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.
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页码：1716 / 1723
页数：7
相关论文
共 35 条
  • [1] LIU J, QU W, ZHENG C G., Theoretical studies of mercury-bromine species adsorption mechanism on carbonaceous surface[J], Proc Combust Inst, 34, 2, pp. 2811-2819, (2013)
  • [2] YANG Ying-ju, ZHANG Ai-jia, LIU Jing, WANG Zhen, YU Ying-ni, Effect of NO on the performance of Cu-Mn spinel sorbent in the removal of Hg<sup>0</sup> from flue gas, J Fuel Chem Technol, 48, 12, pp. 1461-1465, (2020)
  • [3] KRABBENHOFT D P, SUNDERLAND E M., Global change and mercury[J], Science, 341, 6153, pp. 1457-1458, (2013)
  • [4] XIN Feng, WEI Shu-zhou, ZHANG Jun-feng, MA Si-ming, ZHAO Yong-chun, ZHANG Jun-ying, Research progress on the removal of mercury from coal-fired flue gas by using non-carbon-based adsorbents, J Fuel Chem Technol, 48, 12, pp. 1409-1420, (2020)
  • [5] SELIN N E., A proposed global metric to aid mercury pollution policy[J], Science, 360, 6389, pp. 607-609, (2018)
  • [6] ZHOU Z J, LIU X W, LIAO Z Q, SHAO H Z, LV C, HU Y C, XU M H., Manganese doped CeO<sub>2</sub>-ZrO<sub>2</sub> catalyst for elemental mercury oxidation at low temperature, Fuel Process Technol, 152, pp. 285-293, (2016)
  • [7] STOLLE R, KOESER H, GUTBERLET H., Oxidation and reduction of mercury by SCR DeNO<sub>x</sub> catalysts under flue gas conditions in coal fired power plants, Appl Catal B: Environ, 144, pp. 486-497, (2014)
  • [8] GHAREBAGHI M, HUGHES K J, PORTER R T J, POURKASHANIAN M, WILLIAMS A., Mercury speciation in air-coal and oxy-coal combustion: a modelling approach, Proc Combust Inst, 33, 2, pp. 1779-1786, (2011)
  • [9] ZHOU Z J, LIU X W, ZHAO B, CHEN Z G, SHAO H Z, WANG L L, XU M H., Effects of existing energy saving and air pollution control devices on mercury removal in coal-fired power plants[J], Fuel Process Technol, 131, pp. 99-108, (2015)
  • [10] GAO Y, LI Z., A DFT study of the Hg<sup>0</sup> oxidation mechanism on the V<sub>2</sub>O<sub>5</sub>-TiO<sub>2</sub> (001) surface, Mol Catal, 433, pp. 372-382, (2017)
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