Catalytic Oxidation of Elemental Mercury over CuO-WO3/TiO2 in Simulated Coal-fired Flue Gas

doi:10.11930/j.issn.1004-9649.201904117

Abstract

Abstract: Improving the Hg⁰ oxidation activity of the commercial selective catalytic reduction (SCR) catalyst can enhance the mercury removal activity in coal fired flue gas. In this paper, a series of CuO-WO₃/TiO₂ (CuWTi) catalysts were synthesized by step impregnation method for oxidize elemental mercury (Hg⁰) using simulated coal-fired flue gas at 150-350 ℃. The effects of O₂, SO₂ and NO on Hg⁰ oxidation were also investigated and compared with commercial catalyst. The results indicated that the commercial SCR catalyst and the WTi exhibited below 30% rate on Hg⁰ oxidation without HCl in simulated flue gas, while the Cu₂W₈Ti catalyst performed good activity of Hg⁰ oxidation and NO removal. The X-ray photoelectron spectroscopy (XPS) method was used to characterize the catalysts, and the results suggested that the interaction between CuO and WO₃ created abundant chemisorbed oxygen on the catalyst surface, which was beneficial for Hg⁰ oxidation. The Mars-Maessen mechanism was respected in the process of the Hg⁰ oxidation over Cu₂W₈Ti catalyst.

Key words: coal-fired flue gas, Hg emission control, Hg⁰, catalytic oxidation, CuO-WO₃/TiO₂

CLC Number:

X701
TM621.9

CHEN Chuanmin, NIE Guoxin, JIA Wenbo, LIU Songtao, CAO Yue, ZHAO Yi. Catalytic Oxidation of Elemental Mercury over CuO-WO₃/TiO₂ in Simulated Coal-fired Flue Gas[J]. Electric Power, 2019, 52(6): 179-186.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.201904117

https://www.electricpower.com.cn/EN/Y2019/V52/I6/179

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Catalytic Oxidation of Elemental Mercury over CuO-WO₃/TiO₂ in Simulated Coal-fired Flue Gas

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