, Volume 140, Issue 3-4, pp 127-133,
Open Access This content is freely available online to anyone, anywhere at any time.

Textural Structure of Co-based Catalysts and their Performance for Fischer–Tropsch Synthesis

Abstract

Both mono- and bi-modal Co-based Fischer–Tropsch Synthesis (FTS) catalysts were prepared by incipient-wetness impregnation (IWI). XRD and N2 physisorption revealed that the catalyst with a bi-modal distribution of 2.5–17 nm had the smallest size of cobalt crystal. In this case, the Raman absorbance shifted toward lower frequencies due to the size quantization effect. Furthermore, H2-TPR indicated a lower reducibility originated from the interaction between small crystalline cobalt and silica. Such bi-modal structure catalysts showed a better FTS performance, and particularly the bi-modal mesopores catalyst presented the lowest methane selectivity, the highest activity and the highest selectivity to C5–C18 hydrocarbons, which might be due to the confinement of mesopore to the cobalt particles.

Graphical Abstract

The catalyst with a bi-modal distribution of 2.5–17 and 2.5–65 nm showed a better FTS activity, lower methane selectivity than mono-modal catalyst, particularly the bi-modal mesoporous catalyst presented the highest selectivity to C5–C18 hydrocarbons