Density Functional Theory Study on Mechanism of Mercury Removal by CeO2 Modified Activated Carbon
Abstract
:1. Introduction
2. Models and Computational Details
2.1. AC and CeO2-AC Models
2.2. Computational Parameters
3. Results and Discussion
3.1. Hg0 Adsorption Mechanism
3.2. HCl Adsorption Mechanism
3.3. HgCl Adsorption Mechanism
3.4. HgCl2 Adsorption Mechanism
3.5. Hg0 Oxidation Mechanism
4. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Bond Type | C–C | C–H | C–O | C≡C | Ce–O | |
---|---|---|---|---|---|---|
Bond Length (Å) | Conventional AC model | 1.369–1.439 | 1.092 | - | 1.267 | - |
CeO2 modified AC model | 1.394–1.460 | 1.093 | 1.348 | 1.275 | 2.217 |
CeO2-AC Model | AC Model | ||||
---|---|---|---|---|---|
Configurations | RHg–Ce (Å) | Eads (kJ/mol) | Configurations | RHg–C (Å) | Eads (kJ/mol) |
1A | 3.431 | −46.94 | 1A* | 2.511 | −119.92 |
1B | 3.508 | −42.05 | 1B* | 2.462/2.464 | −146.01 |
CeO2-AC Surface | AC Surface | ||||||
---|---|---|---|---|---|---|---|
Configurations | RX–Ce(Å) * | RH–Cl(Å) | Eads(kJ/mol) | Configurations | RX–C(Å) * | RH–Cl(Å) | Eads(kJ/mol) |
2A | 2.633/2.157 | 4.036 | −174.27 | 2A* | 1.095 | 2.707 | −149.38 |
2B | 2.623 | 5.291 | −371.63 | 2B* | 2.373 | 1.089 | −254.78 |
2C | 3.088 | 1.361 | −54.85 | 2C* | 2.257 | 1.088 | −255.40 |
2D | 3.071 | 1.362 | −54.97 | 2D* | 3.496/3.501 | 1.291 | −41.20 |
2E | 3.226 | 1.343 | −52.63 | 2E* | 2.411/2.385 | 1.304 | −55.79 |
CeO2-AC Surface | AC Surface | ||||||
---|---|---|---|---|---|---|---|
Configurations | RX–Ce (Å) * | RHg–Cl (Å) | Eads (kJ/mol) | Configurations | RHg–C (Å) * | RHg–Cl (Å) | Eads (kJ/mol) |
3A | 2.623 | 7.191 | −281.58 | 3A* | 2.149 | 2.391 | −258.70 |
3B | 2.625 | 5.219 | −294.50 | 3B* | 2.156 | 2.393 | −259.47 |
3C | 3.177 | 2.556 | −153.09 | 3C* | 2.323/2.427 | 3.689 | −301.32 |
3D | 3.275 | 2.580 | −139.80 | - | - | - | - |
CeO2-AC Surface | AC Surface | |||||||
---|---|---|---|---|---|---|---|---|
Configurations | RX–Ce (Å) | RHg–Cl (Å) | Eads (kJ/mol) | Configurations | RHg–C (Å) | RHg–Cl (Å) | ∠Cl–Hg–Cl (°) | Eads (kJ/mol) |
4A | 2.599 | 5.323/2.672 | −202.70 | 4A* | 2.121 | 2.368/3.468 | - | −369.19 |
4B | 2.616 | 5.063/2.586 | −287.46 | 4B* | 6.043/6.119 | 2.356/2.362 | 179.82 | −101.54 |
4C | 2.640/2.643 | 3.886/3.857 | −399.03 | 4C* | 3.202/3.258 | 2.367/2.368 | 171.63 | −110.80 |
- | - | - | - | 4D* | 2.271/2.309 | 2.546/2.515 | 92.65 | −186.98 |
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Zhao, L.; Wu, Y.-w.; Han, J.; Wang, H.-x.; Liu, D.-j.; Lu, Q.; Yang, Y.-p. Density Functional Theory Study on Mechanism of Mercury Removal by CeO2 Modified Activated Carbon. Energies 2018, 11, 2872. https://doi.org/10.3390/en11112872
Zhao L, Wu Y-w, Han J, Wang H-x, Liu D-j, Lu Q, Yang Y-p. Density Functional Theory Study on Mechanism of Mercury Removal by CeO2 Modified Activated Carbon. Energies. 2018; 11(11):2872. https://doi.org/10.3390/en11112872
Chicago/Turabian StyleZhao, Li, Yang-wen Wu, Jian Han, Han-xiao Wang, Ding-jia Liu, Qiang Lu, and Yong-ping Yang. 2018. "Density Functional Theory Study on Mechanism of Mercury Removal by CeO2 Modified Activated Carbon" Energies 11, no. 11: 2872. https://doi.org/10.3390/en11112872