### Abstract

Understanding the oxidation pathways of mercury in the flue gases of coal combustion is instrumental to its capture due to the water-soluble nature of oxidized mercury. The model developed in this work is based on theoretical rate constant calculations for the following mercury oxidation reactions involving chlorine species: Hg + Cl + M → HgCl + M (1) Hg + HCl → HgCl + H (2) Hg + Cl2 → HgCl + Cl (3) Hg + Cl2 + M → HgCl2 + M (4) HgCl + HCl → HgCl2 + H (5) HgCl + Cl2 → HgCl2 + Cl (6) HgCl + Cl +M → HgCl2 + M (7) Transition state theory was used to calculate bimolecular rates and RRKM theory was used for the rate calculations involving the unimolecular reactions. Due to mercury having 80 electrons, the most recently developed effective core potentials which include relativistic effects have been used for mercury. Ab initio calculations were carried out using Gaussian98 software at both the QCISD and B3LYP levels of theory using relativistic Stuttgart and SBJK pseudopotentials. The choice of method and basis set combination was validated through a detailed comparison of theoretical geometry and heats of reaction predictions to experimental data available in the literature. A Chemkin derived model was developed based upon the theoretical predictions. The model predicts that mercury cannot be oxidized homogeneously unless chlorine levels are greater than 700 ppm.

Original language | English (US) |
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Title of host publication | AIChE Annual Meeting, Conference Proceedings |

Pages | 11535 |

Number of pages | 1 |

State | Published - 2005 |

Externally published | Yes |

Event | 05AIChE: 2005 AIChE Annual Meeting and Fall Showcase - Cincinnati, OH, United States Duration: Oct 30 2005 → Nov 4 2005 |

### Other

Other | 05AIChE: 2005 AIChE Annual Meeting and Fall Showcase |
---|---|

Country | United States |

City | Cincinnati, OH |

Period | 10/30/05 → 11/4/05 |

### Fingerprint

### ASJC Scopus subject areas

- Engineering(all)

### Cite this

*AIChE Annual Meeting, Conference Proceedings*(pp. 11535)

**An Ab initio investigation of mercury oxidation in combustion flue gases.** / Wilcox, Jennifer; Blowers, Paul; Wendt, Jost O L.

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

*AIChE Annual Meeting, Conference Proceedings.*pp. 11535, 05AIChE: 2005 AIChE Annual Meeting and Fall Showcase, Cincinnati, OH, United States, 10/30/05.

}

TY - GEN

T1 - An Ab initio investigation of mercury oxidation in combustion flue gases

AU - Wilcox, Jennifer

AU - Blowers, Paul

AU - Wendt, Jost O L

PY - 2005

Y1 - 2005

N2 - Understanding the oxidation pathways of mercury in the flue gases of coal combustion is instrumental to its capture due to the water-soluble nature of oxidized mercury. The model developed in this work is based on theoretical rate constant calculations for the following mercury oxidation reactions involving chlorine species: Hg + Cl + M → HgCl + M (1) Hg + HCl → HgCl + H (2) Hg + Cl2 → HgCl + Cl (3) Hg + Cl2 + M → HgCl2 + M (4) HgCl + HCl → HgCl2 + H (5) HgCl + Cl2 → HgCl2 + Cl (6) HgCl + Cl +M → HgCl2 + M (7) Transition state theory was used to calculate bimolecular rates and RRKM theory was used for the rate calculations involving the unimolecular reactions. Due to mercury having 80 electrons, the most recently developed effective core potentials which include relativistic effects have been used for mercury. Ab initio calculations were carried out using Gaussian98 software at both the QCISD and B3LYP levels of theory using relativistic Stuttgart and SBJK pseudopotentials. The choice of method and basis set combination was validated through a detailed comparison of theoretical geometry and heats of reaction predictions to experimental data available in the literature. A Chemkin derived model was developed based upon the theoretical predictions. The model predicts that mercury cannot be oxidized homogeneously unless chlorine levels are greater than 700 ppm.

AB - Understanding the oxidation pathways of mercury in the flue gases of coal combustion is instrumental to its capture due to the water-soluble nature of oxidized mercury. The model developed in this work is based on theoretical rate constant calculations for the following mercury oxidation reactions involving chlorine species: Hg + Cl + M → HgCl + M (1) Hg + HCl → HgCl + H (2) Hg + Cl2 → HgCl + Cl (3) Hg + Cl2 + M → HgCl2 + M (4) HgCl + HCl → HgCl2 + H (5) HgCl + Cl2 → HgCl2 + Cl (6) HgCl + Cl +M → HgCl2 + M (7) Transition state theory was used to calculate bimolecular rates and RRKM theory was used for the rate calculations involving the unimolecular reactions. Due to mercury having 80 electrons, the most recently developed effective core potentials which include relativistic effects have been used for mercury. Ab initio calculations were carried out using Gaussian98 software at both the QCISD and B3LYP levels of theory using relativistic Stuttgart and SBJK pseudopotentials. The choice of method and basis set combination was validated through a detailed comparison of theoretical geometry and heats of reaction predictions to experimental data available in the literature. A Chemkin derived model was developed based upon the theoretical predictions. The model predicts that mercury cannot be oxidized homogeneously unless chlorine levels are greater than 700 ppm.

UR - http://www.scopus.com/inward/record.url?scp=33645641426&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33645641426&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:33645641426

SP - 11535

BT - AIChE Annual Meeting, Conference Proceedings

ER -