Modulating Fischer-Tropsch synthesis performance on the Co3O4@SixAly catalysts by tuning metal-support interaction and acidity

ZIF-67 derived catalysts for Fischer-Tropsch synthesis have attracted much attention in recent years, while there is still a potential to improve their activity and selectivity. In this work, we prepared Si/Al co-immobilized Co3O4@SixAly catalysts by in-situ doping tetraethylorthosilicate and aluminum nitrate during the synthesis of ZIF-67. The effects of different Si/Al ratios on the metal-support interaction, acidity and FTS performance were explored. Results indicated that the Co3O4@Si0Al4 catalyst exhibited the best FTS performance with the CO conversion as high as 79.9% and CTY (cobalt time yield) value of 19.5 × 10−5 molCO·gCo−1·s−1, which was ascribed to the moderate metal-support interaction and the most active Co sites. Meanwhile, the Co3O4@Si3Al1 and Co3O4@Si2Al2 catalysts exhibited higher iso-paraffin and olefin selectivity due to more acidic sites.