| Summary: | Herein, a series of Co-Fe mixed oxide modified ZSM-5 adsorbents were synthesized using the ultrasonic-assisted impregnation method for the capture of elemental mercury. In comparison with other samples, Co<sub>4</sub>Fe<sub>1</sub>-ZSM-5 produced a relatively better performance, with the removal efficiency of around 96.6% Hg<sup>0</sup> and the adsorption capacity of around 901.63 ug/mg Hg<sup>0</sup> achieved at 120 °C. The interaction between CoO<i><sub>x</sub></i> and FeO<i><sub>x</sub></i> improved the reducibility of oxygen species, thus promoting the oxidation of Hg<sup>0</sup>. Among a variety of other gas components, O<sub>2</sub> and NO exerted a positive effect on Hg<sup>0</sup>, which improved its removal to a certain extent. By contrast, SO<sub>2</sub> caused an adverse effect on the capture of Hg<sup>0</sup>, which could be reversed to some degree by the introduction of 5% O<sub>2</sub>. After five cycles, the mercury removal efficiency of Co<sub>4</sub>Fe<sub>1</sub>-ZSM-5 remained above 90%, suggesting excellent recyclability. Finally, XPS analysis was conducted to reveal that Mars–Maessen mechanisms are dominant in the process of mercury adsorption.
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