Study on the adsorption and oxidation mechanism of mercury by HCl over γ-Fe<sub>2</sub>O<sub>3</sub> catalyst

ZHOU Wen-bo; NIU Sheng-li; WANG Jun; LI Ying; HAN Kui-hua; WANG Yong-zheng; LU Chun-mei; ZHU Ying

doi:10.1016/S1872-5813(21)60098-1

Volume 49 Issue 11

Nov. 2021

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Article Navigation > Journal of Fuel Chemistry and Technology > 2021 > 49(11): 1716-1723

ZHOU Wen-bo, NIU Sheng-li, WANG Jun, LI Ying, HAN Kui-hua, WANG Yong-zheng, LU Chun-mei, ZHU Ying. Study on the adsorption and oxidation mechanism of mercury by HCl over γ-Fe2O3 catalyst[J]. Journal of Fuel Chemistry and Technology, 2021, 49(11): 1716-1723. doi: 10.1016/S1872-5813(21)60098-1

Citation:

ZHOU Wen-bo, NIU Sheng-li, WANG Jun, LI Ying, HAN Kui-hua, WANG Yong-zheng, LU Chun-mei, ZHU Ying. Study on the adsorption and oxidation mechanism of mercury by HCl over γ-Fe₂O₃ catalyst[J]. Journal of Fuel Chemistry and Technology, 2021, 49(11): 1716-1723. doi: 10.1016/S1872-5813(21)60098-1

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Study on the adsorption and oxidation mechanism of mercury by HCl over γ-Fe₂O₃ catalyst

doi: 10.1016/S1872-5813(21)60098-1

1.
School of Energy and Power Engineering, Shandong University, Jinan 250061, China
2.
Advanced Materials Institute, Qilu University of Technology (Shandong Academy of Science), Jinan 250014, China

Funds: The project was supported by the Important Project in the Scientific Innovation of Shandong Province (2019JZZY020305).

Received Date: 2021-03-26
Rev Recd Date: 2021-04-28

Available Online: 2021-05-18

Publish Date: 2021-11-30

Abstract

Abstract

The mechanism of adsorption and oxidation of Hg⁰ by HCl on γ-Fe₂O₃ surface was investigated by density functional theory (DFT) calculation. The adsorption models of Hg⁰, HCl, HgCl and HgCl₂ on γ-Fe₂O₃(001) surface were constructed, and the reaction mechanism of catalytic oxidation of Hg⁰by HCl on γ-Fe₂O₃ surface was analyzed. The results illustrate that the Hg⁰ tends to be chemically adsorbed at Fe_oct site. HCl can be dissociated and adsorbed on the surface of the catalyst to form adsorbed Cl and hydroxyl groups, and promote the adsorption of Hg⁰. HgCl can be molecularly chemisorbed upon γ-Fe₂O₃(001) and act as an intermediate. HgCl₂ tends to be adsorbed in parallel on the surface of γ-Fe₂O₃. HCl oxidizes Hg⁰ on γ-Fe₂O₃(001) following the L-H mechanism: chemically adsorbed Hg⁰ reacts with dissociatively adsorbed HCl. By measuring the energy distribution of the reaction path, the oxidation process of Hg⁰ on the surface of γ-Fe₂O₃ was studied. The heterogeneous oxidation of Hg⁰ by HCl proceeds on a two-step reaction pathway: Hg⁰(ads)→HgCl(ads)→HgCl₂(ads).
- Hg⁰,
- γ-Fe₂O₃,
- HCl,
- catalytic oxidation mechanism,
- DFT

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References(35)

References

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