catalysts were depended highly on the OMA pore size, which was the vital factor affecting the performance of catalyst.