Synergistic effect in the CO2-oxidative dehydrogenation of propane to propylene over IrPt catalysts supported on mesoporous Mg-SBA-15
The effect of partial Pt substitution by Ir on the propylene formation via CO2-oxidative dehydrogenation of propane (CO2-ODH) has been investigated. To decrease coke formation, the synthetized Pt, Ir and PtIr catalysts were supported on mesoporous silica (SBA-15) modified with Mg (∼2.9 wt%). The bes...
| Autores: | , , , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2025 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/425166 |
| Acceso en línea: | http://hdl.handle.net/10261/425166 https://www.scopus.com/inward/record.uri?eid=2-s2.0-105009010983&doi=10.1016%2Fj.micromeso.2025.113730&partnerID=40&md5=bcc2523d8c30a76ea83fc37133bbefb6 |
| Access Level: | acceso abierto |
| Palabra clave: | Carbon dioxide Magnesium oxide-SBA-15 Mild oxidative dehydrogenation Platinum-iridium catalysts Propane to propylene |
| Sumario: | The effect of partial Pt substitution by Ir on the propylene formation via CO2-oxidative dehydrogenation of propane (CO2-ODH) has been investigated. To decrease coke formation, the synthetized Pt, Ir and PtIr catalysts were supported on mesoporous silica (SBA-15) modified with Mg (∼2.9 wt%). The best propylene production was archived with the PtIrMg-1.5 catalyst showing a highest degree of Pt substitution with Ir (Pt/Ir at a ratio of 1.5). Characterization of the catalyst by various techniques (ICP-OES, XRD, FTIR of adsorbed pyridine, XPS and HRTEM) showed that partial substitution of Pt by Ir influences the nature of the surface acid sites and leads to easier reduction of Pt2+ species. The catalyst efficiency toward propane formation from CO2 follows the trend: PtIrMg-1.5 > PtIrMg-4 > PtMg > IrMg. The highest propylene selectivity exhibited IrMg catalyst showing the lowest propane conversion. It was found that propane conversion decreases lineally with increasing Brønsted acidity and increases with increasing Lewis-to-Brønsted acidity ratio. The synergy effect observed in reaction over PtIrMg-1.5 catalyst was attributed to the cumulative effects of its lowest Brønsted acidity, largest Ir content, Pt-Ir alloy formation and the stabilizing effect of the MgO nanoparticles decorating support surface. © 2025 The Authors |
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