Fischer–Tropsch Synthesis Intensification in Foam Structures

This paper investigates the intensification of Fischer–Tropsch synthesis (FTS) in open-cell foam structures. For confirming this point, the metallic foams with different alloy (aluminum and FeCrAl), pore density (10–40 ppi), and (20% Co–0.5% Re)/Al 2 O 3 catalyst layer thicknesses were prepared. Catalytic results of aluminum foams show excellent thermal behavior but catalyst coatings thicker than ∼70 μm suffer from catalyst effectiveness loss, increasing methane selectivity, and decreasing C 5+ hydrocarbon selectivity. Conversely, FeCrAl foams also exhibited a similar critical maximum catalyst layer thickness but with diffusional and thermal limitations resulting in both temperature and selectivity runaways at higher thicknesses. Finally, the observed good thermal control and tortuosity of the narrow porous structure for aluminum foams permitted enhanced production of C 5+ hydrocarbons to 87 kg C5+ m –3 h –1 at 250 °C, 26% higher than the productivity obtained with parallel channel aluminum monolith coated with a similar catalyst amount.