Fabrication of highly active and durable Co/Al2O3 Fischer–Tropsch catalysts via coordination-assisted impregnation strategy

Optimizing metal nanoparticle size, dispersion, accessibility, and metal-support interaction has proven impactful for Fischer-Tropsch synthesis (FTS) activity, selectivity of long-chain hydrocarbons and stability. Herein, the Co/Al 2 O 3 -CAI catalyst was successfully prepared by a coordination-assisted impregnation strategy. Compared with Co/Al 2 O 3 -EWI catalyst prepared by traditional impregnation method, the Co/Al 2 O 3 -CAI catalyst displayed superior FTS performance with a low methane selectivity (3.2 %) and surprisingly high C 5+ hydrocarbons selectivity (94.0 %) within 200 h reaction time. The catalyst remained excellent stability with ca. 40 % CO conversion even after 1600 h on stream. It revealed that the high dispersion of cobalt species as well as reduced CoAl 2 O 4 spinel could be achieved via a coordination-assisted impregnation strategy, which provide the increased number of surface-exposed Co sites. Meanwhile, the relatively strong metal-support interaction facilitated surface confinement of cobalt species and electron transfer, guarantying catalyst stability under long-term FTS process. This work provides a new insight into the design of highly efficient and stable catalysts for FTS reaction.