Abstract: The effects of Ru and Cu promoters on the textural properties, phase composition, reduction and carburization behavior, and catalytic performance of Fe-based Fischer-Tropsch synthesis (FTS) catalysts without K promoter were investigated. The catalysts were characterized by N₂ physical adsorption, X-ray diffraction, H₂ and CO temperature-programmed reduction, Mössbauer effect spectroscopy. The FTS performance of the catalysts was tested in a fixed-bed reactor under the conditions of n(H₂)/n(CO) = 2.0, t = 260 ^oC, p = 1.5 MPa and GHSV = 2000 h^-1. The results indicated that both Ru and Cu enhance the dispersion of iron oxides and facilitate the reduction and carburization of the catalysts, which was more obvious for the Cu promoter. Ru and Cu both increase the activity of the catalysts to some extent. Besides, the Cu promoter increased the C₅₊ selectivity and hindered the CH₄ formation while Ru exhibited the opposite trend.

Key words: Fischer-Tropsch synthesis, ruthenium, copper, promoter, iron-based catalyst, fixed-bed reactor