JZUS - Journal of Zhejiang University SCIENCE

Journal of Zhejiang University SCIENCE A 2024 Vol.25 No.8 P.680-686

Enhancement in the Hg⁰ oxidation efficiency and sulfur resistance of CuCl₂-modified MnO_x-CeO_x nanorod catalysts

Author(s): Shujie GAO, Yongjin HU, Zhichang JIANG, Xiaoxiang WANG, Dong YE, Changxing HU
Affiliation(s): College of Quality & Safety Engineering, China Jiliang University, Hangzhou 310018, China; more
Corresponding email(s): Richard32@126.com, huchx@zju.edu.cn
Key Words: Hg⁰ oxidation, CuCl₂ modification, MnO_x-CeO_x nanorods, Sulfur resistance, Oxidation activity

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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

作者：高淑洁¹，胡永金¹，蒋志昌¹，王晓祥²，叶栋¹，胡长兴³
机构：¹中国计量大学，质量与安全工程学院，中国杭州，310018；²浙江大学，化工学院，工业生态与环境研究所，中国杭州，310027；³浙大宁波理工学院，机电与能源工程学院，中国宁波，315100
目的：针对燃煤电站多变的烟气条件，研究适用于高汞、含硫烟气的催化剂。
创新点：1.通过水热法合成锰铈氧化物纳米棒，可实现高汞含硫烟气条件下的高效脱汞；2.通过添加CuCl₂，在保证催化剂的汞氧化性能的同时，提升其抗硫性能。
方法：利用固定床微反应器对催化剂的汞氧化性能进行研究，并结合物化表征建立催化剂的构效关系，进而揭示CuCl₂改性催化剂的抗硫机理。
结论：1.添加CuCl₂提升了催化剂的汞氧化性能：在150~250°C温度区间内，催化剂的汞养护效率为100%；在含硫气氛下反应320 min后，锰铈氧化物的汞氧化效率由100%下降到78%；对于CuCl₂改性催化剂，共氧化性能依旧维持在100%。2.对于锰铈氧化物催化剂，Mn⁴⁺为主要的活性位点；对于CuCl₂改性催化剂，除了Mn⁴⁺外，Cl^?也是其中的活性位点。3.在含硫气氛下，Mn⁴⁺利用量的下降是导致锰铈氧化物催化剂活性下降的主要原因，而高反应活性Cl^?的存在是CuCl₂改性催化剂保持高汞脱除效率的主要原因。

关键词：汞氧化；CuCl₂改性；锰铈氧化物纳米棒；抗硫性能；氧化活性

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