Effect of Re and Al 2 O 3 Promotion on the Working Stability of Cobalt Catalysts for the Fischer–Tropsch Synthesis

The results of the working stability studies of cobalt catalysts based on SiO 2 and Al 2 O 3 promoted with Re and Al 2 O 3 in the synthesis of hydrocarbons from CO and H 2 in continuous tests for 200–300 h are presented. The prepared catalysts were characterized by transmission electron spectroscopy, temperature-programmed reduction with hydrogen, temperature-programmed desorption of CO, and X-ray fluorescence spectroscopy and tested at a temperature 200°C, a pressure of 0.1 MPa, and a GHSV of 100 h –1 . It was determined that a cobalt–silica catalyst promoted with Al 2 O 3 had the highest activity. It was established that the addition of Al 2 O 3 to a cobalt–silica catalyst increased the conversion of CO and selectivity for C 5+ hydrocarbons and inhibited the agglomeration of Co particles under the action of a reaction atmosphere in the Fischer–Tropsch synthesis. It was found that the initial conversion of CO increased by a factor of 2 upon the introduction of 0.1 wt % rhenium into the Co/γ-Al 2 O 3 catalyst; however, the rate of its deactivation increased in this case due to an almost twofold increase in the size of cobalt particles in the course of synthesis after operation for 300 h.