Hydrothermal synthesis of Mo-V mixed oxides possessing several crystalline phases and their performance in the catalytic oxydehydration of glycerol to acrylic acid
The one-step oxydehydration of glycerol to acrylic acid over molybdenum and vanadium mixed oxides was investigated. The Mo-V oxide catalysts were prepared by a simple hydrothermal method under different synthesis and calcination atmospheres and were characterized by in situ XRD, TPD-NH3, N2 adsorpti...
| Autores: | , , , , , |
|---|---|
| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2017 |
| País: | Brasil |
| Institución: | Universidade Estadual Paulista (UNESP) |
| Repositorio: | Repositório Institucional da UNESP |
| Idioma: | inglés |
| OAI Identifier: | oai:repositorio.unesp.br:11449/178799 |
| Acceso en línea: | http://dx.doi.org/10.1016/j.cattod.2017.04.006 http://hdl.handle.net/11449/178799 |
| Access Level: | acceso abierto |
| Palabra clave: | Acrylic acid Bifunctional catalysts Glycerol oxydehydration Hydrothermal synthesis Molybdenum-vanadium mixed oxides |
| Sumario: | The one-step oxydehydration of glycerol to acrylic acid over molybdenum and vanadium mixed oxides was investigated. The Mo-V oxide catalysts were prepared by a simple hydrothermal method under different synthesis and calcination atmospheres and were characterized by in situ XRD, TPD-NH3, N2 adsorption/desorption, X-ray absorption near vanadium K-edge spectroscopy and thermogravimetry. The catalytic performance of the samples at different temperatures (290, 320 and 350 °C) and under different gas flow compositions (20% O2 in N2, 100% O2, or 100% N2) revealed that the arrangement of the crystallographic structures of the active phases directly influenced the catalytic performance. It was found that the catalysts heat-treated in oxidizing atmosphere gave superior catalytic results comparing with the catalysts heat-treated in inert atmosphere due to the equilibrium between the crystalline phases MoVO5 and Mo4.65V0.35O14 that contains V+4 and V+5. Catalytic oxydehydration at 320 °C under a flow of 100% O2 gave the best performance, achieving selectivity of 33.5% towards acrylic acid and 100% conversion of glycerol. |
|---|