hide
Free keywords:
Fischer-Tropsch catalysis; heterogeneous catalysis;
hierarchical porosity;syngas conversion; tandem catalysis
Abstract:
Tandem catalysis is an attractive strategy to intensify chemical processes but simultaneous control over the individual and concerted catalyst performances poses a challenge. We show that enhanced pore transport within a Co/Al2O3 Fischer-Tropsch (FT) catalyst with a hierarchical porosity enables its tandem integration with a Pt/ZSM-5 zeolitic hydrotreating catalyst in a spatially distant fashion ‒ permitting a catalyst-specific temperature adjustment ‒ albeit resembling a close active site proximity ‒ by mitigating secondary reactions of primary FT α-olefin products. This approach enables the conciliation of in situ de-waxing with a minimum production of gases (18 wt%) and an up to two-fold higher (50 wt%) selectivity to middle-distillates compared to benchmark mesoporous FT catalysts. An overall 80% selectivity to liquid hydrocarbons from syngas is attained in one step, attesting for the potential of this strategy to increase the efficiency in intensified gas-to-liquid technologies.
