Fischer-Tropsch synthesis on Co-Al 2 O 3 -(promoter)/ZSM5 hybrid catalysts for the production of gasoline range hydrocarbons

The Fischer-Tropsch synthesis (FTS) reaction was investigated for the direct production of gasoline range hydrocarbons (C 5 -C 9 ) from syngas on Ru-, Pt- and La-promoted Co-Al 2 O 3 /ZSM-5 (Si/Al=25) hybrid catalysts prepared by co-precipitation method in a slurry. The hybrid catalysts were characterized by BET surface area, XRD, H 2 -TPR and NH 3 -TPD analyses. Their physicochemical properties were correlated with the activity and selectivity of the catalysts. The promoted Co-Al 2 O 3 -(promoter)/ZSM-5 hybrid catalysts were superior to the unpromoted Co-Al 2 O 3 / ZSM-5 catalyst in terms of better C 5 -C 9 yield. In particular, the Co-Al 2 O 3 -Pt/ ZSM-5 hybrid catalyst exhibited the highest catalytic activity with a low C 1 and olefin selectivity and a high C 5 -C 9 selectivity. It could be due to not only a higher value for the reduction degree by H 2 -TPR, but also assigned to weak acidic sites of a low temperature desorption peak by NH 3 -TPD.