Abstract: Mercury emission has become a great environmental concern because of its high toxicity, bioaccumulation, and persistence. Adsorption is an effective method to remove Hg⁰ from coal-fired flue gas, with adsorbents playing a dominant role. Extensive investigations have been conducted on the use of CuO-based materials for Hg⁰ removal, and some fruitful results have been obtained. In this review, we summarize advances in the application of CuO-based materials for Hg⁰ capture. Firstly, the fundamentals of CuO, including its crystal information and synthesis methods, are introduced. Then, the Hg⁰ removal capability of some typical CuO-based adsorbents is discussed. Considering that coal-fired flue gas also contains a certain amount of NO, SO₂, H₂O, NH₃, and HCl, the impacts of these species on adsorbent Hg⁰ removal efficiency are summarized next. By generalizing the mechanisms dominating the Hg⁰ removal process, the rate-determining step and the key intermediates can be discovered. Apart from Hg⁰, some other air pollutants, such as CO, NO_x, and volatile organic compounds (VOCs), account for a certain portion of flue gas. In view of their similar abatement mechanisms, simultaneous removal of Hg⁰ and other air pollutants has become a hot topic in the environmental field. Considering the Hg⁰ re-emission phenomena in wet flue gas desulfurization (WFGD), mercury capture performance under different conditions in this device is discussed. Finally, we conclude that new adsorbents suitable for long-term operation in coal-fired flue gas should be developed to realize the effective reduction of mercury emissions.

氧化铜基脱汞剂的进展研究

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