Nano-molecular response of bituminous coal to ScCO₂ at different stage: Experiments and ReaxFF-MD/DFT insights
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| Titel: | Nano-molecular response of bituminous coal to ScCO₂ at different stage: Experiments and ReaxFF-MD/DFT insights |
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| Autoren: | Kui Dong, Jianhua Xiang, Shaoqi Kong, Bingyi Jia, Zhiyu Niu |
| Quelle: | Fuel Processing Technology, Vol 277, Iss , Pp 108305- (2025) |
| Verlagsinformationen: | Elsevier, 2025. |
| Publikationsjahr: | 2025 |
| Bestand: | LCC:Fuel LCC:Renewable energy sources |
| Schlagwörter: | ScCO2, Bituminous coal, Nano-molecular scale, Reaction stage, Fuel, TP315-360, Renewable energy sources, TJ807-830 |
| Beschreibung: | The interaction between supercritical CO₂ (ScCO₂) and coal alters the physicochemical properties of the coal in a staged manner. This study quantitatively investigates the nano-molecular structural response of bituminous to ScCO₂ exposure using a combination of experiments and ReaxFF-MD/DFT simulations. The results show that:In the swelling stage, the coal matrix expanded and early radical formation occurred, leading to a reduction in intramolecular pore volume from 0.0326 to 0.0318 cm3/g, while intermolecular pores increased from 0.0119 to 0.0145 cm3/g, Car-Car from 145 to 149, Cal-H from 103 to 92, weak van der Waals and hydrogen bonds were cleaved. In the dissolution stage, aliphatic chains degraded and oxygen-containing groups formed, intramolecular and intermolecular pores expanded to 0.0334 and 0.0165 cm3/g, respectively, increasing Car–Car bonds to 150, and Cal-H to 89, electron density recovered with the development of aromatic conjugation and polar groups In the rearrangement stage, radicals recombined into new aromatics, compressing intermolecular pores to 0.0160 cm3/g, while intramolecular pores increased to 0.0346 cm3/g, reducing Car–Car bonds to 142 and Cal-H to 84, electrostatic potential strengthened, indicating molecular stabilization.This work provides a novel, stage-specific, and quantitatively supported mechanism of bituminous evolution under ScCO₂ conditions, offering theoretical insight into molecular-scale optimization strategies for CO₂-ECBM. |
| Publikationsart: | article |
| Dateibeschreibung: | electronic resource |
| Sprache: | English |
| ISSN: | 0378-3820 |
| Relation: | http://www.sciencedirect.com/science/article/pii/S0378382025001298; https://doaj.org/toc/0378-3820 |
| DOI: | 10.1016/j.fuproc.2025.108305 |
| Zugangs-URL: | https://doaj.org/article/33e13a0d88e4483a91e4c560e126443a |
| Dokumentencode: | edsdoj.33e13a0d88e4483a91e4c560e126443a |
| Datenbank: | Directory of Open Access Journals |
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Nájsť tento článok vo Web of Science | Abstract: | The interaction between supercritical CO₂ (ScCO₂) and coal alters the physicochemical properties of the coal in a staged manner. This study quantitatively investigates the nano-molecular structural response of bituminous to ScCO₂ exposure using a combination of experiments and ReaxFF-MD/DFT simulations. The results show that:In the swelling stage, the coal matrix expanded and early radical formation occurred, leading to a reduction in intramolecular pore volume from 0.0326 to 0.0318 cm3/g, while intermolecular pores increased from 0.0119 to 0.0145 cm3/g, Car-Car from 145 to 149, Cal-H from 103 to 92, weak van der Waals and hydrogen bonds were cleaved. In the dissolution stage, aliphatic chains degraded and oxygen-containing groups formed, intramolecular and intermolecular pores expanded to 0.0334 and 0.0165 cm3/g, respectively, increasing Car–Car bonds to 150, and Cal-H to 89, electron density recovered with the development of aromatic conjugation and polar groups In the rearrangement stage, radicals recombined into new aromatics, compressing intermolecular pores to 0.0160 cm3/g, while intramolecular pores increased to 0.0346 cm3/g, reducing Car–Car bonds to 142 and Cal-H to 84, electrostatic potential strengthened, indicating molecular stabilization.This work provides a novel, stage-specific, and quantitatively supported mechanism of bituminous evolution under ScCO₂ conditions, offering theoretical insight into molecular-scale optimization strategies for CO₂-ECBM. |
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| ISSN: | 03783820 |
| DOI: | 10.1016/j.fuproc.2025.108305 |