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

被引：0

作者：

Zhou W.-B. ^{[1
]}

Niu S.-L. ^{[1
]}

Wang J. ^{[1
]}

Li Y. ^{[1
]}

Han K.-H. ^{[1
]}

Wang Y.-Z. ^{[1
]}

Lu C.-M. ^{[1
]}

Zhu Y. ^{[2
]}

机构：

[1] School of Energy and Power Engineering, Shandong University, Jinan

[2] Advanced Materials Institute, Qilu University of Technology (Shandong Academy of Science), Jinan

来源：

Ranliao Huaxue Xuebao/Journal of Fuel Chemistry and Technology | 2021年 / 49卷 / 11期

关键词：

Catalytic oxidation mechanism; DFT; HCl; Hg[!sup]0[!/sup; Γ-Fe[!sub]2[!/sub]O[!sub]3[!/sub;

D O I：

10.1016/S1872-5813(21)60098-1

中图分类号：

学科分类号：

摘要：

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 Feoct 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). © 2021, Science Press. All right reserved.

引用

页码：1716 / 1723

页数：7

共 35 条

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