| Summary: | Highly dispersed Mn⁻Ce binary metal oxides supported on carbon nanofibers (MnO<sub>x</sub>⁻CeO<sub>2</sub>/CNFs(OX)) were prepared for Hg<sup>0</sup> removal from coal-fired flue gas. The loading value of the well-dispersed MnO<sub>x</sub>⁻CeO<sub>2</sub> was much higher than those of many other reported supports, indicating that more active sites were loaded on the carbon nanofibers. In the present study, 30 wt % metal oxides (15 wt % MnO<sub>x</sub> and 15 wt % CeO<sub>2</sub>) were successfully deposited on the carbon nanofibers, and the sorbent yielded the highest Hg<sup>0</sup> removal efficiency (>90%) within 120⁻220 °C under a N<sub>2</sub>/O<sub>2</sub> atmosphere. An increase in the amount of highly dispersed metal oxides provided abundant active species for efficient Hg<sup>0</sup> removal, such as active oxygen species and Mn<sup>4+</sup> cations. Meanwhile, the carbon nanofiber framework provides the pathway for charge transfer during the heterogeneous Hg<sup>0</sup> capture reaction processes. Under a N<sub>2</sub>+6%O<sub>2</sub> atmosphere, a majority of Hg<sup>0</sup> was removed via chemisorption reactions. The effects of flue gas composition were also investigated. O<sub>2</sub> replenished the active oxygen species on the surface and thus greatly promoted the Hg<sup>0</sup> removal efficiency. SO<sub>2</sub> had an inhibitory effect on Hg<sup>0</sup> removal, but NO facilitated Hg<sup>0</sup> capture performance. Overall, carbon nanofibers seems to be a good candidate for the support and MnO<sub>x</sub>⁻CeO<sub>2</sub>/CNFs(OX) may be promising for Hg<sup>0</sup> removal from coal-fired flue gas.
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