Abstract: Co-ZrO2 co-precipitation catalysts were used to investigate the effect of the pretreatment atmosphere on the texture, crystal phase, and morphology of catalysts. The result indicated that the catalysts were sintered evidently above 500 ℃ in Ar and H2 atmospheres. After the pretreated catalysts were exposed to air, all the cobalt species were in existence as Co3O4 phase and the particle shape of the catalysts changed little. The pretreatment in CO atmosphere led to serious cracking and obvious coke deposition, and the catalyst mainly contained the cubic cobalt species. The pretreatment of the catalyst with syngas gave rise to serious sintering and trace of fragmentation, and it was found that the cubic and hexagonal cobalt co-existed in the catalyst.

Key words: Cobalt, Zirconia, Pretreatment atmosphere, FT catalyst