摘要: In this research work, two 30%(Co-Mn)/TiO₂ catalysts were prepared using sol-gel (catalyst A) and co-precipitation (catalyst B) methods. The activity and selectivity to C_2~4 light olefins in Fischer-Tropsch synthesis (FTS) has been studied in a fixed-bed reactor under different operational conditions. These operational conditions were: temperature 220~280 ℃, and total pressure from 0.1~0.6 MPa. The optimum operating conditions were investigated after steady state. As the results shown, the catalyst A was more selective to C_2~4 olefins (58.7% in 260 ℃) and catalyst B was more selective to C₅₊ hydrocarbons. Characterization of both catalysts was carried out by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and N₂ adsorption-desorption measurements methods.