Fischer-Tropsch Synthesis: Effect of Reaction Temperature for Aqueous-Phase Synthesis Over a Platinum Promoted Co/Alumina Catalyst

The effect of reaction temperature on the performance of a traditional Fischer-Tropsch cobalt catalyst (0.5 % Pt-25 % Co/Al2O3) was investigated during aqueous-phase Fischer-Tropsch synthesis (AFTS) using a 1 L stirred tank reactor in the batch mode of operation. The CO conversion rate of the catalyst was found to increase monotonically with increasing reaction temperature. At lower temperatures oxygenate selectivity was high. With increasing the reaction temperature, oxygenate selectivity decreased and the selectivity to hydrocarbons increased. Carbon dioxide and methane selectivity also increased with reaction temperature and the corresponding higher hydrocarbon (C-5+) selectivity decreased. For comparison, the CO conversion rate of the catalyst was also tested using C-30 oil as a solvent, and similar activation and reaction conditions were utilized in the batch mode of operation. Slightly higher CO rate was observed with C-30 oil as a solvent than with the water.