Interaction mechanism between heavy metals and Ce-doped CaO in flue gas of coal combustion

ZHOU Xin-yue; WU Yang-wen; MI Teng-ge; LIU Ji; XU Ming-xin; ZHAO Li; LU Qiang

Volume 48 Issue 12

Dec. 2020

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Article Navigation > Journal of Fuel Chemistry and Technology > 2020 > 48(12): 1520-1529

ZHOU Xin-yue, WU Yang-wen, MI Teng-ge, LIU Ji, XU Ming-xin, ZHAO Li, LU Qiang. Interaction mechanism between heavy metals and Ce-doped CaO in flue gas of coal combustion[J]. Journal of Fuel Chemistry and Technology, 2020, 48(12): 1520-1529.

Citation:

ZHOU Xin-yue, WU Yang-wen, MI Teng-ge, LIU Ji, XU Ming-xin, ZHAO Li, LU Qiang. Interaction mechanism between heavy metals and Ce-doped CaO in flue gas of coal combustion[J]. Journal of Fuel Chemistry and Technology, 2020, 48(12): 1520-1529.

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Interaction mechanism between heavy metals and Ce-doped CaO in flue gas of coal combustion

National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, Beijing 102206, China

Funds:

the National Natural Science Foundation of China 51922040

the National Natural Science Foundation of China 51876060

Grants from Fok Ying Tung Education Foundation 161051

Fundamental Research Funds for the Central Universities 2020DF01

More Information

Corresponding author: LU Qiang, E-mail:qianglu@mail.ustc.edu.cn, qlu@ncepu.edu.cn
Received Date: 2020-09-09
Rev Recd Date: 2020-10-01

Available Online: 2021-01-23

Publish Date: 2020-12-10

Abstract

Abstract

Calcium oxide (CaO) has been widely used as an adsorbent in the purification of heavy metals in coal-fired flue gas. However, the adsorption efficiency is limited and a further modification is needed. The cerium (Ce) modification can redistribute the surface electrons and enhance the chemical activity of CaO. Therefore, the Ce-CaO (100) periodic model was established to study the adsorption mechanism of mercury, selenium, and lead pollutants in the coal-fired flue gas. The results show that, except for the physical adsorption of Hg⁰ on the Ce-CaO (100) surface, the other heavy metal pollutants are chemically adsorbed on the surface. The Ce-site and O-site are the main active adsorption sites of heavy metal pollutants. Intense charge transfer and strong interaction are observed between adsorption molecules and Ce-CaO (100). Moreover, the adsorption capacity of Ce-doped CaO (100) surface for heavy metal pollutants has been improved, especially the significantly increased capture capacity on Se⁰, SeO₂ and HgCl₂.
- coal-fired flue gas,
- heavy metals,
- modified CaO,
- adsorption mechanism,
- density functional theory

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References(49)

References

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