Tuning surface oxygen group concentration of carbon supports to promote Fischer-Tropsch synthesis

Surface oxygen groups of carbon materials has been validated to be necessary for the synthesis of supported catalysts. Herein we report that the activity and selectivity of activated carbon-based material supported Co catalysts can be tuned by modifying the surface oxygen group concentration. As the groups were cleansed by H-2 at 1173 K, the FTS activity dropped from 8.4 to 4.0 mmol CO/(gcat.h). Whereas a following oxidation procedure could restore the FTS activity by regenerating the groups. Among which the HNO3 treatment exhibited the best effect with a remarkable elevation of activity (from 4.0 to 13.6 mmol CO/(gcat.h)) and C5+/ROH combined selectivity (64.9 C%). Characterization methods proved that the rationale behind which should be attributed to the increased Co dispersion/reduction degrees and CO/H-2 uptakes facilitated by the surface oxygen groups, and it exhibited that the activity of FTS increased as the surface oxygen group concentration and acidity were elevated.

Automated summary

The surface oxygen groups of carbon materials are necessary for the synthesis of supported catalysts. The activity and selectivity of activated carbon-based material supported Co catalysts can be tuned by modifying the surface oxygen group concentration. Further, regeneration of surface oxygen groups can restore the FTS activity of the catalysts.