Pretreating Co/SiO₂ to generate highly active Fischer-Tropsch synthesis catalyst with low CH₄ selectivity

The effects of pretreatment methods (DR, R, ROR) on the microstructure of Co/SiO₂ catalysts and the activity for Fischer-Tropsch synthesis (FTS) were investigated. The pretreated catalysts were characterized by TEM, HRTEM, XRD, XPS, H₂-TPD, TG and TPR. The results showed that after the pretreatments, specific morphological of the Co species changed, forming new Co active surface species. The Co particles redispersed and the Co species was facile to be re-reduced. The Co/SiO₂ catalysts pretreated by different method showed different catalytic performance. The catalyst treated by the reduction-passivation had higher activity and C₅₊ selectivity for FTS.