Effect of niobium promoter on iron-based catalyst for Fischer-Tropsch reaction
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摘要: Niobium-promoted Fe/CNTs catalysts were prepared using a wet impregnation method. Samples were characterized by nitrogen adsorption, H2-TPR, TPD, XRD and TEM. The Fischer-Tropsch Synthesis (FTS) was carried out in a fixed-bed microreactor at 220 ℃, 1 atm and H2/CO=2 for 5 h. Addition of niobium into Fe/CNTs increased the dispersion, decreased the average size of iron oxide nanoparticles and the catalyst reducibility. Niobium-promoted Fe catalyst resulted in appreciable increase in the selectivity of C5+ hydrocarbons and suppressed methane formation. These effects were more pronounced for the 0.04%Nb/Fe/CNTs catalyst, compared to those observed from other niobium compositions. The 0.04%Nb/Fe/CNTs catalyst enhanced the C5+ hydrocarbons selectivity by a factor of 67.5% and reduced the methane selectivity by a factor of 59.2%.
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关键词:
- CNTs /
- iron /
- niobium /
- Fischer-Tropsch synthesis
Abstract: Niobium-promoted Fe/CNTs catalysts were prepared using a wet impregnation method. Samples were characterized by nitrogen adsorption, H2-TPR, TPD, XRD and TEM. The Fischer-Tropsch Synthesis (FTS) was carried out in a fixed-bed microreactor at 220 ℃, 1 atm and H2/CO=2 for 5 h. Addition of niobium into Fe/CNTs increased the dispersion, decreased the average size of iron oxide nanoparticles and the catalyst reducibility. Niobium-promoted Fe catalyst resulted in appreciable increase in the selectivity of C5+ hydrocarbons and suppressed methane formation. These effects were more pronounced for the 0.04%Nb/Fe/CNTs catalyst, compared to those observed from other niobium compositions. The 0.04%Nb/Fe/CNTs catalyst enhanced the C5+ hydrocarbons selectivity by a factor of 67.5% and reduced the methane selectivity by a factor of 59.2%.-
Key words:
- CNTs /
- iron /
- niobium /
- Fischer-Tropsch synthesis
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