Copper, potassium promoted iron on metallosilicate and aluminum oxide supports synthesized via a non-hydrolytic sol-gel for Fischer-Tropsch

Abstract

We developed a promoted iron based catalyst that converts 20% more CO to diesel than the unpromoted counterparts. The synthesis involves a non-hydrolytic sol-gel method (NHSG) and 0.04 g g−1 copper and 0.02 g g−1 potassium as promoters. The iron catalyst supports included cerium and zirconium metallosilicates and Catalox and Dispal commercial aluminum oxides from Sasol. At 325 ∘C and 20 bar, CO conversion over the Fe/Ce/SiO2-K,Cu, exceeded 85% while at the same conditions it was only 68% over the unpromoted catalyst. Fe/Zr/SiO2-K,Cu converted less CO than the cerium-silicate (75%) but the unpromoted zirconium-silicate only converted 43% of the CO. The conversion and selectivity of the Catalox was about the same as the cerium-silicate, while the Dispal performance was equivalent to the zirconium-silicate. This study also highlights the importance of support and promoters in FTS, demonstrates the potential of the NHSG method to synthesize promoted iron catalysts with various supports and lays the foundation for developing efficient and stable catalysts for converting syngas to hydrocarbons.