Abstract: In this study, a series of CuCl₂-modified MnO_x-CeO_x nanorods were synthesized for the oxidation of Hg⁰. The addition of CuCl₂ resulted in an enhancement in the catalyst's Hg⁰ oxidation ability, and Hg⁰ oxidation efficiency reached >97% from 150 to 250 °‍C. In the MnO_x-CeO_x catalysts, Mn⁴⁺ played the role of the active species for Hg⁰ oxidization, but in the CuCl₂-doped catalysts Cl^- also contributed to Hg⁰ oxidation, conferring the superior performance of these samples. The introduction of SO₂ led to a decrease in the availability of Mn⁴⁺, and the Hg⁰ oxidation efficiency of MnO_x-CeO_x decreased from about 100% to about 78%. By contrast, CuCl₂-promoted samples maintained a Hg⁰ oxidation efficiency of about 100% during the SO₂ deactivation cycle due to the high reactivity of Cl^-.

CuCl₂改性对MnO_x-CeO_x纳米棒催化剂汞氧化性能及抗硫性能的提升机理研究

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