The effect of surface acidic and basic properties of highly loaded Co catalysts on the Fischer–Tropsch synthesis

Highly loaded cobalt catalysts (80% by weight) with different supports (SiO2, Al2O3, ZrO2 and MgO) were prepared by the co-precipitation technique for Fischer–Tropsch synthesis (FTS). Microcalorimetric adsorptions of NH3, CO2, CO and H2 showed that the surface acidity/basicity significantly affected the surface properties of supported Co, as evidenced by the changes of strengths of adsorption of CO and H2 on Co, which in turn affected the FTS performance. The appropriate ratio (~ 1.2) of heats for the adsorption of CO and H2 on Co seemed important in determining the FTS activity.

The catalytic performances of FTS reactions on Co were found to be significantly affected by the surface acidic and basic properties of supports, which influenced the strengths of adsorption of CO and H2 on supported Co. The appropriate ratio of heats for the adsorption of CO and H2 seemed to be important for supported Co to exhibit the high FTS activities for the synthesis of heavy hydrocarbons.Figure optionsDownload as PowerPoint slideHighlights
► Highly loaded cobalt catalysts were prepared for Fischer–Tropsch synthesis (FTS).
► The FTS activities on Co were significantly affected by supports.
► Surface acidity and basicity of supports affected the adsorption of CO and H2 on Co.
► Relative adsorption strengths of CO and H2 on Co affected FTS activity.