Abstract: Cobalt-based catalysts supported on silica and alumina were prepared respectively and tested by a slurry-bed Fischer-Tropsch synthesis reactor. These catalysts were characterized by N2-physisorption, H2-TPR, CO chemisorption, XRD, SEM, pyridine adsorption infrared spectroscopy and reduction degree. The results show that the silica support with larger pore size and acid-free benefits the dispersion of Co, larger surface area and reduction degree of the catalysts, resulting in higher activity and C5+ selectivity. It is found that for silica support catalyst the larger the pore size, the larger the dispersion and surface area of metal Co; the weaker the acidity, the higher the C5+ selectivity. The results indicate that support does not affect the catalyst deactivation rate, but the initial reaction rate of silica catalyst is significantly higher than the alumina catalyst.

Key words: Fischer-Tropsch synthesis, cobalt-based catalysts, slurry-bed reactor, supports, activity, selectivity