Syngas to FCC-like gasoline range hydrocarbons with upgraded light olefin selectivity catalyzed by readily synthesized Fe-MOF

Abstract

The global trend toward sustainability is due to the growing demand for synthetic chemicals and fuels relying on fossil crude oil with the associated concerns of climate change. The Fischer-Tropsch synthesis (FTS) process is a key sustainable pathway for supplying light olefins, gasoline, and other petrochemicals using green hydrogen and energy. Here we report a simple, green, cost-effective synthesis strategy to prepare an iron-based metal–organic framework (Fe-BTC MOF) at room temperature with a remarkable porous structure analogous to the commercially available Basolite F300. The catalyst shows a 97% syngas conversion to gasoline-range hydrocarbons (C5-C12) at high temperatures, with a selectivity of 48.3%, yield of 28%, low methane selectivity (15.5%) and low C13+ selectivity (1%). In addition, the catalyst is 29% selective to light olefin (C2-C4=), yielding 17%, besides an olefin/paraffin ratio (O/P) of 4.3 with 81% olefin selectivity of the C2-C4 fraction. The resulting gasoline is equivalent to gasoline produced by Fluid Catalytic Cracking (FCC) of crude oil. The highest C5-C12 selectivity reached 63.6%, yielding 12% at 29% CO conversion. The Fe-BTC/C catalyst showed excellent stability for time on stream >100 h and a high gas hourly space velocity (GHSV) value of 20000 mL g-1cat h−1 with an Fe-time yield of 165 µmolCO g-1Fe s−1. The prepared Fe-BTC catalyst, with a 2-fold larger pore volume than the previously prepared Fe-MIL-88B catalyst, has a higher olefin production capability by 2-fold, 7-fold higher O/P for the light fraction and 2.3-fold higher C5+ selectivity. The sustainable synthesis of catalysts with improved porous structure may significantly foster FTS technology for being economically practical to be scaled up and commercialized for national fuel and olefin production projects.