FISCHER-TROPSCH SYNTHESIS IN A STIRRED-TANK SLURRY REACTOR

Three precipitated iron catalysts were evaluated in a stirred tank slurry reactor to determine their performance during Fischer-Tropsch synthesis under steady-state conditions. High syngas conversions (>80%) were achieved in all three tests, and the catalyst deactivation rates were moderate (1.3-2.1% per day), Selectivities of all three catalysts were fairly stable with time (up to 560 h of continuous testing). Methane selectivity (2.1-3.7 wt% of total hydrocarbons) and gaseous hydrocarbon (C-2-C-4) selectivity (9-15 wt%) were very low, whereas the selectivity of C-5(+) hydrocarbons was high. Methane and gaseous hydrocarbon selectivities obtained in these tests are comparable to those obtained in the two most successful slurry bubble column reactor tests. The activity of one of these three catalysts (100 Fe/5 Cu/6 K/24 SiO2, in parts per weight) was higher than that of any other known iron Fischer-Tropsch catalyst developed for slurry phase operation.