Fuel, Vol.177, 197-205, 2016
MnO2 coated Fe2O3 spindles designed for production of C5+ hydrocarbons in Fischer-Tropsch synthesis
Manganese served as promoter for the Fe-based catalysts has been considered to have great potential in Fischer-Tropsch (FT) synthesis. However, many previous researchers mainly focus on the enhancement of lower olefins, primarily because the previous reported Fe-Mn spinel oxide hindered its wide applications. In this article, Fe2O3@MnO2 spindles were fabricated by coverage of hematite with MnO2 via a hydrothermal reaction and applied in FT synthesis reaction. Different from the conventional Fe-Mn catalysts, the synthesized core-shell catalysts exhibited enhanced catalytic performance, especially in C5+ hydrocarbons selectivity. It demonstrated that Mn promoter could accelerate the dissociation of CO and thus enhanced the concentration of active intermediates for chain growth. Compared with the pure Fe2O3 (Mn-free) catalyst, the selectivity toward C5+ hydrocarbons over Fe2O3@MnO2 (Mn-9) catalyst was increased from 44.6 to 66.6 wt%. Meanwhile, the undesired CH4 was decreased from 16.8 to 8.9 wt%. (C) 2016 Elsevier Ltd. All rights reserved.