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Conocimientos sobre el mecanismo de la hidroformilación en tándem de alqueno sobre un catalizador nanoestructurado
Ji Su1, Chenlu Xie2, Chen Chen2
1Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|September 3, 2016
Resumen
La catálisis en tándem utilizando una nueva nanoestructura CeO2-Pt@mSiO2 mejora la selectividad para la producción de propano. Este estudio aclara el mecanismo, allanando el camino para el diseño de catalizadores heterogéneos avanzados.
Área de la Ciencia:
- Catálisis heterogénea
- Ciencias de los nanomateriales
- Ingeniería de la reacción química
Sus antecedentes:
- La catálisis en tándem permite reacciones secuenciales selectivas dentro de una sola nanoestructura.
- Los estudios previos sobre la producción de propano a través del metanol y el etileno carecían de comprensión mecánica debido a los catalizadores no definidos.
- El logro de una alta selectividad en la hidroformilación en tándem sigue siendo un desafío.
Objetivo del estudio:
- Diseñar y sintetizar un catalizador 3D estable y bien definido (CeO2-Pt@mSiO2) para el estudio de la hidroformilación en tándem.
- Investigar el mecanismo y los factores que influyen en la selectividad del producto en la conversión del etileno en propanal.
- Explorar la aplicación de este catalizador en la hidroformilación en tándem de otros alquenos como el propileno y el 1-buteno.
Principales métodos:
- Síntesis de un catalizador tridimensional CeO2-Pt@mSiO2 con interfaces definidas.
- Investigación de la conversión de etileno en propanal por medio de la hidroformilación en tándem bajo diversas condiciones.
- Estudios comparativos con diferentes alquenos (propileno, 1-buteno) y experimentos de control.
- Análisis mecanicista detallado para comprender la mejora de la selectividad.
Principales resultados:
- El catalizador CeO2-Pt@mSiO2 logró una selectividad de hasta el 80% para la producción de propano a partir de etileno.
- Se encontró que la presencia de etileno moderaba la descomposición del metanol, suprimiendo la acumulación de hidrógeno y favoreciendo la formación de propano.
- Los intermediarios de reacción migraron eficientemente entre las interfaces catalíticas, promoviendo la hidroformilación directa.
- Se observó una producción similar de aldehído para el propileno y el 1-buteno.
Conclusiones:
- El estudio aclara los principios mecanicistas detrás de una mayor selectividad en la hidroformilación en tándem utilizando CeO2-Pt@mSiO2.
- Los efectos sinérgicos y las vías de reacción alteradas son ventajas clave de este enfoque de catálisis en tándem.
- Este trabajo proporciona una base para el diseño racional de nuevos catalizadores heterogéneos para transformaciones químicas selectivas.
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