Investigators from Huazhong University of Science and Technology Report New Data on Combustion Science (Comprehensive evolution mechanism of SOx formation during pyrite oxidation)
- February 15, 2019
- 136 views
By a News Reporter-Staff News Editor at Science Letter -- Investigators publish new report on Science - Combustion Science. According to news reporting originating in Hubei, People's Republic of China, by NewsRx journalists, research stated, "Pyrite (FeS2) oxidation during coal combustion is one of the main sources of harmful SO2 emission from coal-fired power plants. Density functional theory (DFT) study was performed to uncover the evolution mechanism of SOx formation during pyrite oxidation."
Financial support for this research came from National Natural Science Foundation of ChinaNational Natural Science Foundation of China (see also Science - Combustion Science).
The news reporters obtained a quote from the research from the Huazhong University of Science and Technology, "The results show that chemisorption mechanism is responsible for O-2, SO2 and SO3 adsorption on FeS2 surface. The presence of formed oxidation layer (Fe2O3) weakens the interaction between O-2 molecule and FeS2 surface. The adsorbed O-2 molecule easily dissociates into active surface O atom for SOx formation. The dissociation reaction of O-2 is activated by 77.38 kJ/mol, and exothermic by 138.46 kJ/mol. Compared to the further oxidation of SO2 into SO3, SO2 prefers to desorb from FeS2 surface. The dominant reaction pathway of SO2 formation from the oxidation of the outermost FeS2 surface layer is a three-step process: surface lattice S oxidation, SO2 desorption and replenishment of S vacancy by activated surface O atom. The elementary reaction of surface lattice S oxidation has an activation energy barrier of 197.96 kJ/mol, and is identified as the rate-limiting step. SO2 formation from the further oxidation of bulk FeS2 layer is controlled by a four-step process: bulk lattice S migration, lattice S oxidation, SO2 desorption and surface O atom deposition. Migration of lattice S from bulk position to the outermost surface shows a high activation energy barrier of 175.83 kJ/mol."
According to the news reporters, the research concluded: "The deposition process of surface O atom is a relatively easy step, and is activated by 21.05 kJ/mol."
For more information on this research see: Comprehensive evolution mechanism of SOx formation during pyrite oxidation. Proceedings of the Combustion Institute, 2019;37(3):2809-2819. Proceedings of the Combustion Institute can be contacted at: Elsevier Science Inc, 360 Park Ave South, New York, NY 10010-1710, USA. (Elsevier - www.elsevier.com; Proceedings of the Combustion Institute - www.journals.elsevier.com/proceedings-of-the-combustion-institute/)
Our news correspondents report that additional information may be obtained by contacting J. Liu, Huazhong University of Science & Technology, Sch Energy & Power Engn, State Key Lab Coal Combust, Wuhan 430074, Hubei, People's Republic of China. Additional authors for this research include Y.J. Yang, F. Liu and Z. Wang.
The direct object identifier (DOI) for that additional information is: https://doi.org/10.1016/j.proci.2018.06.064. This DOI is a link to an online electronic document that is either free or for purchase, and can be your direct source for a journal article and its citation.
(Our reports deliver fact-based news of research and discoveries from around the world.)