The effect of ceria promotion on the performance of Co/Al2O3 catalyst was evaluated in a high pressure fixed bed reactor for Fischer–Tropsch (FT) synthesis at close industrial conditions. Ce–Al2O3 supports with a molar ratio of Al/Ce = 8 were prepared by two different methods: one by co-precipitation of cerium and aluminum precursors in water-in-oil microemulsion and the other one by aqueous impregnation of cerium nitrate on commercial alumina. These supports, together with the unmodified alumina carrier, were used to prepare four cobalt-based catalysts. These catalysts were characterized by XRD, SEM, EDX, TEM, N2 adsorption/desorption, TPR and chemisorption techniques. The results show that the presence of CeO2 on the surface of the support favors the reducibility of cobalt oxides with a shift down in reduction temperature of about 70 °C. The catalytic evaluation of the catalysts revealed that cerium addition by impregnation increases the activity and selectivity to C5+ catalyst in FTS. The catalyst synthetized by microemulsion show lower catalytic performance. Nevertheless, the catalytic property of this material can be improved by increasing the crystalline micro-domains size of CeO2.
Bibliographical noteFunding Information:
The authors would like to thank the financial support provided by Swedish International Development Cooperation Agency (SIDA) Ref. 75000553. COST Action: CM1101 for the financial support for a Short Term Scientific Mission at “Centro de Investigación en Materiales Avanzados”, S.C. (CIMAV-Unidad Monterrey), Mexico.
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- Cerium promoter
- Cobalt–alumina catalyst
- Fischer–Tropsch synthesis